1. Following trauma, bluish-grey discolouration of the crown is due to A. external resorption. B. pulpal hemorrhage. C. discoloured composite restoration. D. chromogenic bacteria. Answer: B Intrapulpal hemorrhage and lysis of erythrocytes are a common result of traumatic injury to a tooth. Blood disintegration products, presumably iron sulfides, flow into the tubules and discolor the surrounding dentin. If the pulp becomes necrotic, the discoloration persists and usually becomes more severe with time. If the pulp recovers, the discoloration may be reversed, with the tooth regaining its original shade. 2. Which of the following is LEAST likely to cause pain? A. Carious pulp exposure. B. Chronic hyperplastic pulpitis (pulp polyp). C. Acute pulpitis. D. Apical periodontitis. A patient experiences pain and some gingival Answer: B Chronic hyperplastic pulpitis also called pulp polyp, is an inflammatory proliferative response to infection of pulp tissues in a tooth with a very good blood supply and rapid carious destruction. It is essentially a pyogenic granuloma of the pulp tissue. It is usually painless but may bleed easily because of vital vascular supply. 3. A patient experiences pain and some gingival swelling in the anterior segment of the mandible. The mandibular lateral incisor has a shallow restoration, is tender to percussion and gives a positive response to the electric pulp tester. There is some mobility. The most likely diagnosis is A. acute apical abscess. B. acute serous pulpitis. C. lateral periodontal abscess. D. acute suppurative pulpitis. E. chronic ulcerative pulpitis. Answer: C A lateral periodontal abscess is a result of rapidly-growing bacteria within a periodontal pocket. Pain characteristics of a lateral periodontal abscess are very similar to those acute periapical
periodontitis. The pain is continuous, and well localized and is exacerbated by biting on the affected tooth. The swelling is usually located more coronally than in acute periapical lesions. The tooth is sensitive to percussion and may be mobile and slightly extruded. The tooth pulp is usually vital. 4. Which one of the following statements is true as defined in endodontics? A. Overfilling refers to the incomplete filling of the canal system with a surplus of material extruding beyond the apical foramen. B. Underfilling refers to the complete filling of the canal space, but leaving voids in the pulp chamber for possible recontamination or infection. C. Overextension refers to the extrusion of filling material through an accessory canal. D. Underextension refers to the vertical extent of the filling material regardless of its completeness of obturation. E. All of the above. Answer: D Overfilling denotes “total obturation of the root canal space with excess material extruding beyond the apical foramen.” Overextension, on the other hand, may also denote extrusion of filling material beyond the apical foramen but with the caveat that the canal has not been adequately filled and the apex has not been sealed Underfilling refers to the incomplete filling of the canal space Underextension refers to the vertical extent of the filling material regardless of its completeness of obturation. 5. After completion of endodontic chemomechanical debridement you can expect to have 1. removed all tissue from the entire root canal system. 2. caused some temporary inflammation. 4. completely sterilized the root canal. 4. left some areas of the root canal system incompletely cleaned. A. (1) (2) (3) B. (1) and (3) C. (2) and (4) D. (4) only. E. All of the above Answer: C The complex anatomy of the root canal system (e.g. lateral canals)
makes debridement difficult, especially in the apical delta region. Furthermore, bacteria have been shown to invade dentinal tubules and thus they may not be removed totally by chemomechanical debridement. Thorough cleaning, shaping and irrigation with disinfectants may not result in a completely sterile root canal system. Leakage cannot be totally prevented by any material/method available today, percolation of nutrient-rich fluid followed by bacterial regrowth may occur. Temporary inflammation may occur. 6. Which of the following methods of instrument sterilization uses the lowest temperature? A. Steam autoclave. B. Dry heat oven. C. Ethylene oxide method. D. Glass bead sterilizer. E. Alcohol autoclave. Answer: C (1) Steam autoclave works by subjecting instruments to high pressure saturated steam at 121 °C for around 15–20 minutes. (2) The proper time and temperature for Dry-Heat sterilization is 160°C (320°F) for 2 hours or 170°C (340°F) for 1 hour. (3) Glass bead sterilizer is a chair-side sterilization of small dental hand instruments, especially endodontic files. The files were placed in 225 °C or 250 °C heated glass bead sterilizers for 10-15 sec. (3) Ethylene oxide gas is commonly used to sterilize objects sensitive to temperatures greater than 60 °C and / or radiation such as plastics, optics and electrics. Ethylene oxide method is generally performed between 30 °C and 60 °C with relative humidity above 30% and a gas concentration between 200 and 800 mg/l, and needs for at least three hours. 7. When root canals are treated topically with antibiotics rather than with disinfectants 1. a greater success rate results. 2. the same rules of mechanical preparation and filling must be observed. 3. treatment may be completed in fewer appointments. 4. there is greater assurance that all microorganisms are destroyed. 5. there is a danger of sensitizing patients to antibiotics. A. (1) (3) (4) B. (2) (4) (5)
C. (1) (2) (3) D. (2) and (5) E. All of the above. Answer: D The use of antibiotic in root canal treatment has not been approved to show greater success then using disinfectant. The potential risk of adverse systemic effects, such as allergic reactions, toxicity, various side effects and the development of resistant strains of microbes may happen. And bacteria have been shown to invade deep into dentinal tubules and thus they may not be destroyed totally. 8. The antibiotic of choice for infections of pulpal origin is A. penicillin V. B. lincomycin. C. erythromycin. D. tetracycline. Answer: A Penicillin is the gold standard in treating dental infections. Penicillin is bactericidal and active against replicating bacteria often encountered in odontogenic infections. Aerobic and anaerobic microorganisms are susceptible to penicillin. Penicillin VK has greater oral absorption than penicillin G. 9. Endodontic therapy is CONTRAINDICATED in teeth with A. inadequate periodontal support. B. pulp stones. C. constricted root canals. D. accessory canals. E. curved roots. Answer: A Most contraindications of Periapical surgery are relative, and they are usually limited to three areas: (1) the patient’s medical status, (2) anatomic considerations, and (3) the dentist’s skills and experience. Few absolute contraindications exist such as (1) Unrestorable tooth (2) lack of necessary osseous support for the remaining root or roots. (2) Fused roots or roots in unfavorable proximity to each other. (3) Remaining root or roots endodontically inoperable. (4) Lack of patient motivation to properly perform home-care procedures. 10. Periapical surgery is CONTRAINDICATED for a tooth that has a
A. large periapical rarefaction. B. fistula related to a periapical lesion. C. vertical root fracture. D. fracture of the root apex and a necrotic pulp. E. a post and core retained crown. Answer: C Most contraindications of Periapical surgery are relative, and they are usually limited to three areas: (1) the patient’s medical status, (2) anatomic considerations, and (3) the dentist’s skills and experience. Few absolute contraindications exist such as (1) Unrestorable tooth (2) lack of necessary osseous support for the remaining root or roots. (2) Fused roots or roots in unfavorable proximity to each other. (3) Remaining root or roots endodontically inoperable. (4) Lack of patient motivation to properly perform home-care procedures.
11. A patient telephones and tells you he has just knocked out his front tooth but that it is still intact. Your instructions should be to A. put the tooth in water and come to your office at the end of the day. B. wrap the tooth in tissue and come to your office in a week's time. C. put the tooth in alcohol and come to your office immediately. D. place tooth under the tongue and come to your office immediately. E. place the tooth in milk and come to your office immediately. Answer: E Dental avulsion is a dental emergency, in which immediate management (within 20–40 minutes of injury) affects the prognosis of the tooth. Although the best treatment for an avulsed tooth is immediate replantation, It is difficult for the non-professional person. The most often recommended storage media are: milk saliva, physiologic saline and pH balanced cell preserving fluids. The most optimum storage media is called Hank’s Balanced Salt Solution (HBSS), followed by milk. Tap water is a bad storage medium, because it causes rapid cell lysis, similar to dry storage. Saliva, for a small period of time is effective, but contains microorganisms and it has low osmolality, which adversely affects the viability of cells in the periodontal ligament.[/color]
12. The placement of a retentive pin in the proximal regions of posterior teeth would MOST likely result in periodontal ligament perforation in the A. mesial of a mandibular first premolar. B. distal of a mandibular first premolar. C. distal of a mandibular first molar. D. mesial of a mandibular first molar. Answer: D Characteristics of mandibular first molar (1) Buccal aspect •.MB cusp is the widest than DB and D cusps •.MB and DB grooves extend to buccal surface (2) Lingual aspect •.ML and DL cusps of equal size • Lingual groove extends midway on lingual surface • Cervical 1/3 is flat or concave (3) Proximal aspect • Both mesial and distal contact areas are at the middle third (4) Occlusal aspect • The outline is pentagonal shaped, Broader buccally than lingually • 5 Cusps: two lingual cusps and three buccal cusps (MB, DB, and distal—in order of decreasing size) (4) Root • 98% two roots: mesial and distal • Chance of two canals: 6.7%, three canals: 65%. Four canals: 29% 13. For a cast gold restoration, a gingival bevel is used instead of a shoulder because a bevel 1. protects the enamel. 2. increases retention. 3. improves marginal adaptation. 4. increases the thickness of gold. A. (1) (2) (3) B. (1) and (3) C. (2) and (4) D. (4) only E. All of the above. Answer: B The gingival bevel preparation for a cast gold restoration removes the unsupported tooth structure (enamel) and provides a burnishable margin for the metal to reduce marginal discrepancies.
14. In permanent teeth, two pulp canals are most commonly found in the A. distobuccal root of maxillary molars. B. distal root of mandibular first molars. C. palatal root of maxillary first premolars. D. mesial root of mandibular first molars Answer: D 60-70% mandibular first molars have two canals in the mesial root. Among these teeth around 60 % have the mesial canals remained divided throughout the length, and around 40 have the mesial canals converged into one in the apical third with a common foramen. 15. Firm contact between approximating teeth is important because it A. locates the marginal ridges of each tooth. B. keeps the teeth from having any movement during function. C. insures proper cusp form and increases masticatory efficiency. D. stabilizes the dental arches and gives protection to the gingival papillae Answer: D The main function of teeth contact areas is to stabilizes the arch, prevents food impaction and to protect the gingival papilla. 16. In determining the ideal proximal outline form for a Class II amalgam cavity preparation in a molar the 1. axial wall should be 1.5mm deep. 2. gingival cavosurface margin must clear contact with the adjacent tooth. 3. proximal walls diverge occlusally. 4. facial and lingual proximal cavosurface margins must just clear contact with the adjacent tooth. A. (1) (2) (3) B. (1) and (3) C. (2) and (4) D. (4) only E. All of the above. Answer: C The ideal proximal outline form of a Class II amalgam cavity preparation in a molar: (1) Broken buccal and lingual proximal contact, with 0.3-0.5mm
clearance (just allow the tip portion of the explore pass) (2) Open gingival contact with 0.5mm clearance (3) Convergent buccal and lingual wall (4) Pulpoaxial wall parallel to gingival cavosurface and 1.25-1.5mm in depth (5) Axio-pulpal lingle angle beveled (6) Gingival margin beveled to remove unsupported enamel 17. A rubber dam should be used in A. pulp capping procedures. B. amalgam placement. C. composite placement. D. removing carious dentin from deep lesions. E. all of the above Answer: E The purpose of using rubber dam placement is to improve overall quality of dental treatment: (1) facilitate visibility (2) moisture control (3) improve material property (4) patient protection. (5) prevent salivary contamination. Etc. 18. The air-water spray used as a coolant in high speed cutting of a cavity will 1. decrease pulp damage. 2. reduce frictional heat. 3. keep the operating site clean. 4. reduce clogging of cutting instruments. A. (1) (2) (3) B. (1) and (3) C. (2) and (4) D. (4) only E. All of the above. Answer: E Frictional heat is produced whenever a rotary bur or stone contacts tooth structure. Without a coolant, vital dental will be scorched and pulp is injured. The air-water spray with sufficient volume also helps to remove the debris to keep the operating site clean and to reduce clogging of cutting instruments. 19. Which of the following may affect the results of electric pulp testing? A. Emotional factors. B. Pain threshold.
C. Analgesics. D. Recent trauma. E. All of the above. Answer: E Electric pulp testing (EPT) works on the premise that electrical stimuli cause an ionic change across the neural membrane, thereby inducing an action potential with a rapid hopping action at the nodes of Ranvier in myelinated nerves. A “tingling” sensation will be felt by the patient once the increasing voltage reaches the pain threshold, but this threshold level varies between patients and teeth, and is affected by factors such as individual age, emotional factors, pain perception, pain threshold, tooth surface conduction, and resistance, analgesic using, recent trauma, orthodontic treatment, etc 20. Which of the following statements is/are true? 1. Radiographs cannot differentiate between infected and noninfected periapical lesions. 2. A definitive diagnosis of an apical lesion cannot be made on radiography alone. 3. Periapical radiolucencies are not always indicative of loss of pulp vitality. 4. A periapical radiograph can be used to locate the buccal bone level. A. (1) (2) (3) B. (1) and (3) C. (2) and (4) D. (4) only E. All of the above. Answer: A (1) Radiographs cannot differentiate between infected and noninfected periapical lesions. For example, acute apical periodontitis may have no radiographic change. (2) A definitive diagnosis of an apical lesion cannot be made on radiography alone. (3) Radiolucency image, such as mental foramen, periapical Cemento-osseous dysplasia are associated with vital teeth. (4) One of the limitation of radiographic image is that the three dimensional object interpreted by two dimensional images. A periapical radiograph can not be used to locate the buccal bone
level as the superimposition of buccal and lingual structures. 21. A positive and prolonged reaction to a heat stimulus indicates that the pulp is A. necrotic. B. in an early hyperemic state. C. normal. D. irreversibly damaged Answer: D The pulp status as the sequence of dental caries (dental trauma, operative procedure, etc) includes pulp hyperemia, acute pulpitis, chronic pulpitis ans acute periapical abscess. Pulp hyperemia is a reversible condition. A very typical pain is felt due to hot or cold stimulus and the pain is transient, which subsides after remove the stimulus. Irrevisible pulp damage results in a positive and prolonged reaction to a heat/ stimulus. Necrotic pulp has no response to cold/heat stimulus. 22. Which of the following is/are associated with the presence of microorganisms in the bloodstream? A. Anachoresis. B. Cavernous sinus thrombosis. C. Bacteremia. D. All of the above. Answer: D Anachoresis.is the localization and fixation of bloodborne bacteria and other materials in zones of inflammation. Cavernous sinus thrombosis is the formation of a blood clot within the cavernous sinus. Bacteremia is the presence of bacteria in the blood. 23, Which of the following is/are true regarding a tooth filled with a formaldehyde-containing paste? A. Formaldehyde-containing pastes remain non-approved. B. The drug manufacturer may be liable, along with the dentist. C. Formaldehyde-containing pastes have a high antigenic potential. D. There are cases on record of parasthesia following overextrusion of such a paste in the vicinity of the mandibular nerve. E. All of the above Answer: E The formaldehyde component of the medications have been implicated for exerting potentially harmful systemic and local effects. Formaldehyde-
containing pastes has been shown to have a high incidence of nerve toxicity. Zinc oxide–eugenol (ZOE) paste and ZOE paste modified with paraformaldehyde have been found to alter dog pulp tissue, making it antigenetically active. Studies have shown that formaldehyde-containing sealers were highly toxic. Reaction to the physical and chemical trauma of formaldehyde periradicularly can be very severe and there are case reports of parasthesia following overextrusion of such a paste in the vicinity of the mandibular nerve. Formaldehyde-containing pastes remain non-approved. 24. The desired termination point of apical root canal preparation when performing endodontic treatment on a vital tooth is A. 0.5 to 1mm short of the radiographic apex. B. 3mm short of the radiographic apex. C. slightly through the apical foramen. D. to the point where the patient feels sensation. Answer: A When performing endodontic treatment on a vital tooth, the canal is generally shaped into a round tapered preparation. Preparation terminates at the cementodentinal junction, 0.5 to 1.0 mm from the radiographic apex. 25. Which one of the following is the initial treatment for internal resorption? A. Pulpectomy. B. Pulpotomy. C. Pulp capping. D. Apicoectomy. Answer: A Although the process of internal resorption is frequently intermittent, repair may follow resorption. Clinicians should be aware that, once internal resorption is visible on radiographs or can be seen as a pink area through the intact enamel, it is considered a form of irreversible pulpitis. Radiographic evidence of internal resorption requires root canal therapy to stop the process. StertyWem T o p
26. The proposed mechanism by which a calcium hydroxide preparation initiates secondary dentin formation in direct pulp
cappings is by A. releasing calcium ions. B. stimulating differentiated ameloblasts to lay down dentin. C. stimulating fibroblasts to elaborate nuclei of the first order. D. stimulating undifferentiated cells of the tissue to differentiate into odontoblasts Answer: D When performing a direct pulp capping, calcium hydroxide produces coagulation necrosis at the contact surface of the pulp. The underlying tissue (undifferentiated cells) then differentiates into odontoblasts, which elaborate a matrix in about 4 weeks. This results in the formation of a reparative dentin bridge, caused by the irritating quality of the highly alkaline calcium hydroxide, which has a pH of 11 to 12. 27. Having just completed endodontic treatment on a maxillary central incisor, you are preparing the canal for a post when you inadvertently perforate the labial surface of the root. You would A. extract the tooth. B. cement the post using zinc-oxyphosphate cement. C. cement the post, then raise a flap and seal the defect surgically with amalgam. D. re-prepare the canal so the post is now totally within the canal and cement the post. Answer: C When performing post preparation for an upper anterior tooth, if a perforation happens on the labial surface of the tooth, it can be repaired by surgically intervention. But if a perforation happens on the palatal surface of the tooth, usually the tooth needs to be extracted. 28. Apicoectomy is CONTRAINDICATED when A. periodontal disease causes inadequate bony support. B. there is a granuloma at the apex of the tooth. C. more than one tooth is involved. D. the cortical plate is more than 4mm thick. E. the patient is diabetic. Answer: A Apicoectomy will further weaken a tooth with inadequate bony support. Apicoectomy should be performed on a restorable tooth with enough periodontal support.
29. In root resection (apicoectomy) it is considered good technique to A. remove as little of the root as possible. B. curet the soft tissue lesion in its entirety. C. be certain the apex is sealed. D. All of the above. Answer: D When performing an Apicoectomy, the soft tissue lesion should be removed completely and the root apex be removed as little as possible. The root apex should be sealed properly. 30. A retrograde filling is indicated A. when the apical foramen cannot be sealed by conventional endodontics. B. when a root perforation needs to be sealed. C. when conventional endodontics is impractical. D. All of the above. Answer: D The indication of retrograde filling include: (1) Apical granuloma refractory to conservative treatment (2) Conventional treatment ineffective (3) Treatment of failure cases after conservative treatment of teeth with apical periodontitis (4) Post or broken file in the canal (5) Root oerforation (6) External root resorption 31. Which of the following has the POOREST prognosis? A. Horizontal fracture in the apical one-third of the root. B. Horizontal fracture in the mid-root. C. Horizontal fracture 1-2mm subgingivally. D. Vertical root fracture. Answer: D Compared with horizontal root fracture, vertical root fracture has the poorest prognosis. In most cases of VRF in anterior teeth, extraction is the only available treatment option. 32. For composite resin preparations, cavosurface enamel margins are bevelled because 1. a bevelled margin produces a more favorable surface for etching. 2. a bevelled margin improves the edge strength of the composite resin. 3. after etching, the bonding agent reduces microleakage. 4. the procedure eliminates the need to polish the restoration. A. (1) (2) (3)
B. (1) and (3) C. (2) and (4) D. (4) only E. All of the above. Answer: B When performing a composite resin cavity preparation, the enamel margin should be beveled in order to improve aesthetics and expose the ends of the enamel rods for acid attack and then decrease the microleakage. 33. Retention of a gold inlay is improved by 1. addition of an occlusal dovetail. 2. increasing the parallelism of walls. 3. lengthening the axial walls. 4. placing a gingival bevel. A. (1) (2) (3) B. (1) and (3) C. (2) and (4) D. (4) only E. All of the above. Answer: A The retention of a cast restorations (inlay, onlay, crown, etc) of a tooth can be improved by increase the height of axial walls, increase the parallelism of walls, add occlusal dovetail. 34. When using ultra high speed cutting instruments for cavity preparation, the heat generated is directly related to the 1. duration of cutting. 2. size, speed and sharpness of the bur. 3. use of air and water spray. 4. existing pulp pathology. A. (1) (2) (3) B. (1) and (3) C. (2) and (4) D. (4) only E. All of the above. Answer: A Frictional heat is produced whenever a rotary bur or stone contacts tooth structure. The amount of heat produce during cutting is determined by the sharpness of the bur, the amount of pressure exerted on the bur or stone, and the length of time the cutting instrument contacts tooth structure. The safest way to prepare
tooth structure is to use ultra-high speeds of rotation with an efficient water cooling system, light pressure and intermittent cutting. 35. Which of the following instruments can be used for placing gingival bevels on inlay preparations? 1. Margin trimmers. 2. Enamel hatchets. 3. Carbide finishing burs. 4. Small diamond disks. A. (1) (2) (3) B. (1) and (3) C. (2) and (4) D. (4) only E. All of the above. Answer: B The gingival margin trimmer is designed to produce a proper bevel on gingival enamel margins of proximoocclusal preparations. It is similar in design to the enamel hatchet, except the blade is curved (similar to a spoon excavator), and the primary cutting edge is at an angle (other than perpendicular) to the axis of the blade. It is made as right and left types. Gingival bevels can also be placed by using a carbide finishing bur. StertyWem T o p
36. In restoring occlusal anatomy, the protrusive condylar path inclination has its primary influence on the morphology of A. cusp height. B. anterior teeth only. C. mesial inclines of maxillary cusps and distal inclines of mandibular cusps. D. mesial inclines of mandibular cusps and distal inclines of maxillary cusps. Answer: D The inclination of the condyle path is the factor that can be recorded from the patient. It is registered using protrusive registration. Patient is instructed to protrude the mandible with the occlusal rims. Inter-occlusal record material is injected between the occlusal rims in this position. Then the occlusal rim with the record
is transferred to the articular. This influence the shape of the posterior teeth. During protrusive movement, the mesial inclines of mandibular cusps contact the distal inclines of maxillary cusps. If the incisal guidance is steep, steep occlusal plane is needed to produce balanced occlusion. 37. Which of the following statements are true concerning the adult mandible? (1) The mandibular foramen lies in the centre of the mandibular ramus both in the vertical and horizontal planes. (2) The angle formed by the junction of the ramus and the body of the mandible is an acute one. (3) The genial tubercles are attachments for the anterior bellies of the digastric muscles. (4) The temporalis muscle attaches to the lateral surface of the coronoid process. A. (1) and (2) B. (1) and (4) C. (1) and (3) D. (1) (3) (4) Answer: B (1) The mandibular foramen is located below the occlusal plane at the age of 3. It subsequently moved upward with age. By the age of 9 to 10, it reaches approximately the same level as the occlusal plane. The foramen continued to move upward to 4-5mm above the occlusal plane in the adult. And the position of mandibular foramen in adult is about halfway between the anterior and posterior border of the ramus. (2) The mandibular angle is the angle formed by junction of the posterior edge of the ramus of the mandible and the inferior surfaces of the body of the mandible. At birth, the angle is obtuse (175°), and the condyloid portion is nearly in line with the body. In the adult, the mandibular ramus is almost vertical in direction, the mandibular angle normally is from 110° to 120°. (3) The anterior belly of the digastric muscle arises from a depression on the inner side of the lower border of the mandible called the Digastric Fossa, close to the symphysis and passes downward and backward and is attached to the hyoid bone. (4) Temporalis muscle origins from the temporal fossa of the temporal bone, passes medial to the zygomatic arch and inserts into the coronoid process of the mandible. Contraction of the Temporalis muscle elevates and retracts mandible.
38. A lingual approach for a conservative Class III preparation for a composite resin requires A. a retentive internal form. B. parallelism of the incisal and gingival walls. C. maintenance of the incisal contact area. D. All of the above Answer: D Idea conservative Class III composite resin cavity preparation: (1) Gingival margin: 1mm above gingival, incisal margin: just below proximal contact (maintenance of the incisal contact area), facial margin: parallel to facial surface, at junction of facial and middle 1/3 (2) Incisal and gingival walls parallel to each other with ideal depth of 1-1.25mm (incisal wall: 1.25mm, gingival wall: 1.0mm) (3) Internal line angle: Round with approximately 90 degree 39. Sterilization of carious dentin without pulp injury is assured by the application of A. phenol. B. 70% ethyl alcohol. C. chlorhexidine. D. absolute alcohol. E. None of the above. Answer: E Anti-bacterial agents, such as silver nitrate, phenol with and without camphor, chlorhexidine and eugnol have been used in an attempt to “sterilize” dentin after cavity preparations. However, their effectiveness as dentin sterilizers is questionable and their cytotoxicity can cause inflammatory changes in the underlying dental pulp. Other irritating agents include alcohol, chlotofrom, hydrogen peroxide. They may also cause inflammatory change of the pulp. 40. The cell of the dental pulp most capable of transforming into other cells is the A. fibroblast. B. undifferentiated mesenchymal cell. C. odontoblast. D. histiocyte Answer: B Dental pulp is a loose connective tissue, and it contains: (1) Cells:
fibroblasts and undifferentiated mesenchymal cells as well as other cell types (macrophages, lymphocytes, etc.) (2) Fibrous matrix (3) Ground substance. The large number of undifferentiated mesenchymal cells facilitates the recruitment of newly differentiating cells to replace others when they are lost – specifically the odontoblasts.
1. Following trauma, bluish-grey discolouration of the crown is due to: A. external resorption B. pulpal hemorrhage C. discoloured composite restoration D. chromogenic bacteria 2. Which of the following is least likely to cause pain? A. Carious pulp exposure B. Chronic hyperplastic pulpitis (pulp polyp) C. Acute pulpitis D. Apical periodontitis 3. A patient experiences pain and some gingival swelling in the anterior segment of the mandible. The mandibular lateral incisor has a shallow restoration, is tender to percussion and gives a positive response to the electric pulp tester. There is some mobility. The most likely diagnosis is: A. Acute apical abscess B. Acute serous pulpitis C. Lateral periodontal pulpitis D. Acute suppurative pulpitis E. Chronic ulcerative pulpitis 4. Which one of the following statements is true as defined in endodontics? A. Overfilling refers to the incomplete filling of the canal system with a surplus of material extruding beyond the apical foramen B. Underfilling refers to the complete filling of the canal space, but leaving voids in the pulp chamber for possible recontamination or infection C. Overextension refers to the extrusion of filling material through
an accessory canal D. Underextension refers to the vertical extent of the filling material regardless of its completeness of obturation E. All of the above 5. After completion of endodontic chemomechnical debridement you can expect to have: (1) removal all tissue from the entire root canal system (2) machined the canals to a microscopically smooth channel (3) caused some temporary inflammation (4) sterilized the root canal (5) Left some areas of the root canal system incompletely cleaned A. (1) (2) (3) B. (1) (3) C. (2) (4) D. All of the above (I do not know the answer) 6. Which of the following methods of instrument sterilization uses the lowest temperature? A. Steam autoclave B. Dry heat oven C. Glass bead sterilizer D. Alcohol autoclave 7. When root canals are treated topically with antibiotics rather than with disinfectants (1) a greater success rate results (2) the same rules of mechanical preparation and filling must be observed (3) treatment may be completed in fewer appointments (4) there is greater assurance that all microorganisms are destroyed (5) There is a danger of sensitizing patients to antibiotics A. (1) (3) (4) B. (2) (4) (5) C. (1) (2) (3) D. (2) (5) E. All of the above 8. The antibiotic of choice for infections of pulpal origin is: A. penicillin V B. lincomycin
C. erythromycin D. tetracycline 9. Endodontic therapy is CONTRAINDICATED in teeth with A. inadequate periodontal support B. pulp stone C. constricted root canals D. accessory canals E. curved roots 10. Periapical surgery is CONTRAINDICATED for a tooth that has a A. large perapical rarefacation B. fistula related to a periapical lesion C. vertical root fracture D. fracture of the root apex and a necrotic pulp E. a post and core retained crown 11. A patient telephones and tells you he has just knocked out his front tooth but that it is still intact. Your instruction should be to A. put the tooth in water and come to your office at the end of the day B. wrap the tooth in tissue and come to your office in a week's time C. put the tooth in alcohol and come to your office immediately D. place tooth under the tongue and come to your office immediately E. place the tooth in milk and come to your office immediately 12. The placement of a retentive pin in the proximal regions of posterior teeth would MOST likely result in periodontal ligament perforation in the A. mesial of a mandibular first premolar B. distal of a mandibular first premolar C. distal of a mandibular first molar D. mesial of a mandibular first molar 13. For a cast gold restoration, a gingival bevel is used instead of a shoulder because a bevel (1) protects the enamel (2) increases retention (3) improves marginal adaptation (4) increases the thickness of gold A. (1) (2) (3)
B. (1) and (3) C. (2) and (4) D. (4) only E. All of the above 14. In permanent teeth, two pulp canals are most commonly found in the A. distobuccal root of maxillary molars B. distal root of mandibular first molars C. palatal root of maxillary first premolars D. mesial root of mandibular first molars 15. Firm contact between approximating teeth is important because it A. locates the marginal ridges of each tooth B. keeps the teeth from having any movement during function C. insures proper cusp form and increases masticatory effciency D. stabilizes the dental arches and gives protection to the gingival papillae 16. In determining the ideal proximal outline form for a Class II amalgam cavity perparation in a molar the (1) axial wall should be 1.5mm deep (2) gingival cavosurface margin must be clear contact with the adjacent tooth (3) proximal walls diverage occlusally (4) facial and lingual proximal cavosurface margins must just clear contact with the adjacent tooth A. (1) (2) (3) B. (1) (3) C. (2) (4) D. All of the above 17. A rubber should be used in A. pulp capping procedures B. Amalgam placement C. composite placement D, removing carious dentin from deep lesions E. All of the above 18. The air-water spray used as a coolant in high speed cutting of a cavity will:
(1) decrease pulp damage (2) reduce fructional heat (3) keep the operating site clean (4) reduce clogging of cutting instruments A. (1) (2) (3) B. (1) (3) C. (2) (4) D. All of the above 19. Which of the following may affect the results of electric pulp testing? A. Emotional facrtors B. Pain threshold C. Analgesics D. Recent trauma E. All of the above 20. Which of the following statements is/are true? (1) Radiographs cannot differentiate between infected and noninfected periapical lesions (2) A definitive diagnosis of an apical lesion cannot be made on radiography alone (3) Perapical radiolucencies are not always indicative of loss of pulp vitality (4) A perapical radiograph can be used to locate the buccal bone level A. (1) (2) (3) B. (1) (3) C. (2) (4) D. All of the above 21. A positive and prolonged reactions to a heat stimulus indicates that the pulp is A. necrotic B. in an early hyperemic state C. normal D. irreversibly damaged 22. Which of the following is/are associated with the presence of microorganisms in the bloodstream? A. Anachoresis B. Cavernous sinus thrombosis
C. Bacteremia D. All of the above 23.Which of the following is/are true regarding a tooth filled with a formaldehyde-containing paste? A. Formaldehyde-containing pastes remain non-approved B. The drug manufacturer may be liable, along with the dentist C. formaldehyde-containing pastes have a high antigenic potential D. There are cases on record of parasthesia following overextrusion of such a paste in the vicinity of the mandibular nerve E. All of the above 24. The desired termination point of apical root canal preparation when performing endodontic treatment on a vital tooth is: A. 0.5 to 1.0mm short of the radiographic apex B. 3 mm short of the radiographic apex C. slightly through the apical foramen D. to the point where the patient feels sensation 25. Which of the following is the initial treatment for internal resorption? A. Pulpectomy B. Pulpotomy C. Pulp capping D. Apicoectomy 26. The proposed mechanism by which a calcium hydroxide preparation initiates secondary dentin formation in direct pulp capping is by: A. releasing calcium ions B. stimulating differentiated ameloblasts to lay down dentin C. stimulating fibroblasts to elaborate nuclei of the first order D. stimulating undifferentiated cells of the tissue to differentiate into odontoblasts 27. Having just completed endodontic treatment on a maxillary central incisor, you are preparing the canal for a post when you inadvertently perforate the labial surface of the root. You would A. extract the tooth B. cement the post using zinc-oxyphosphate cement C. cement the post, then raise a flap and seal the defect surgically with amalgam
D. re-prepare the canal so the post is now totally within the canal and cement the post 28. Apicoectomy is CONTRAINDICATED when A. periodontal disease causes inadequate bony support B. there is a granuloma at the apex of the tooth C. more than one tooth is involved D. the cortical plate is more than 4mm thick E. the patient is diabetic 29. In root resection (apicoectomy) it is considered good technique to A. remove as little of the root as possible B. curet the soft tissue lesion in its entirety C. be certain the apex is sealed D. All of the above 30. A retrograde filling is indicated A. When the apical foramen cannot be sealed by conventional endodontics B. When a root perforation needs to be sealed C. when conventional endodontic is impractical D. All of the above 31. Which of the following has the poorest progonosis? A. Horizontal fracture in the apical one-third of the root B. Horizontal fracture in the mid-root C. Horizontal fracture 1-2mm suggingivally D. Vertical root fracture 32. For composite resin preparation, cavosurface enamel margins are beveled because (1) a beveled margin produces a more favorable surface for etching (2) a beveled margin improves the edge strength of the composite resin (3) after etching, the bonding agent reduces microleakage (4) the procedure eliminates the need to polish the restoration A. (1) (2) (3) B. (1) (3) C. (2) (4) D. All of the above
33. Retention of a gold inlay is improved by: (1) addition an occlusal dovetail (2) increasing the parallelism of walls (3) lengthening the axial wall (4) placing a gingival bevel A. (1) (2) (3) B. (1) (3) C. (2) (4) D. All of the above 34. When using ultra high speed cutting instruments for cavity preparation, the heat generated is directly related to the: (1) duration of cutting (2) size, speed and sharpness of te bur (3) use of air and water spray (4) existing pulp pathology A. (1) (2) (3) B. (1) (3) C. (2) (4) D. All of the above 35. Which of the following instruments can be used for placing gingival bevels on inlay preparation? (1) Margin trimmer (2) Enamel hatchets (3) Carbide finishing burs (4) Small diamond disks A. (1) (2) (3) B. (1) (3) C. (2) (4) D. All of the above 36. In restoring occlusal anatomy, the protrusive condyle path inclination has its primary influence on the morphology of: A. cusp height B. anterior teeth only C. mesial inclines of maxillary cusps and distal inclines of mandibular cusps D. mesial inclines of mandibular cusps and distal inclines of maxillary cusps 37. Which of the following statements are true concerning the adult
mandible? (1) The mandibular foramen lies in the centre of the mandibular ramus both in the vertical and horizontal planes (2) The angle formed by the junction of the ramus and the body mandible is an acute one (3) The genial tubercles are attachments for the anterior bellies of the digastric muscle (4) The temporalis muscle attaches to the lateral surface of the coronoid process A. (1) and (2) B. (1) and (4) C. (1) and (3) D. (1) (3) (4) 38. A lingual approach for a conservative class III preparation for a composite resin requires A. a retentive internal form B. parallelism of the incisal and gingival walls C. maintenance of the incisal contact area D. All of the above 39. Sterilization of carious dentin without pulp injury is assured by the application of A. phenol B. 70% ethyl alcohol C. chlorhexidine D. absolute alcohol E. None of the above 40. The cell of the dental pulp most capable of transforming into other cells is the: A. fobroblast B. undifferentiated mesenchymal cell C. odontoblast D. histiocyte 49. Which of the following is the most probable postoperative complication of intracoronal bleaching a tooth that has not been adequately obturated? A. Fracture B. Discoloration C. Retrograde pulpitis
D. Acute apical periodontitis E. External cervical root resorption 50. Which of the following are true statements about incision and drainage of an acute apical abscess (1) A rubber dam drain may be placed and sutured to assist drainage (2) The procedure is any indicated with a localized, fluctuant swelling (3) Profound anesthesia of the surgical site is not always possible (4) Relief of the pressure and pain is immediate after treatment A. (1) (2) (3) B. (1) (3) C. (2) (4) D. All of the above 51. In the mandibular firs premolar, the occlusal dovetail of an ideal disto-occlusal amalgam preparation is usually not extended into mesial fosa beause of the: A. mall lingual lobe B. large buccal cusp C. large buccal pulp horn D. prominent transverse rige 52. When removal of carious dentin results in an exposure of nonvital pulp, treatment of choice is: A. institute endodontic treatment B. cap the exposed pulp horn with calcium hydroxide C. occlude the cavity with a light packing of cotton moistened with eugenol D. place a temporary restoration and observe 53. In the restoration of a tooth, cavity vanish reduces: A. ion migration from amalgam to tooth B. transfer of thermal changes C. amalgam corrosion D. galvanic stimulation of the pulp 54. The initial treatment of choice for a 16 year old patient, who presents with multiple extensive carious lesions, is to place the patient on a preventive regime and to A. place amalgam restorations over the next few months
B. excavate caries and place temporary restorations within the next few weeks C. delay any treatment until the hygiene improves D. restore all teeth with composite resin over the next few months 55. During cavity preparation under rubber dam, a small mechanical exposure occurs. The correct procedure is to: A. swab the exposure with eugenol B. place calcium hydroxide over the exposure C. perform a pulpotomy D. perform a pulpectomy 56. A protective mechanism of the dental pulp to external irritation or caries is the formation of A. pulp stones B. secondary dentin C. secondary cementum D. primary dentin 57. The joining together of two teeth in the root portion through cemented union is known as: A. germination B. fusion C. twinning D. concrescense 58. Fractured incisal angles in the permanent teeth of adolescent patients are best restored using A. stainless steel crowns. B. gold castings. C. full coverage restorations. D. acid etch composite resin techniques 59. When odontoblasts are destroyed or undergo degeneration, they are replaced by A. ameloblasts. B. undifferentiated mesenchymal cells. C. multinucleated giant cells. D. osteoblasts. 60. In an 80-year old patient you would expect A. a reduced size of the pulp chamber.
B. increased incidence of pulp stones. C. increased tendency to pulpal fibrosis. D. All of the above. 61. In teeth with complete pulp necrosis, the periapical area is involved if 1. there is pain to thermal stimuli. 2. there is pain on percussion. 3. the tooth throbs when the patient is lying down. 4. the radiograph shows an apical radiolucency. A. (1) (2) (3) B. (1) and (3) C. (2) and (4) D. (4) only E. All of the above. 62. The prognosis for an avulsed tooth is principally affected by A. length of time the tooth was out of the mouth. B. condition of the socket when the tooth was replanted. C. removal of necrotic cementum. D. pulp extirpation. 63. Radiographs of the mandibular incisor teeth of a 45 year old healthy black female patient reveal periapical radiolucencies. The teeth are vital and asymptomatic. You would A. perform a biopsy of the radiolucent lesion. B. perform endodontic therapy on the four incisors. C. place a drain in the affected area. D. observe periodically. 64. Which of the following could be immediate postoperative complications of periapical surgery? 1. Haemorrhage. 2. Edema. 3. Paresthesia. 4. Pain. 5. Mucocele. A. (1) (2) (3) B. (1) (2) (3) (4) C. (1) (3) (5) D. All of the above.
65. The muscle primarily responsible for moving the mandible to a lateral position is the A. masseter. B. lateral (external) pterygoid. C. medial (internal) pterygoid. D. buccinator. E. temporalis. 66. Which of the following muscles comprise the retromolar pad? 1. Lateral (external) pterygoid. 2. Buccinator. 3. Palatoglossus. 4. Superior constrictor. A. (1) (2) (3) B. (1) and (3) C. (2) and (4) D. (4) only E. All of the above. 67. Profile features of extreme overjet, recessive chin and deep labial mento-labial sulcus in the chin are referred to as A. prognathic relationship. B. mesognathic relationship. C. retrognathic relationship. D. crossbite relationship. 68. Which of the following are characteristic symptoms of acute suppurative pulpitis? 1. Spontaneous throbbing pain. 2. Prolonged pain initiated by heat. 3. Increased pain while lying down. 4. Increased pain by cold. A. (1) (2) (3) B. (1) and (3) C. (2) and (4) D. (4) only E. All of the above. 69. Histologically, a pulp polyp consists of 1. a mass of collagenous fibres. 2. Russell bodies. 3. proliferating capillaries.
4. fibroblasts. 5. polymorphonuclear leucocytes. A. (1) (2) (3) (4) B. (1) (3) (4) C. (1) (3) (4) (5) D. (2) and (5) E. All of the above. 70. Which of the following conditions is most likely to be associated with a draining fistula? A. Chronic periapical periodontitis. B. Reversible pulpitis. C. Hypercementosis. D. Traumatic bone cyst
