omfs trst 4.pdf

2006 Oral and Maxillofacial Surgery Self Assessment Tool (OMSSAT)

Administration Dates: April 17 – 28, 2006 The American Board of Oral and Maxillofacial Surgery

2005-2006 Oral and Maxillofacial Surgery Self Assessment Tool (OMSSAT) Committee Patrick J. Louis, DDS, MD, chair Dentoalveolar Surgery David A. Stanton, DMD, DMD, MD, section editor Nabil Abaza Darren Cross Richard D’Innocenzo Sam Farish David Grogan Deepak Kademan Vasiliki Karlis Lawrence Levin Rawle Philbert Anthony Pitrowski Louis Rafetto Kevin Rieck Eric Rippert Rory Sadoff Vernon Sellers Coleman Spector

Medical Assessment and Management of the Surgical Patient Patrick J. Vezeau, DDS, MS, section editor Shawn Bailey Jeffrey Bennett Lionel Candelaria Karen Crowley Kirk Engel Godfrey Funari Andrew Hartwig Robert Hinkle Timothy Holton John Kelly John McCabe Teresa Morgan Noah Sandler Daniel Sarasin Paul Smith William Synan Patrick Vezeau Larry Weeda

Kurt Westlund William Wood

The American Board of Oral and Maxillofacial Surgery

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Cosmetic Surgery David Cottrell, DMD, section section editor Jeffrey Almony Julie Ann Smith James Boyle Michael Will Kamal Busaidy Guillermo Chacon Matthew Dennis Stephaine Drew David Emanuel David Harmatz Holly Hatt Kathleen Herb Pamela Hughes Kurt Hummeldorf Antilano Leon PushkaMehra r Daniel Mobati Michael Peleg Charles Repa

Trauma Rich Haug, DDS, section section editor Jon Bradrick Vito Cardo Radhika Chigurupati Karel deLeeuw Robert Diecidue Edward Ellis Tirbod Fattahi Rui Fernandes Edwin Granite Steven Kaltman TakashiKoyama Steward Lazow Vincent Perciaccante Gary Schween Robert Strauss Joseph Van Sickels Brent Ward Dennis-Duke Yamashita Malcolm Zola


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1.

Alignment of which of the following is the the most reliable for proper reduction of the zygomaticomaxillary complex fracture? A. B. C. D.

Frontozygomatic suture Sphenozygomatic suture Infraorbital rim Medial orbital rim

Answer:

B

Rationale: The sphenozygomatic suture area has been previously analyzed and shown shown to be an area for confirmation of alignment of the zygomatic arch and the zygomatic complex (ZMC). This has also been shown to key point for fixation thru biomechanical studies. The sphenozygomatic suture is a broad area along the greater wing of the sphenoid and can be approached along the internal aspect of the lateral orbit. Even in severe midface fractures the greater wing of the sphenoid is intact thus acting as a key landmark for proper reduction of the ZMC fracture. Reduction of the frontozygomatic suture or the infraorbital rim alone can result in errors due to the small surface area. The medial orbit is generally not involved in a ZMC fracture. fracture.

Reference: Rohner D, Tay A, Meny CS, Hutmacker DW, Hammer B.: The sphenozygomatic suture as a key site for osteosynthesis of the orbitozygomatic complex in panfacial fractures: A biomechanical study in human cadavers based on clinical practice. Plast Reconstr Surg 110: 1463, 2002. Manson PN, Clark N, Robertson B, et al. Subunit principles in midface fractures: the importance of sagittal buttresses, soft tissue reductions and sequencing treatments of segmental fractures. Plast Reconstr Surg 103: 1287, 1999.


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2.

When the medial canthal ligament is attached to a bony segment in naso-orbito-ethmoidal(NOE) fracture repair the transcanthal wire is best placed: A. B. C. D.

after all soft tissue injuries have been addressed. anterior to the original insertion of the canthal ligament. posterior and inferior to the original insertion. posterior and superior to the original insertion.

Answer:

D

Rationale: The purpose of the trans-canthal wire is to secure the canthal ligament and boney segment in the pretraumatic position. Pull of the soft tissues displaces the bone and canthal ligament in an an anterior and inferior direction. Therefore a wire placed posterior and superior to the original insertion provides a vector whose resistance to displacement is most ideal and provides the best alignment.

Reference: OMS Knowledge Update, Volume three, Section 6. Abubaker AO and Strauss RA, eds. p TRA 75-76. Classification D - Trauma - Soft tissue tissue Oral and Maxillofacial Surgery InTraining Examination (OMSITE) questions for the Trauma Section.


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3.

A 21-year-old female is an unrestrained driver involved in a MVA. She suffers a scalp laceration and is noted to have lost 1000mL of blood at the scene. You would expect her vital signs to be consistent with: A. B. C. D.

Pulse rate >100, normal systolic blood pressure, decreased pulse pressure, respiratory rate of 20-30, urinary output of 20-30mL/hr. Pulse rate <100, normal systolic blood pressure, normal or increased pulse pressure, respiratory rate of 14-20, urinary output of >30mL/hr. Pulse rate >120, decreased systolic blood pressure, decreased pulse pressure, respiratory rate of 30-40, urinary output of 5-15mL/hr. Pulse rate >140, decreased systolic blood pressure, decreased pulse pressure, respiratory rate of >35, urinary output that’s negligible.

Answer:

A

Rationale: These findings are consistent with a Class II hemorrhage, 750-1500ml, The vitals signs or such a blood loss are consistent consistent with those in response response A. Response D reflects the vital signs of a Type IV blood loss, Response C a Type III and Response B a Type I.

Reference: 1997 ATLS for Doctors, Sixth Edition.


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4.

A 65-year-old man fell down the stairs. Upon examination of him, you notice that he opens his eyes to speech, localizes pain, and mutters inappropriate words. You assess his Glasgow coma scale (GCS) to be: A. B. C. D.

13 11 9 7

Answer:

B

Rationale: According to the Glascow Coma Scale, the patient can open his eyes in response to commands speech, (3 out of 4); localizes pain, (5 out of 5); yet y et produces inappropriate words, (3 out of 6); for a Glascow coma score of 11.

Reference: 1997 ATLS for Doctors, Sixth Edition


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5.

A 79-year-old 79-year-old white male presents presents to to your office for for removal removal of carious teeth. Medical history history review reveals chronic obstructive pulmonary disease (COPD), hypertension, peptic ulcer disease, athlerosclerosis with with occasional angina, and osteoarthritis. osteoarthritis. Daily medications include isosorbide dinitrate, furosemide, and acetaminophen. After conscious sedation sedation with midazolam midazolam and local anesthesia with prilocaine, you note that in recovery he has slowly become ashen looking and the pulse oximetry reading has fallen to 85%. Which of the following measures is most appropriate? A. B. C. D.

Intubation and hyperventilation with 100% oxygen Titrated administration of 0.4 mg flumazenil IV Methylene blue administration 1 mg/kg IV Assisted ventilation by face mask with room air.

Answer:

C

Rationale: This situation may appear to be pulmonary in origin, but in fact represents acquired methemoglobinemia. This condition can be precipitated by nitrates, nitrates, (such as isosorbide dinitrate) acetaminophen, prilocaine, articaine, and a number of other medications, especially in genetically susceptible individuals. The oxidized (ferric) state of the methemoglobin molecule cannot be reversed by increasing the FIO2, which also may decrease the respiratory drive in COPD. Sedation reversal by flumazenil will will have no effect on the condition. Cautious administration of methylene blue will reduce methemoglobin back to a ferrous state, normalizing the oxygen binding/delivering capacity of hemoglobin.

Reference: th Benumof JL Anesthesia & Uncommon Diseases, 4 ed. WB Saunders, 1998 pp288-9


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6.

When performing a z-plasty to remove a prominent labial frenum the secondary incisions are made at an angle approximately 60 degrees to allow the main limb to be rotated: A. B. C. D.

33 degrees 45 degrees 60 degrees 90 degrees

Answer:

D

Rationale: A z-plasty is designed to rotate the frenum or scar 90 degrees. Secondary incisions made at other angles may not allow as great a rotation of the main limb (in this case, the main frenum incision) as those made at 60 degrees tothe main limb.

Reference: Fonseca, RJ, Oral and Maxillofacial Surgery Vol 7, Reconstruction and Implant Surgery, WB Saunders 2000


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7.

When performing a floor-of-the-mouth lowering procedure, it is necessary to: A. B. C. D.

perform a subperiosteal dissection cover the denuded region with a soft tissue graft avoid altering muscle attachments in patients diagnosed with retrolingual sleep apnea detach all muscle attachments at the genial tubercle

Answer:

C

Rationale: Patients with suspected or diagnosed obstructive sleep apnea should not have muscle attachments altered in floor-of -mouth lowering procedures because this may worsen or create obstruction. Supraperiosteal dissections are performed and the incision margin is sutured to the periosteum at the depth of the vestibule. It is not necessary to place a soft tissue graft over the denuded periosteum as this may be allowed to secondarily epithelialize. The genioglossus muscle attachments at the genial tubercle may be partially removed to increase the lingual sulcus, but approximately ½ of the genioglossus attatchment should remain intact to ensure proper tongue function.

Reference: Fonseca RJ Oral and Maxillofacial Surgery Vol. 7 p. 49WB Saunders2000


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8.

A mandibular angle fracture with comminution, infection, or loss of bone buttressing is best treated with which type of fixation: A. B. C. D.

miniplate. dynamic compression plate (DCP). reconstruction plate. wire osteosynthesis.

Answer:

C

Rationale: The need for absolute stability for these types of fractures negates wire or miniplate fixation. DCP causes interfragmentary compression with possible bone devitalization and necrosis. The reconstruction plate is specifically indicated in these instances.

Reference: Ellis- Treatment of mandible angle fractures using AO reconstruction plates.JOMS1993;51(3):250-254.


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9.

Which of the following medications may trigger asthmatic symptoms? A. B. C. D.

Atropine Ipatropium Valdecoxib Isoetharine

Answer:

C

Rationale: Valdecoxib (Bextra) is a cyclo-oxygenase-2 inhibitor. Any inhibitor of prostaglandin synthesis (such as nonsteroidal anti-inflammatory drugs) can cause an increase in leukotrienes which cause bronchoconstriction. Atropine, being an anticholinergic, was formerly used to decrease bronchoconstriction in asthma but is no longer used because of its systemic side effects. Ipatropium bromide(Atrovent) is an inhaled anticholinergic used in chronic refractory asthma and in chronic obstructive pulmonary disease. Isoetharine (Bronkosol) is an inhaled B2 agonist used for bronchodilation as a nebulized solution.

Reference: th Washington Manual of Medical Therapeutics 28 ed., Little Brown, 1995 pp. 238-242


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10. Which of the following would be observed in a patient with an isolated C4-5 spinal cord injury? A. B. C. D.

Disturbance of heart rate Apnea A major loss of diaphragmatic function An air embolism

Answer:

C

Rationale: The phrenic nerve innervates the diaphragm and arises from cervical segments 3, 4, and 5. Therefore, a cervical spine injury at this level would likely cause severe ventilatory dysfunction, affecting tidal volume, vital capacity, or FEV1. A is incorrect, since parasympathetic innervation to the heart arises from Cranial Nerve X and the sympathetic innervation arises from the cervical sympathetic trunk, and both join to form the cardiac plexus. B is incorrect, since the injury only involves C4-5 (and not C3); the phrenic nerve would probably still be somewhat functional, and some ventilation would be expected. D is incorrect. This is a completely random answer, not necessarily related to this injury.

Reference: Hollingshead's Manual of Practical Anatomy


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11. A 16-year-old male is involved in a motor vehicle accident. He is found unresponsive at the scene and is intubated and brought to the emergency room. On arrival he both opens his eyes and withdraws only to painful stimulus. What is his Glascow Coma Scale classification? A. B. C. D.

4T 5T 6T 7T

Answer:

C

Rationale: Intubated patients receive a 'T' since they are unable to verbally respond Best Eye Response. (4) No eye opening. Eye opening to pain. Eye opening to verbal command. Eyes open spontaneously. Best Verbal Response. (5) 1. No verbal response 2. Incomprehensible sounds. 3. Inappropriate words. 4. Confused 5. Orientated Best Motor Response. (6) 1. No motor response. 2. Extension to pain. 3. Flexion to pain. 4. Withdrawal from pain. 5. Localising pain. 6. Obeys Commands.

Reference: ATLS Manual, 1997


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12. When utilizing the Champy technique for fixation of a mandibular angle fracture, the plate used for fixation is: A. B. C. D.

an eccentric dynamic compression plate. placed in the zone of compression. placed in the zone of neutrality. placed in the zone of tension.

Answer:

D

Rationale: The principle of the Champy technique is for fixation in the zone of tension with natural functional forces aiding in the approximation of the fracture in the area of compression.

Reference: Champy M, Lodde JP, Scmitt R, et al. Mandibular osteosynthesis by miniature screwed plates via a buccal approach. Journal of Maxillofacial Surgery 1978; 6:14-9.


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13. When utilizing a retromandibular approach to a subcondylar fracture, which of the following is true? A. B. C. D.

The dissection can go behind or through the parotid gland The dissection goes between the temporal and zygomatic branches of the facial nerve The approach is best for subcondylar fractures that are high The superior extent of the incision begins 2 cm below the earlobe

Answer:

A

Rationale: Dissections posterior to the parotid and through the parotid have been described. Classically the dissection carried between the cervicofacial trunk and the temporofacial trunk of the facial nerve. The dissection may be on either side of the marginal mandibular branch. This approach is best for lower subcondylar fractures and more limited for higher fractures. The incision begins approximately 0.5 cm below the earlobe.

Reference: Hinds EC: Correction of prognathism by subcondylar osteotomy. J Oral Maxillofac Surg 16:209, 1958 Ellis E III, Zide MF: Surgical Approaches to the Facial Skeleton. Baltimore. Lippincott Williams & Wilkins. 1995


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14. When performing a Risdon approach to a mandibular angle fracture: A. B. C. D.

posterior to the facial artery the marginal mandibular branch of the facial nerve is always located below the inferior border of the mandible. posterior to the facial artery the marginal mandibular branch of the facial nerve may drop 2.5cm below the inferior border of the mandible. anterior to the facial artery the marginal mandibular branch of the facial nerve is found below the inferior border of the mandible less than 10% of the time. anterior to the facial artery the marginal mandibular branch of the facial nerve usually has only one branch.

Answer:

C

Rationale: The two classic articles on this subject quote incidences of 0% and 6% frequency of the marginal mandibular branch of the facial nerve being found below the inferior border of the mandible anterior to the facial artery. Posterior to the facial artery, 19% of the time the marginal mandibular branch of the facial nerve may be located below the inferior border of the mandible up to 1 (or1.2) cm. Anterior to the facial artery the marginal mandibular branch of the facial nerve has one branch only 21% of the time.

Reference: Ziarah HA. Atkinson ME. The surgical anatomy of the mandibular distribution of the facial nerve. [Journal Article] British Journal of Oral Surgery. 19(3):159-70, 1981 Se p Dingman R, Grabb W: Surgical anatomy of the mandibular ramus of the facial nerve based on the dissection of 100 facial halves. Plast Reconstr Surg 29:266-272, 1962


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15. When treating uncomplicated, compound mandible fractures, the current recommendation for antibiotics is that: A. B. C. D.

antibiotic coverage is not needed. perioperative antibiotic use is indicated. pre-op antibiotics with a 7 day post-operative course are indicated. antibiotics are only useful for open reductions.

Answer:

B

Rationale: Compound or open mandible fractures have been shown to have reduced infection rates when perioperative antibiotics have been used. The use of postoperative courses of antibiotics has not been shown to affect the rate of infection.

Reference: Zallen RD, Curry JT:A study of antibiotic usage in compound mandibular fractures. J Oral Surg; 33:431, 1975. Abubaker AO, Rollert MK:Postoperative antibiotic prophylaxis in mandibular fractures:A preliminary randomized double-blinded and placebo controlled clinical study. J Oral Maxillofac Surg; 59:1415, 2001.


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16. Surgical exposure of which of the following areas would require soft tissue re-suspension to reestablish facial form? A. B. C. D.

Midface exposure via an oral vestibular incision Symphysis exposure via submental incision Zygomatic exposure via coronal incision Orbital floor exposure via transconjunctival incision.

Answer:

C

Rationale: Extended exposure of the facial skeleton is indicated for management of many complex facial fractures. Re-suspension of the soft tissue is important to establish proper facial form. Midface exposure via vestibular incision avoids key suspensory areas, thus simple closure is usually indicated. Symphysis exposure via a submental incision leaves the origin of the mentalis muscle attached to the surround soft tissue and/or bone. Re-suspension via this approach is not indicated. With exposure of the orbital floor via a transconjunctival incision simple closure is all that is indicated. When the zygomatic process is exposed via a coronal approach the superficial layer of the temporalis fascia is incised and periosteum overlying the arch is detached. This can result in ptosis of the suborbicularis oculi fat pad. This fat pad must be re-suspended to the lateral orbit.

Reference: Manson PN, Clark N, Roberston B, et al Subunet Principles in Midface Fractures:The Importance of Sagittal Buttresses, Soft Tissue Reductions and Sequencing Treatment of Segmental Fractures. Plast Reconstr Surg 103:1287-1306, 1999.


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17. Which of the following is the treatment of choice in management of bilateral mandibular body fractures in a patient with an extremely atrophic mandible (less than 6 mm of bone height)? A. B. C. D.

Closed reduction with a gunning splint Lag screw fixation of the mandibular segments Fixation with mini plates Fixation with reconstruction plates

Answer:

D

Rationale: In order to allow healing of a fracture of the atrophic mandible, the fixation technique must neutralize the tension forces on the mandible. The only fixation technique that satisfies these criteria is the use of a reconstruction plate.

Reference: Sikes JW, Smith BR, Mukherjee DP. An In-Vitro Study of the Effect of Bony Buttressing on Fixation Strength of a Fractured Atrophic Edentulous Mandible Model J Oral Maxillofacial Surgery 58:56-61, 2000.


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18. A patient presents with a displaced inner and outer table frontal sinus fracture with associated CSF leak. There is no involvement of the nasofrontal drainage system. Which of the following procedures is indicated for the management of the frontal sinus? A. B. C. D.

Open reduction and internal fixation of the inner and outer table of the frontal sinus Obliteration of the frontal sinus with preservation of the nasofrontal drainage system Cranialization of the frontal sinus with obliteration of the nasofrontal draining system Obliteration of the frontal sinus with obliteration of the nasofrontal drainage system

Answer:

C

Rationale: Fracture of the inner and outer table of the frontal sinus with communition and CSF leak represent the most complex of frontal sinus injuries. The dual tears associated with the frontal sinus leak must be repaired and they are usually approached via a coronal incision with the removal of a portion of the frontal bone. With communition of the posterior table ORIF of these fractures would be difficult. Because of the rapid growth of respiratory mucosa any and all remnants of epithelium within the sinus must be removed and the bony walls curetted to remove any epithelium remnants. Obliteration of the sinus is indicated when there is an intact posterior sinus wall. This allows for maintenance of the material used for obliteration to remain within the sinus cavity. In all cases of obliteration of the frontal sinus, obliteration of the nasofrontal ducts is also indicated to preve nt respiratory microflora from entering into this cavity or entering into the sinus, thus preventing infection. In this case, due to the fracture of the inner and outer table of the frontal sinus with associated CSF leak, all of the posterior table should be removed to allow for expansion of the frontal lobes into the residual cavity. The outer table is reconstructed in this procedure. In all cases of cranialization of the frontal sinus, the nasofrontal drainage system is obliterated.

Reference: Rohrich RJ, Hollier LH. Management of Frontal Sinus Fractures; Changing Concepts. Clinics in Plastic Surgery 19:219-232:1992.


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19. Penetrating trauma located just above the clavicles would be an injury to what zone of the neck? A. B. C. D.

Zone 1 Zone 2 Zone 3 Zone 4

Answer:

A

Rationale: The zones of the neck were originally described by Dr. Monson in 1969. Zone 1 is defined as the area from the clavicles to the cricoid cartilage. The risk of injury to the great vessels is common in this area. Zone 2 represents the area from the cricoid cartilage to the angle of the mandible. It is the largest area of the neck and thus is most likely to be injured with penetrating neck trauma. Zone 3represents the region from the angle of the mandible to the base of the skull. The area presents the most difficult area for surgical access.

Reference: Reference:Monson DO, Saletta JD, Freeark RJ. Carotid Vertebral Trauma. J Trauma 9:98799, 1969.


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20. At what distance behind the superior aspect of the medial orbital rim would the anterior ethmoidal foramen and its associated artery be located? A. B. C. D.

0 to 5 mm 10 to 15 mm 20 to 25 mm 30 to 35 mm

Answer:

C

Rationale: The anterior and posterior ethmoidal arteries will require identification when performing medial orbital wall or roof dissections. The vessels may also be identified for ligation in order to control nasal bleeding. The anterior ethmoidal foramen transmits the anterior ethmoidal artery and anterior ethmoidal branches from the nasociliary nerve. The posterior ethmoidal foramen transmits the posterior ethmoidal artery and the spheno-ethmoidal nerve from the nasociliary nerve. These foramina can be located posterior to the junction of the medial orbital wall and orbital roof. The anterior ethmoidal foramen is located twenty to twenty-five millimeters behind the medial orbital rim and the posterior ethmoidal foramen is located twelve millimeters posterior to this point or approximately thirty-two to thirty-seven millimeters.

Reference: Ochs MW. Orbital and Ocular Trauma. Miloro M (Ed):Peterson's Principals of Oral and Maxillofacial Surgery, Second Edition. BC Decker, Inc. Hamilton, Ontario 2004. p. 465


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22. A 9-year-old child is brought to the emergency room after being struck by a car. The patient is unresponsive to command and breathing only infrequently. Cervical immobilization is in place. Oral intubation attempts are unsuccessful because of brisk bleeding from facial fractures. The most appropriate next step is: A. B. C. D.

obtain an angiogram surgical cricothyroidotomy. surgical tracheostomy. percutaneous tracheostomy.

Answer: B & C Rationale: The child is too young for cricothyroidotomy and percutaneous tracheostomy is not indicated for emergency airway. Cricothyroidotomy is not recommended in children less than 12 years of age, since the cricoid cartilage is the only circumferential support to the upper trachea. ATLS teaches that a child may be temporarily oxygenated with needle jet insufflation, but this technique does not provide ventilation and is not a definitive airway. Although surgical tracheostomy is unappealing in this age category, it is the procedure of last resort in this scenario.

Reference: th Advanced Trauma Life Support for Doctors Course Student Manual, 7 E d., First Impression Press, 2004, page 48,49,250


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23. An adult patient has a self-inflicted shot gun wound to the mouth. He is brought to the emergency room intubated with a large facial wound. Vital signs upon arrival are heart rate 130, respiration 35, and blood pressure 90/60. The patient is fighting restraints. A urinary catheter insertion produced only 10 cc of urine. Which of the following Class of hemorrhage and initial resuscitation treatment is correct? A. B. C. D.

Class II. Treat with crystalloid solution Class III. Treat with blood transfusion Class III. Treat with crystalloid solution and blood transfusion Class IV. Treat with crystalloid and blood transfusion.

Answer:

C

Rationale: Class III hemorrhagic shock is characterized by tachycardia, tachypnea, mental status changes and measurable fall in systolic blood pressure, but without the significant narrowing of pulse pressure seen in Class IV shock. Also the tachycardia and tachypnea are worse in Class IV shock. Lactated Ringers or 0.9% normal saline is the fluid of choice for initial resuscitation. Given excessive hemorrhage, >20%, red blood cells should be replaced to maintain oxygen carrying capacity. Cross-matched is the ideal choice, but time constraints (30 min) may require Type-specific blood (5-15 min) to be used.

Reference: th Advanced Trauma Life Support for Doctors Course Student Manual, 7 E d., First Impression Press, 2004, page 75 nd Miloro M, et al. Peterson's Principles of Oral and Maxillofacial Surgery, 2 Edition. Pg 343. BC Decker Inc, 204.


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25. When opening a subcondylar fracture through a retromandibular approach: A. B. C. D.

the patient should be paralyzed . the forehead should always be in view in the surgical field. the closure of the parotid capsule/SMAS and platysma layer is critical to minimize occurrence of a salivary fistula. the local anesthesia should be injected deep to the platysma muscle.

Answer:

the

C

Rationale: Salivary-cutaneous fistulae are potential sequelae to the retromandibular approach. To help avoid this complication it is recommended that a “water tight” closure be performed.

Reference: Ellis E. Zide M. Surgical Approaches to the Facial Skeleton Williams and Wilkins, Media, PA, 1995


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27. Intravenous fluids administered to a patient with acute brain injury should be: A. B. C. D.

hypotonic. hypertonic. normotonic. glucose-containing.

Answer:

C

Rationale: Intravenous fluids administered to acutely brain-injured patients should normotonic in order to maintain normovolemia. Hypovolemia and hypervolemia is harmful to these patients. Hyperglycemia from use of glucose-containing fluids is harmful to the injured brain. Normal saline or Ringer's lactate is recommended for resuscitation. Serum sodium levels need to be monitored to prevent hyponatremia which can lead to brain edema.

Reference: th Advanced Trauma Life Support for Doctors. Student Course Manual, 7 Edition, p.165. American College of Surgeons 2004.


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28. Regarding blunt force trauma to the midface, which of the following anatomic structures can be considered a pillar of support that can resist compression and deformation? A. B. C. D.

Anterior maxillary sinus wall Posterior maxillary sinus wall Zygomatico-maxillary junction Zygomatico-sphenoid junction

Answer:

C

Rationale: There are three vertical buttresses of the midface:zygomatico-maxillary, pterygo-maxillary, and naso-maxillary. These structures consist of thicker supporting regions of bone that transmit and/or resist forces to the base of the skull. The horizontal buttresses of the midface are the (1) pyriform aperture, (2) maxillary alveolus and palate, (3) orbital rims and (4) base of the skull.

Reference: Fonseca, RJ, Oral and Maxillofacial Trauma Vol 1, Advances in Maxillofacial Trauma Surgery, Elsevier 2005. Manson P, et al. Plastic and Reconstructive Surgery. Structural Pillars of the Facial Skeleton:An Approach to the Management of Le Fort Fractures. July 1980, 66(1) pg. 57.


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29. Stabilization of the medial canthal tendon during a medial canthopexy should be directed at which of the following directions? A. B. C. D.

Anterior and superior Anterior and inferior Posterior and superior Posterior and inferior

Answer:

C

Rationale: Repair of detached medial canthal tendons during a severe naso-orbital ethmoidal fracture repair involves reattachment of one or both tendons to the posterior lacrimal crest in a slightly posterior and superior direction to overcome the forces of migration, relapse, and telecanthus.

Reference: Fonseca, RJ, Oral and Maxillofacial Trauma Vol 2, Diagnosis and Treatment of Midface Fractures, Elsevier 2005


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31. An injury to the temporo-facial trunk of the facial nerve is suspected within a deep cheek laceration. Which of the following will best confirm an intact a nd functioning facial nerve? A. B. C. D.

A normal Bell’s phenomenon An intact corneal reflex Absence of divergent strabismus Absence of an oculo-cardiac reflex

Answer:

B

Rationale: Integrity of the temporo-facial trunk of the facial nerve can be assessed by performing a corneal reflex (tearing to touching the ipsilateral cornea.) The afferent and efferent limbs of the reflex involve the first division of the trigeminal nerve and facial nerve respectively. Strabismus is associated with defects in cranial nerves III, IV, and VI.

Reference: Bates, B, A Guide to Physical Examination and History Taking, The Nervous System, JB Lippincott 2002


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32. Which of the following would be an indication for frontal sinus obliteration? A. B. C. D.

Non-displaced greenstick fracture of the anterior table. Fracture of the posterior table. Nasofrontal duct occlusion. Nasolacrimal duct damage.

Answer:

C

Rationale: Displaced anterior table fractures should be opened with careful inspection of the sinus mucosa. A non-displaced posterior table fracture without CSF leak can be managed without obliteration of the frontal sinus. Occlusion of the nasofrontal ducts requires removal of all sinus mucosa from the frontal sinus, inversion of the mucosa into the ducts, and elimination of dead space. This eliminates the possibility of developing a hematoma or seroma. Fat has been historically used with most success; no filler, hydroxyapatite, glass wool, bone, cartilage, muscle, absorbable gelatin sponge and fabric, acrylic have also been used.

Reference: nd Miloro M, et al. Peterson's Principles of Oral and Maxillofacial Surgery, 2 Edition. Pg 496-501. BC Decker Inc, 204.


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33. Which of the following surgical approaches to the inferior orbital rim has the least potential for producing post-operative ectropion and poor cosmesis? A. B. C. D.

Infraorbital Subciliary Transconjunctival Inferior Lid

Answer:

C

Rationale: Infraorbital or rim incision results in the worst esthetics and offers no advantages. The subciliary incision has an ectropion rate of approximately 6 %, whereas the transconjunctival incision has an ectropion/entropion rate of approximately 1.2 %. Thus, the transconjunctival incision as the approach of choice to avoid ectropion.

Reference: nd Miloro M, et al. Peterson's Principles of Oral and Maxillofacial Surgery, 2 Edition. BC Decker Inc, 2004.


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34. Which of the following is the most common early complication related to frontal sinus trauma? A. B. C. D.

Mucocele formation Brain abscess Mucopyocele formation Meningitis

Answer:

D

Rationale: All of the above cited answers are potential complications to frontal sinus fractures. Meningitis is the most common EARLY complication. The remainders of the answers are delayed or late potential complications. Frontal sinus complications can occur many years after injury (often greater than 20 years after injury). The most serious complications: can include displacement of the frontal bone in the brain and floor of frontal sinus into the orbit. Infectious complications, such as meningitis or intracranial abscess occur via ba cterial spread through posterior table fractures or the diploe veins of Behçet; or by osteomyelitis, or mucocoele formation. Mucoceles are the most common chronic complication with diagnosis made via CT scanning. Periodic review by CT should be done every 1, 2 and 5 years following surgery. Symptoms include headache and can include loss of smell (anosmia.).

Reference: Fonseca, RJ, Oral and Maxillofacial Trauma, Third Edition, 2005, Vol 2, pp 731-32. Miloro nd M, et al. Peterson's Principles of Oral and Maxillofacial Surgery, 2 Edition. Pg 503. BC Decker Inc, 204.


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36. A comminuted angle fracture of the mandible would be treated most effectively with the following fixation: A. B. C. D.

ORIF with reconstruction bone plate applied to the inferior border with 3 bone screws on each side of the fracture. antibiotics and soft diet for 4 weeks. anatomic reduction with Champy bone plate at the superior border. maxillo-mandibular fixation to restore occlusion for 4 weeks.

Answer:

A

Rationale: The reconstruction plate is designed to bear the entire load of the mandibular movement across the fracture site. The remaining methods mentioned do not adequately stabilize the fracture segments and increase the possibilities for non-union and infection.

Reference: Miloro, M. et al, Peterson's Principles of Oral and Maxillofacial Surgery, 2 375, BC Decker INC, 2004


nd Edition, page

34

37. The best technique to manage a 40% traumatic avulsion of the upper eyelid is: A. B. C. D.

allow the wound to heal by secondary granulation. undermine and close primarily. split thickness skin graft from the ipsilateral postauricular region. full thickness skin graft harvested via blepharoplasty approach from the contralateral upper eyelid.

Answer:

D

Rationale: Full thickness skin graft from the opposite upper lid is preferred due to similar skin thickness, color, texture and availability with minimal donor site morbidity. This avo ids scar and ectropion.

Reference: Sandler NA, Evaluation and management of traumatic eyelid injury, OMS Knowledge Update vol 3, AAOMS, 2001


35

38. The most predictable means to treat a large posterior auricular skin/cartilage avulsion is: A. B. C. D.

reattachment as a composite graft with hyperbaric oxygen. microvascular reimplantation. full thickness skin graft to cover exposed cartilage. 2 phase bipedicled postauricular flap.

Answer:

D

Rationale: Exposed cartilage will not accept a skin graft. Composite free auricular grafts and microvascular reanastomosis have poor success rates due to poor venous drainage. The bipedicled flap nicely and predictably reconstructs the posterior helical defect. If the avulsed segment is 1 cm or less it can be reattached and allowed to revascularize. Larger avulsive injuries, the “pocket principle” can be used where the detached ear is dermabraded and reattached to the stump and then buried under a skin flap in the posterior auricular region to provide vascular supply. 2-3 weeks later the revascularize ear is uncovered and allowed to reepithelialize.

Reference: Dierks EJ, Deeb GR, Evaluation and management of ear injuries, OMS Knowledge Update vol 3, AAOMS, 2001


36

39. Recurrent sialocoele formation after emergency room repair of a deep facial laceration is best handled by: A. B. C. D.

multiple aspirations, pressure dressings, and antisialagogues. superficial parotidectomy. reexploration of the wound, cannulation of Stensen’s duct, and repair of the parotid capsule. low dose radiation.

Answer: A & B Rationale: Sialoceoles that repeatedly reform, even after aspiration, and pressure dressings, and antisialogogues may indicate a parotid capsular or Stensen's duct injury that requires early reexploration and repair. Sialocoele formation within 48 hours can indicate an injury to the salivary ductal system and exploration of the injury is needed. The patient also needs to have antibiotic coverage with penicillin or a cephalosporin.

Reference: Fonseca RJ and Walker RV, “Management of soft tissue injuries”, Oral and Maxillofacial Trauma, vol 1, pg. 642. WB Saunders, 1991


37

40. A 5cm. full thickness scalp avulsion down to the cranium is best treated by a: A. B. C. D.

split thickness skin graft. full thickness skin graft. split thickness skin graft placed over bur holes made in the outer table. rotation-advancement flap.

Answer:

D

Rationale: Exposed cortical cranial bone will not accept skin grafts. Rotational-advancement flaps with multiple galeal releasing incisions parallel to the long axis of the flap will provide adequate coverage in most instances.

Reference: Fonseca RJ and Walker RV, Management of soft tissue injuries, Oral and Maxillofacial Trauma, vol 1, WB Saunders, 2001


38

41. Success after replantation of an avulsed tooth that was preserved in a clean and moist container by the patient is most dependent on: A. B. C. D.

sterilization before replantation. replantation within 30 minutes after avulsion. curettage of the tooth root and socket. rigidity of fixation splinting.

Answer:

B

Rationale: Optimal success of treatment is to replant and stabilize avulsed teeth within 2 hours. The PDL cells become irreversibly necrotic after this time frame. Treatment with a nonrigid splint will allow movement of the tooth, allowing the PDL to heal.

Reference: Abubaker AO, Giglio JA, Mourino AP, Diagnosis and management of dentoalveolar injuries. In:Fonseca RJ:Oral and Maxillofacial Surgery, Vol 1. W.B. Saunders Co, Philadelphia, 2000. nd Miloro M, et al. Peterson's Principles of Oral and Maxillofacial Surgery, 2 Edition. Pg 394-5. BC Decker Inc, 2004.


39

42. Failure after replantation of an avulsed tooth occurs mostly due to: A. B. C. D.

internal resorption, external resorption, pulpal necrosis. external resorption, ankylosis, periodontal disease. internal resorption, tooth migration, ankylosis. external resorption, pulpal necrosis, periodontal disease.

Answer:

A

Rationale: The most common tooth avulsed is the maxillary central incisor. Treatment is geared towards early re-establishment of the PDL cell physiology, via solutions with physiologic pH and osmolarity. Re-implant and stabilize the tooth within two hours of avulsion.

Reference: Abubaker AO, Giglio JA, Mourino AP, Diagnosis and management of dentoalveolar injuries. In:Fonseca RJ:Oral and Maxillofacial Surgery, Vol 1. W.B. Saunders Co, Philadelphia, 2000. nd Miloro M, et al. Peterson's Principles of Oral and Maxillofacial Surgery, 2 Edition. Pg 393-395. BC Decker Inc, 2004.


40

43. Generally speaking, soft tissue injuries associated with dentoalveolar trauma are treated: A. B. C. D.

before management of all hard tissue injuries. after management of all hard tissues injuries. before management of bony injuries, but after management of dental injuries. should never be closed primarily but should be allowed to heal by secondary intention.

Answer:

B

Rationale: Soft tissue wounds associated with dentoalveolar trauma are always treated after management of the hard tissue. This prevents wasting time of suturing wounds that are likely to be removed or compromised during the intraoral manipulation to treat the hard tissue or dental injuries.

Reference: nd Peterson LJ, Contemporary Oral and Maxillofacial Surgery, 2 edition, Ed. Pg. 583. JB Lippincott Co., Philadelphia 1992


41

44. In order to avoid irreversible vision loss, an orbital fracture associated with optic nerve compression must be addressed within which length of time? A. B. C. D.

24 hours 36 hours 4 hours 2 hours

Answer:

D

Rationale: The retina is an extension of the brain, and will have similar reaction in the presence of ischemia. Signs and symptoms of visual impairment, severe o cular pain should be evaluated for retrobulbar hematoma. Computed tomography eva luation can demonstrate signs of retrobulbar hematoma formation, but immediate treatment with a lateral c anthotomy based on clinical symptoms and signs should be completed prior to a lengthy CT scan. Other signs of optic nerve compromise include (1) afferent papillary d efect (2) visual field loss and (3) color vision defects.

Reference: Girotto JA, Gamble WB, Robertson B, et al, Blindness After Reduction of Facial Fractures, Plast Reconstr Surg 102:1821, 1998. nd Miloro M, et al. Peterson's Principles of Oral and Maxillofacial Surgery, 2 Edition. Pg 472. BC Decker Inc, 204.


42

45. After surgical treatment of a zygomaticomaxillary complex fracture, the immediate treatment of a retrobulbar hematoma accompanied by loss of visual acuity and increased intraocular pressure is: A. B. C. D.

decompression of the frontal sinus. intravenous corticosteroids. lateral canthotomy. medial canthotomy.

Answer:

C

RATIONALE: The emergency procedure of choice for acute visual acuity loss associated with acute orbital compartment syndrome is dissection of the lateral canthus and disinsertion of at least the inferior crus of the lateral canthal tend on, which allows complete mobility of the lower lid. Visual loss without clear signs consistent with increased IOP is not an indication for this procedure. Other primary indications for lateral canthotomy and cantholysis include an IOP greater than 40 mm Hg and proptosis, which may be used as a criterion for unconscious patients whose visual acuity cannot be determined. Secondary criteria include afferent pupillary defect, ophthalmoplegia, cherry-red macula, optic nerve head pallor, and severe pain, but these are all considered less sensitive or very late signs. Contraindication for this procedure would be a suspected ruptured globe. REFERENCE: Fonseca, RJ, Walker, R, Oral and Maxillofacial Trauma Volume 1, WB Saunders, 1991


43

46. To restore proper projection of facial width and orbital volume in a patient with a high energy grossly comminuted zygomaticomaxillary fracture one should: A. B. C. D.

use a Carroll- Girard screw placed transcutaneous to reduc e the fracture in a closed method. align the comminuted segments of the infraorbital rim to assure proper placement of the zygoma. expose the sphenozygomatic suture to aid in anatomic reduction. expose and plate the zygomatic-frontal suture area before exposing other areas of the zygoma.

Answer:

C

Rationale: A grossly comminuted zygomatic complex fracture will not be stable with a closed technique. Comminuted segments of the infraorbital rim are a poor guide to placement of the zygoma. The zygomatic-frontal suture is a poor reference for placement of the zygoma. In high energy grossly comminute fractures, the sphenozygomatic suture with its broad contact can aid in the anatomic reduction of the fracture.

Reference: Baley JS, Goldwasser MS, Management of Zygomatic complex fractures. In: Miloro M ed, Peterson's Principles of Oral and Maxillofacial Surgery Second edition BC Deker, London 2004 Chapter 23.2 pp 452


44

47. Irreversible ischemic damage to the retinal tissue secondary to pressure and hypoxia has been shown: A. B. C. D.

within 60 minutes to 2 hours following a traumatic event. avoidable by use of megadose steroids which should be initiated 48 h ours after injury. to respond better to treatment when the patient has no initial light perception. to respond better when there is penetrating trauma versus blunt trauma.

Answer:

A

Rationale: The optic nerve and retinal tissue, unlike skeletal muscle, have been shown to be extremely sensitive to pressure and hypoxia. Irreversible ischemic damage often occurs within 60 minutes and certainly within 2 hours. Megadose steroids have been recommended during the first 8 hours following injury. The outcome in patients with traumatic optic neuropathy with no light perception on presentation is a poor prognostic factor. Likewise patient presenting with traumatic optic neuropathy after penetrating trauma have a worse prognosis than those with blunt facial trauma.

Reference: Wang BH, Robertson BC, Girotto JA, Liem A, Miller NR, Iliff N, Manson P, Traumatic optic neuropathy: A review of 61 patients. Plastic Reconstructive Surg 2001; 107:1653-1664


45

48. Rebleeding following a traumatic traumatic hyphema: A. B. C. D.

is associated with the use of topical cycloplegics. can be prevented by increasing intraocular pressure. may occur in 5 to 30% of patients. is increased with the use of carbonic anhydrase inhibitors.

Answer:

C

Rationale: The management of a patient with a traumatic hyphema is to use topical cycloplegics and carbonic anhydrase inhibitors to decrease intraocular pressure. Rebleeding can occur in 530% of the patients with hyphema.

Reference: Baley JS, Goldwasser MS, Management of Zygomatic Zy gomatic complex fractures. In:Miloro M ed, Peterson's Principles of Oral and Maxillofacial Surgery Second edition BC Deker, London 2004 Chapter 23.2 pp 459


46

49. An afferent pupillary defect in the presence of a normal normal eye: A. B. C. D.

is diagnosed when the pupil reacts to direct stimulation but shows a noticeably more brisk consensual response when the contralateral pupil is directly tested. indicates a normal optic nerve in the involved eye. has a different response than a Marcus Gunn Gun n pupil. is associated with pupil asymmetry.

Answer:

A

Rationale: The diagnosis of an afferent pupillary defect in the presence of normal eye is when the pupil reacts to direct stimulation but shows a noticeably more brisk consensual response when the contralateral pupil is directly directly tested. It indicates an optic nerve injury. An afferent pupillary defect is also call a Marcus Gunn pupil. Pupillary symmetry is not affected by the afferent pupil defect. This implies an efferent lesion or an iris lesion lesion or both.

Reference: Gossman MD, Roberts DM, Barr CC, Ophthalmic aspects of orbital injury; A comprehensive diagnostic and management approach. Clin Plastic Surg 1992; 19:17-85


47

50. A CT scan reveals an orbital fracture with a trap trap door appearance with clinical and radiographic eidence of inferior rectus muscle incarceration is: A. B. C. D.

more likely to occur in adults adu lts than in children. warrants early intervention to free up the tissues. can be managed by steroids and delay of surgery for 3 weeks frequently requires the use of an orbital implant to bridge the floor defect.

Answer:

B

Rationale: A CT scan of an orbit that has a trapdoor appearance with clinical and radiographic evidence of inferior rectus muscle incarceration is more like to occur in children than in adults and it warrants early intervention to prevent ischemic necrosis to the the rectus muscle. Steroids are may be used in cases where there is no evidence of muscle entrapment and mild restricted motility. By its nature, a trapdoor defect seldom requires an implant implant to bridge a defect.

Reference: Ochs MW, Orbital and ocular trauma. In: Miloro M ed, Peterson's Principles of Oral and Maxillofacial Surgery Second edition BC Deker, London 2004 Chapter 24 pp 479


48

51. Calcium phosphate bone cement used for pediatric frontal sinus obliteration: A. B. C. D.

is an almost ideal alloplast for this application. breaks up when placed directly over dura or sinus membranes. is not replaced by bone and remains inert. is readily available and inexpensive.

Answer:

B

Rationale: While calcium phosphate bone cement is a near ideal alloplast in that it has unlimited availability, is biocompatible, has high mechanical strength, has a low risk for infection, is radiopaque and is incorporated into the bone, it does have drawbacks. It is expensive, and when placed directly over dura or sinus membranes, it breaks up and a chronic foreign body reaction ensues. This is particularly true for the pediatric population.

Reference: D'Addario M, Haug RH, Talwar R: Biomaterials for Use in Frontal Sinus Obliteration. Journal of Long-Term Effects of Medical Implants. 14: 455-465, 2004.


49

53. β2 transferrin is found only in: A. B. C. D.

cerebrospinal fluid, aqueous humor and perilymph. cerebrospinal fluid, serum and aqueous humor. cerebrospinal fluid, nasal secretions and perilymph. serum, nasal secretions and aqueous humor.

Answer:

A

Rationale: β2 transferrin is one of two major variants of iron binding transferrin glycoproteins forum in several forms of various body fluids. β2 transferrin lacks a carbohydrate side chain which increases its positive charge, permitting isolation during electrophoresis. β2 transferrin is only found in cerebrospinal fluid, aqueous humor and perilymph. Thus, with the exception of contamination by a ruptured globe, it is an ideal substance to distinguish between cerebrospinal fluid, nasal secretions and serum.

Reference: Brandt MT, Jenkins WS, Fattahi TT, Haug RH:Cerebrospinal Fluid:Implications in Oral and Maxillofacial Surgery. J Oral Maxillofac Surg. 60:1049-1056, 2002.


50

54. In the recumbent position, normal intracranial pressure is: A. B. C. D.

1 to 5 mm Hg. 8 to 12 mm Hg. 15 to 19 mm Hg. 22 to 26 mm Hg.

Answer:

B

Rationale: In the recumbent position, intracranial pressure, and thus cerebral spinal fluid pressure, is about 8 to 12 mm Hg or 110 to 150 mm H2O. Autoregulation maintains this pressure.

Reference: Brandt MT, Jenkins WS, Fattahi TT, Haug RH:Cerebrospinal Fluid:Implications in Oral and Maxillofacial Surgery. J Oral Maxillofac Surg. 60:1049-1056, 2002.


51

55. The cause of permanent visual loss subsequent to traumatic hyphema is: A. B. C. D.

elevated intraocular pressure. retinal artery spasm. traumatic mydriasis. corneal staining.

Answer:

D

Rationale: While concomitant injury has been associated with hyphema and permanent visual loss, it is not the primary cause in traumatic hyphema. Retinal artery spasm is not associated with hyphema. Both increased intraocular pressure and traumatic mydriasis are concomitant problems. Corneal staining from myoglobin is the primary cause of permanent loss of vision.

Reference: Brandt MT, Haug RH:Traumatic Hyphema: A Comprehensive Review. J Oral Maxillofac Surg. 59:1462-1470, 2001.


52

57. The differences between the child and adult respiratory apparatus are that children possess: A. B. C. D.

greater diaphragmatic breathing high lung compliance. ribs and sternum that are rigid. a low metabolic rate.

Answer:

A

Rationale: The respiratory apparatus and physiology in children differs from adults in many ways. Children have a high metabolic rate, thus a high oxygen demand and hypoxemia develops rapidly their upper airway has a smaller caliber, large soft tissues, larynx that is positioned cephalad, with a shorter trachea, and epiglottis that is short and narrow. This results in increased airway resistance, easy obstruction, difficult intubation, easy extubation. The child's ribs and sternum are compliant, and when respiratory efforts are diminished, their reserve decreases. The child relies more on diaphragatic breathing, therefore high intrathoracic pressure or abdominal distention diminishes ventilation. The child possesses low lung compliance and therefore ventilation is inefficient during respiratory distress.

Reference: American College of Surgeons Committee on Trauma:ATLS Advanced Trauma Life Support th Program for Doctors. 7 Edition, American College of Surgeons, Chicago, IL, 2004, pgs 243-262.


53

58. The circulatory system for children in trauma differs from adults in that children have a proportionally: A. B. C. D.

higher cardiac output. smaller stroke volume. equal blood volume. decreased physiologic reserve.

Answer:

B

Rationale: Children possess a higher cardiac output than adults. Under the physiologic stress of trauma, the child's stroke volume cannot increase, so that under stress proportionate increases in stroke volume cannot occur and increases in cardiac output are rate determined. Bradycardia could result in hypoxia and hypercapnia, and is ominous. The child's proportional blood volume is greater than an adult. However, the absolute blood volume and therefore tolerable absolute blood loss is less, so that minor injuries may result in blood loss which is physiologically significant. The child's blood pressure is maintained through physiologic compensation (vasoconstriction, tachycardia, myocardial contractility). This compensation may be misleading by masking volume reduction. The healthy child has an increased total systemic physiologic reserve, thus with trauma, symptoms of hypoxemia or hypovolemia may not occur until a potentially catastrophic hypovolemia has occurred.

Reference: American College of Surgeons Committee on Trauma:ATLS Advanced Trauma Life Support th Program for Doctors. 7 Edition, American College of Surgeons, Chicago, IL, 2004, pgs 243-262.


54

59. Cervical spine fractures concomitant to maxillofacial injury are most often: A. B. C. D.

“burst’ fractures. “hangman” fractures. Jefferson fractures. subluxations.

Answer:

D

Rationale: When considering maxillofacial injury and cervical spine injury, a cause and effect relationship exists between the mandible and cervical spine. There is also a relationship between neurocranial injury and mid- and upper-facial third facial injuries. Approximately one out of every fifty patients with a mandibular fracture will suffer a cervical spine fracture. The vast majority of these are subluxation injuries. When the mandible sustains a force applied to it, the reaction of the body is to move away from the force. This “twisting of the neck, when accentuated, results in a subluxation injury of the cervical spine.

Reference: Haug RH, Wible RT, Likavec MJ, et al:Cervical spine fractures and maxillofacial trauma. J Oral Maxillofac Surg 49:725-729, 1991.


55

60. The difference between infected human and animal bites is the presence of: A. B. C. D.

pasteurella multocida. staphylococcus aureus. eikenella corrodens. fusobacterium nucleatum.

Answer:

A

Rationale: The human and animal population is very similar in their oral flora. Each has a predomination of Streptococcus species and numerous gram negative anaerobic organisms. Each has numerous species of viruses and some mycobacteria have been reported. It is however, Pasteurella multocida that is only found in the non-human population

Reference: Haug RH, Assael L, “Infections in the Maxillofacial Trauma Patient”, Chapter 17 in Topazian RG, Goldberg MH, Hupp J (Eds.). Oral and Maxillofacial Infections. Philadelphia PA, W B Saunders, 2002, pp 359-380.


56

61. Treatment for inflammatory fibrous hyperplasia where areas of gross tissue redundancy are present, is best treated by excision with: A. B. C. D.

electrosurgical technique. laser technique. primary closure. secondary epithelialization.

Answer:

D

Rationale: When areas of gross tissue redundancy are found, excision frequently results in total elimination of vestibule. In such cases excision of the epulides, with peripheral mucosal repositioning and secondary epithelialization, is preferred.

Reference: Ochs, MW, Tucker, MR; Preprosthetic Surgery in Peterson, Ellis, Hupp, Tucker. th Contemporary Oral & Maxillofacial Surgery 4 edition. Page 274, Mosby, 2003 USA.


57

62. Which of the following is true regarding submucosal vestibuloplasty? A. B. C. D.

A postoperative stent is essential A superiosteal dissection is performed Split-thickness skin grafts are required Commonly used in the mandible

Answer:

A

Rationale: Distortion/inversion of the upper lip when a mirror is placed to the depth of the maxillary anterior vestibule indicates a lack of vestibular depth (which is why the lip distorts). The Submucous vestibuloplasty is contraindicated in this instance. An open type vestibuloplasty with secondary skin graft or laser vestibuloplasty is a better c hoice.

Reference: Spagnoli, DB, Gollehon, SG, Misiek, DJ; Preprosthetic and Reconstructive Surgery in Peterson's Principles of Oral and Maxillofacial Surgery, Miloro, M. et al., Editors, Second Edition, BC Decker Inc, 2004, pp. 174-175


58

63. For alveolar distraction to be successful to increase alveolar ridge height and width it is imperative that the: A. B. C. D.

transport segment not be stabilized by screws to prevent resorption. periosteum be maintained on the crestal alveolus of the transport segment. transport segment be increased in size due to resorption during the process. process be completed as quickly as possible.

Answer:

B

Rationale: Distraction of the alveolus is successful only if the periosteal blood supply is maintained to the transport segment. The segment must be secured to the device to keep it stable during the process by rigid fixation. Minimal resorption of the transport segment occurs due to the intact periosteal blood supply. The process must be governed by the latency, activation, and consolidation phases and not hurried

Reference: Spagnoli, DB, Gollehon, SG, Misiek, DJ; Preprosthetic and Reconstructive Surgery in Peterson's Principles of Oral and Maxillofacial Surgery, Miloro, M. et al., Editors, Second Edition, BC Decker Inc, 2004, pp183-4


59

64. One of the most critical complications involved in genial tubercle reduction is: A. B. C. D.

over-reduction of the tubercle. under-reduction of the tubercle. partial detachment of the genioglossus muscle. hematoma of the floor of the mouth.

Answer:

D

Rationale: Reduction of the genial tubercle is performed to create an appropriate base for a denture when significant mandibular resorption has occurred. Under reduction will not provide the desired alveolar surface, over reduction may result in complete muscle detachment and difficulty swallowing for several months until reattachment occurs. The geniog lossus muscle is partially detached or may require complete detachment to adequately reduce the tubercle, it will re attach independently. Floor of the mouth hematoma may cause airway embarrassment and an emergent situation.

Reference: Spagnoli, DB, Gollehon, SG, Misiek, DJ; Preprosthetic and Reconstructive Surgery in Peterson's Principles of Oral and Maxillofacial Surgery, Miloro, M. et al., Editors, Second Edition, BC Decker Inc, 2004, pp169-170. Davis et al. Soft Tissue Procedures in Reconstructive and Preprosthetic Surgery, Fonseca and Davis Editors, Second Edition. WB Saunders Co., 1995. pp748, 759-760


60

65. Which of the following statements is true regarding alveolar distraction? A. B. C. D.

The consolidation period is the time after the osteotomy and prior to distraction Activation occurs 3mm/day in 3 divided, equal segments per day The consolidation phase should be three times the length of the active distraction period The latency period should be shortened for distraction of irradiated bone

Answer:

C

Rationale: After the osteotomy is performed and the distraction device placed, a latency period must be observed. The latency period can be from 4-7 days depending on age of patient, blood supply, irradiation to the area, scar tissue, etc. Secondary to impaired blood supply, the latency period should be longer in irradiated bone. The latency period is followed by the active distraction period which varies depending on the transport distance. The rate and rhythm of distraction is how far and how often. A rate of 1mm/day at a rhythm of .25mm four times a day is ideal. The consolidation period begins when active distraction stops and is generally three times the active distraction period.

Reference: Spagnoli, DB, Gollehon, SG, Misiek, DJ; Preprosthetic and Reconstructive Surgery in Peterson's Principles of Oral and Maxillofacial Surgery, Miloro, M. et al., Editors, Second Edition, BC Decker Inc, 2004, pp184-5


61

66. When performing a maxillary labial frenectomy where the base of the frenum is wide, the most effective surgical technique is: A. B. C. D.

extremely

Z-plasty technique. simple excision (“diamond” excision). localized vestibuloplasty with secondary epithelialization. kazanjian technique (lip switch).

Answer:

C

Rationale: Localized vestibuloplasty with secondary epithelialization has been described as the most beneficial for broad frenum attachments. The Z-plasty technique is useful when the mucosal and fibrous band is narrow. The diamond excision can result in scarring and relapse. The lip-switch is used for mandibular vestibuloplasty.

Reference: Fonseca, Davis. Reconstructive Preprosthetic Oral & Maxillofacial Surgery (1st Edition). Page 65, W.B Saunders Company, 1986 Philadelphia Ochs, MW, Tucker, MR; Preprosthetic Surgery in Peterson, Ellis, Hupp, Tucker. th Contemporary Oral & Maxillofacial Surgery 4 edition. pp 275-278, Mosby, 2003 USA.


62

68. Which of the following is more characteristic of a thin split-thickness skin graft (STSG) when compared to a thick STSG? A. B. C. D.

Increased probability of graft survival Decreased secondary contracture of the graft More likely to result in recipient site hair growth Slower donor site re-epithelialization

Answer:

A

Rationale: The thin STSG is more likely to survive on its recipient site because it can survive well during the phase of plasmatic absorption and therefore wait longer for vascularization. The thicker the graft, the less its tendency to undergo secondary contraction; full-thickness skin grafts show little or no evidence of contracture. The thicker the graft, the more likely a hair follicle will be transplanted. The thinner a graft, the more accessory skin structures remain at the donor site for epithelial growth.

Reference: Fonseca, Davis. Reconstructive Preprosthetic Oral & Maxillofacial Surgery (1st Edition). Page 35, W.B Saunders Company, 1986 Philadelphia .


63

69. The angiogenic effects of hyperbaric oxygen therapy occur at regions of: A. B. C. D.

tissue hypoxia. a shallow oxygen gradient a steep oxygen gradient tissue hyperoxia

Answer:

C

Rationale: HBO creates an oxygen gradient in radiated tissue which does not normally exist. This steep oxygen gradient stimulates the normal wound healing mechanism that is missing in radiated tissue. The effects of HBO fall off when the tissue is sufficiently revascularized so that it no longer generates a sufficient oxygen gradient to continue the angiogenic process.

Reference: Fonseca, Davis. Reconstructive Preprosthetic Oral & Maxillofacial Surgery (2nd Edition). Page 1107-08, W.B Saunders Company, 1995 Philadelphia.


64

70. When is the most appropriate time to perform a labial frenectomy to facilitate closure of a diastema between teeth numbers 8 and 9? A. B. C. D.

Prior to eruption of the maxillary lateral incisors Prior to eruption of the maxillary canines During eruption of the maxillary canines After complete eruption of the maxillary canines

Answer:

C

Rationale: Maxillary labial frenectomy should be done following the eruption of the lateral incisors and during active eruption of the maxillary canines. The combination of a correctly timed and executed maxillary frenectomy and the anterior eruption force of the maxillary canines should lead to the closure of the diastema.

Reference: Kearns, G, Pediatric Dentoalveolar Surgery in Fonseca, RJ, Oral and Maxillofacial Surgery Vol 1, Anesthesia/Dentoalveolar Surgery/ Office Management, WB Saunders 2000. pp 360361.


65

71. Which of the following statements is true regarding the Bio-Col ridge preservation technique? A. B. C. D.

Primary closure is necessary Requires use of some autogenous bone graft Should not be used in the esthetic zone Can be used with immediate or delayed implant placement

Answer:

D

Rationale: Site preservation usually begins at the time of tooth removal. In aesthetic areas, the referenced author uses the Bio-Col alveolar ridge preservation technique to preserve hard and soft tissue alveolar ridge anatomy in preparation for immediate or delayed implant placement. This technique can be used to reduce or avoid osseous ridge resorption by minimizing trauma during tooth removal. The prepared extraction sockets or the voids surrounding the immediately placed implant are then grafted with Bio-Oss (Osteohealth, Shirley, NY), a natural, porous bone-grafting material. Subsequently, the grafted socket is isolated with an absorbable collagen material (Collaplug; Zimmer Dental, Carlsbad, CA) that has been coated with an impervious tissue cement (Isodent; Ellmann International, Hewlett, NY); this allows for guided bone regeneration without the need for flap elevation and primary closure, thus preserving the surrounding soft-tissue volume. Finally, the scalloped soft tissue architecture is preserved with the use of interim provisional restorations, anatomic healing abutments, or custom tooth-form healing abutments designed to support the marginal tissues and interdental papillae. This is of critical aesthetic importance for implant patients who present with thin scalloped periodontal biotypes who are predisposed to loss of alveolar ridge volume secondary to remodeling, resorption of bone following tooth removal, and soft tissue recession following subsequent surgical or restorative interventions.

Reference: Sclar AG, Strategies for management of single-tooth extraction sites in aesthetic implant therapy. J Oral N:Maxillofac Surg. 2004 Sep;62(9 Suppl 2) 90-105. Sclar AG, Preserving alveolar ridge anatomy following tooth removal in conjunction with immediate implant placement. The Bio-Col technique. Atlas Oral Maxillofac Surg Clin North Am. 1999 Sep;7(2): 39-59.


66

72. A 48-year-old woman presents with a history of metastatic breast carcinoma, previous mastectomy, and radiation to the chest. She continues periodic chemotherapy infusions for control of her disease. Her general dentist extracted tooth #30 six weeks previous to referring the patient to you for a non-healing socket and bone exposure in the area. The most likely cause of the non-healing site is: A. B. C. D.

failure to attain primary closure at the time of extraction. osteoradionecrosis secondary to the radiation therapy. bisphosphonates included in the chemotherapy regimen. traumatic extraction with failure of the patient to follow instructed home ca re.

Answer:

C

Rationale: Bisphosphonates are widely used in the management of metastatic disease to the bone and in the treatment of osteoporosis. Recently, there is emerging evidence that these drugs are etiologically related to osteonecrosis of the jaws. Answer A is incorrect because primary closure is not possible or required. Although radiotherapy is known to be a cause of osteonecrosis, the stem of the question explicitly indicates radiation to the chest; therefore, option B is incorrect. Option D is also incorrect since even if traumatic extraction of a tooth occurred, healing should have been complete after six weeks, even without appropriate home care.

Reference: Ruggiero, S.L., Mehrotra, B., Rosenberg, T.J., and Engroff, S.L.:Osteonecrosis of the Jaws Associated with the use of Bisphosphonates:A Review of 63 cases. J. Oral Maxillofac Surg 62:527-534, 2004.


67

73. A 70-year-old diabetic man who has a history of left sinus symptoms was referred to you for extraction of erupted and loose tooth #15. Your examination revealed marked necrosis of osseous and soft tissue of the left maxilla. You removed several teeth, the necrotic bone and soft tissue, and submitted the specimen to pathology. The pathologist reported necrotic bone and soft tissue with inflammatory infiltrate and the presence of nonseptate irregularly wide fungal hyphae with frequent right- angle branching. Your diagnosis is: A. B. C. D.

Aspergillosis. Candidiasis. Actinomycosis. Mucormycosis.

Answer:

D

Rationale: The correct answer to this question requires specific knowledge of the morphology of fungi. Aspergillus forms fruiting bodies and septate filaments branching at acute angles. Candida grows as yeast forms, tandem arrays of elongated forms without hyphae (pseudohyphae), and true hyphae with septate. Actinomyces is a gram-positive filamentous or rod-shaped bacteria. Mucormycosis form nonseptate, irregularly wide fungal hyphae with frequent right-angle branching. In addition mucormycosis frequently occur in diabetics and may spread from nasal sinuses to the orbit and brain-giving rise to rhinocerebral mucormycosis.

Reference: th Regezi:Oral Pathology:Clinical Pahtologic Correlations, 4 ., 2003 Elsevier, pp 37-38. Strauss, R.A.:Fungal Infections of the Head and Neck, In:Oral & Maxillofacial Surgery Clinics of North America. Vol. 3, Number 2, W. B. Saunders 1991, pp 295-309.


68

74. During extraction of teeth #14 and #15, the two teeth were delivered with a large attached piece of the buccal alveolar plate. An 8 mm diameter oro-antral communication is noted. The most appropriate treatment course is: A. B. C. D.

attempt suturing as best as possible with available local tissue. develop a buccal mucoperiosteal flap and advance it to achieve primary closure without tension. develop a free palatal mucosa graft to passively cover the defect. immediately proceed with packing the sinus with iodoform gauze saturated with triple antibiotics and perform a nasal antrostomy.

Answer:

B

Rationale: Acute oroantral communication is a common occurrence during extraction of the posterior maxillary teeth. In most instances these perforations are small and the blood clot that fills the extraction site usually seals such small perforations. If there is an infection in the antrum, the defect is large (>5 mm in diameter), the gingival tissue are not approximated, the wound is dehisced, or the patient does not follow the postoperative instructions, an oro-antral fistula occurs. Although option A seems reasonable for a small fistula, due to the size of the defect, local suturing without flap development will most likely not result in primary closure, and then result in an oro-antral communication. Option B offers the best chance of primary closure of the large communication and prevents development of de novo sinusitis. A free graft cannot survive over a hole without its own blood supply and thus option C is incorrect. Option D is also incorrect because it treats chronic sinusitis. There is no indication in the stem of the question that sinusitis occurred. Closure of the communication is not addressed.

Reference: Laskin, D.M.:Management of Oro-antral fistula and other sinus-related complications. In:Oral Maxillofac Surg Clinic North America Vol. Number 1, Fe b. 1999, W.B. Saunders, Philadelphia, pp 155-179.


69

75. During extraction of erupted tooth #19, the mesial root tip fractures. During your attempt to elevate, the fragment disappears through the socket. The most appropriate surgical approach to retrieve the root tip is: A. B. C. D.

create a buccal flap and remove the buccal alveolar plate to gain access. develop a lingual flap. a Risdon approach. widen the cortical defect through which the root disappeared.

Answer:

B

Rationale: The mylohyoid muscle forms the floor of the mouth attaching to the mylohyoid ridge. The latter curves superiorly as it approaches the third molar. Roots of first molars are usually superior to level of mylohyoid muscle attachment to the mandible. The root tips of third molars are usually inferior to the muscle attachment. Also, the lingual plate is thin in this site. Therefore, option B is correct. Options A and D are both incorrect since extensive procedures that may not gain visualization of the displaced root, are required. Option C is incorrect because anatomically the root is likely to be superior to mylohyoid. If a third molar root was displaced, it may be inferior to the mylohyoid. In this latter situation the submandibular approach may be necessary.

Reference: Gregg, J.M.:Surgical Anatomy. In Oral and Maxillofacial Surgery, Vol. 1, edit:D.M. Laskin. The C.V. Mosby Company, St. Louis, 1980, pp 3-49. Pogrel, M.A.:Complications of Third Molar Surgery. In Oral and Maxillofacial Surgery Clinics of North America Vol 2, Number 3, 1990, W.B. Saunders Company. Pp. 441-451.


70

76. Which erupted maxillary tooth is usually associated with the highest rate of oral-antral communication after routine extraction? A. B. C. D.

Maxillary second premolar Maxillary first molar Maxillary second molar Maxillary third molar

Answer:

B

Rationale: The palatal root of the maxillary first molar is usually the most closely related to the floor of the maxillary sinus.

Reference: Alling CC (Ed). Dentoalveolar Surgery. Oral and Maxillofacial Surgery Clinics of North America. Vol 5. WB Saunders. Philadelphia, 1993


71

77. During routine extraction of a maxillary first molar with radiographic periapical pathology, a 5mm fragment of the palatal root is dislodged into the maxillary sinus. What is the most appropriate next step? A. B. C. D.

Obtain a CT scan of the maxillary sinus Completion of an antibiotic course and observation Attempt careful visualization and retrieval through the extraction socket Perform a Caldwell-Luc antrostomy

Answer:

C

Rationale: The most appropriate first step in this situation is to attempt visualization and retrieval of the displaced root tip through the extraction socket. If that is unsuccessful subsequent measures should include further radiographic documentation of the root tip position and discussing the operative findings with the patient. Initial localization with periapical or panorex x-rays would be appropriate. If conservative surgical approaches are unsuccessful, then a CaldwellLuc may be appropriate. In general, root tips between 1mm and 3mm and are without infection or pathology can be managed expectantly. A root that is 2mm or greater and exhibits infection or pathology should be removed.

Reference: Wells, DL, Capes, JO, Powers, MP; Complications of Dentoalveolar Surgery in Fonseca, RJ, Oral and Maxillofacial Surgery Vol 1, Anesthesia/Dentoalveolar Surgery/ Office Management, WB Saunders 2000. p432.


72

78. A 23-year-old male is involved in sports related injury and sustains a displacement of his maxillary right central incisor. Which direction of displacement is more likely to lead to pulpal necrosis? A. B. C. D.

Intrusion Extrusion Lateral Palatal

Answer:

A

Rationale: Intrusive forces are more likely to cause direct c ompressive injury to the pulpal vascular supply than forces in any other direction. The risk of pulpal necrosis after intrusion of teeth with a closed apex is 95% and 65% if the apex is open.

Reference: Andreassen JO, Andreassen FM:Essentials of Traumatic Injuries to the Teeth 2 Munksgaard, Copenhagen, 2000, pp 77-112.


nd Edition;

73

79. Which of the following materials used for retrograde fill of an apicoectomy has the lowest success rate? A. B. C. D.

IRM (intermediate restorative material) SuperEBA (ethoxy benzoic acid) Amalgam MTA (Mineral Trioxide Aggregate)

Answer:

C

Rationale: MTA, IRM, and SuperEBA all have success rates greater than that of a retrograde amalgam. Following retrograde preparation with an ultrasonic microtip or use of intraoperative magnification, the success rates of these three materials range from 85-97%. The success rate of traditional retrograde amalgam filling is reported to be much lower, around 68%.

Reference: von Arx T. Failed root canals: the case for apicoectomy (periradicular surgery). Journal of Oral & Maxillofacial Surgery. 63(6):832-7, 2005 Jun.


74

80. Which of the following is a characteristic of cracked tooth syndrome? A. B. C. D.

Percussion sensitivity Pain on release of bite force More likely to occur in a tooth without restorations. The most appropriate treatment is extraction.

Answer:

B

Rationale: Cracked tooth syndrome frequently occurs in teeth that have had 1 or more restorations in the marginal ridge area. The tooth frequently exhibits pain on release of bite force, rather than on percussion. Restoration with onlays, composite resin, or splinting with an orthodontic band is frequently successful. Extraction is necessary only if the tooth root fractures vertically.

Reference: Homewood CI. Cracked tooth syndrome--incidence, clinical findings and treatment. Australian Dental Journal. 43(4):=217-22, 1998 Aug.


75

81. The above axial CT scans are from a patient who developed instantaneous facial swelling during surgical extraction of an erupted tooth utilizing a high-speed dental handpiece. The scans were taken immediately following the procedure. What is the most appropriate management? A. B. C. D.

An antibiotic course and observation Hyperbaric oxygen therapy A cervical drainage procedure A mediastinal drainage procedure

Answer:

A

Rationale: These are axial CT scans of air emphysema. The use of a high-speed dental handpiece for the procedure and the instantaneous swelling are characteristic of this phenomenon. The air was introduced by the handpiece into the cheek, and has progressed along fascial planes into the carotid sheath and then the mediastinum. The treatment of tissue emphysema varies with the severity of the condition. Most cases of subcutaneous emphysema will begin to resolve after 2 to 3 days of supportive treatment, and residual swelling is usually minimal after 7 to 10 days of observation. Treatment is usually conservative, and consists of antibiotic coverage to prevent infection. Oral bacteria may possibly be carried with the aerosol into the soft tissue and represent a potential nidus of infection. Additionally, a course of systemic corticosteroids may promote faster resolution. Surgical decompression of the extensive emphysema should not be routinely used, because it is likely to be ineffective and may even worsen or spread the emphysema. In most cases the patient can be discharged with an explanation of the nature of the tissue emphysema and its course.

Reference: Peterson LJ. Emphysema and dental drill (comment). J Am Dent Assoc 1990; 120:423 Pynn BR, Amato D, Walker DA. Subcutaneous emphysema following dental treatment:report of two cases and review of the literature. J Can Dent Assoc 1192; 58:496-499 Schuman NJ, Edwards BC, Walker W. Subcutaneous emphysema during operative dentistry:report of a case with a thirty-month follow up. J Oral Med 1983; 38:168-169 Woehrlen AE. Subcutaneous emphysema. Anesth Prog 1985; 32:161-163 Salib RJ, Valentine P. Surgical emphysema following dental treatment. The Journal of Laryngoscopy and Otology 1999; 113:756-758 The American Board of Oral and Maxillofacial Surgery

76

82. Fracture of alveolar process during the extraction of a tooth is usually due to: A. B. C. D.

use of excessive amounts of uncontrolled force. presence of adjacent crowded teeth. periapical infection. expansion of surrounding alveolar bone.

Answer:

A

RATIONALE: If the alveolus is fractured, dissect the alveolus off the root, replace the periosteum and alveolus which will act as a vascularized graft. If soft tissue is inadvertently dissected from the alveolus, the segment of bone will likely undergo necrosis. If the maxillary tuberosity is fractured, and the tooth cannot be dissected from the alveolus, replace and splint for 6 – 8 weeks. Later surgically extract the tooth. If the tuberosity is completely avulsed without soft tissue pedicle, then smooth the remaining bony edges and close, checking for oral antral communication.

Reference: Peterson, LJ; Prevention and Management of Complications in Peterson, Ellis, Hupp, Tucker. th Contemporary Oral & Maxillofacial Surgery 4 edition. pp 228-230., Mosby, 2003 USA. rd Peterson LJ:Contemporary Oral and Maxillofacial Surgery, 3 edition Ed. Pg. 261 – 262. Mosby, Missouri


77

83. If the lingual alveolar plate is fractured and mobile during removal of an erupted mandibular third molar, the fractured segment should be: A. B. C. D.

stabilized to avoid damage to the lingual nerve. left in place with minimal manipulation. removed with careful subperiosteal dissection. removed and the lingual nerve explored for evidence of injury.

Answer:

B

Rational: Minimal manipulation of the segment will provide the g reatest chance of maintaining the periosteal attachment, and thus the blood supply to the segment. If soft tissue is inadvertently dissected from the alveolus, the segment of bo ne will likely undergo necrosis. Removal of the segment is generally not advised, dissection in this region would increase the risk of injury to the lingual nerve.

REFERENCE: Berman SA. Basic principles of dentoalveolar surgery. In:=Petersen LJ, Indresano AT, Marciani RD, Roser SM. Principles if Oral and Maxillofacial Surgery. Philadelphia, PA; JB Liincott CO; 1992, pp. 95-96. Peterson, LJ; Prevention and Management of Complications in Peterson, Ellis, Hupp, th Tucker. Contemporary Oral & Maxillofacial Surgery 4 edition. pp 228-230., Mosby, 2003 USA. rd Peterson LJ:Contemporary Oral and Maxillofacial Surgery, 3 edition Ed. Pg. 261 – 262. Mosby, Missouri


78

84. The biological width surrounding natural teeth and freestanding osseointegrated root form implants demonstrate a relatively constant thickness of: A. B. C. D.

1mm. 3 mm. 5 mm. 7 mm.

Answer:

B

Rationale: An appreciation of biologic width is important in best determining implant positioning to allow for an aesthetic result. Numerous studies document the dimensions of biological width for both natural teeth and implants. Biologic width is comprised of the zone of supracrestal connective tissue that measures approximately 1 mm and epithelial structures, including the junctional and sulcular epithelium that measure about 2 mm in height.

Reference: Burglund H, T. and Lindhe, J. “Dimensions of the Peri-Implant Mucosa; Biological Width Revisited”. Journal of Clinical Periodontology, 1996. Vol. 23, pages 971-973. Herman, J. S, Buser, D., Shenk, R.K., Higginbottom, F.L., and Cochran, D. L. “Biological Width Around Titanium Implants:A Physiologically Formed and Stable Dimension Over Time”. Clinical Implants Res., 2000. Vol. 11, pages 1-11.


79

85. Which of the following can cause premature loss of temporary implants used for the purpose of providing orthodontic anchorage? A. B. C. D.

Non-keratinized surrounding mucosa Type of intended tooth movement Mini-plate implant configuration Mini-screw implant configuration

Answer:

A

Rationale: While success rates for mini-implants are high, studies like that of Chang and Tseng demonstrate that implants placed through non-keratinized mucosa have a higher rate of failure. Another factor that may have an adverse affect on success is placement in the posterior mandible. Implant type (mini-screw of mini-plate) does not effect failure rates of rigid orthodontic anchorage.

Reference: Chang, S and Tseng, I, International Journal of Oral and Maxillofacial Implants , 2004, Vol. 19, pages 100-106,


80

86. The most important factor associated with the success of osteotome-mediated sinus floor elevation technique is: A. B. C. D.

the height of the residual alveolar bone. implant design. type of graft material used. method of sinus in-fracture.

Answer:

A

Rationale: The ability to obtain primary implant stability is associated with the height of the residual alveolar ridge, and is the primary factor related to success when implants are placed in conjunction with osteotome mediated sinus floor elevation. Implant design graft material and method of sinus in-fracture have minimal influence on survival; however, factors such as osteoporosis, type of final prosthesis, and operator experience may also impact the success of this technique.

Reference: Toffler, M., “Osteotome Mediated Sinus Floor Elevation: Clinical Report.” International Journal of Oral and Maxillofacial Implants, Vol. 19, No. 2, 2004, pp. 266–273.


81

87. Which of the following has a favorable aesthetic impact on an implant-supported restoration? A. B. C. D.

Thick biotype Thin biotype Restorative table >6 mm apical to the contact point of the adjacent tooth. Positive IL-1 genotype

Answer:

A

Rationale: A thick biotype provides greater stability for the pe ri-implant soft tissues with more predictable healing response following surgery and around restorations. Thin biotypes predispose not only to unpredictable healing but also may allow titanium “show through”. When implant restorative tables are placed more than 5 mm below the contact point of an adjacent tooth, loss of the papilla is common, having an adverse effect on the final aesthetic result. Finally, genetic testing utilizing a swab has identified that positive intraleuken-1 (IL-1) genotype patients have an increased risk of developing periodontitis with enhanced risk of peri-implant complications.

Reference: Buser, Martin and Belser, “Optimizing Aesthetics for Implant Restorations in the Anterior Maxilla: Anatomic and Surgical Considerations”, International Journal of Oral and Maxillofacial Implants. Vol. 19, pages 43-61. Tonel, Magner, and Fletcher. “The Effective Distance from the Contact Point to the Crestal Bone on the Presence or Absence of Interproximal Dental Papilla”, Journal of Periodontology, 1992. Vol. 63, pages 995-96 .


82

88. Which of the following is the best method to determine the completion of facial growth? A. B. C. D.

Use of hand/wrist films. Completion of changes in skeletal height Use of serial lateral cephalograms Attainment of maturity by the Tanner classification

Answer:

C

Rationale: Completion of skeletal height does not correspond to completion of facial growth. A handwrist radiograph is inappropriate for assessing facial growth, because it is not specific enough for each patient. The best method of evaluating the completion of facial growth is by superimposing sequential cephalometric radiographs. Most boys do not complete their facial growth until the late teenage years. A 14- or 15-year-old boy may not have gone through his adolescent growth spurt. It is advisable to wait until an adolescent male has completed growth in height. At that point, a cephalometric radiograph should be taken. Another radiograph should be taken at least 6 months to a year later. If these radiographs are superimposed, and there are no changes in vertical facial height (nasion to menton), this indicates that most of the facial growth has been completed. Achievement of Tanner stage V indicates maturity in development of secondary sexual characteristics, but not skeletal maturity.

Reference: Kokich V:Orthodontic-restorative management of the adolescent patient. In Orthodontics and Dentofacial Orthopedics, eds McNamara JA Jr. Ann Arbor, MI:=Needham Press; 2001. 425-452. Kokich V:Maxillary lateral incisor implants:=planning with the aid of orthodontics. J Oral Maxillofac Surg. 2004 Sep;62(9 Suppl 2):=48-56. Marshall, W, Tanner, J. Variations in the pattern of pubertal changes in girls. Arch Dis Child 1969; 44:=291 Marshall, W, Tanner, JM. Variations in the pattern of pubertal changes in boys. Arch Dis Child 1970; 45:=13. Law, SJ; Use of Orthopedic appliances in Growth Modification in Fonseca, RJ, Oral and Maxillofacial Surgery Vol 6, Cleft/ Craniofacial/ Cosmetic Surgery, WB Saunders 2000. pp 15-17. Bishara, Facial and dental changes in adolescents and their clinical implications. The Angle orthodontist, 200 Vol 70:=6,p 471


83

89. Which of the following is an absolute contraindication for dental implant placement? A. B. C. D.

Oral lichen planus Uncontrolled periodontal disease Insulin dependent diabetes mellitus Cigarette smoking

Answer:

B

Rationale: Contraindications for the use of an implant restoration are in developing patients (particularly in the maxilla, where vertical growth continues after permanent teeth are fully erupted), uncontrolled periodontal disease, aesthetic areas with thin, highly scalloped gingiva, adjacent periapical pathology, and non motivated patients. Relative contraindications where adjacent root flaring precludes placement (correction needed with orthodontics), smokers (increased failure rate especially in type IV bone), connective tissue diseases, and diabetes and autoimmune diseases.

Reference: Salinas TJ, Block MS, Sadan A. Fixed partial denture or single-tooth implant restoration? Statistical considerations for sequencing and treatment. J Oral Maxillofac Surg. 2004 Sep;62(9 Suppl 2):2-16. Lindquist LW, Carlsson GE, Jemt T. Association between marginal bone loss around osseointegrated mandibular implants and smoking habits:A 10 year followup study J Dent Res 1997;76:1667. De Bruyn H, Collaert B. The effect of smoking on early implant failure Clin Oral Implants Res 1994;5:=260 Isidor F, Brondum K, Hansen HJ. Outcome of treatment with implant-retained dental prostheses in patients with Sjögren syndrome Int J 1999;14:736. Balshi TJ, Wolfinger GJ. Dental implants in the diabetic patient:A retrospective study Implant Dent 1999;8:355 Rajnay ZW, Hochstetter RL. Immediate placement of an endosseous root-form implant in an HIV-positive patient:Report of a case J Periodontol 1998;69:=1167


84

91. In 75% of patients, in order for the dental papilla to fill the embrasure space of a single tooth dental implant supported restoration, the maximum distance between the crestal bone and the contact point is: A. B. C. D.

6mm. 5mm. 4mm. 3mm.

Answer:

A

Rationale: The presence or absence of a peri-implant papilla mainly depends on the distance between the alveolar crest and the contact point. In single-tooth gaps, the bone height at adjacent teeth determines the status of the papilla. A clinical study by Dennis Tarnow , et al, demonstrated that a distance of 6mm or more from the alveolar crest to the contact point reduces the probability of intact papillae.

Reference: Tarnow DP, Magner AW, Fletcher P. The effect of the distance from the contact point to the crest of bone on the presence or absence of the interproximal dental papilla. J Periodontology 1992;63:995-996


85

92. The osteotome technique for implant placement: A. B. C. D.

is primarily used in the mandible. is used in Type I bone. compromises vascularity. compresses bone laterally.

Answer:

D

Rationale: In soft maxillary bone, preparation of the implant osteotomy site can be completed using a series of osteotomes rather than burs. Because the maxillary bone is soft, an osteotome can be used to split or widen a narrow ridge to receive an implant. In addition, the osteotome condenses and laterally compresses the soft bone at the osteotomy site, placing a denser, compressed bone immediately adjacent to the implant..

Reference: Fonseca, RJ, Oral and Maxillofacial Surgery Vol 7, Reconstructive and Implant Surgery, WB Saunders, 2000, pp 111-114


86

93. In order to maintain the crestal bone between adjacent dental implants, the implants should be placed at least how far apart? A. B. C. D.

2.0 mm 2.5 mm 3.0 mm 3.5 mm

Answer:

C

Rationale: In sites with adjacent implants, bone resorption of 1 to 2 mm at the proximal aspects of the implant leads to a flattening of the inter-implant bone and consequently a short inter-implant papilla. A distance of at least 3 mm has been recommended between 2 adjacent implants to minimize this bone resorption.

Reference: Tarnow DP, et al. The effect of inter-implant distance on the height of inter-implant bone crest. J Periodontology 2000; 71:=546-549


87

94. When performing immediate placement of an implant into extraction site of a maxillary central incisor, which of the following statements is true? A. B. C. D.

The tooth socket must be completely obliterated by the dental implant. Immediate placement is not recommended if buccal plate integrity is lost. The thick flat gingival biotype has a higher risk of buccal plate resorption. The implant should be placed adjacent to the buccal wall of the extraction site.

Answer:

B

Reference: Hämmerle CHF, et al, Consensus Statements and Recommended Clinical Procedures Regarding the Placement of Implants in Extraction Sockets, Int. J of Oral & Maxillofacial Implants, Vol 19 Supp, pp 26-28


88

95. Soft tissue peri-implantitis occurs most frequently with which of the following implant restorations? A. B. C. D.

Single tooth replacement Implant and tooth supported fixed prosthesis Implanted supported fixed prosthesis Implant supported overdenture

Answer:

D

Rationale: Soft tissue peri-implantitis occurs most commonly in association with implant supported overdentures, with a reported frequency of 11% to 32%. Rates of soft tissue peri-implantitis associated with implant supported fixed prostheses range from 7% to 20%.

Reference: Ardekian, L; Dodson, TB, Complications associated with the placement of dental implants:Oral and Maxillofacial Surg Clin NAm15 (2003) 243-249


89

96. When considering immediate loading of a dental implant, the minimum insertional torque with which the implant must be placed is: A. B. C. D.

2.

10 - 15 N/cm 2. 20 - 25 N/cm 2. 30 - 35 N/cm 2 40 - 45 N/cm .

Answer:

C

Rationale: Studies that use insertion torque values are in general agreement that the values should be at least 30 to 35 Ncm."

Reference: Ganeles, J, Wismeijer, D:Early and Immediately Restored and Loaded Dental Implants for Single-Tooth and Partial-Arch Applications. The International Journal of Oral and Maxillofacial Implants, Volume 19 Supplement, 2004, page 99.


90

97. The minimal bone height required for placement of a transmandibular implant is how many millimeters? A. B. C. D.

3 6 9 12

Answer:

A

Rationale: The cortical screws for the TMI system are available in lengths of 5,8,11, & 14 mm. Protocol is for the cortical screws to extend beyond the bone for a length of 2mm, but not pierce the periosteum. This allows for tenting of the periosteum and thought to lead to subsequent bone growth. A 3mm mandible is the minimum mandibular height to allow 2mm of “tenting” with the 5mm cortical screw. REFERENCE: Powers MP, Bosker H, Pelt AJW, Dunbar N, “ The Transmandibular implant reconstruction system: From progressive bone loss to controlled bone height. JOMS 1994; 52:904-910. Powers MP, Bosker, H The Transmandibular Reconstruction System in Reconstructive and Preprosthetic Surgery, Fonseca and Davis Editors, Second Edition. WB Saunders Co., 1995. pp 565-668.


91

98. When comparing the apically repositioned flap technique and the closed eruption technique for exposure of an unerupted labially positioned maxillary canine lying high in the alveolus, the closed eruption technique results in: A. B. C. D.

less periodontal attachment around the canine. a greater risk of intrusive relapse. improved gingival esthetics. excessive canine clinical crown length.

Answer:

C

Rationale: Both techniques allow for maintenance of the attached gingiva. In the closed eruption technique, a crestal incision is made, and a full-thickness flap is reflected. Bone is carefully removed around the crown and a bracket attached. The flap is closed and the tooth is allowed to erupt down through the crestal incision site as traction is placed on the ligature. The referenced study, comparing the two techniques, shows that although the periodontal attachment level was the same in the two techniques, the labially impacted maxillary anterior teeth uncovered w/ apical flap techniques had more unaesthetic scarring, increased clinical crown length, and greater risk of intrusive relapse. The results of treatment with the closed technique were aesthetically superior and there was less relapse.

Reference: Beck, RJ, Powers, MP; Soft Tissue Considerations in Fonseca, RJ, Oral and Maxillofacial Surgery Vol 7, Reconstruction and Implant Surgery, WB Saunders 2000. p353. Vermette ME: Uncovering labially impacted teeth: Apically positioned flap and closed reduction techniques. Angle Orthodontics 1995; 65: 23-32


92

99. In regard to measured periodontal attachment at the distal of the second mandibular molar following extraction and complete healing of the third mandibular molar, the following is true: A. B. C.

D.

the best results are obtained when guided tissue regeneration techniques are used at the third molar extraction site. the best results are obtained when demineralized bone powder is placed within the third molar extraction site. third molar extraction sites that undergo no special treatment demonstrate periodontal attachment levels similar to those treated with guided tissue regeneration techniques or demineralized bone powder. use of demineralized bone powder within the third molar extraction site more commonly results in formation of a chronic giant cell reaction and periodontal attachment loss.

Answer:

C

Rationale: At the time of third molar extraction, different techniques can be implemented in an attempt to improve the periodontal attachment levels distal to the second molar. A study divided patients undergoing third molar extraction into three different perioperative treatment groups (Guided tissue regeneration (GTR), Demineralized bone powder (DMP), and no special treatment). There were 12 patients in each group. There were no statistical differences between any of the treatment groups in probing depth or attachment level around the second molar. Neither GTR nor DMP techniques showed any advantage over simple healing following third molar extraction

Reference: Dodson TB, Management of mandibular third molar extraction sites to prevent periodontal defects. JOMS. 2004 Oct; 62(10): 1213-24.


93

100.

A 20-year-old presents with a radiolucency associated with an impacted tooth. What is the most common pathologically significant lesion detected on histopathologic examination of the pericoronal tissue? A. B. C. D.

Odontogenic keratocyst Ameloblastoma Odontoma Dentigerous cyst

Answer:

D

Rationale: The cited study reported the histopathologic diagnoses of a large series of pericoronal lesions in adults submitted to an oral and maxillofacial pathology biopsy service. Of the 2646 lesions submitted, 33% showed demonstrable pathology. The most common pathology was dentigerous cyst (28.4%), followed by OKC (3%), odontoma (0.7%), and ameloblastoma (0.5%).

Reference: Curran A, Pathologically significant pericoronal lesions in adults: Histopathologic evaluation. JOMS. 2002 Jun; 60(6): 613-7


94

101.

What stage of root development is optimal for the surgical uprighting of an impacted mandibular second molar? A. B. C. D.

Less than 1/3 root 1/3 2/3 Complete

Answer:

C

Rationale: The procedure is best performed after 2/3 of root development is completed. At this stage the risk of root fracture is minimal. Performing this procedure when less than 2/3 of root development has been completed could result in the second molar floating in its new position. Although the procedure has been performed when root development is complete, the incidence of subsequent pulpal necrosis or calcification is increased.

Reference: Dessner, S; Surgical uprighting of second molars: rationale and technique: Oral and Maxillofacial Surg Clin N Am 14 (2002) 201-212. Costello, BJ, Malik, AKB, Powers, MP, Fonseca, RJ; Complicated Exodontia in Fonseca, RJ, Oral and Maxillofacial Surgery Vol 1, Anesthesia/Dentoalveolar Surgery/ Office Management, WB Saunders 2000. p240.


95

102.

rd

Which statement is correct regarding pericoronitis of a mandibular 3 molar? A. B. C. D.

Initial treatment can be limited to lavage of material alba and debris Pericoronitis occurs only in immunosuppressed patients Antibiotics are mandatory Extraction should be delayed until completion of a course of antibiotic therapy

Answer:

A

Rationale: Antibiotics are a key aspect in localizing an infection and limiting its spread to adjacent tissue organs, areas, and spaces. Pericoronal infections that are localized to the immediate enveloping tissues and give no evidence of spread to adjacent tissue planes require local debridement and definitive treatment consisting of removal of the erupting tooth and/or pericoronal tissues. Antibiotics are not mandatory, and tooth extraction need not to be delayed to complete a course of antibiotics.

Reference: Ness, GM, Peterson, LJ; Impacted Teeth in Peterson's Principles of Oral and Maxillofacial Surgery, Miloro, M. et al., Editors, Second Edition, BC Decker Inc, 2004, pp140-142.


96

103.

Which of the following statements, regarding alveolar osteitis, is true? A. B. C. D.

Generally develops 7-10 days after surgery Represents a localized bone infection Is theorized to be caused by lysis of a fully formed blood clot prior to its replacement by granulation tissue Requires vigorous bone scraping under local anesthesia to stimulate new blood clot formation

Answer:

C

Rationale: Alveolar osteitis is essentially an inflammation of the bony socket from a recently extracted tooth. Treatment consists of debridement of the socket and placement of a suitable obtundent until the area becomes asymptomatic. Usually no local anesthesia is required.

Reference: Ness, GM, Peterson, LJ; Impacted Teeth in Peterson's Principles of Oral and Maxillofacial Surgery, Miloro, M. et al., Editors, Second Edition, BC Decker Inc, 2004, p. 151.


97

104.

rd

Indication for removal of impacted 3 molars include: A. B. C. D.

prevention of mandibular anterior tooth crowding. to allow for postoperative regeneration of bone distal to a 2nd molar with chronic periodontitis. prior to anticipated sagittal split osteotomy. deeply impacted maxillary third molars, prior to anticipated LeFort I osteotomy.

Answer:

C

Rationale: While somewhat controversial, crowding of mandibular incisor teeth app ears to be associated rd with deficient arch length rather than the mere presence of impacted teeth. After 3 molar nd removal the bone height distal to the 2 molar usually remains at the pre-operative level. rd Removal of 3 molars at mandibular advancement osteotomy reduc es the thickness and quality of lingual bone at the proximal aspect of the distal segment where fixation screws are rd usually applied. During a LeFort osteotomy, removal of deeply impacted maxillary 3 molars from the maxillary sinus side may be done safely without compromising the soft tissue vascular pedicle of the maxilla.

Reference: Ness, GM, Peterson, LJ; Impacted Teeth in Peterson's Principles of Oral and Maxillofacial Surgery, Miloro, M. et al., Editors, Second Edition, BC Decker Inc, 2004, pp. 140-153.


98

105.

Which of the following statements is correct regarding the mandibular third molar? A. B. C. D.

The tooth germ is usually visible on a radiograph by the age of 6. By age 11, the tooth is located within the anterior border of the ramus with the occlusal surface facing superiorly. The orientation of the crown within the alveolus may be affected by underdevelopment or overdevelopment of its mesial or distal roots. The tooth’s position from ramus to alveolus is determined strictly by growth of the mandibular body.

Answer:

C

Rationale: rd The mandibular 3 molar, visible radiographically as a tooth germ usually by age 9 within the anterior border of the ramus, progresses with mandibular growth to the body due to resorption of the anterior border of the ramus. The tooth's anterior facing occlusal surface changes orientation to vertical, usually by age 20, during its root development. The failure to progress to final vertical orientation may be attributed to one or more factors including: Over or under development of the mesial and/or distal roots Insufficient arch length to accommodate the normal position of the tooth within the arch

Reference: Ness, GM, Peterson, LJ; Impacted Teeth in Peterson's Principles of Oral and Maxillofacial Surgery, Miloro, M. et al., Editors, Second Edition, BC Decker Inc, 2004, pp. 139-140


99

106.

Which of the following statements regarding adjunctive medications administered to an 18-yearrd old healthy male during removal of 3 molars, is true? A. B. C. D.

Prophylactic antibiotics are recommended to prevent post-operative infection. Local measures are as effective as systemic antibiotics in the reduction of postoperative dry sockets. Perioperative steroids administered to reduce post-operative swelling have no appreciable affect on dry socket incidence Maximum control of swelling requires no additional steroid doses other than the initial perioperative dose

Answer:

B

Rationale: The usage of prophylactic antibiotics involves the issue of risk versus benefits. Without further extenuating conditions, the increase of antibiotic-related complications, e.g. allergy, resistant bacteria, gastrointestinal side effects, and secondary infections, is not outweighed by rd the benefits in an otherwise uncomplicated 3 molar surgery. Perioperative steroids do have a major clinical impact on swelling in the early postoperative period but, for maximum control, additional steroids must be given for 1 or 2 days following surgery. The administration of perioperative steroids may increase the incidence o f alveolar osteitis after third molar surgery, the data are lacking as to the precise degree of increase.

Reference: Ness, GM, Peterson, LJ; Impacted Teeth in Peterson's Principles of Oral and Maxillofacial Surgery, Miloro, M. et al., Editors, Second Edition, BC Decker Inc, 2004, pp 147-149.


100

107.

7 days after third molar extraction, a patient presents with swelling and trismus. The large contrast-enhancing fluid collection on the above scan is best described as residing in which of the following spaces? A. B. C. D.

Submental Masseteric Sublingual Pterygomandibular

Answer:

D

Rationale: This is an axial scan of a pterygomandibular space abscess. The scan reveals a radiolucent, contrast-enhancing collection between the ascending ramus of the mandible and distended medial pterygoid muscle. The lateral pharyngeal space and airway are distorted by mass effect and edema. The borders of the pterygomandibular space are the ascending ramus of the mandible laterally, the medial pterygoid muscle medially, the pterygomasseteric sling inferiorly, and the lateral pterygoid muscle superiorly. The parotid gland and capsule form the posterior border. The pterygomandibular raphe is the anterior border. REFERENCE: Flynn , TR In Topazian , RG, Goldberg, MH, Hupp, JR, editors: Oral and Maxillofacial Infections, ed 4, Philadelphia, 2002, W B Saunders Co., pp 188-213.


101

108.

What stage of root development is optimal for the transplantation of a developing mandibular third molar to a first molar extraction site? A. B. C. D.

Less than 1/2 Between 1/2 and 2/3 Between 2/3 and complete Complete

Answer:

B

Rationale: The donor third molar roots should be no less than half and preferably about two thirds developed.

Reference: Silva, RG, Pogrel, MA; Tooth Reimplantation and Transplantation in Fonseca, RJ, Oral and Maxillofacial Surgery Vol 1, Anesthesia/Dentoalveolar Surgery/ Office Management, WB Saunders 2000. pp 299-301. Kaban, LB, Dentoalveolar Surgery in Kaban Pediatric Oral and Maxillofacial Surgery, WB Saunders, 1990, p109.


102

109.

On the above scan, what is the location of the third third molar inadvertently displaced displaced during an attempted extraction? A. B. C. D.

Superficial temporal space Maxillary sinus Pterygomaxillary fissure Infratemporal space

Answer:

D

Rationale: The tooth clearly is not in the maxillary sinus. Additionally is not in the pterygomaxillary fissure between the pterygoid plate and posterior maxilla. The level of the scan is below below the superficial temporal space, the inferior inferior boundary of which is the the zygomatic arch. The tooth resides in the infratemporal space. The infratemporal space is the portion of the deep temporal space that lies inferior to the infratemporal crest crest of the sphenoid bone. The inferior border is the superior surface of the lateral pterygoid muscle. The anterior border of the deep temporal temporal space is composed of the posterior wall of the maxillary sinus, the pterygomaxillary fissure, and the posterior surface of the orbit, including the inferior orbital fissure.

Reference: Flynn, TR In Topazian, RG, Goldberg, MH, Hupp, JR, editors: Oral and Maxillofacial Infections, ed 4, Philadelphia, 2002, W B Saunders Co., pp 200-203.


103

110.

The diagnosis of mitral valve prolapse is associated with which of the following? A. B. C. D.

Early systolic murmur Von Willebrand’s syndrome Murmur accentuated by respiration Patent ductus arteriosus (PDA)

Answer:

B

Rationale: Mitral valve prolapse is a common condition affecting 2%-5% of the population. It likely is inherited as an autosomal dominant trait, trait, and is more common in women. The murmur associated with mitral valve prolapse occurs late in systole and is not affected by respiration. MVP is associated with ventricular premature beats, paroxysmal atrial tachycardia, atrial fibrillation, Von Willebrand's syndrome, polycystic kidney disease, atrial secundum defects and Marfan's syndrome.

Reference: th LeBlond R, DeGowin R, Brown D:DeGowin's Diagnostic Examination 8 ed., McGraw-Hill, New York, 2004, pp.428-429. Sdrales L, Miller R:Anesthesia Review., Churchill Livingstone, Philadelphia, 2001, pp.268-269.


104

111.

Intravenous conscious sedation is being administered administered to a 62-year-old male with a history of exertional angina. Local anesthetic without a vasoconstrictor has been infiltrated and extraction of tooth #12 has been accomplished. Abruptly, the patient’s blood pressure pressure rises 60% above baseline. Conservative measures fail to reduce the blood pressure and pharmacologic intervention is now required. Which antihypertensive agent is contraindicated in this setting? A. B. C. D.

Esmolol Clonidine Hydralazine Labetalol

Answer:

C

Rationale: Sustained elevated blood pressure can lead to left ventricular failure, pulmonary edema, myocardial ischemia, and cardiac dysrhythmias. Antihypertensive agents must be chosen carefully when a patient with a history of ischemic heart disease is being treated. Labetalol is a selective Alpha, and nonselective Beta-blocker. Reflex tachycardia is not seen after administration and cardiac output is not changed. Pulmonary artery and wedge pressures decrease. Esmolol is a rapid rapid acting cardioselective beta blocker which does not increase cardiac output or cardiac cardiac oxygen consumption. Oral clonidine is a centrally acting alpha agonist with a wide margin of safety. Hydralazine is a parenteral antihypertensive that acts as a direct vasodilator., and may result in unopposed beta stimulation with significant reflex increases in cardiac output. Hydralazine is contraindicated when a patient has a history of ischemic heart disease.

Reference: Crawford M:Current Diagnosis & Treatment in Cardiology., Lange Medical Books/McGrawHill, New York, 2003, pp.176-178. Ogle O, ed:Oral and Maxillofacial Surgery Clinics of North America., W.B. Saunders, Philadelphia, 1998, Vol 10, No.3, pp.349-361.


105

112.

A thin appearing 52-year-old male with a long history of alcohol abuse is having multiple dental extractions under local anesthesia when he suddenly becomes disoriented and confused. An ECG reveals a polymorphic ventricular tachycardia. His vital signs are as follows: BP 85/55, HR 165, RR 22. Which is the most appropriate drug to administer? A. B. C. D.

Epinephrine Amiodarone Lidocaine Magnesium

Answer:

D

Rationale: Chronic alcoholism and malnutrition is frequently associated with hypomagnesemia which can provoke a polymorphic ventricular tachycardia, torsades de pointe, with a prolonged QT interval. The immediate treatment is to administer magnesium. Epinephrine may increase myocardial irritability and worsen the tachycarida. Amiodarone prolongs the QT interval which can cause a worsening of the torsades. Lidocaine may be given but is not as efficacious as magnesium for this type of arrhythmia. If available, overdrive pacing is an acceptable alternative to magnesium.

Reference: Cummins:Case 3. ACLS Provider Manual:75-95, 2001


106

113.

A 20-year-old female presents for routine third molar surgery. She appears emaciated, has indicated that she has an “eating disorder” and you confirm that she has anorexia nervosa. Which one of the following pre-operative tests is most indicated prior to surgery? A. B. C. D.

AST, GGT, ALT, and alkaline phosphotase 24 hour urine for metanephrines serum electrolytes Coagulation tests (PT, PTT, fibrin degradation products)

Answer:

C

Rationale: Dysfunction is found in most organ systems in the severely malnourished patient, but the most dangerous are fluid/electrolyte disorders. Amongst the answers given, a determination of electrolyte status would be the most appropriate in this situation. Other pertinent pre-op tests would include an electrocardiogram and complete blood count. Metabolic alkalosis, hypocalemia, and hypokalemia may manifest with prolongation of the QT interval. Sudden death in these individuals is often precipitated by ventricular arrhythmias. AST, GGT, ALT and alkaline phosphatase are blood screening tests for hepatic function. Although anorexia may affect the hepatobiliary system, cardiac function associated with anorexia would have the greatest potential impact in safely managing this patient. A 24 hour urine measuring the levels of metanephrines would be an appropriate study in the differential diagnostic work up for an adrenal neoplasm (such as a pheochromocytoma). This study will not yield any data that would assist in the diagnosis or management of anorexia nervosa. Although Prothrombin time (PT) and Partial Thromboplastin Time may be prolonged secondary to liver disease, these are not usually associated with anorexia. Fibrin degradation products are associated with disseminated intravascular coagulopathy (DIC), not with anorexia.

Reference: th The Merck Manual, 17 Ed., Merck and Co., 1999, pp.1595-6. 2002 Ferri's Clinical Advisor, Fred Ferri, Mosby 2002 Edition, pp. 66-7.


107

114.

During cardiac exercise stress testing, ECG monitoring during or after exercise would look for signs of ischemia based on: A. B. C. D.

excessively tall QRS complexes. prolonged P-R intervals. biphasic P-waves. ST depression.

Answer:

D

Rationale: Patients with stress-induced symptoms of ischemia usually provide the best assessment of risk for adverse events from CAD. Ischemic tendencies would be evidenced by the presence of ST depression or inverted T waves. The addition of cardiac imaging increases the sensitivity of the stress test, especially when resting ECG abnormalities exist or conditions are present that may cause abnormal stress-induced ECG changes not secondary to ischemia. Excessively tall QRS complexes may indicate ventricular hypertrophy. Prolonged P-R intervals indicate conduction delay at a location between the atria and the ventricles (such as at the A-V node.) Biphasic P waves are indicative of atrial hypertrophy.

Reference: OMS Knowledge Update; Vol. I, Part II, 1995, p PEV21. Peterson LJ, Indresano AT, Marciani RD, Roser SM, Principles of Oral and Maxillofacial Surgery; 1992, Chapter 2, p 20.


108

115.

An obese 60-year-old male presents for extraction of tooth #32. His past medical history is significant for angina, syncopal episodes and congestive heart failure. A crescendo-decrescendo systolic murmur is noted upon auscultation of the precordium. The most likely diagnosis is: A. B. C. D.

aortic regurgitation. mitral stenosis. aortic stenosis. mitral regurgitation.

Answer:

C

Rationale: Aortic stenosis is the most common congenital cardiac abnormality. Patients typically present with angina, syncope and congestive heart failure. The classic murmur of aortic stenosis is a harsh systolic ejection murmur. The only effective treatment is valve replacement. Aortic regurgitation is associated with a high pitched diastolic decrescendo murmur. Mitral stenosis auscultation yields a diastolic rumble, loud S1, and an opening snap. Mitral regurgitation creates a holosystolic murmur with radiation to the axilla.

Reference: Crawford M:Current Diagnosis & Treatment in Cardiology., Lange Medical Books/McGrawHill, New York, 2003, pp.108-117. Andreoli T:Cecil Essentials of Medicine., W.B. Saunders, Philadelphia, 2004, pp.78-80.


109

116.

Tricuspid valve insufficiency initially produces: A. B. C. D.

atrial fibrillation. left Ventricular dilitation. volume overload of right atrium/ventricle. ventricular Tachycardia.

Answer:

C

Rationale: Insufficiency of the tricuspid valve initially produces a volume overload to the right atrium and ventricle, which dilate as a compensatory mechanism. This gives rise to elevated central venous pressures which cause right sided “congestive failure.” If the tricuspid regurgitation is massive, under-filling of the left heart can result.(this last sentence need a little work)

Reference: Luce J, Pierson D (Eds.):Critical Care Medicine, 1988,WB Saunders, p. 47.


110

117.

Idiopathic Hypertrophic Subaortic Stenosis (IHSS): A. B. C. D.

obstructs right ventricular outflow. diminishes diastolic valvular function. affects left ventricular outflow. hypertrophies the tricuspid valve.

Answer:

C

Rationale: IHSS is usually an inherited autosomal dominant characteristic, and can be associated with long term hypertension. Depending on the area of hypertrophy, the systolic left ventricular outflow can be significantly obstructed during systole. Fatal dysrhythmias and sudden death may result even in healthy teenagers with undiagnosed hypertrophy.

Reference: Peterson's Principles of Oral and Maxillofacial Surgery, Second Edition, Vol I pg 69


111

118.

Which of the following statements concerning intravascular replacement is true? A. B. C. D.

0.9% saline is isosmolar to lactated Ringer’s solution Renal resorption of potassium makes intravenous supplementation unnecessary Excessive lactated Ringer’s solution administration can cause hypermagnesemia One liter of 5% dextrose in water yields 200 kilocalories

Answer:

D

Rationale: One liter of 5% dextrose in water yields 50 g of dextrose; with available calories:4 kcal/gm, or 200 kcal. O.9% (normal) saline has an osmolality of 308; while lactated Ringer's solution is 273. Obligate renal potassium losses are about 40 mEq/day, and requires replacement (either from oral intake or by a parenteral supplement.) Ringer's lactate has no magnesium hence no possibility of hypermagnesemia.

Reference: th Washington University Manual of Medical Therapeutics (30 ed.), pp43-45


112

119.

Woff-Parkinson-White (WPW) Syndrome: A. B. C. D.

is treated with verapamil IV. requires extra-nodal conduction. is characterized by severe bradycardia. is unresponsive to radiofrequency ablation.

Answer:

B

Rationale: During normal embryonic cardiogenesis, strands of electroconductive tissue form connections between the atria and ventricles outside of the normal conduction pathway. These strands normally become non-functional shortly after birth. In WPW, persisant connections via extranodal pathways bypass part of all of the normal conduction system and function in a re-entry capacity. In WPW the accessory pathway is called the Kent Bundle and connects the atria directly to the ventricles and is a cause of atrial fibrillation. This can result in a ventricular rate of 250-300 beats/min. Treatment of WPW, especially if atrial fibrillation is present, with IV verapamil may decrease the accessory pathway refractory period, increasing the ventricular rate and potentiating ventricular fibrillation. Radiofrequency ablation has become one of the procedures of choice in ablating the accessory conductive pathways in WPW syndrome.

Reference: ACLS Quick Review Study Guide, Second Ed. Barbara Aehlert, RN pg 180 Mosby.


113

120.

Which of the following concerning acute chest pain is true? A. B. C. D.

ST depression and chest pain with positive cardiac troponins are an indication for thrombolytic therapy Q-wave MI’s contraindicate percutaneous coronary angioplasty Unstable angina is an indication for antiplatelet medication Heparin may not be used with fibrinolytic therapy

Answer:

C

Rationale: Unstable angina is a pre-infarctive condition, in which the developing thrombus is platelet rich and where antiplatelet drugs are indicated. ST depression with lack of Q waves and positive cardiac troponin indicate an early or intermittent infarction (termed a non-Q-wave myocardial infarction.) The thrombus at this stage is a mixture of a fibrin clot and platelets; and treatment at this time with a thrombolytic may liberate clot-bound thrombin, enlarging or embolizing the clot and may paradoxically worsen coronary occlusion. Q wave MIs indicate total thrombotic occlusion and are an indication for prompt coronary angioplasty. Heparin is commonly used with both fibrin specific thrombolytics and with angioplasty procedures.

Reference: ACLS Provider Manual (2001), pp123-127


114

121.

Which of the following is most likely to be associated with untreated mitral stenosis? A. B. C. D.

Increased pulse pressure Right atrial hypertrophy Pulmonary hypertension Left ventricular hypertrophy

Answer:

C

Rationale: Mitral stenosis is associated with diminished pulse pressure as there may be impaired left ventricular filling. A triad of symptoms associated with MS includes left atrial hypertrophy, pulmonary hypertension and right ventricular hypertrophy due to stenosis of the mitral valve. This condition requires the cardiac structures upstream from the mitral valve to overcome increased resistance across a stenotic mitral valve resulting in hypertrophic c hanges in those areas. Note: pulmonary hypertension is the result of smooth muscle hypertrophy involving the pulmonary arteriolar bed.

Reference: McCabe, Roser: Evaluation and management of the cardiac patient for surgery. Oral Max Surg Clin of N Amer 10:3, 1998. Ramadan, et al: Preoperative evaluation of cardiac risk. Adv Surg 28: 1995


115

122.

A 40-year-old male comes to your office as a new patient upon referral from his family physician for recurrent pericoronitis of a lower third molar. He is currently asymptomatic, and desires a deep sedation for third molar removal. His physical examination reveals an early systolic click and a 2/6 murmur in the aortic area. In the referral letter, his physician notes the following test results: ECG is normal; echocardiogram shows a bicuspid aortic valve without significant flow obstruction. His ventricle size and function are normal. What intervention would be warranted prior to proceeding with an office anesthetic and surgery for this patient? A. B. C. D.

Antibiotic endocarditis prophylaxis Aortic valve replacement Balloon valvuloplasty No intervention

Answer:

A

Rationale: All patients with bicuspid aortic valves --- even those with no significant stenosis or regurgitation --- should be given antibiotic prophylaxis for bacterial endocarditis for surgeries involving the aerodigestive tract. As much as 2% of the population has congenitally bicuspid aortic valves. A bicuspid aortic valve may present as an incidental finding on physical examination or echocardiography done for other reasons. On physical examination, the cardinal sign of a bicuspid aortic valve is an early systolic ejection click. If no significant hemodynamic abnormality is present, either no mu rmur or a soft ejection murmur may be heard; a very mild murmur of aortic regurgitation (AR) is not uncommon, even with hemodynamically insignificant bicuspid aortic valves. Aortic stenosis (AS) or AR from any other cause will produce similar findings. Both the presence of a bicuspid aortic valve and its hemodynamic significance can be determined by echocardiography. Serial studies are useful in following the progression of the lesion.. Patients with AR from a bicuspid valve who are asymptomatic and have normal systolic function a re followed with echocardiograms and physical examinations at regular intervals. If they begin to show decreasing systolic function, symptoms of heart failure, or progressive dilation of the left ventricle, surgical replacement of the aortic valve is indicated.

Reference: th Harrison's Principles of Internal Medicine 14 ed, p. 1320


116

123.

Which of the following may be observed in pulmonary sarcoidosis? A. B. C. D.

Distortion or obstruction of the airway Obstructive lung disease Pneumothorax in early stages Sparing of parenchyma

Answer:

A

Rationale: Sarcoidosis is a multisystem granulomatous disease. Respiratory manifestations include laryngeal granulomas or nodules as well as intrathoracic nodes that may compress or distort the airway. Involvement of the recurrent laryngeal nerve can cause unilateral vocal cord paralysis. Obstruction of the lower airways can result in atelectasis, but local obstruction is not the same as obstructive lung diseases. Sarcoidosis is a restrictive lung disease, with the majority of pulmonary damage occurring in the parenchyma. Patients may be prescribed steroids and perioperative care must ensure appropriate steroid coverage. Pulmonary fibrosis seen in advanced stages of the disease and may result in a pneumothorax. Patients generally take rapid shallow breaths to compensate for the physiologic changes. Hypoxemia is common at rest in severe disease.

Reference: Kinney MAO, Harrison BA, Ruyter MLD: Sarcoidosis in Complications in Anesthesia Eds Altee JL. WB Saunders 1999


117

124.

Which laboratory study is the most informative in the diagnosis of asthma? A. B. C. D.

Plane chest radiography Spirometry Arterial blood gas determination Stethoscopy

Answer:

B

Rationale: Asthma diagnosis rests upon the measurement of peak expiratory flow rates (spirometry) before and after administration of an inhaled beta adrenergic agonist; the reversibility of lowered expiratory flows being diagnostic for this disorder. Alterations in plane chest radiographs, arterial blood gases, and in auscultation of the chest by stethoscope may occur with asthma, but changes in these are not specific for the diagnosis of asthma.

Reference: th Little JW, Falace DA et al: Dental Management of the Medically Compromised Patient 6 th ed. . St. Louis, Mosby, 2002 p. 132. Harrison's Principles of Internal Medicine 14 ed. New York, McGraw-Hill, 1997 p. 1423


118

125.

A 28-year-old patient suffers a prolonged laryngospasm in your office. Upon breaking the spasm through the use of positive pressure oxygen and succinylcholine, the patient is still somewhat somnolent and difficult to arouse. His respiratory rate is 16/min and there are crackles heard throughout his lung fields, especially nea r the bases. At this point the patient will likely require: A. B. C. D.

bronchial alkalinization. positive end expiratory ventilation. pleurocentesis. antibiotics.

Answer:

B

Rationale: Patients who have had a laryngospasm may be susceptible to secondary pulmonary edema. This can be the result of negative alveolar pressure of an expanding diaphragm against a closed glottis, or due to barotrauma from positive pressure ventilation. Pulmonary trauma arising from laryngospasm may become clinically evident hours after the spasm. In this case, signs arising immediately after the treated laryngospasm may indicate imminent pulmon ary failure which may require endotracheal intubation and airway support using positive end expiratory pressure, and possibly diuretics. While this patient may have had an aspiration, the management of this complication would not be alkalinization of the airways. It is unlikely that the acute onset of dyspnea in this case was due to pleural effusion or pneumonia

Reference: Brandom BW. Pulmonary Edema After Airway Obstruction. International Anesthesiology Clinics 35(3):75-84, 1997. Halow KD, Ford EG. Pulmonary Edema following Post-operative Laryngospasm:A Case Report and Review of the Literature. American Surgeon 59(7):=443447, 1993.


119

126.

Which is a characteristic feature of pulmonary emphysema? A. B. C. D.

Increased hematocrit Cor pulmonale Decreased functional residual capacity PaCO2 is normal to slightly decreased

Answer:

D

Rationale: Chronic obstructive lung disease encompasses chronic obstructive bronchitis and emphysema. With both disorders, FEV/ FVC is decreased; but residual volume, functional residual capacity and tidal volume are generally increased. Chronic obstructive bronchitis is referred to as “blue bloater”. The disease is characterized by obstruction of small airways secondary to mucus and inflammation. Patients with chronic bronchitis have significant decreases in PaO2 (< 65 mmHg is typical.) Compensatory consequences include erythrocytosis. PaCO2 is also chronically elevated. This results in pulmonary hypertension and cor pulmonale. Physiologic changes found with emphysema include destruction of lung parenchyma, enlargement of airway spaces, loss of lung elasticity and closure of small airways. Rapid, shallow respirations generally result in a PaCO2 which is normal to slightly decreased and a PaO 2 > 65 mmHg. This disease is categorized as “pink puffer” and is generally not associated with cor pulmonale.

Reference: nd Stoelting RK & Dierdorff SF: Handbook for Anesthesia and Co-Existing Disease. 2 edition Churchill Livingston 2002


120

127.

Which of the following statements concerning pulmonary thromboembolism is true? A. B. C. D.

ELISA test for d-dimer yields the quickest diagnostic results Helical CT is highly specific indicator for subsegmental emboli Fluid replacement is indicated for decreased left ventricular output Serial deep venous ultrasonography is indicated if other tests yield equivocal results

Answer:

D

Rationale: The diagnosis of pulmonary thromboembolism can be difficult, and the results of clinical, laboratory, and radiologic exams can be equivocal. Testing is generally based upon risk stratification (according to clinical presentation, medical history, surgical procedures, and other risk factors both for developing PE and for risks of this disorder.) The most common suspected site of origin for pulmonary thrombi are from deep leg veins; so in the case of suspected but unconfirmed PE, repeat serial leg vein ultrasound is indicated. ELISA tests vary in sensitivity the d-dimer breakdown products from thrombi; with the results generally not immediately available. Venous contrast helical CT is being advocated as a screening tool for PE, but this modality has not proven to be highly sensitive or specific for (small) subsegmental PE's, which are notoriously difficult to diagnose. Decreased in left ventricular output are an ominous sign in PE, caused by decreased left atrial filling. Fluid bolus therapy in these patients, who already are in right heart failure, is contraindicated.

Reference: Kearon C: Diagnosis of pulmonary embolism. J. Can. Med Assoc, 168:2, Jan 2003 Goldhaber S: Pulmonary thromboembolism. In: Fauci et al (eds;) Harrison's Principles of th Internal Medicine 14 ed. p. 1468


121

128.

Montelukast has its primary mechanism in reducing inflammation associated with asthma through: A. B. C. D.

inhibition of prostaglandins. antagonism of leukotrienes. direct beta-2 stimulation. blocking production of arachidonic acid.

Answer:

B

Rationale: Leukotrienes are potent biochemical mediators that are released from mast cells, eosinophils, and basophils. Leukotrienes work to contract airway smooth muscle, increase vascular permeability and mucus secretions, and attract and activate inflammatory cells in the airways of patients with asthma. They are produced by the oxidation of arachidonic acid through the enzyme lipoxygenase. The action of leukotrienes can be blocked through either of two specific mechanisms: 1) inhibition of leukotriene production and, 2) antagonism of leukotriene binding to cellular receptors. The FDA has approved three products thus far. Zafirlukast and montelukast are both selective and competitive leukotriene receptor antagonists of leukotriene D and E. These are components of slow-reacting substance of anaphylaxis. Zileuton, a specific inhibitor of 5-lipooxygenase, inhibits leukotriene formation, R especially LTB1, LTC1, LTD1, LTE1. As a leukotriene antagonist, Singulair (montelukast) has no effect on lipoxygenase or arachidonic acid function. Arachidonic acid is produced by membrane phospholipids through the enzyme phospholipase A2 which is blocked by corticosteroids. Cyclooxygenase inhibitors (i.e. NSAIDs, COX inhibitors) block the production of prostaglandins. Beta-2 stimulation results in bronchodilation and is the main mechanism of medications such as albuterol and not the leukotriene inhibitors.

Reference: Kastrup EK, et al. (eds) Respiratory drugs. In Drug Facts and Comparisons, 1998. St. Louis, Facts and Comparisons. Pp 1133-1140. Aharony D. Pharmacology of leukotriene receptor antagonists. Am J Respir Crit Care Med 1998;157:S214-9.


122

129.

Which of the following decreases pulmonary diffusion capacity? A. B. C. D.

Acute respiratory distress syndrome Diaphragmatic paralysis Chylothorax Pleural effusion

Answer:

A

Rationale: The diffusion capacity of the lungs for any gas is dependent upon the diffusion coefficient (for the gas in question), the surface area and thickness of the alveolar-capillary membrane, and the partial pressure gradient across the barrier. Changes in any of these variables will affect the diffusing capacity. The alveolar –capillary membrane is made up of various layers. These layers traveling from the alveolus toward the ca pillary are: surfactant layer, alveolar epithelium, interstitial space, pulmonary capillary endothelium, plasma, and red blood cell. On average, this barrier is about 0.5 µm in thickness. Alveolar edema or exudates such as in acute respiratory distress syndrome increases the thickness of the blood-gas barrier in the lung, which increases the time necessary for equilibration of CO2 and O 2 across the bloodgas barrier. Diaphragmatic paralysis will inhibit air exchange but not the ability to equilibrate gaseous exchange across the alveolar/capillary surface. A pleural effusion and chylothorax are is present in the pleural space and therefore will not directly affect the diffusion of g ases in the alveoli of the lung.

Reference: Vander AJ, Sherman JH, Luciano DS: Respiration In Human Physiology: The Mechanisms of th Body Function, , 4 edition, 1985. Pocock, G. & Richards, C.D. – Human Physiology: the st Basis of Medicine, Oxford Core Texts, 1 Edition, 1999


123

130.

Which of the following can be used to classify an airway in the Fujita system? A. B. C. D.

Epworth Sleep Scale Polysomnography Bed partner interview Nasopharyngoscopy

Answer:

D

Rationale: Nasopharyngoscopy , especially supine and using Mueller's Maneuver (holding the nose and mouth closed against forced inspiration) is the most useful to diagnose the level of airway obstruction in the sleep apnea patient. A Fujita Type II airway obstruction occurs at both the retropalatal (oropharyngeal) and retrolingual (hypopharyngeal) areas; while a Type I is retropalatal and Type III is retrolingual. Polysomnography establishes the diagnosis of obstructive sleep apnea but not the location of obstruction. The Epworth Sleep Scale is a subjective evaluation of daytime hypersomnolence and is useful in the referral of patients for further sleep disorder work up. The interview of a bed partner, especially as to sonorous breathing, loud snoring, or observed obstructive apneas is highly sensitive for the presence of obstructive sleep apnea and should prompt the practitioner to further sleep disorder work up including polysomnography.

Reference: Bond T: Evaluation and diagnosis of sleep-disordered breathing. OMS Clinics N America14:3, 293-296 Aug 2002


124

131.

Which of the drugs listed below is appropriate for use in the epileptic patient with asthma? A. B. C. D.

Piroxicam Methohexital Morphine Ketamine

Answer:

D

Rationale: The sources of asthmatic airway processes are rapid release of chemical mediators, abnormalities of airway neuroregulation, or an intrinsic defect of airway smooth muscle. Ten percent of patients with asthma can experience bronchial constriction and rhinorrhea in response to aspirin or NSAIDs such as prioxicam. The mechanism is via blockade of prostaglandin synthesis, causing leukotriene build up. Methohexital may be epileptogenic (unlike other barbiturates); and histamine release by methohexital or morphine may also precipitate an asthma attack. Ketamine acts as a bronchidilator and does not possess epileptogenic properties.

Reference: th Little J, Falace D: Dental Management of the Medically Compromised Patient 6 ed., th Mosby, St. Louis 2002, P 136. Malamed S: Sedation: A Guide to Patient Management 4 ed, Mosby, St. Louis, 2003, pp 560-561. Ruggiero S: Evaluation, Treatment, and Management of the Asthmatic Patient, Oral and Maxillofacial Surgery Clinics of North America, WB Saunders, Philadelphia, 10:3 Aug 1998, pp339-343


125

132.

An early diagnostic test used to test infants suspected of having cystic fibrosis is: A. B. C. D.

urine sodium. sweat chloride. fecal aluminum. sputum alcohol level.

Answer:

B

Rationale: Cystic fibrosis is an autosomal recessive inherited disease of the exo crine glands, primarily affecting the GI and respiratory systems, and usually characterized by COPD, exocrine pancreatic insufficiency, and abnormally high sweat electrolytes (particularly chloride > 60 mEq/L). In addition to thickened sputum and pancreatic enzyme dysfunction, males often have azospermia secondary to obstruction of the vas deferens by thickened secretions.

Reference: Facts About Cystic Fibrosis, Cystic Fibrosis Foundation, Bethesda, MD, November 16, 2001. Farrell, P.M., et al. Early diagnosis of cystic fibrosis through neonatal screening prevents severe malnutrition and improves long-term growth. Pediatrics, volume 107 , number 1, January 2001, pages 1-13.


126

133.

Which antibiotic has the greatest potential for adverse interaction with theophylline? A. B. C. D.

Penicillin Clindamycin Cephalexin Ciprofloxacin

Answer:

D

Rationale: Theophylline, a thioxanthine, acts centrally as an indirect adrenergic, causing dilation of bronchial smooth muscle and is used in the management of refractory asthma. Toxicity is manifested as hyperadrenergia including tachycardia, hypertension, and hyperreflexia. Erythromycin reversibly inhibits hepatic degradation of theophylline and can lead to toxic serum levels of the bronchodilator. The same is true with concomitant use of theophylline with cimetidine, ciprofloxacin, and allopurinol. Clindamycin, cephalexin, and penicillin do not diminish theophylline metabolism.

Reference: Abubaker AO, Benson KJ: Oral and Maxillofacial Surgery Secrets, Philadelphia, Hanley & Belfus, 2001 P. 122


127

134.

In a healthy individual, the major factor in regulation of alveolar ventilation is arterial: A. B. C. D.

PaO2 PaCO2 pH HCO3

Answer:

B

Rationale: A number of factors play a role in controlling alveolar ventilation. The central areas of inspiratory and expiratory control lie in the medulla, and primarily respond to increases in hydrogen ion concentration in the cerebrospinal fluid. Although hydrogen ion concentration is the most important stimulus to the chemosensitive centers in the medulla, these ions cross from blood through the blood-brain barrier to ce rebrospinal fluid with difficulty. In contrast, CO2 readily crosses the blood-brain barrier to react with water to form carbonic acid in the CSF, which dissociates to provide the required hydrogen ion necessary for stimulation. Peripheral chemoreceptors transmit signals via cranial nerves ten (to the aortic bodies) and nine (to the carotid bodies) to the inspiratory area of the medulla and pons. These signals help control breathing frequency and lung inflation. The peripheral receptors respond to drops in arterial oxygen pressure. Generally speaking, carbon dioxide pressure plays a much greater influence on ventilation than oxygen pressure. To exemplify the role that the PaCO2 plays in controlling alveolar ventilation, a 50% increase in arterial PaCO2 produces a tenfold increase in alveolar ventilation, while a 40mmHg decrease in arterial PaO yields only a 1.5 fold increase in alveolar ventilation. The high blood flow through the richly vascularized peripheral chemoreceptors allows the needs of the receptors to be almost entirely met by dissolved oxygen, and excess oxygen bound as oxyhemoglobin is not used by the receptors. As a result, the PaO2 determines the level of peripheral receptor stimulation rather than the arterial oxygen saturation (SaO2).

Reference: rd Stoelting R: Pharmacology and Physiology in Anesthetic Practice 3 ed., Lippincott, Williams, and Wilkins, New York, 2001, pp 726-728. Morgan G, Maged S, Clinical nd Anesthesiology 2 ed., Lange Medical Books, New York, 1996, pp436-437.


128

135.

A 24-year-old male motorcyclist is involved in a head on collision with a stationary vehicle. His GCS on arrival is 8. As you are completing the secondary survey his blood pressure acutely rises to 220/140. A ventriculostomy is placed and indicates his intracranial pressure is 40mmhg. What is his cerebral perfusion pressure? A. B. C. D.

20mmHg 70mmHg 130mmHg 170mmHg

Answer:

C

Rationale: Cerebral perfusion pressure is calculated by the following formulae: Mean arterial pressure: diastolic blood BP + 1/3 (systolic BP – diastolic BP) 140 + 1/3 (220-140) 167 Cerebral perfusion pressure (CPP): Mean arterial pressure-Intracranial pressure (ICP) 167 – 40 127 (about 130) Cerebral blood flow is constant when CPP is maintained between 50-150mmHg. To maintain cerebral blood flow, the MAP should be between 60-160mmHg and the ICP between 515mmHg. As the ICP begins to rise, cerebral autoregulation occurs increasing cerebral vascular resistance causing cerebral hypertension in an attempt to maintain cerebral blood flow.

Reference: Cushing H. The blood pressure reaction of acute cerebral compression, illustrated by cases of intracranial hemorrhage. Am J Med Sci:125, 1017-1044, 1903


129

136.

A 70 kg, 35-year-old female is undergoing removal of a submandibular gland for sialolithiais under intubation general anesthesia. She was induced with 100mg propofol, and was given vecuronium as the paralytic agent. Isoflurane was used for maintenance of general anaesthesia. The case took approximately 60 minutes. At the end of the procedure she continued to have significant neuromuscular blockade. She was awake, able to open her eyes able and follow commands with difficulty. Her neurologic exam was nonfocal. She exhibits the following: respiratory rate 16/ min, tidal volume 100cc. end tidal CO2 55mmHg. What is the first diagnostic test that would be appropriate? A. B. C. D.

Edrophonium (Tensilon) Test Head CT Electromyography Pyridostigmine Test

Answer:

A

Rationale: Myasthenia gravis is an acquired autoimmune disorder affecting transmission at neuromuscular junction. It is an autosomal dominant condition. 80-90% of patients will have auto antibodies to the acetylcholine receptors of the post synaptic membrane. Patients exhibit prolonged neuromuscular blockade to non-depolarizing muscle relaxants; but usually show some resistance to the muscle paralysis of succinylcholine. When MG is suspected the first test that may be performed is the Tensilon test using edrophonium 2mg IV wait 30 seconds for effect, assess for improvement in muscle strength that lasts for 5minutes. Repeated doses of 8mg may be given. If this test is positive supportive care is required until the neuromuscular blockade improves. In a myesthenic crisis plasmapheresis may be indicated for temporary relief, but not as first line measure. Head CT would not be the first line diagnostic test in an awake patient who has a nonfocal neurologic examination. Electromyography and muscle biopsy can be used as definite test for MG. Pyridostigmine is used for treatment of MG, and not usually for diagnosis due to its slower onset and longer duration of action.

Reference: Sanders DB. Myasthenia Gravis and Myasthenic syndrome. Philadelphia, 1994. Drachman DB. Myasthenia gravis; medical progress. N Eng J Medicine 330, 1797, 1994


130

137.

Which of the following is characteristic of absence seizures (petit mal)? A. B. C. D.

Sudden cessation of ongoing conscious activity and loss of postural control without convulsive activity Pathognomonic electroencephalogram showing 3 Hz spike and wave discharges Difficulty of control with anti-epleptogenic medication Initial presentation generally in middle age ENDTEXT

Answer:

B

Rationale: Absence seizures have cessation of conscious activity without any convulsions or loss of postural control. These tend to be very brief, lasting seconds to sometimes a few minutes, and are usually diagnosed in young children. The EEG is pathognomonic and often shows that the child is having many more seizures than was evident. Antiepileptic drugs usually are effective for treatment.

Reference: Wilson, JD ed. Harrison's Principles of Internal Medicine. McGraw-Hill, Inc. 1991. p. 1969.


131

138.

Which of the following concerning Bell’s Palsy is true? A. B. C. D.

The transitory facial muscle paresis is usually due to a CNS vasospastic phenomenon This disorder has a peak incidence in men in the sixth decade of life Treatment for Bell's palsy include an antiviral combined with a glucocorticoid Diagnosis of Bell's palsy is made based on increased creatine phosphokinase (CPK) greater than 145mU/ml. secondary to low leve l rhabdomyolysis

Answer:

C

Rationale: Because the facial nerve has so many functions and is so complex, damage to the nerve or a disruption in its function can lead to many problems. Symptoms of Bell's palsy, which vary from person to person and range in severity from mild weakness to total paralysis, may include twitching, weakness, or paralysis on one or both sides of the face, drooping of the eyelid and corner of the mouth, drooling, dryness of the eye or mouth, impairment of taste, and excessive tearing in one eye. These symptoms usually begin suddenly and reach their peak within 48 hours. Other symptoms may include pain or discomfort around the jaw and behind the ear, ringing in one or both ears, headache, loss of taste, hypersensitivity to sound on the affected side, impaired speech, dizziness, and difficulty eating or drinking. Palsy occurs when the nerve that controls the facial muscles is swollen, inflamed, or compressed, resulting in facial weakness or paralysis. Exactly what causes this damage, however, is unknown. Most scientists believe that a viral infection such as viral meningitis or the common cold sore virus - herpes simplex - causes the disorder. Bell's palsy afflicts approximately 40,000 Americans each year. It affects men and women equally and can occur at any age, but it is less common before age 15 or after age 60. It disproportionately attacks pregnant women and people who have diabetes or upper respiratory ailments such as the flu or a cold. There is no cure or standard course of treatment for Bell's palsy. The most important factor in treatment is to eliminate the source of the nerve damage. Bell's palsy affects each individual differently. Some cases are mild and do not require treatment as the symptoms usually subside on their own within 2 weeks. For others, treatment may include medications and other therapeutic options. Recent studies have shown that steroids are an effective treatment for Bell's palsy and that an antiviral drug such as acyclovirused to fight viral infections-combined with an anti-inflammatory drug such as the steroid prednisone-used to reduce inflammation and swelling-may be effective in improving facial function by limiting or reducing damage to the nerve. Analgesics such as aspirin, acetaminophen, or ibuprofen may relieve pain. Another important factor in treatment is eye protection. Bell's palsy can interrupt the eyelid's natural blinking ability, leaving the eye exposed to irritation and drying. Therefore, keeping the eye moist and protecting the eye from debris and injury, especially at night, is important. Lubricating eye drops, such as artificial tears or eye ointments or gels, and eye patches are also effective. Facial massage and exercises may help prevent permanent contractures (shrinkage or shortening of muscles) of the paralyzed muscles before recovery takes place. Moist heat applied to the affected side of the face may help reduce pain. Other therapies that may be useful for some individuals include relaxation techniques, acupuncture, electrical stimulation, biofeedback training, and The American Board of Oral and Maxillofacial Surgery

132

vitamin therapy (including vitamin B12, B6, and zinc), which may help nerve growth. A diagnosis of Bell's palsy is made based on clinical presentation-including a distorted facial appearance and the inability to move muscles on the affected side of the face-and by ruling out other possible causes of facial paralysis. There is no specific laboratory test to confirm diagnosis of the disorder. Generally, a phy sician will examine the individual for upper and lower facial weakness. In most cases this weakness is limited to one side of the face or occasionally to the forehead, eyelid, or mouth. A test called electromyography (EMG) can confirm the presence of nerve damage and determine the severity and the extent of nerve involvement. An x-ray of the skull can help rule out infection or tumor. A magnetic resonance imaging (MRI) or computed tomography (CT) scan can eliminate other causes of pressure on the facial nerve.

Reference: th Fauci JD et al (Eds.): Harrison's Principles of Internal Medicine 14 Ed,.McGraw-Hill, New York, 1998 pp2378-9


133

139.

A patient who sustained a sharp blow to the chin was referred for evaluation of left TMJ pain. The patient complained of attenuated hearing on the left side. Otoscopic examination revealed blood in the middle ear. A positive Rinne test would suggest: A. B. C. D.

damage to cranial Nerve VIII. damage to Cranial Nerve VII. air conduction greater than bone conduction. bone conduction greater than air conduction.

Answer:

D

Rationale: A Rinne test involves evaluating a subject's ability to hear a vibrating tuning fork when it is held next to the ear and when it is placed on the mastoid process. Normally, air conduction is greater than bone conduction. A positive Rinne test exhibits diminished hearing acuity through air and somewhat heightened hearing acuity through bone, and is symptomatic of conduction deafness. Testing for damage to cranial nerve VIII vestibular function (such as cold water irrigation of the external auditory ca nal) often reveals nystagmus and for cochlear function reveals hearing loss. Therefore, a patient with VIII nerve disruption would have neither bone nor air conductive hearing. Injury to the facial nerve would be manifest by loss of facial animation and loss of taste on the involved side.

Reference: Handler, BH. History and Physical examination in PH Kwon, Daniel Laskin. Clinicians nd Manual of Oral and Maxillofacial Surgery, 2 edition. Quintessence Publishing, Chicago. Chapter 1, Page 7


134

140.

Which one of the following regarding muscular dystrophy is true? A. B. C. D.

This group of disorders is characterized by progressive abnormalities at the acetylcholine receptor site in the neuromuscular junction Patients with Duchenne’s muscular dystrophy may be safely managed with a nitrous/opioid anesthetic technique Succinylcholine causes prolonged muscle paralysis in this disorder Muscular dystrophy is a progressive, irreversible disease that usually leads to death in the early 50s due to cardiac failure

Answer:

B

Rationale: Muscular dystrophy (MD) has historically been diagnosed and categorized based on the age of onset, affected muscle groups, and genetic inheritance. Nearly one-third of new cases are spontaneous mutations, but two-thirds are inherited. Duchenne's is by far the most common form of MD and is due to abnormal and deficient dystrophin; other forms of MD may involve other myocyte proteins. Administration of a depolarizing muscle relaxa nt to a patient with MD would be likely to cause a massive potassium release that could precipitate c ardiac arrest due to hyperkalemia. MD patients, especially those with Duschenne's type, are susceptible to malignant hyperthermia and therefore the use of triggering agents such as depolarizing muscle relaxants (succinylcholine) and halogenated potent volatile anesthetics should be avoided. A nitrous oxide/opioid (“nitrous/narcotic”) anesthetic technique would be appropriate for such a patient. Prolonged muscle paralysis with succinylcholine is typical of a cholinesterase deficiency, not muscular dystrophy. These patients also have delayed gastric emptying time, with the associated risk of aspiration if the airway is not adequately protected. Demise from MD usually occurs in the 20's from respiratory failure.

Reference: Goldman:Cecil Textbook of Medicine, 22nd ed., Copyright 2004 W. B. Saunders Company, pp. 2387-2391


135

141.

Which of the following lab tests should be ordered when considering carbamazepine therapy for trigeminal neuralgia? A. B. C. D.

Complete blood count Serum electrolytes prothrombin time Serum calcium and phosphate

Answer:

A

Rationale: Carbamazepine is the treatment of choice for trigeminal neuralgia. This anticonvulsant provides relief to greater than 75% of trigeminal neuralgia patients. However, potential lifethreatening side effects include agranulocytosis, aplastic anemia, or thrombocytopenia. Changes in levels of serum electrolyte levels, clotting factors/profactorslevels, or calcium/phosphate are not generally thought to be within the side effect or complication profile of carbamazepine.

Reference: 2002 Ferri's Clinical Advisor, Fred Ferri, Mosby 2002 Edition, p. 717. Oral and Maxillofacial Pathology, Neville et. al., W.B. Saunders, 1995, pp. 628-9.


136

142.

A 35-year-old female patient with myasthenia gravis is scheduled for a bilateral saggital ramus osteotomy. When the patient is induced for general anesthesia, what reaction would you expect? A. B. C. D.

Reacts the same with all types of muscle relaxants Increased sensitivity to nondepolarizing relaxants Decreased sensitivity to nondepolarizing relaxants Increased sensitivity to depolarizing relaxants

Answer:

B

Rationale: Myasthenia gravis is an autoimmune disorder that occurs 1/20,000 persons and is characterized by injury of the acetylcholine receptors at the postsynaptic neuromuscular junction. These patients exhibit marked sensitivity to nondepolarizing muscle relaxants and slight resistance to succinylcholine

Reference: th Clinical Anesthesia Procedures of the Massachusetts General Hospital, 4 Ed., Davidson, et.al., Little Brown, 1993, pp. 166-8.


137

143.

The signs of causalgia (reflex sympathetic dystrophy) include: A. B. C. D.

hypoesthesia. pain of short duration. exacerbation of symptoms with a regional sympathetic block. skin flushing or pallor.

Answer:

D

Rationale: This complex regional pain syndrome typically occurs after a relatively minor injury resulting in a persistent, burning sensation with hyperesthesia and hyperpathia. This is thought to occur from a heightened sympathetic outflow. Peripheral vasodilation (skin flushing and warmth) or vasoconstriction (skin pallor and coolness) may occur. Diagn osis and treatment depend on pain relief following sympathetic blockade.

Reference: th Clinical Anesthesia Procedures of the Massachusetts General Hospital, 4 Ed., Davidson, nd et.al., Little Brown, 1993, pp. 595-6. Handbook of Neurosurgery, 2 Ed., Greenberg, M., th Greenberg Graphics, Inc., 1991, pp. 328-9. The Merck Manual, 17 Ed., Merck and Co., 1999, pp. 1372-3.


138

144.

Which of the following statements regarding temporal arteritis is true? A. B. C. D.

Predilection for adolescent females Rarely causes severe headaches Masticatory muscle pain during chewing Unresponsive to corticosteroid therapy

Answer:

C

Rationale: Temporal arteritis is a chronic inflammatory disease involving large arteries of the carotid system, particularly in those with a prominent elastica, occurring primarily in the elderly. This disorder commonly causes pain on mastication in the masseter, temporals, and tongue muscles. Estimated prevalence is about 1/1000 in patients > 50 yo with a slight predilection in females. Symptoms typically include a severe headache, scalp tenderness, and visual disturbances. It can cause blindness secondary to ischemic optic neuropathy in less than 20% of patients; but this occurrence is very rare after high-dose steroid treatment.

REFEENCES th The Merck Manual, 17 Ed., Merck and Co., 1999, pp. 438-9. 2002 Ferri’s Clinical Advisor, Fred Ferri, Mosby 2002 Edition, p. 682.


139

145.

An 89-year-old male presents with the following: akinesia, a resting ‘pill rolling’ tremor, rigidity and a shuffling gait. What is the pathophysiology of this condition? A. B. C. D.

Focal areas of demylination followed by reactive gliosis Lewy bodies present in the temproparietal lobe, cerebellum and basal ganglia Dopamine depletion in the substansia nigra of the basal ganglia Antibody-mediated neuromuscular receptor depletion

Answer:

C

Rationale: Parkinson's disease is the leading cause of neurologic disease in people older than 65-yearsold and affects approximately 1 million Americans. Typ ically it is characterized as an idiopathic movement disorder with akinesia, 'resting pill' rolling tremor and a shuffling gait. The primary pathogenesis is dopamine depletion in the substansia nigra of the basal ganglia. Lewy bodies (cytoplasmic inclusions) can be seen in Parkinson's disease however are localized to the cerebellum, basal ganglia, sympathetic ganglion and spinal cord and not usually the temporparietal lobe. Focal areas of demylination followed by reactive gliosis is seen in multiple sclerosis. Myesthenia gravis is an autoimmune disease causing muscular weakness from antibody mediated destruction of the acetylcholine receptor in the neuromuscular junction. Weakness is temporarily ameliorated by the administration of edrophonium, and is diagnostic for the disease.

Reference: Wichmann T et al. Parkinson's disease and the basal ganglia. Lessons from the laboratory and from neurosurgery. Neuroscientist. 1:236, 1995


140

147.

A 22-year-old male presents with a tumor compressing his optic chiasm. What visual field defect would you expect to see on physical examination? (Shaded areas indicate visual field deficit.)

Answer:

A

Rationale: The optic chiasm, contains axons from the nasal half of each retina, which look at the temporal half of the visual field and cross to the side contralateral to their eye of origin. The axons from the temporal retina remain uncrossed. Thus, if crossing fibers are destroyed in the optic chiasm, for example, by pressure from an expanding tumor (such as from the hypothalamus), the result is bitemporal hemianopsia., with the visual field de ficit illustrated in A. Answer B is homonymous hemianopia and is associated with severe contralateral optic tract defects or hemispheric lesion. Answer C is binasal hemifield defect. These defects are associated with lesions lateral to chiasm such as aneurysms; and other causes may include glaucoma or optic disk drusens. Answer D. is altitudinal hemianopia and is associated with occipital cortex ischemia and defects of the posterior occipital circulation.

Reference: Hirai T. et al. Loss of stereopsis with optic chiasmal lesions and stereoscopic tests as a differential test. Ophthalmology. 109(9):1692-702, 2002


141

148.

Which of the following headaches is described by unilateral, orbital or temporal distribution; intense, steady pain; onset usually within 2 or 3 hours of falling asleep; lacrimation, nasal congestion and then rhinorrhea? A. B. C. D.

Common migraine Classic migraine Cluster headache Tension headache

Answer:

C

Rationale: Cluster headaches have a much higher incidence in men than women. The pain is often retroorbital and is described as intense and boring in character. In addition to the above symptoms, there may be miosis, ptosis, flush and cheek edema which may last for two hours. It recurs nightly for weeks to months followed by months to years of relief from symptoms. Cluster headaches can sometimes be precipitated by vasodilating agents such as alcohol, nitroglycerin, or tyramine containing foods. Cluster headaches may be prophylaxed with ergot preparations at bedtime, amitriptyline or lithium carbonate. Classic migraine headache involves painless prodromes such as visual changes (scotoma) followed by (usually unilateral) throbbing headache lasting for 6 to 8 hours and often accompanied by fatigue and photophobia. Common migraines may not be as painful or intense as classic, and do not have a prodrome. Controversy revolves around “tension headaches,” as some think they are musculoskeletal in origin although some may have a partial vascular component.

Reference: Wilson, JD ed. Harrison's Principles of Internal Medicine. McGraw-Hill, Inc. 1991. p. 110111.


142

149.

Which of the following correctly couples the muscle with the nerve that innervates it? A. B. C. D.

tensor tympani - VIII posterior digastric -VII geniohyoid - IX superior oblique muscle -VI

Answer:

B

Rationale: The anterior digastric is innervated by the mylohyoid branch of the mandibular nerve (V), while the posterior belly of the digastric is innervated by the facial nerve (VII). They are actually 2 embryologically distinct muscles originating from branchial arches I a nd II, respectively. The tensor tympani receives its motor innervation from a branch of the mandibular nerve (V). The intrinsic (genioglossus and geniohyoid) and extrinsic tongue musculature receives motor input from the hypoglossal nerve (XII). The glossopharyngeal nerve (IX) provides special sensory innervation (taste) to the posterior tongue, innervates the carotid sinus, and carries autonomic input to the parotid gland and oropharynx. The abducent (VI) nerve innervates the lateral rectus muscle, while the trochlear nerve (IV) innervates the superior oblique muscle.

Reference: nd Goetz:Textbook of Clinical Neurology, 2 Ed. Elsevier, 2003. Textbook of Head and Neck nd Anatomy, 2 Ed. Hiatt, J and Gartner, L. Williams and Wilkins, 1987.


143

150.

During an elective genioplasty under deep sedation in your office, you note that the right mental nerve is severed. What type of injury is this according to the Seddon classification system, and how should it be repaired? A. B. C. D.

Neurotmesis; repair with perineurial neurorrhaphy Neurapraxia; repair with epineurial neurorrhaphy Axonotmesis; repair with perineurial neurorrhaphy Neurotmesis; repair with epineurial neurorrhaphy

Answer:

D

Rationale: The outer layer of the trigeminal nerve is the epineurium; this encloses the perineurium, which is the connective tissue surrounding groups of nerve fascicles. The endoneurium is the connective tissue layer surrounding individual fascicles within the perineurium. Seddon classified nerve injuries into neurapraxia (brief conduction loss due to manipulation with rapid recovery and no axonal degeneration), axonotmesis (more severe injury with axonal damage and demyelination) and neurotmesis (complete nerve transaction). Repair of this injury should be with 2 or 3 fine non-resorbing sutures placed in the e pineurial layer. Neurorrhaphy is the term for directly suturing 2 nerve ends together.

Reference: nd Peterson's Principles of Oral and Maxillofacial Surgery, 2 Ed. Miloro, M. (Ed.) BC Decker Inc, 2004, pp 819-837.


144

151.

A 43-year-old alcoholic male has acute onset confusion and amnesia and is brought to the ER for further evaluation. His toxicology screen is negative. His head CT shows some focal demyelination and gliosis of the thalamus, cerebellum and periaqueductal grey matter, without evidence of intracranial mass or bleeding. Further careful physical examination reveals bilateral lateral rectus palsy. What is his most likely diagnosis? A. B. C. D.

Korsakoff syndrome Wernicke’s encephalopathy Parkinson’s disease Diffuse axonal injury

Answer:

B

Rationale: Wernicke's encephalopathy is a finding often associated with chronic alcoholism and is thought to be due to thiamine (Vitamin B1) deficiency. It is associated with an acute confusional state, amnesia, ataxia and opthalmoplegia. The pathogenesis is due to demyleination, neuronal loss and gliosis of the thalamus, periaqueductal gray matter, cerebellum and cranial nerve III, VI and VII. Kosakoffs syndrome is also found in chronic alcoholism is the inability to form new memories and usually seen later than Wernickes encephalopathy. It too is associated with thiamine deficiency; however A is not the answer since the episode was of acute onset. Parkinson's disease is the most common neurologic disorder in patients over 65 years old and is a progressive movement disorder. Parkinson's disease is caused by the progressive loss of dopamine-producing neurons in the substantia nigra. Diffuse axonal injury is usually seen in patients in a prolonged coma, where neurologic recovery is slow.

Reference: Lieber CS. Medical disorders of alcohalism. N Eng J Med 333:1058, 1995. Victor M. Alcoholic dementia. Can J Neurol Sci 21:88, 1994


145

152.

From which cranial nerve does the parasympathetic fibers to the globe arise? A. B. C. D.

II III IV VI

Answer:

B

Rationale: In the parasympathetic autonomic nervous system, p re- and post-ganglionic fibers synapse close to the target organ, not close to the spinal cord, as occurs in the sympathetic nervous system. Parasympathetics to the eye synapse behind the globe in the ciliary ganglion and arise from CN III. Parasympathetics to the parotid synapse in the otic ganglion and arise from CN IX. Parasympathetics to the palatal minor salivary glands and nose synapse in the pterygopalatine ganglion and arise from CN VII. The neurotransmitter at this site is acetylcholine. The optic nerve (II) has no sympathetic component.

Reference: Vander, Sherman, and Luciano: “Human Physiology: The Mechanisms of Body Function”. McGraw-Hill, 1998, p.213-216. Romanes, GJ: “Cunningham's Manu al of Practical Anatomy”. Oxford Medical Publications, 1986.


146

153.

In treatment of diabetic ketoacidosis, maximal insulin effect is desired. This can be achieved through: A. B. C. D.

plasma insulin levels of 300-350 μu/ml. fluid restriction. IV insulin at a rate of 2-10 units/hour. sodium polystyrene resin.

Answer:

C

Rationale: Maximal insulin effect is reached with plasma levels of 20-200 u/ml. This can be accomplished (ideally in an intensive care setting) by administering IV insulin with an initial bolus of 10-15 units, followed by a continuous infusion at a rate of 2-10 units/hour. The ketoacidotic patient generally presents with decreased intravascular volume, requiring volume expansion and not fluid restriction. Although serum potassium is commonly elevated by ketoacidotic shift from intracellular fluids, total body potassium is often decreased and insulin can rapidly drop serum potassium to dangerously low levels. Often, potassium is judiciously given IV with insulin to keep serum potassium at a safe level.

Reference: nd Rose L, Kaye D:Internal Medicine for Dentistry 2 ed., C.V. Mosby, Saint Louis, 1990, pp 1124-1125. Donoff R: Massachusetts General Hospital Manual o f Oral and Maxillofacial Surgery C.V. Mosby, Saint Louis, 1987, pp 105-108. Stobo, et al: The Principles and Practice rd of Medicine 23 ed., Appleton & Lange, Stamford, 1996, pp 322-328


147

154.

A patient presents with the following oral/perioral conditions: metallic bad taste, halitosis, excessive salivation, stomatitis, and parotid swelling. These symptoms are most consistent with: A. B. C. D.

alcoholic cirrhosis. gastric ulcer. hepatocellular carcinoma. chronic renal failure.

Answer:

D

Rationale: Elevation of blood urea nitrogen in renal failure results in salivary ammonia excretion. Uremic stomatitis can occur in severe renal failure. Th is presents with symptoms of foul taste, halitosis, excessive salivation, as well as signs and symptoms of soft tissue stomatitis. Parotid as well as submandibular swelling may be seen in chronic renal failure with or without accompanying signs of stomatitis. Additionally, parotid swelling may be part of a malnutrition syndrome such as in alcoholism.

Reference: nd Rose L, Kaye D: Internal Medicine for Dentistry 2 ed., C.V. Mosby, Saint Louis, 1990, pp 587. Donoff R: Massachusetts General Hospital Manual of Oral and Maxillofacial Surgery C.V. Mosby, Saint Louis, 1987, pp 85-96. Stobo, et al: The Principles and Practice of rd Medicine 23 ed., Appleton & Lange, Stamford, 1996, pp 382-388


148

155.

After an orthognathic surgical procedure with prolonged induced hypotension and transfusion of two units of autodonated and one unit of banked red blood cells, you suspect olioguric acute renal failure. Which of the following is more predictive for your diagnosis? A. B. C. D.

Urine specific gravity elevated Urine sodium decreased Urine osomality elevated Serum creatinine increased

Answer:

D

Rationale: Patients in renal failure typically exhibit specific gravity which is isothenic (1.010) or less. Also, urine osmolality is low (<300) and sodium is high (>20mmol/L). Serum creatinine will be markedly elevated quickly in the initial (oliguric) phase of acute renal failure. This case of failure is probably due to ischemic hypoperfusion from prolonged hypotension. However, deposition of myoglobin from surgical insult or hemoglobin from transfusion may also be contributing to renal tubular dysfunction.

Reference: nd Rose L, Kaye D: Internal Medicine for Dentistry 2 ed., C.V. Mosby, Saint Louis, 1990, pp 754. Donoff R: Massachusetts General Hospital Manual of Oral and Maxillofacial Surgery C.V. Mosby, Saint Louis, 1987, pp 144. Stobo, et al: The Principles and Practice of Medicine rd 23 ed., Appleton & Lange, Stamford, 1996, pp 382-388


149

156.

Which of the following are predictive factors for the development of hepatorenal syndrome in patients with liver disease and ascites? A. B. C. D.

Low serum sodium Proteinuria Low plasma rennin Presence of hepatomegaly

Answer:

B

Rationale: Hepatorenal syndrome is a relatively frequent complication in cirrhotic patients with ascites that is associated with an extremely short survival. It is a complication of advanced cirrhosis characterized by renal failure due to severe renal vasoconstriction, increases in systemic blood pressure, and increased activity of endogenous vasoactive systems. Absence of hepatomegaly, high plasma renin activity, and low serum sodium concentration are predictors of hepatorenal syndrome occurrence in these patients. The fundamental problem in hepatorenal syndrome is renal ischemia secondary to hypotension and profound renal cortical vasoconstriction, leading to renal tubular dysfunction and proteinuria. Portal hypertension and its associated splanchnic arterial vasodilatation initiate a cascade of events leading to activation of systemic and local vasoconstrictors and depletion of local renal vasodilators. Therapy with vasopressin V(1) receptor and a lpha-adrenergic agonists, and plasma expanders, reverses type I and type II hepatorenal syndrome and improves survival. The first detailed description of HRS reported 9 patients with cirrhosis or acute hepatitis who developed renal failure without associated proteinuria and with very low urinary sodium excretion. On autopsy, these kidneys showed normal histology. It was later shown that kidneys from patients with HRS regain their function when transplanted into patients without cirrhosis and that HRS can be reversible following liver transplantation if done prior to irreversible renal damage.

Reference: Barada K, Hepatorenal syndrome: pathogenesis and novel pharmacological targets. Curr Opin Pharmacol 2004 Apr;4(2):189-97. Cardenas A, Arroyo V; Hepatorenal syndrome. Ann Hepatol 2003 Jan-Mar;2(1):23-9. Gines A, Escorsell A, Gines P, Salo J, Jimenez W, Inglada L, Navasa M, Claria J, Rimola A, Arroyo V, et al.; Incidence, predictive factors, and prognosis of the hepatorenal syndrome in cirrhosis with ascites. Gastroenterology 1993 Jul;105(1):229-36. Hecker R, Sherlock S; Electrolyte and circulatory changes in terminal liver failure. Lancet. 1956;2:1221-1225. Iwatsuki S, Popovtzer, M Corman J, et al.; Recovery from hepatorenal syndrome after orthotopic liver transplantation. N Engl J Med. 1973;289:1155-1159. Koppe M, Coburn J, Mims M, et al; Transplantation of cadaveric kidneys from patients with hepatorenal syndrome. Evidence for the functional nature of renal failure in advanced liver disease. N Engl J Med. 1969;280:1367-1371. The American Board of Oral and Maxillofacial Surgery

150

157.

You are called to the Emergency Department to evaluate a patient presenting with a right mandibular angle fracture. You note a history of severe alcoholism and anorexia in this cachetic individual. She exhibits peripheral edema, and is ataxic and confused. Which is the most likely diagnosis? A. B. C. D.

Korsakoff’s psychosis nutritional polyneuropathy Wernickes encephalopathy Wet beriberi

Answer:

D

Rationale: All of the listed disorders can be caused by the thiamine deficiency common in malnutrition, such as found in anorexic or alcoholic individuals. Chronically malnourished individuals can manifest with numerous metabolic and electrolyte disorders, and c areful nutritional diagnosis and support is vital in this patient population. Wet beriberi is a thiamine-depletion cardiovascular disorder with three major derangements: 1) peripheral vasodilatation with high-output cardiac failure 2) sodium retention and peripheral edema 3) biventricular heart failure. Wernicke's encephalopathy (cerebral beriberi) is an acutely evolving disease. Its most common manifestations include vomiting, nystagmus, ophthalmoplegia, and ataxia. Korsakoffs psycosis is primarily a disturbance of the ability to form new memories. Nutritional polyneuropathy, or dry beriberi, is a polyneuropathy involving the distal peripheral nerves. It primarily affects sensory innervation.

Reference: nd Rose L, Kaye D: Internal Medicine for Dentistry 2 ed., C.V. Mosby, Saint Louis, 1990, pp rd 744-745. Stobo, et al: The Principles and Practice of Medicine 23 ed., Appleton & Lange, Stamford, 1996, pp 931


151

158.

You are evaluating a patient who has a left submandibular infection of three days duration. His medical history is significant for hypertension and Type II diabetes mellitus controlled with oral hypoglycemic agents. Which of the following is true regarding this patient’s diabetes? A. B. C. D.

Treatment with oral medications should continue without change Concomitant infection will cause a decrease in serum glucose, oral medications should be discontinued Concomitant infection will cause an increase in serum glucose, insulin administration should be considered Serum potassium will rise in this patient and should be treated immediately

Answer:

C

Rationale: Infections cause gluconeogenesis and glycogenolysis. Even in Type II diabetics, exogenous insulin administration is often necessary in order to control glucose levels. Ketoacidosis leading to academia and hyperkalemia is not commonly seen even in severe hyperglycemia with Type II diabetics. However, in Type I individuals severely elevated glucose levels are indicative of insulinopenia. In severe insulin deficiency, glucose is not delivered through the cell membrane and intracellular metabolilsm uses proteins and fats, causing release of ketoacids. As ketoacidosis causes potassium shifts from inside the cells to the extracellular fluid, serum potassium values initially rise to critical levels, but total body potassium depletion occurs by renal potassium excretion.

Reference: nd Rose L, Kaye D: Internal Medicine for Dentistry 2 ed., C.V. Mosby, Saint Louis, 1990, pp 1124-1125. Donoff R: Massachusetts General Hospital Manual o f Oral and Maxillofacial Surgery C.V. Mosby, Saint Louis, 1987, pp 105-108. Stobo, et al: The Principles and Practice rd of Medicine 23 ed., Appleton & Lange, Stamford, 1996, pp 321-331


152

159.

Botulinum toxin type A (Botox) works by: A. B. C. D.

inhibition of acetylcholine release. postsynaptic binding of acetylcholine. blockade of calcium channels. blockage of epinephrine release.

Answer:

A

Rationale: Botulinum toxin type A blocks neuromuscular conduction by binding to receptor sites on motor nerve terminals, inhibiting the release of acetylcholine. This effect is temporary, usually lasting 3 to 6 months.

Reference: Coffield JA, et al. The site and mechanism of action of botulinum neurotoxin. In: Jankovic J, ed. Therapy With Botulinum Toxin. New York, NY Marcel Dekker; 1994:3-15.


153

160.

Resistance to Botulinum toxin type A (Botox) is increased by which of the following: A. B. C. D.

low doses of Botox. decreased frequency of treatments. decreased time interval between treatments. speed of injection.

Answer:

C

Rationale: Botox resistance is caused by high doses (>150 units), increased frequency of treatments, and decrease time interval between treatments, which become significant if given less than two months apart. This leads to antibody formation to the toxin.

Reference: Garcia A, Fulton JE. Cosmetic denervation of the muscles of facial expression with botulinum toxin A - a dose responses study. Dermatologic Surg. 1996; 22:39-43.


154

161.

The best approach to avoiding upper lid ptosis when treating forehead lines with Botox is: A. B. C. D.

injecting at the hairline and letting the toxin diffuse inferiorly. injecting only midline at the procerus muscle. injecting only the frontalis muscle. injecting at least 1 cm above the supraorbital rim.

Answer:

D

Rationale: Treatment of glabellar lines is easy to accomplish with minimal side effects. The most common side effect is lid ptosis, which is caused by diffusion of Botox to the superior lid muscles (levator palpebrae superioris). Lid ptosis is best done by staying 1cm above the supraorbital rim when injecting the corrugator muscles.

Reference: Carruthers A, Kiene K, Carruthers J. Botulinum A exotoxin use in clinical dermatology. J AM Acad Dermatol. 1996;34:788.


155

162.

The recommended dosage and number of injections for treating glabellar frown lines is: A. B. C. D.

20 units given with 5 injections. 40 units given with 10 injections. 40 units given with 5 injections. 20 units given with 10 injections.

Answer:

A

Rationale: The dosage for proper treatment of glabellar frown lines is 20 units given with 5 injections (4 units per injection): two injections in each corrugator muscle, and 0ne midline injection in the procerus muscle.

Reference: Carruthers JDA, Carruthers A. Treatment of glabellar frown lines with C. botulinum A exotoxin. Dermatol Surg. 1996;22:39-43.


156

163.

The muscle groups to be injected for treating glabellar frown lines with Botox include: A. B. C. D.

frontalis, corrugator, and procerus muscles. frontalis and procerus muscles. corrugator and procerus muscles. frontalis and corrugator muscles.

Answer:

C

Rationale: The treatment of glabellar frown lines with Botox requ ires injection of the procerus and corrugator muscle groups.

Reference: Carruthers JDA, Carruthers A. Treatment of glabellar frown lines with C. botulinum A exotoxin. Dermatol Surg. 1996; 22:39-43


157

164.

The minimum pore size for porous facial implants for resistance to bacterial infection is: A. B. C. D.

<1 micron. 10 to 25 microns. 26 to 50 microns. >50 microns.

Answer:

D

Rationale: Porous implants have the potential for ingrowth of bacteria that are introduced at the time of surgery or post-operatively from tissue breakdown. This occurs when the pore size is >1micron. Macrophages require a pore size of >50 microns to enter and engulf bacteria that have infected the implant. Therefore, the ideal porous implant would have pores smaller than 1 micron to avoid bacterial inoculation or >50 microns to allow macrophages to engulf the bacteria.

Reference: Cohen MS, Constantino PO, Friedman CD. Biology of implants used in head and neck surgery. Fac Plast Surg Clin North Am. 1999;9:17.


158

165.

Of the following, the best indication for collagen replacement therapy in lip augmentation is: A. B. C. D.

the scarred cleft lip. the aged lip with lack of definitive white roll. perioral rhytides. very small lips.

Answer:

B

Rationale: Collagen replacement therapy for lip augmentation is used to achieve fullness in the white roll area of the lip. Collagen has limited or no use in the scarred cleft lip or small lips. Perioral rhytides are best managed by other means (laser resurfacing, chemical peel, Restylane).

Reference: Niamtu, J. New lip and wrinkle fillers. Oral Maxillofacial Surg Clin N Am. 2005;17:17-28.


159

166.

When treating deep rhytides in the perioral region in a 68 year old female with sun damaged skin, the treatment of choice would be: A. B. C. D.

Botox. Myobloc. Bovine collagen. Restylane.

Answer:

D

Rationale: Deep perioral rhytides can be caused by many factors: habits (such as smoking), sun damage, loss of elastic collagen in the dermal layers, and overhanging, ptotic skin. Botox and Myobloc would have minimal effect in this scenario and are not recommended for patients over age 65. Bovine collagen can exhibit a severe inflammatory response. It is also short lived, lasting as little as two months. Restylane is longer acting with fewer side effects and would be the treatment of choice.

Reference: Kane, M. Botox injections for lower facial rejuvenation. Oral Maxillofacial Surg Clin N Am. 2005;17:41-49.


160

168.

The use of dermal or alloplastic material into the lips primarily achieves: A. B. C. D.

increased lip volume and vermillion exposure. enhanced white roll definition. reduced perioral rhytides. improved definition of cupid’s bow.

Answer:

A

Rationale: The use of autogenous or alloplastic materials into the lips primarily achieves an increase in lip volume and vermillion exposure. Improvement of white roll definition, perioral rhytides, or cupid's bow is inconsistent with implants.

Reference: Sykes, JM, Emery BE. Upper and lower lip augmentation with dermal autografts. Oper Tech Otolaryngol Head Neck Surg. 1995;6:307 Niamtu J. Advanta facial implants. Oral Maxillofacial Surg Clin N Am. 2005;17:29


161

169.

Patients undergoing chemical peel that are taking hormone replacement therapy are at increased risk of which of the following: A. B. C. D.

hypertrophic scar formation. delayed healing. persistent erythema. pigmentary changes.

Answer:

D

Rationale: Hormone replacement therapy may contribute to melanocyte activity and pigmentary changes. It is recommended that therapy be stopped one month prior to surgery to decrease incidence.

Reference: James R. Hupp, esthetic surgery of the aging face. Atlas of the Oral and Maxillofacial Surgery September 1998. Page 2


162

170.

A medium depth chemical peel agent will penetrate the skin to the level of the: A. B. C. D.

papillary dermis. upper reticular dermis. mid reticular dermis. lower reticular dermis.

Answer:

B

Rationale: Medium depth peel will penetrate to the level of the upper reticular dermis. Superficial peel will penetrate to the level of the papillary dermis. A deep depth peel will penetrate to the level of the mid reticular dermis.



163

171.

Which of the following medical conditions is a relative contraindication for the use of phenol peel: A. B. C. D.

pulmonary disease. gastric Disease. hepatic disease. endocrine disease.

Answer:

C

Rationale: Phenol is metabolized in the liver and excreted in the kidney, also has been associated with cardiac dysrhythmias. These diseases are relative contraindications to its use.



164

172.

Erythema that persists more than 3 month after chemical peels can be treated with: A. B. C. D.

antibiotic ointment. hydroquinone cream. topical steroid cream. CO2 laser.

Answer:

C

Rationale: Erythema up to three month is treated by observation. Erythema that persists after this period is treated with topical steroid creams. Hydroquinone is used to treat pigmentary changes. CO2 laser is of no benefit. Prolonged uses of antibiotic ointments have been implicated with persistent erythema.

Reference: James R. Hupp, esthetic surgery of the aging face. Atlas of the Oral and Maxillofacial Surgery September 1998. Page 2-22


165

173.

A 62-year-old female comes to your office and requests treatment of facial wrinkles. She has white skin. She states that she usually burns in the sun and tans minimally. Based on the above information, she can be classified as a Fitzpatrick type: A. B. C. D.

type I. type II. type III. type IV

Answer:

B

Rationale: The Class II skin type patient has a white skin color that usually burns and tans minimally. The Class I skin type always burns and never tans. The Class III skin type tans moderately and burns moderately. The Class IV skin type burns minimally and tans easily.

Reference: Obagi S: Skin resurfacing OMS knowledge update 2001


166

174.

Which of the following is a contraindication to CO2 laser resurfacing: A. B. C. D.

history of retinoid use 5 years ago. Fitzpatrick type II skin classification. history of hypertrophic scar formation. history of herpetic lesion.

Answer:

C

Rationale: A history of herpetic lesions is not a contraindication to CO2 laser skin resurfacing. Recent retinoid use can predispose a patient to hypertrophic scar formation. Fitzpatrick Class V would predispose a patient to pigmentary changes.

Reference: Robert A. Strauss, Steven A Guttenberg. Lasers in Oral and Maxillofacial Surgery. Oral and Maxillofacial surgery clinic may 2004 page 178-183


167

175.

A patient that undergoes laser skin resurfacing and is on Valacyclovir 1000mg once daily, develops a herpetic outbreak in the postoperative period. Which of the following is the recommended treatment? A. B. C. D.

Change to Acylovir 400mg three time/day Continue the current regimen for another two weeks Change to Valacyclovir 1000mg three times/day Treat the outbreak with Zithromax for 10 days

Answer:

C

Rationale: The dose should be increased to a herpes zoster dose. Herpetic outbreaks are very rare when the patient is taking antiherpetic medication but they do occur. Answer A is wrong since this is a prophylactic dose for acyclovir.

Reference: Robert A. Strauss, Steven A Guttenberg. Lasers in Oral and Maxillofacial Surgery. Oral and Maxillofacial Surgery Clinics. May 2004 page 178-183


168

176.

The chromophore for the Q-switched Nd-YAG laser is: A. B. C. D.

hemoglobin. water. melanin. protein.

Answer:

C

Rationale: A chromophore is a compound or chemical capable of selective light absorption. Lasers with different wavelengths of energy will be selectively absorbed by different chromophores, therefore allowing the laser to target specific structures. The chromophore of the CO2 laser is water. For the argon laser it is hemoglobin. For the Q-switched Nd-YAG laser it is melanin. Proteins are heterogenous and do not have a specific wavelength absorption range.

Reference: Guy A. Catone, Charles C. Alling. Laser Applications in Oral and Maxillofacial Surgery, WB Saunders, 1997.


169

177.

The “doll’s hair look” is usually seen with the use of which of the following hair transplant grafts: A. B. C. D.

punch graft. minigraft. micrograft. single hair transfer.

Answer:

A

Rationale: The doll's hair look is seen with the cylindrical plugs. The new techniques of minigrafts and micrografts eliminate this look.

Reference: James R. Hupp, esthetic surgery of the aging face. Atlas of the Oral and Maxillofacial Surgery September 1998. Page 39-51.


170

178.

Which on the following has no effect on the survival of adipocytes when harvesting fat: A. B. C. D.

harvesting site. harvesting technique. preparation technique. handling techniques.

Answer:

A

Rationale: The yield of adipocytes does not vary with the harvesting site. It is well established that the harvesting technique, preparation of fat for transfer, and handling techniques such as prolonged exposure to air can affect the yield of viable adipocytes.

Reference: Obagi S:Autologous Fat Augmentation for Addressing Facial Volume Loss: Oral Maxillofacial Surg Clin N Am 17:101-102, 2005.


171

179.

The modiolus: A. B. C. D.

influences the configuration of the nasolabial fold. is a confluence of three muscles of facial expression. is a confluence of nerves influencing expression. influences the configuration of the brow area.

Answer:

A

Rationale: The modiolus is an area of confluence of five muscles of facial expression, located lateral to the corner of the mouth. The five muscles are the levator anguli oris, zygomaticus major, risorius, platysma, and depressor anguli oris. This group of muscles is bound to the buccinator by connective tissue, and along with the cheekbone, represent the configuration of the nasolabial fold. The modiolus is not comprised of nerves and has no influence on the brow area.

Reference: Vigliante CE:Anatomy and functions of the muscles of facial expression: Oral Maxillofacial Surg Clin N Am 17:14-15, 2005.


172

180.

Your preoperative esthetic evaluation of a patient reveals brow ptosis, and an upper eyelid crease which is more than 12 mm above the upper eyelid margin with lid ptosis. This patient is best treated by: A. B. C. D.

transcutaneous upper eyelid blepharoplasty and b row lift. brow lift only, but only via a coronal approach. levator aponeurosis or Muller’s muscle surgery and brow lift. transconjunctival upper eyelid blepharoplasty and brow lift.

Answer:

C

Rationale: Transcutaneous blepharoplasty does not correct ey elid retraction, and occasionally will worsen the condition due to skin removal. Brow lift procedures will correct brow ptosis, but not lid ptosis. Surgery of the muscles of the upper eyelid is often performed to correct lid ptosis. Lid ptosis must be evaluated and corrected prior to a blepharoplasty procedure. A transconjunctival blepharoplasty will not correct eyelid retraction.

Reference: Karesh JW: Blepharoplasty. In: James Hupp, ed. Esthetic surgery of the aging face, Atlas of the Oral and Maxillofacial Surgery Clinics of North America. Se ptember 1998 Loeb R: Esthetic surgery of the eyelids. Springer-Verlag, New York 1989


173

181.

Where is Erb's point located? A. B. C. D.

3 cm inferior to the lobule of the ear and along the anterior border of the sternocleidomastoid. 3 cm inferior to the lobule of the ear and along the posterior border of the sternocleidomastoid. 6 cm inferior to the lobule of the ear and along the anterior border of the sternocleidomastoid. 6 cm inferior to the lobule of the ear and along the posterior border of the sternocleidomastoid

Answer:

D

Rationale: Erb's point is approximately 6 cm inferior to the lobule of the ear and along the posterior border of the sternocleidomastoid muscle, where the platysma crosses it obliquely. Remaining superficial to the fascia over the sternocleidomastoid muscle in this region ensures that injury to the greater auricular and accessory nerves is avoided.

Reference: Waite PD, Cuzalina LA: Rhytidectomy (Face Lift). In Fonseca R, Baker S, Wolford LM (eds). Oral and Maxillofacial Surgery, Vol 6, WB Saunders, Philadelphia, 2000


174

182.

At the corner of the mouth, the marginal mandibular branch of the facial nerve runs: A. B. C. D.

deep to the platysma until about 2 cm lateral to the corner of the mouth. superficial to the platysma until about 2 cm lateral to the corner of the mouth. deep to the platysma until about 4 cm lateral to the corner of the mouth. superficial to the platysma until about 4 cm lateral to the corner of the mouth.

Answer:

A

Rationale: The marginal mandibular branch of the facial nerve lies deep to the platysma in this area until about 2 cm lateral to the commissural of the mouth, at which stage, it penetrates the undersurface of the facial mimetic muscles, and is found more superficially.



175

183.

When planning a facelift procedure, the incidence of skin flap necrosis is found to be ______ times higher in smokers when compared to non-smokers. A. B. C. D.

5 8 12 15

Answer:

C

Rationale: Some surgeons consider smoking as an absolute contraindication; however, most recommend that smoking be stopped at least 1-2 weeks before surgery and for 2 weeks postoperatively. The overall complication rate for patients who continue to smoke is more than twice those who stop smoking.



176

184.

Where is McGregor's patch located? A. B. C. D.

an area near the posterior border of the sternocleidomastoid inferior to the ear lobule, where important nerves are found. an area near the zygomatic prominence where a plexus of vessels is found. an area near the antegonial notch and inferior mandible where the facial artery is found. the preauricular area where the facial nerve crosses the zygomatic arch.

Answer:

B

Rationale: MacGregor's patch is also known as the “bloody gulch.” It is named after the strong zygomaticodermal fibrous attachments that often present as skin dimpling or retraction. It is also pertinent because a plexus of vessels supplied by the facial artery and transverse facial artery becomes superficial in this area. Also, the b uccal nerve lies just deep to this danger zone, and the zygomatic branch of the facial nerve becomes more superficial in this area.

Reference: Waite PD, Cuzalina LA: Rhytidectomy (Face Lift). In Fonseca R, Baker S, Wolford LM (eds). Oral and Maxillofacial Surgery, Vol 6, WB Saunders Philadelphia, 2000.


177

185.

The nerve that is most commonly injured in face lift procedures is the: A. B. C. D.

marginal mandibular branch of facial nerve. spinal accessory nerve. greater auricular nerve. temporal branch of the facial nerve.

Answer:

C

Rationale: Injury to the facial nerve causing paralysis is rare, and reported only to occur in 0.53 to 2.6 % of patients. 85 % of motor nerve injuries resolve spontaneously, and results of surgical repair are unpredictable and not very encouraging. Injury to the greater auricular nerve is most common, and occurs in up to 7 % of patients. Temporary neuropraxia usually resolves in 2-4 months, and causes numbness/paresthesia around the inferior portion of the ear and surrounding skin. Transection of the nerve is best treated with immediate microanastomosis.

Reference: Waite PD, Cuzalina LA: Rhytidectomy (Face Lift). In Fonseca R, Baker S,Wolford LM (eds). Oral and Maxillofacial Surgery, Vol 6, WB Saunders, Philadelphia, 2000


178

186.

Which of the following best describes an ideal auriculocephalic angle: A. B. C. D.

10 to 20 degrees. 25 to 35 degrees. 40 to 50 degrees. 85 to 95 degrees.

Answer:

B

Rationale: In the “normal “ ear, the posterior wall of the conchal bowl is set at about 90 degrees to the mastoid. A second 90-degree angle is formed at the antihelical fold, and is called the scaphaconchal angle. These two angles, in combination with the curvature of the helix, set the auricle adjacent to the scalp at approximately 25-35 degrees.

Reference: Tanzer RC: Congenital deformities. In, Converse J (ed): Reconstructive Plastic Surgery, Vol nd 4, 2 edition, Philadelphia, WB Saunders, 1977.


179

187.

The main sensory innervation of the auricle is via the: A. B. C. D.

auriculotemporal nerve. cervical plexus branches. lesser occipital nerves and vagus branches. greater auricular nerve.

Answer:

D

Rationale: The sensory nerve supply is primarily from the anterior and posterior branches of the greater auricular nerve. This nerve travels 8 cm posterior to the postauricular crease. The auriculotemporal and lesser occipital nerves supply the conchal cavity and external auditory meatus, and auricular branches of the Vagus may supply the posterior wall of the external auditory meatus.

Reference: Owsley TG, Tejera TJ:Otoplastic surgery for the protruding ear. In, Fonseca R, Baker S, Wolford LM (eds). Oral and Maxillofacial Surgery, Vol 6, WB Saunders, Philadelphia, 2000


180

188.

Which of the following correctly describes the Mustarde technique for otoplasty: A. B. C. D.

Cartilage excision technique in a stepwise fashion to reduce a hypertrophic conchal wall. Postauricular approach to remove vestigial posterior auricular muscle and its ligament down to the mastoid fascia. Creation of a new antihelical fold by cartilage weakening and mattress sutures. Creation of a new antihelical fold at the expense of sharp cartilaginous ridges seen through the thin anterior auricular skin.

Answer:

C

Rationale: The Mustarde technique involves cartilage weakening and placement of a series of horizontal mattress sutures to create an antihelical fold. The Davis technique corrects conchal hypertrophy by stepwise cartilage excision. The Converse-Wood Smith technique involves several full-thickness cuts through the cartilage and suturing to form an antihelical fold; these sharp ridges can often be felt/seen through the thin anterior skin. The Furnas technique has a high incidence of relapse and is a postauricular approach, where the muscle is removed and sutures placed from the mastoid fascia to the ear cartilage.

Reference: Owsley TG, Tejera TJ:Otoplastic surgery for the protruding ear. In, Fonseca R, Baker S, Wolford LM (eds). Oral and Maxillofacial Surgery, Vol 6, WB Saunders, Philadelphia, 2000


181

189.

Perichondritis after otoplasty is most commonly caused by which of the following organisms: A. B. C. D.

Streptococcus pyogenes, Escherichia coli, Hemophyllus influenzae. Streptococcus pyogenes, Neisseria gonorrhea, Bacteroides species. Staphylococcus aureus, Hemophyllus influenzae, Bacteroides species. Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa.

Answer:

D

Rationale: Perichondritis occurs in the early postoperative period, and is usually related to an undetected or inadequately treated hematoma. Symptoms include pain, erythema, fever, and discharge. Treatment included high doses of antibiotics following wound cultures, and establishing adequate drainage. Massive cartilage destruction and severe ear deformities can result, despite aggressive treatment.

Reference: Owsley TG, Tejera TJ: Otoplastic surgery for the protruding ear. In, Fonseca R, Baker S, Wolford LM (eds). Oral and Maxillofacial Surgery, Vol 6, WB Saunders, Philadelphia, 2000.


182

190.

Most surgeons agree that reduction otoplasties can be safely performed in children after they have attained an age of: A. B. C. D.

2 years. 4 years. 6 years. 8 years.

Answer:

B

Reference: Owsley TG, Tejera TJ: Otoplastic surgery for the protruding ear. In, Fonseca R, Baker S, Wolford LM (eds). Oral and Maxillofacial Surgery, Vol 6, WB Saunders, Philadelphia, 2000


183

191.

When comparing the CO2 laser and Erbium: Yag laser for skin resurfacing for facial rhytids: A. B. C. D.

the hemostasis and collagen shrinkage achieved with a CO2 laser is the same as that of the Erbium:Yag laser. the hemostasis and collagen shrinkage achieved with the CO2 laser is greater than with the Erbium;Yag laser. the hemostasis and collagen shrinkage achieved with the CO2 laser is less than the Erbium:Yag laser. hemostasis and collagen shrinkage is not associated with either laser.

Answer:

B

Rationale: The CO2 and Erbium:Yag laser have different tissue effects. The thermal effects of the CO2 laser leaves a relatively wide zone of coagulation necrosis, which results in highly effective hemostasis, and produces immediate visible collagen shrinkage of up to 25 percent during irradiation. In contrast, the erbium laser has less extensive coagulation necrosis, which permits for more bleeding and only 1-2 percent of collagen shrinkage.

Reference: Tina, A. Cutaneous Resurfacing with CO2 and Erbium: Yag lasers: Preoperative, Intraoperative, and Postoperative Considerations. Plastic and Reconstructive Surgery. 103(2), 619-632. 1999


184

192.

Which of the following chemical skin resurfacing agents is associated with dysrythmias? A. B. C. D.

Glycolic Acid Trichloroacetic acid Phenol Salicyclic acid

Answer:

C

Rationale: Phenol is rapidly absorbed through the skin and metabolized through the liver, and excreted by the kidney. It can lead to renal failure and hepatotoxicity, and can directly irritate the myocardium, inducing dysrythmias.

Reference: Demas, P, Braun, T. Chemical Skin Resurfacing. Atlas of Oral and Maxillofacial Surgery. 6(2) 1-22. 1998.


185

193.

When injecting Botox for reduction of Crow’s feet, the surgeon should: A. B. C. D.

inject the agent at least 2cm away from the lateral canthus to prevent paralysis of the orbicularis oculi muscle. inject the agent at the lateral orbital rim to prevent paralysis of the inferior rectus muscle. inject the agent just medial to the lateral orbital rim to prevent paralysis of the lateral rectus muscle. inject the agent at least 1cm from the lateral orbital rim to prevent paralysis of the lateral rectus muscle.

Answer:

D

Rationale: Crow's feet are addressed by injecting the orbicularis oculi muscle in a semi-lunar pattern. Care is taken to maintain a 1cm distance from the lateral orbital rim to avoid diploplia from inadvertent injection into the lateral rectus muscle.

Reference: Obagi S. Correction of surface deformities; Botox, soft-tissue fillers, lasers and intense pulsed light, and radiofrequency. Atlas of Oral and Maxillofacial Surgery Clinics of North America. 12. 271-297. 2004


186

194.

In treatment planning for alloplastic cheek augmentation, the ideal position of the cheek eminence is located: A. B. C. D.

15mm lateral and 10mm inferior to the lateral canthus. 20mm inferior and 10mm lateral to the most lateral point o f the supraorbital rim. 10mm lateral and 15-20mm inferior to the lateral canthus. 5mm superior and 10-15mm superior to the most lateral point at the infraorbital rim.

Answer:

C

Rationale: The most ideal position of the cheek eminence is located 10mm lateral and 15-20mm inferior to the lateral canthus. This mark aids in the proper superior-inferior and lateral positioning of the cheek implant.

Reference: Epker B. Maxillofacial contour esthetic deformities. Atlas of Oral and Maxillofacial Surgery clinics of North America. 12. 75-89.2004


187

195.

How many fat pads are excised or reduced during an upper eyelid blepharoplasty with fat debulking? A. B. C. D.

1 2 3 4

Answer:

B

Rationale: The upper eyelid contains 2 fat pads: the medial and central fat pads which may be removed during upper eyelid blepharoplasty. The lower eyelid contains 3 fat pads: the medial, central, and lateral fat pads. In the upper eyelid, the lateral compartment is occupied by the lacrimal gland and should not be disturbed during upper eyelid blepharoplasty.

Reference: Jarecki HL, Lucarelli MJ, Lemke BN: Blepharoplasty. Peterson's Principls of Oral and nd Maxillofacial Surgery 2 Edition. 2004: pp 1317-1344


188

196.

Injury to the levator aponeurosis during upper eyelid blepharoplasty may result in which postoperative complication: A. B. C. D.

dry eye. diplopia. ptosis. lagophthalmos.

Answer:

C

Rationale: Injury to the upper eyelid levator aponeuroris may result in ptosis. Dry eye may result from resection of the lacrimal gland. Diplopia is a complication of lower lid blepharoplasty. And Lagophthalmos results from excessive skin/muscle excision.

Reference: Jarecki HL, Lucarelli MJ, Lemke BN: Blepharoplasty. Peterson's Principls of Oral and nd Maxillofacial Surgery 2 Edition. 2004: pp 1317-1344


189

197.

The upper eyelid crease (supratarsal fold) is produced by which anatomic structures: A. B. C. D.

the insertion of the levator palpebrae aponeurosis into the skin. the insertion of the superior rectus to the tarsal plate. the superior oblique muscle relationship to the trochlea. the orbital septum attachment to the orbital rim.

Answer:

A

Rationale: The supratarsal fold is produced by the insertion of the levator aponeurosis into the skin of the upper eyelid.

Reference: Delgado JA, Jacobs JL, Baylis HI, Goldberg RA: Blepharoplasty and Periorbital Surgery. Facial Plastic Surgery Clinics of North AmericA.1998: pp 4 1-58


190

198.

Postoperative bleeding after blepharoplasty may result in blindness by which mechanism: A. B. C. D.

compression of the optic nerve. compression of the central retinal artery. traumatic optic neuropathy. cortical blindness.

Answer:

B

Rationale: Orbital hematoma may develop after orbital fat excision. This may result in increased intraorbital pressure with compression of the central retinal artery causing blindness.

Reference: Hatt M: Ophthalmic Plastic and Reconstructive Surgery. New York. Thieme Inc. pp 153159.


191

199.

An advantage of transconjunctival lower lid blepharoplasty over transcutaneous lid blepharoplasty would be: A. B. C. D.

ease of performing skin excision. decreased incidence of lower lid retraction. ease of performing muscle excision. decreased incidence of entropion.

Answer:

B

Rationale: Transconjunctival blepharoplasty has been shown to have a significantly reduced risk of lower lid retraction.

Reference: Jacono AA, Moskowitz B:Facial Plastic Surgery. Vol 17(1). 2001:pp 21-27.


192

200.

During alloplastic mandibular angle augmentation, the implant is placed in which position: A. B. C. D.

supraperiosteal, deep to the masseter. superficial to the masseter muscle. superficial to the buccinator muscle. subperiosteal, deep to the masseter.

Answer:

D

Rationale: Mandibular angle augmentation may be performed by an intraoral approach by placing the implant in a subperiosteal position, deep to the masseter muscle.

Reference: Epker BN. Alloplastic Esthetic Facial Augmentation. Peterson's Principals of Oral and nd Maxillofacial Surgery 2 Edition. 2004:1435 – 1447.


193

201.

When planning an advancement genioplasty, the osteotomy should be designed: A. B. C. D.

1 mm inferior to the mental foramen. 3 mm inferior to the mental foramen. 5 mm inferior to the dentition. 7 mm inferior to the dentition.

Answer:

C

Rationale: The osteotomy should be designed to avoid the inferior course of the mental foramen and must be placed 5 mm below the mental foramen.

Reference: Hwang KL, Song YB, Chung IH. Vulnerability of the Inferior Alveolar Nerve and Mental Nerve during Genioplasty:an anatomic study. J Craniofac Surg 200516(1):10-4, 2005.


194

202.

Which of the following agents may be used for skin preparation prior to cosmetic blepharoplasty? A. B. C. D.

Povidone-iodine solution Chlorhexidine solution Hydrogen peroxide Castille solution

Answer:

A

Rationale: Povidone-iodine solution is not harmful to the eye. Chlorhexidine has the potential to lyse corneal epithelium. Hydryogen peroxide is a distractor. Castille solution has no therapeutic benefit as a presurgical antimicrobial. Solutions containing alcohol can be harmful to the eye.

Reference: Fonseca, R.J., et al: Oral and Maxillofacial Surgery, Volume 6: Cleft/Craniofacial/Cosmetic Surgery. pp 355


195

203.

In laser resurfacing blepharoplasty, the snap and distraction tests are used to help evaluate: A. B. C. D.

extraocular muscle motion. eyelid laxity. epithelial keratinization. conjunctivitis.

Answer:

B

Rationale: The snap and distraction tests are used prior to laser blepharoplasty resurfacing to identify patients who may be at risk for lower lid ectropion.

Reference: Guttenberg SA, Emery RW. Laser Cosmetic Skin Resurfacing: Superpulse Perspective. Oral and Maxillofacial Surgery Clinics of North America. May 2004. Vol 16(2): 197-213.


196

204.

With the closed approach to rhinoplasty, the intercartilagenous incision is used most often when: A. B. C. D.

dorsal access is needed with little or no tip alteration. for access to perform lateral nasal osteotomies. switching to the open approach is anticipated. complete tip exposure is necessary.

Answer:

A

Rationale: The intercartilagenous incision is used to access the nasal dorsum when little or no tip alteration is necessary in the closed rhinoplasty approach. The intracartilagenous approach will facilitate a cephalic trimming of the lower lateral cartilage. A marginal incision combined with a transcolumellar incision is used for the open rhinoplasty. Complete tip exposure, particularly to view the lower lateral cartilages in their correct anatomic position is best done with the open approach.

Reference: Rhinoplasty:Calhoun KH, in Atlas of Head and Neck Surgery-Otolaryngology:Baily BJ, Calhoun KH, Coffey AR, Neely JG, Lippencott-Raven, Philadelphia, pp. 450-451, 1996.


197

205.

When evaluating the nose from a lateral view, the ideal range of columellar show is: A. B. C. D.

between 0 to 1mm. between 2 to 4mm. between 5 to 7mm. between 8 to 10mm.

Answer:

B

Rationale: Columellar show is the amount of columella which is seen below the alar rim. This is normally in the range of 2 to 4mm. Excessive or insufficient columellar show should be addressed in esthetic rhinoplasty.

Reference: Nasal-Facial Analysis, McGraw-Wall BL, in Atlas of Head and Neck SurgeryOtolaryngology: Baily BJ, Calhoun KH, Coffey AR, Neely JG, Lippencott-Raven, Philadelphia, pp. 442-443, 1996.


198

206.

The spreader graft in rhinoplasty surgery is placed: A. B. C. D.

between the lower lateral and upper lateral cartilages between the upper lateral cartilage and nasal septum between the lower lateral cartilage and nasal septum between the two medial crus

Answer:

B

Rationale: The internal nasal valve is formed by the junction of the upper lateral cartilage and the nasal septum. Spreader grafts are placed to increase the size of this junction, hence improving nasal airway breathing, and in some cases, nasal esthetics.

Reference: Rohrich R, et al.: Use of Spreader Grafts in External Approach to Rhinoplasty. In, Clinics in Plastic Surgery, 255-262, 1996.


199

207.

The hemi-transfixion incision differs from the complete transfixion incision because: A. B. C. D.

the hemi-transfixation incision gives better access to the nasal dorsum, the hemi-transfixation incision provides better access to the anterior nasal spine. the hemi-transfixion incision preserves more nasal tip support. the hemi-transfixion incision is more often combined with the transcolumellar incision.

Answer:

C

Rationale: The transfixion and hemitransfixion incision provide access to the caudal septum in endonasal rhinoplasty. The complete transfixion incision separates the medial crura from the septum. The hemitransfixion incision is only made on one side, and usually stops short of the anterior nasal spine, preserving tip support. The nasal dorsum is not approached with the transfixion incision. The transcolumellar incision is used in an open approach and is not normally combined with either the transfixion or hemi-transfixion incision.

Reference: Sublabial and Septal Incisions: Renner G, in Atlas of Head and Neck SurgeryOtolaryngology: Baily BJ, Calhoun KH, Coffey AR, Neely JG, Lippencott-Raven, Philadelphia, pp. 853-853, 1996.


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