Case History and Clinical Examination in orthodontics
Presented by : Dr. Rajesh Gyawali (
[email protected]) (
[email protected]) Resident, Department of Orthodontics and Dentofacial Orthopaedics Faculty of Dentistry, Institute of Medicine, Kathmandu Guided by : Dr. Basant Kumar Shrestha Associate Prof. and Head Department of Orthodontics and Dentofacial Orthopaedics Faculty of Dentistry, Institute of Medicine, Kathmandu
Case History Case History is the information gathered from the patient or parent or guardian to aid in overall diagnosis of the case. It includes personal details, chief complaint, past and present medical and dental history and 1
any associated family history. The aim is to establish a rapport with the patient and to obtain information about individual’s complaint. 1. Personal details A. Name The The patie atient nt’s ’s name ame sho should be reco ecorded ded for for the the purpo urpose se of communication and identification. Addressing a patient by his or her name name has a benefi beneficial cial psycho psycholog logica icall effect effect.. It makes makes the patien patientt more comfortable and arouses a feeling of familiarity. B. Age The age of the patient helps in diagnosis, treatment planning and growth prediction. There are certain transient conditions that occur during development are considered normal for that age. In addition, there there are certai certain n treat treatmen mentt modali modalitie ties s that that are best best carrie carried d out during growing age, like- growth modification using functional and ortho orthoped pedic ic applia appliance nces. s. Surgic Surgical al correc correctiv tive e proced procedur ures es are best best carried out after the cessation of the growth. C. Sex The patient’s sex also helps in treatment planning. The timing of growth related events including growth spurts, eruption of teeth and onset of puberty are different in males and females. Psychological reaction of males and females may be different towards the same malocclusion. Females are more concerned about facial esthetics. D. Address and contact number It helps in future correspondence and managing the appointments. Patients coming from far may require a different appliance therapy as they might not be able to visit the clinic frequently. E. Occupation It helps in evaluation of the socio-economic status of the patient and helps in the selection of the appropriate appliance. F. Religion G. Ethnic origin
1. Chief Complaint The patient’s chief complaint should be recorded in his or her own words. words. There There are three three logical logical reaso reasons ns for patient patient concer concern n about about the alignment and occlusion of the teeth: impaired dentofacial esthetics that can lead to psychosocial psychosocial problems; problems; impaired impaired function; function; and a desire desire to improve improve dentofacial dentofacial esthetics. esthetics. It is important important to establish establish their relative
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importance to the patient and their desires. The parents’ perception of the malocclusion should be noted. A seri series es of lead leadin ing g ques questi tion ons, s, begi beginn nnin ing g with with,, "Tel "Telll me what what bothers you about your face or your teeth," may be necessary to clarify what is important to the patient. The orthodontist may or may not agree with the patient’s assessment – the judgement comes later. But, at this stage, it is necessary to find out what is important to the patient. Thi This s will will help help in sett settin ing g trea treatm tmen entt obje object ctiv ives es and and sati satisf sfyi ying ng the the patient and or parents in general. 2. Medical History Knowledge of the patient’s general health is essential and should be obtain ained prior to the exami amination. It is best obtained by questionnaire. In most of the cases, orthodontic treatment can be undertaken but precautions should be taken prior to surgical procedures. Patients with rheu rheuma mati tic c feve fever, r, cardi cardiac ac anom anomal alie ies, s, epil epilep epsy sy,, diab diabet etes es and and bloo blood d dyscrasias may require special precautions. The medical history should include information on drug usage. The use use of cert certai ain n drug drugs s like like aspi aspiri rin n (pro (prost stag agla land ndin in inhi inhibi bito tors rs)) or bone bone resorption inhibiting agents may impede orthodontic tooth movement. Patients who are suffering from acute, debilitating conditions such as viral fever should be allowed to recover prior to initiating orthodontic treatment. History of trauma should be noted. Trauma to the jaws or teeth is often overlooked in child with other trauma, so a jaw injury may not have been diagnosed at that time. This is significant as it affects the future development of jaws and teeth. 3. Dental History The patient’s dental history should include information on the age of eruption and exfoliation of deciduous and permanent teeth, history of extraction, decay, restorations and trauma. The past dental history will also help in assessing the patients and parents’ attitude towards dental health. 4. History of Habits History of abnormal habits like finger, digit sucking, nail biting, lip biting grinding, clenching, and mouth breathing should be taken as they influence the development of dentoalveolar structures. 5. Pre-natal History Pre-natal history should include information on the condition of the mother during pregnancy and the type of delivery. Forceps deliveries have been associated with injury to the temporomandibular joint (TMJ) and may cause ankylosis and mandibular growth retardation. Nutrition status and infections during pregnancy should also be noted. 6. Post-natal History 3
It should include information on type of feeding, presence of habits and milestones of normal development. 7. Family History Many Many malocc malocclus lusion ions s like like skelet skeletal al Class Class II and Class Class III, III, crowdi crowding, ng, spacing overjet, high frenal attachments and congenital conditions like cleft lip and palate are inherited. 8. Physical Growth evaluation The parents should be questioned about the child’s growth status. (eg: Has your child had any recent rapid growth ?). Rapid growth during the adoles adolescen centt growt growth h spurt spurt facili facilitat tates es tooth tooth moveme movement nt but growt growth h modification may not be possible in a child who is beyond the peak of the growth spurt. For children approaching puberty, questions about how rapidly the child has grown recently, whether clothes sizes have changed, whether ther there e are are sign signs s of sexu sexual al matu matura rati tion on,, and and when when sexu sexual al matu matura rati tion on occur occurred red in older older siblin siblings gs usuall usually y provi provide de the necess necessary ary infor informat mation ion about where the child is on the growth curve. In orthodontic clinic, measuring the height and weight regularly and calculation of bone age from vertebrae as seen in the cephalometric radiograph radiograph can be helpful. helpful. Serial Serial cephalomet cephalometric ric radiograp radiographs hs offer the most most accu accura rate te way way to dete determ rmin ine e whet whethe herr grow growth th has has stop stoppe ped d or is continuing. 9. Social and Behavioral Evaluation It should explore – patient’s motivation for treatment, what he or she expects as a result of treatment and how co-operative or uncooperative the patient is. Motivation can be external or internal. External motivation is that suppli supplied ed by pressu pressure re from from anothe anotherr indivi individua dual, l, like child child broug brought ht for treatment by mother; older patient by his girlfriend. Internal motivation come comes s from from with within in the the indi indivi vidu dual al and and is base based d upon upon his his or her her own own assessment of the situation and desire for the treatment. What What pati patien entt expe expect cts s from from the the treat treatme ment nt shou should ld be expl explor ored ed carefully especially in case of patients with primarily cosmetic problems.
Clinical Examination
1. General Examination Each patient should be regarded as a whole person rather than as a 'pair of jaws'. The examination, therefore, begins immediately the patient ente enters rs the the clin clinic ic.. If poss possib ible le,, both both pare parent nts s shou should ld be pres presen entt at the the exam examin inat atio ion; n; this this affo afford rds s an oppo opport rtun unit ity y to obse observ rve e any any here heredi dita tary ry character characters s which may be present, present, and also an opportuni opportunity ty to discuss discuss the medical history, diagnosis and treatment.
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A. Height and weight It gives a clue to the physical growth and maturation of the patient. The growth of the body in general is related to the growth of the jaws and face particularly. B. Gait Gait is the way a person walks. Abnormalities of gait are usually associated with neuromuscular disorders. C. Built Sheldon classified body built into: i. Ectomo Ectomorp rphic hic : Tall Tall and thin thin physiq physique ue ii. Mesomorphic : Average physique iii. Endomorphic : Short and obese physique
1. Extra-oral Examination A. Shape of Head The shape of head can be evaluated based on the cephalic index which is based on the anthropometric determination of the maximum width and maximum length of the head. It is given by MartCephaic in aindex nd Saller as: Maximum skull width Ma ximum skull length • • • •
Mesocephalic : I = 76.0 -80.9 Brchycephalic : I = 81.0- 85.4 Broad and short head Dolicocephalic : I < 75.9 Long and narrow head Hyperbrachycephalic : I > 85.5
A. Shape of the face The shape of the face is assessed by morphologic facial index which was given by Martin and Saller(1957) as: Facial Facial Index Index Morpholo Morphologic gic facial height height (Distance (Distance between between nasion and gnathion) Bizygomatic width (Distance between the two zygoma points) • •
•
•
•
Hypereuryprosopic Hypereuryprosopic : I < 78.9 Euryprosopic Euryprosopic : I = 79.0 – 83.0 – Broad and short facial form Mesopros Mesoprosopic opic : I = 84.0 – 87.9 – Average Average or normal normal facial form Letoprosopic : I = 88.0 – 92.9 – Long and narrow facial form Hyperleptoprosopic Hyperleptoprosopic : I > 93.0 5
A. Assessment of facial symmetry A certain degree of asymmetry between right and left sides of the face is seen in most of the individuals. The face should be exam examin ined ed in the the tran transv sver erse se and and vert vertic ical al plan planes es to dete determ rmin ine e a greater degree of asymmetry than the normal. Gross facial asymmetries may be seen in patients with• Hemifacial atropy/hypertrophy atropy/hypertrophy • Congenital defects • Unilateral condylar hyperplasia • Unilateral Ankylosis A. Facial profile The profile is examined from the side by making the patient view at a distant object, with the FH plane parallel to the floor. The profile is assessed by the two reference linesA line joining the forehead and the soft tissue point A (deepest point in the curvature of upper lip) A line line join joinin ing g poin pointt A and and the the soft soft tiss tissue ue pogo pogoni nion on (mos (mostt anterior point of the chin) Base Based d on the the rela relati tion onsh ship ip betw betwee een n thes these e two two line lines, s, thre three e types of profile existsStraight : The two two lines form form a nearly straight line Conv Co nvex ex : The The two two line lines s form form an angle angle with with the conca concavi vity ty facing the tissue. It occurs in cases of prognathic maxilla or retrognathic mandible as seen in Class II Div I. Concave : The two reference lines form an angle with the convexity towards the tissue. This type of profile is seen in Class III patients. A. Facial divergence It is defined as an anterior or posterior inclination of the lower face relative to the forehead. Facial divergence is determined by a line drawn from forehead to the chin Anterior divergence : The line is inclined anteriorly . Posterior divergence : The line is inclined posteriorly. Straight or orthognathic : The line is perpendicular to the floor, no slanting. A. Assessment of antero-posterior jaw relationship The antero-posterior jaw relationship between the upper and lower jaw can be assessed to certain extent clinically by placing index and middle fingers at the approximate A and B points after lip retraction. Ideally the maxillary skeletal base is 2-3mm forward of the mandibular skeletal base when the teeth are in occlusion. In skeletal Class II patients, the index finger is anterior to the middle finger or the hands point upward. In skeletal Class III patients, the middle finger is anterior to the index finger or the hands points downwards. In skeletal Class I patients, the hand is at even level. 6
B. Assessment of vertical jaw relationship
Normally, the distance between glabella to subnasale is equal to the distance between the subnasale to the underside of the chin. Reduced lower facial height is associated with deep bite while the increased facial height is with anterior open bite. The vertical skeletal relationship can also be assessed by stud studyi ying ng the the angl angle e form formed ed betw betwee een n the the lowe lowerr bord border er of the the mandib mandible le and the Fra Frankf nkfor ortt horizo horizonta ntall plane. plane. Normal Normally, ly, the two planes intersect at the occipital region. In case the two planes meet beyo beyond nd the the occi occipi pita tall regi region on,, it indi indica cate tes s a low low angl angle e case case or hori horizo zont ntal al grow growin ing g face face.. If the the two two plan planes es meet meet ante anteri rior or to the the occipital region it indicates a high angle case or a vertical growing face. C. Evaluation of facial proportion
A well proportioned face is divided into three equal vertical thirds using four horizontal planes- at the level of the hair line, the supraorbital ridge, the base of the nose and the inferior border of chin. Within the lower face, the upper lip occupies one third of the distance. D. Lips Norm Normal ally ly,, the the uppe upperr lip lip cove covers rs the the enti entire re labi labial al surf surfac ace e of upper anteriors except the incisal 2-3mm. The lower lip covers the entire labial surface of of the lower anteriors anteriors and 2-3 mm of the incisal edges of the upper anteriors. Lips can be classified intoComp Co mpet eten ent: t: Slig Slight ht cont contac actt of lip lip when when the the musc muscul ulat atur ure e is relaxed. Incomp Incompete etent: nt: Anatom Anatomica ically lly short short lips lips which which do not not contac contactt when when muscul musculatu ature re is relaxe relaxed. d. Lip seal seal is achiev achieved ed only only be active contraction of the orbicularis oris and mentalis muscle. Potentially competent: Normal lips which fail to form the lip seal due to proclined proclined upper incisors. Everted lips: Hypertropied lips with weak muscular tonicity. tonicity. A. Nose
Size: Normally nose is one third of the total facial height. Contour: Shape can be straight, convex or crooked. Nostril: Normally they are oval and bilaterally symmetrical. symmetrical.
A. Nasolabial angle It is the angle formed between the lower border of the nose and a line joining the subnasale with the tip of the upper lip (labrale superius). The angle is normally 110 o. It is reduced in patients with proclined upper anteriors or prognathic maxilla.
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B. Chin
Chin Chin posi positi tion on and and prom promin inen ence: ce: Prom Promin inen entt chin chin is usua usuall lly y associated associated with Class Class III malocclusio malocclusion n while recessive recessive chins are common in Class II malocclusion. Mentolabial sulcus: It is the concavity present below the lower lip. Deep sulcus is seen in class II cases where as shallow sulcus is seen in bimaxillary protrusion. Mental Mentalis is activi activity: ty: Normal Normally, ly, the mental mentalis is muscle muscle does does not show any contractio contraction n at rest. rest. Hyperactive Hyperactive mentalis activity activity is seen in some malocclusion such as Class II division 1 cases. It causes puckering of the chin.
1. Intra-oral Examination A. Tongue Abnormalities of tongue can upset the muscle balance and equilibrium leading to malocclusion. Presence of excessively large tong tongue ue is indi indica cate ted d by the the pres presen ence ce of impr imprin ints ts of teet teeth h on the the lateral margins of the tongue giving a scalloped appearance. Short lin lingual gual frenum enum call called ed tong tongue ue tie tie lead leads s to impa impair ired ed ton tongue gue movement. B. Pala alate Palate is examined for the following findingsi. Vari Variat atio ions ns in pala palata tall dept depth h are are asso associ ciat ated ed with varia variati tion on of facial form. Brachycephalic patients have broad and shallow palates where as dolicocephalic patients have deep palates. ii. Prese Presence nce of swelli swelling ng indicate indicates s impact impacted ed tooth, tooth, cysts or bony pathology. iii. Mucosal Mucosal ulceration ulceration and indentatio indentations ns are feature feature of traumatic traumatic deep bite. iv. Presence Presence of clefts clefts v. The third third rugae rugae is usuall usually y in line line with the canine canine.. It helps to assess maxillary anteriors proclination. A. Gingiva The gingiva should be examined for inflammation, recession, muco mucogi ging ngiv ival al lesi lesion ons. s. Loca Locall ging gingiv ival al lesi lesion ons s may may occu occurr due due to occlusal trauma, abnormal functional loadings or medications (eg: Dilantin, Phenytoin). In mouth breathers, open lip posture causes dryness of the mouth leading to anterior marginal gingivitis. B. Frena Frenall atta attachm chment ents s The maxillary labial frenum can be thick, fibrous and have low attachment attachment.. Such attachments attachments prevent prevent the two maxillary central incisors from approximating each other leading to midline diastema.
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Mandib Mand ibul ular ar labi labial al fren frenum um if has has high high atta attach chme ment nt,, may may lead lead to recession of gingiva. Abnormal frenum attachments can be diagnosed by blanch test test(( when when the uppe upperr lip lip is stret stretch ched ed upwar upwards ds and outw outwar ards ds,, blanching in the region of the interdental papilla indicates abnormal frenum attachment). C. Tonsi Tonsils ls and and Adenoi Adenoids ds The The size size and and infl inflam amma mati tion on of tons tonsil il shou should ld be exam examin ined ed.. Abnorm Abnormall ally y inflam inflamed ed tonsil tonsils s cause cause altera alteratio tion n in tongue tongue and jaw post postur ure e ther thereb eby y upse upsett ttin ing g the the orooro-fa faci cial al bala balanc nce e lead leadin ing g to malocclusion. D. Dent Dentit itio ion n i. Status- the number of teeth present, unerupted or missing. ii.Presence of caries, restoration, malformation, hypoplasia, wear and discoloration. iii.Molar relation. iv.Overjet, overbite. v.Mi v.Midl dlin ine e of the the face face and and its its coin coinci cide denc nce e with with the the dent dental al midline. vi.Individual tooth irregularities like rotation, displacement, fracture. vii.Shape and symmetry of the upper and lower jaws.
1. Functional Examination Normal functioning of stomatognathic system promotes normal growth and development of oro-facial complex. Improper functioning can result in various malocclusions. Therefore, orthodontic diagnosis shou should ld not not be rest restri rict cted ed to stat static ic eval evalua uati tion on of teet teeth h and and thei theirr supporting structures but should include examination of the functional units of stomatognathic system. It is important to note in the beginning whether the patient has normal coordination and movements. If not, as in an individual with cere cerebr bral al pals palsy y or othe otherr type types s of gros gross s inco incoor ordi dina nati tion on,, norm normal al adaptation adaptation to the changes in tooth tooth position position produced by orthodon orthodontics tics may not occur, and the equilibrium effects may lead to post-treatment relapse. The functional examination should includeA. Assessment Assessment of postural postural rest rest position position and inter-occlusa inter-occlusall clearance clearance The postural rest position is the position of the mandible at whic which h the the musc muscle les s that that clos close e the the mand mandib ible le and and that that open open the the mandible are in the state of minimal contraction. At rest position, a space space exis exists ts betw betwee een n the the uppe upperr and and lowe lowerr jaws jaws whic which h is call called ed interocclusal clearance or freeway space which is normally 3mm in canine region. 9
The The post postur ural al rest rest posi positi tion on shou should ld be dete determ rmin ined ed with with the the patient relaxed and seated upright with back unsupported. The head is oriented by making the F_H plane parallel to the floor. Methods to record the postural head position arei. Phone honeti tic c meth ethod: The pati patien entt is told told to pronoun nounce ce som some conson consonant ants s like like “M” or words words like like “Miss “Mississ issipp ippi” i” repeat repeatedl edly. y. The mandible returns to the postural rest position 1-2 seconds after the exercise. ii. Comman Command d method: method: The patient patient is asked asked to perfor perform m selected selected func functtion ions like like swal swallo low wing. ing. The The mand mandib ible le then then retu eturns spontaneously to rest position. iii. Non command command method: method: The patient patient is observed as he speaks speaks or swallo allows ws.. The pati patien entt is not not awar aware e that that he is bein being g examined. While talking, the patient’s musculature is relaxed and the mandible reverts to the postural rest position. B. Evaluation Evaluation of path of closu closure re The path of closure is the movement of mandible from rest position to habitual occlusion. Abnormalities of path of closure are seen in some form of malocclusion. Forward path of closure: Many children and adults with a skeletal Clas Class s II rela relati tion onsh ship ip and and an unde underl rlyi ying ng sk skel elet etal al Clas Class s II jaw jaw relationship will position the mandible forward in a "Sunday bite," making making the occlus occlusion ion look look better better than it really really is. Someti Sometimes mes an apparent Class III relationship results from a forward shift to escape incisor incisor interferen interferences ces in what is really really an end-to-end end-to-end relationship relationship. These patients are said to have pseudo- Class III malocclusion. Backward path of closure: Class II division 2 cases exhibit premature incis incisor or cont contac actt due due to retr retroc ocli line ned d maxi maxill llar ary y inci inciso sors rs.. Thus Thus the the mandible is guided posteriorly to establish occlusion.
Latera rall devi deviat atio ion n of the the mand mandib ible le is Late Latera rall path path of clos closur ure: e: Late associated with occlusal prematurities and a narrow maxillary arch. C. Examin Examinati ation on of TMJ The functional examination of TMJ should include auscultation and palpation of the temporomandibular joint and the musculature associated with mandibular opening. The patient is examined for the symp sympto toms ms of TM TMJJ prob proble lems ms like like clic clicki king ng,, crep crepit itus us,, pain pain of the the masticato masticatory ry muscles, muscles, limitation limitation of jaw movement, movement, hyper mobility and morphological abnormalities. The maximum mouth opening is determined by measuring the distance between the maxillary and mandibular incisor edge with the mouth wide open. The normal inter incisal distance is 40-45 mm. D. Examinatio Examination n of oral oral functio functions ns 10
i. Respiration Humans exhibit three types of breathing- nasal, oral and oronasaal. There are some tests which helps to diagnose the mode of respirationa. Mirr Mirror or test: test: A doub double le sided sided mirr mirror or is held held betwee between n the the nose nose and mouth. Fogging on the nasal side of the mirror indicates nasal breathing while fogging towards the oral side indicates oral breathing. b. Cotton Cotton test: test: A butter butterfly fly shaped shaped piece piece of cotton cotton is placed placed over over the upper lip below the nostrils. If the cotton flutters down it indica indicates tes nasal nasal breath breathing ing.. It helps helps to determ determine ine unilat unilatera erall nasal blockage. c. Water Water test: test: The patien patientt is asked to fill fill the mouth mouth with with water water and retain it for a while. Nasal breathers do it easily while mouth breathers feel difficult. d. Obse Observ rvat atio ion: n: In nasa nasall brea breath ther ers, s, the the exte extern rnal al nare nares s dilat dilate e duri during ng insp inspir irat atio ion. n. In mout mouth h brea breath ther ers, s, ther there e is eith either er no change in the external nares or they may constrict during inspiration. i. Tongu ngue thr thrus usti ting ng ii. Speech Speech Speech proble problems ms can be relate related d to malocc malocclus lusion ion,, but normal speech is possible in the presence of severe anatomic dist distor orti tion ons. s. Spee Speech ch diff diffic icul ultie ties s in a chil child, d, ther theref efor ore, e, are are unlikely to be solved by orthodontic treatment. If a child has a speech problem and the type of malocclusion related to it, a combination of speech therapy and orthodontics may help. If the speech problem is not listed as related to malocclusion, orthodont orthodontic ic treatment may be valuable valuable in its own right right but is unlikely to have any impact on speech. Patients having tongue thrust habit tend to lisp while cleft palate patients may have a nasal tone. Speech Difficulties Related to Malocclusion: Speech Sound
Problem
/s/, /z/ (sibilants)
Lisp
/t/, /d/ Difficulty (linguoalveolar production stops) /f/, /v/ (labiodentals Distortion fricatives) Th, sh, chDistortion (linguodental 11
Related malocclusion Anterior open bite, large gap between incisors in Lingua Linguall positi position on of maxillary incisors Skeletal Class III Anterior open bite
fricatives [voiced or voiceless]) iii. iii. Swallo Swallowin wing g In a new born, the tongue is relatively large and protrudes between the gum pads and takes part in establishing the lip seal. This kind of swallow is called infantile swallow and is seen till 1.5 to 2 yrs of age. Infantile swallow is replaced by mature swallow as the buccal teeth erupt. The persistence of infantile swallow can be a cause of malocclusion. The persistence of infantile swallow is indicated by the presence ofProtrusion of the tip of the tongue. Contraction of perioral muscles during swallowing. No contact at the molar region during swallowing. iv. iv. Lip Lips
1. Evaluation of Facial and Dental Appearance A systematic examination of facial and dental appearance should be done in three steps: 1. The face face in all three three planes planes of space space (macro-e (macro-esthet sthetics) ics) 2. The smile framewor framework k (mini-es (mini-estheti thetics) cs) 3. The teeth teeth (micr (micro-e o-esth stheti etics) cs) 1. Facial Proportions: Macro Esthetics a. Assess Assessmen mentt of Developm Development ental al Age: The The asse assess ssm ment ent of devel evelop opme men ntal tal age is par arti ticu cula larrly important for children around the age of puberty when most of the orthodon orthodontic tic treatm treatment ent is carrie carried d out. out. The degree degree of physical development is much more important than chronological age in determining how much growth remains. b. Facial Facial Esthetic Esthetics s vs Facial Facial proporti proportion on Whether a face is considered beautiful or not is determined by ethinc and cultural factors, a disproportionate face becomes a psyc psycho hoso soci cial al prob proble lem. m. Dist Distor orte ted d and and asym asymme metr tric ic faci facial al features are a major contributor to facial esthetic problems; where as proportionate features are acceptable if not always beautiful. So the goal of the facial examination is to detect the facial disproportion. i. Frontal Examination A small degree of facial asymmetry exists in all normal individual. This normal symmetry should be distinguished from severe disproportion caused due to deviation of chin or nose to one side. Some of the measurements could be made on a ceph cephal alom omet etri ric c radi radiog ogra raph ph but but many many coul could d not. not. It is better better to make make measur measureme ements nts clinic clinicall ally y becaus because e soft soft 12
tissue tissue propor proportio tions ns as seen seen clinic clinicall ally y determ determine ine facial facial proportion. The distance from the hair line to base of the nose, base of the nose to bottom of nose and bottom of nose to chin should be same. Similarly, an ideal proportional face can be divide into central, medial and lateral equal fifths. The separation of the eyes and the width of the eyes which should be equal, determine the central and medial fifths. The nose and chin should be centred within the central fifth, with width of the nose the same as or slightly wider than the central fifth. The interpupillary distance should be equal the width of the mouth. Low set set eyes eyes or ear ars s that ar are e unus nusuall ually y far far apar artt (hypertelorism) may indicate either the presence of a syndrome or a microform of a craniofacial anomaly. If a synd syndro rome me is susp suspect ected ed,, hand hands s shou should ld be exam examin ined ed because there are a number of dental digital syndromes. ii.Profile Analysis Profi Profile le analys analysis is gives gives the same same infor informat mation ion though though in less detail for the underlying skeletal relationships, as obta obtain ined ed from from the the anal analys ysis is of late latera rall ceph cephal alom omet etri ric c radiographs. So, the technique of facial profile analysis is also called “Poor man’s cephalometric ce phalometric analysis”.
1) Asse Assess ssme ment nt of jaw posi positi tion on in ante antero ro-p -pos oste teri rior or plane of space It is examined by placing the patient in physiologic natural head position (FH plane is parallel to the ground und). The The pro profile file is asses ssesse sed d by the two two reference linesline joining the forehead and the soft tissue point A. line joining point A and the soft tissue pogonion. These two lines nearly form a straight line. A straight profile wheth ether it is anter eriiorly or posteriorly diverging doesn’t indicate a problem where as concavity or convexity does. 1) Evaluation Evaluation of of lip posture posture and incisor incisor promine prominence nce 2) Re-e Re-eva valu luat atio ion n of vert vertic ical al faci facial al prop propor orti tion ons, s, and and evaluation of mandibular plane angle The mandibular plane is visualized clinically by placing a finger or mirror handle along the lower border of the mandible. A steep mandib mandibula ularr plane plane angle angle indica indicates tes long long anteri anterior or facial vertical dimension and a skeletal open bite 13
tend tenden ency cy,, whil while e a flat flat mand mandib ibul ular ar plan plane e angl angle e often correlates with short anterior facial height and deep bite malocclusion. 2. Tooth –lip relationship: Mini Esthetics a. Tooth Tooth-lip -lip relati relations onship hips s b. Smil Smile e Analy Analysi sis s i. Amount of incisor and gingival display ii.Transverse dimension of smile relative to upper arch iii.The smile arc iv. 3. Dental Appearance: Micro Esthetics a. Toot Tooth h propo proport rtio ions ns i. Width relationships and “Golden Proportion” Proportion” ii.Height- Width relationships b. Gingival Gingival height heights, s, shape shape and and contou contourr c. Connec Connector tors s and and Embr Embrasu asures res d. Embras Embrasur ures: es: Black Black Triang Triangles les? ? e. Tooth Tooth Shade Shade and Color Color
Case History Case History is the information gathered from the patient or parent or guardian to aid in overall diagnosis of the case. It includes personal details, chief complaint, past and present medical and dental history and any associated family history. The aim is to establish a rapport with the patient and to obtain information about individual’s complaint. 1. Personal details A. Name The The patie atient nt’s ’s name ame sho should be reco ecorded ded for for the the purpo urpose se of communication and identification. Addressing a patient by his or her name name has a benefi beneficial cial psycho psycholog logica icall effect effect.. It makes makes the patien patientt more comfortable and arouses a feeling of familiarity. B. Age The age of the patient helps in diagnosis, treatment planning and growth prediction. There are certain transient conditions that occur during development are considered normal for that age. In addition, there there are certai certain n treat treatmen mentt modali modalitie ties s that that are best best carrie carried d out during growing age, like- growth modification using functional and ortho orthoped pedic ic applia appliance nces. s. Surgic Surgical al correc correctiv tive e proced procedur ures es are best best carried out after the cessation of the growth. C. Sex 14
The patient’s sex also helps in treatment planning. The timing of growth related events including growth spurts, eruption of teeth and onset of puberty puberty are different different in males and females. females. Psycholog Psychological ical reaction of males and females may be different towards the same malocclusion. Females are more concerned about facial esthetics. D. Address and contact number It helps in future correspondence and managing the appointments. Patients coming from far may require a different appliance therapy as they might not be able to visit the clinic frequently. E. Occupation It helps in evaluation of the socio-economic status of the patient and helps in the selection of the appropriate appliance. F. Ethnic origin
The ethnic differences should be considered during treatment. E.g. in Americ American an blacks blacks,, arch arch size size is notabl notably y larger larger and arch arch form form is squarer and less tapered compared to American whites. 1. Chief Complaint The patient’s chief complaint should be recorded in his or her own words. There are three logical reasons for patient concern about the alignment and occlusion of the teeth: impaired dentofacial esthetics that can lead to psychosocial problems; impaired function; and a desire to improve improve dentofacial dentofacial esthetics. esthetics. It is important important to establish establish their relative importance to the patient and their desires. The parents’ perception of the malocclusion should be noted. A seri series es of lead leadin ing g ques questi tion ons, s, begi beginn nnin ing g with with,, "Tel "Telll me what what bothers you about your face or your teeth," may be necessary to clarify what is important to the patient. The orthodontist may or may not agree with the patient’s assessment – the judgement comes later. But, at this stage, it is necessary to find out what is important to the patient. Thi This s will will help help in sett settin ing g trea treatm tmen entt obje object ctiv ives es and and sati satisf sfyi ying ng the the patient and or parents in general. 2. Medical History Knowledge of the patient’s general health is essential and should be obtain ained prior to the exami amination. It is best obtained by questionnaire. In most of the cases, orthodontic treatment can be undertaken but precautions should be taken prior to surgical procedures. Patients with rheu rheuma mati tic c feve fever, r, cardi cardiac ac anom anomal alie ies, s, epil epilep epsy sy,, diab diabet etes es and and bloo blood d dyscrasias may require special precautions. The medical history should include information on drug usage. The use use of cert certai ain n drug drugs s like like aspi aspiri rin n (pro (prost stag agla land ndin in inhi inhibi bito tors rs)) or bone bone resorptio resorption n inhibiting inhibiting agents agents may impede impede orthodon orthodontic tic tooth tooth movement. movement. Patients who are suffering from acute, debilitating conditions such as 15
viral fever should be allowed to recover prior to initiating orthodontic treatment. Histor History y of trauma trauma should should be noted. noted. Trauma Trauma to the jaws jaws or teeth is often overlooked in child with other trauma, so a jaw injury may not have have been been diagno diagnosed sed at that that time. time. This This is signif significa icant nt as it affect affects s the future development of jaws and teeth. 3. Dental History The patient’s dental history should include information on the age of eruption and exfoliation of deciduous and permanent teeth, history of extraction extraction,, decay, restoration restorations s and trauma. trauma. The past dental dental history history will also help in assessing the patients and parents’ attitude towards dental health. 4. History of Habits History of abnormal habits like finger, digit sucking, nail biting, lip biting grinding, clenching, and mouth breathing should be taken as they influence the development of dentoalveolar structures. Pre- natall H istory isto ry 5. Pre-nata Pre-natal history should include information on the condition of the mother during pregnancy and the type of delivery. Forceps deliveries have been associated with injury to the temporomandibular joint (TMJ) and may cause ankylosis and mandibular growth retardation. Nutrition status and infections during pregnancy should also be noted. 6. Post-natal History It should include information on type of feeding, presence of habits and milestones of normal development.
7. Family History Many Many malocc malocclus lusion ions s like like skelet skeletal al Class Class II and Class Class III, III, crowdi crowding, ng, spacing spacing overjet, overjet, high frenal attachmen attachments ts and congenital congenital conditions conditions like cleft lip and palate are inherited. 8. Physical Growth evaluation The parents should be questioned about the child’s growth status. (e.g.: Has your child had any recent rapid growth?). Rapid growth during the adoles adolescen centt growt growth h spurt spurt facili facilitat tates es tooth tooth moveme movement nt but growt growth h modification may not be possible in a child who is beyond the peak of the growth spurt. For children approaching puberty, questions about how rapidly the child has grown recently, whether clothes sizes have changed, whether ther there e are are sign signs s of sexu sexual al matu matura rati tion on,, and and when when sexu sexual al matu matura rati tion on occur occurred red in older older siblin siblings gs usuall usually y provi provide de the necess necessary ary infor informat mation ion about where the child is on the growth curve.
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In orthodontic clinic, measuring the height and weight regularly and calculation of bone age from vertebrae as seen in the cephalometric radiograph can be helpful. Serial cephalometric radiographs offer the most most accu accura rate te way way to dete determ rmin ine e whet whethe herr grow growth th has has stop stoppe ped d or is continuing. 9. Social and Behavioral Evaluation It should explore – patient’s motivation for treatment, what he or she she exp expect ects as a resul esultt of trea treatm tmen entt and how how co-o co-ope perrativ ative e or uncooperative the patient is. Motivation can be external or internal. External motivation is that suppli supplied ed by pressu pressure re from from anothe anotherr indivi individua dual, l, like child child broug brought ht for treatment by mother; older patient by his girlfriend. Internal motivation come comes s from from with within in the the indi indivi vidu dual al and and is base based d upon upon his his or her her own own assessment of the situation and desire for the treatment. What What pati patien entt expe expect cts s from from the the treat treatme ment nt shou should ld be expl explor ored ed carefully especially in case of patients with primarily cosmetic problems.
Clinical Examination 1.
General Examination
Each patient should be regarded as a whole person rather than as a 'pair of jaws'. The examination, therefore, begins immediately the patient ente enters rs the the clin clinic ic.. If poss possib ible le,, both both pare parent nts s shou should ld be pres presen entt at the the exam examin inat atio ion; n; this this affo afford rds s an oppo opport rtun unit ity y to obse observ rve e any any here heredi dita tary ry character characters s which may be present, present, and also an opportuni opportunity ty to discuss discuss the medical history, diagnosis and treatment. A. Height and weight It gives a clue to the physical growth and maturation of the patient. The growth of the body in general is related to the growth of the jaws and face particularly. B. Gait Gait Gait is the the way way a pers person on walk walks. s. Abno Abnorm rmal alit itie ies s of gait gait are are usually associated with neuromuscular disorders. C. Built Sheldon classified body built into: i. Ectomo Ectomorp rphic hic : Tall Tall and thin thin physiq physique ue ii. Mesomorphic : Average physique iii. Endomorphic : Short and obese physique
1.
Extra-oral Examination A. Shape of Head 17
The overall head shape is closely related to the bony structures of the skull and to the shape of the underlying brain. Alterations in head shape can be the result of unusual brain growth, but they may also reflect a number of other factors such as premature synostosis of cranial crani al sutu sutures res or unus unusual ual intr intrauter auterine ine mech mechanical anical forc forces. es. Abnor Abnormal mal planes pla nes of mus muscle cle pul pull, l, as in tor tortic ticoll ollis, is, can cau cause se asy asymme mmetri tric c sku skull ll growth. Five major sutures are present in the calvaria. Coronal, lambdoidal, and squamosal are paired; and sagittal and metopic are single. Cranial growth normally proceeds in a direction perpendicular to each of the major sutures. Increased length of the skull in comparison to width (dolichocephaly or scaphocephaly) and the converse (brachycephaly) can be no norma rmall var varian iants. ts. Ho Howev wever, er, bot both h can also occ occur ur bec becaus ause e of premature synostosis of cranial sutures, where skull growth at right angles to the fused suture is inhibited with compensatory expansion at other patent sutural sites. Head shape depends on which sutures are prematurely synostosed, the order in which they fuse, and the time at which they synostose. Fontanelles
Sutures
Sutures and fontanelles Dolichocephaly can occur with early closure of the sagittal suture, produc pro ducing ing a lon long, g, nar narro row w cra craniu nium.W m.When hen bot both h sid sides es of the cor corona onall suture are prematurely fused, the head is brachycephalic. Unilateral synostosis of the coronal suture results in asymmetry of head shape or plagiocephaly. The frontal eminence on the fused side is flattened and the glabella region is underdeveloped. The eyebrows and orbit on the affect aff ected ed sid side e app appear ear elev elevate ated. d. Pre Premat matur ure e clo closur sure e of on one e lam lambdo bdoid id sutu su ture re ca can n si simi mila larl rly y re resu sult lt in pl plag agio ioce ceph phal aly. y. In tr trig igon onoc ocep epha haly ly,, premat pre matur ure e syn synost ostosi osis s of the met metop opic ic sut suture ure re resul sults ts in a tri triang angula ularr promin pro minenc ence e of the fro fronta ntall bon bone, e, usu usuall ally y in ass associ ociati ation on wit with h ocu ocular lar hypotelorism. Metopic ridging may occur.
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The The shape shape of head head can be evalua evaluated ted based on the cephalic cephalic index index which is based on the anthropometric determination of the maximum width and maximum length of the head. It is given by Martin and Saller as:Cephaic index Maximum ×100 skull width = Maxim um skull length • • •
•
Mesocephalic : I = 76.0 -80.9 Brchycephalic : I = 81.0- 85.4 Broad and short head Dolicocephalic : I < 75.9 Long and narrow head Hyperbrachycephalic : I > 85.5
Skull Length is the maximum dimension of the sagittal axis of the skull. It is measured as the distance between the glabella (the most prominent point on the frontal bone above the root of the nose, between the eyebrows) and the opisthocranion (the most prominent portion of the occiput, close to the midline on the posterior rim of the foramen magnum). Skull Sku ll wid width th is mea measur sured ed bet betwee ween n the most lat latera erall poi points nts of the parietal parie tal bones (eurion) (eurion) on each side of the head. The measurement measurement is done with spreading calipers.
Measuring skull length and skull width
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A. Shape of the face The shape of the face is assessed by morphologic facial index which was given by Martin and Saller(1957) as: ×100 Morphologic facial height Facial index (I) Bizygomatic width = • •
•
•
•
Hypereuryprosopic Hypereuryprosopic : I < 78.9 Euryprosopic Euryprosopic : I = 79.0 – 83.0 – Broad and short facial form Mesopros Mesoprosopic opic : I = 84.0 – 87.9 – Average Average or normal normal facial form Letoprosopic : I = 88.0 – 92.9 – Long and narrow facial form Hyperleptoprosopic Hyperleptoprosopic : I > 93.0
Facial height is the distance from the root of the nose (nasion) to the low lowest est med median ian lan landma dmark rk on the low lower er bor border der of the mandible mandible (men (m ento ton n or gn gnat athi hion on). ). Th The e me meas asur urem emen entt is do done ne wi with th sp spre read adin ing g calipers. A tape-measure can be used but should be held parallel to the sagittal axis of the face, in front of the tip of the nose. Bizygomatic width is the maximal distance between the most lateral points on the zygomatic arches (zygion), localized by palpation.
Measuring bizygomatic width and the facial height A. Assessment of facial symmetry
A certain degree of asymmetry between right and left sides of the the face face is seen seen in most most of the the indi indivi vidu dual als. s. The The face face shou should ld be exam examin ined ed in the the tran transv sver erse se and and vert vertic ical al plan planes es to dete determ rmin ine e a greater degree of asymmetry than the normal. Gross facial asymmetries may be seen in patients with• Hemifacial atropy/hypertrophy atropy/hypertrophy • Congenital defects • Unilateral condylar hyperplasia • Unilateral Ankylosis 20
A. Facial profile The profile is examined from the side by making the patient view at a distant object, with the FH plane parallel to the floor. The profile is assessed by the two reference linesA line joining the forehead and the soft tissue point A (deepest point in the curvature of upper lip) A line line join joinin ing g poin pointt A and and the the soft soft tiss tissue ue pogo pogoni nion on (mos (mostt anterior point of the chin) Base Based d on the the rela relati tion onsh ship ip betw betwee een n thes these e two two line lines, s, thre three e types of profile exists Straight : The two two lines form form a nearly nearly straight line Convex Convex : The two lines lines form form an angle with with the concav concavity ity facing the tissue. It occurs in cases of prognathic maxilla or retrognathic mandible mandible as seen in Class II Div I. Concav Concave e : The two refere reference nce lines form an angle angle with with the convexity towards the tissue. This type of profile is seen in Class III patients.
Convex
Straight
Concave A. Facial divergence It is defined as an anterior or posterior inclination of the lower face relative to the forehead. Facial divergence is determined by a line drawn from forehead to the chin Anterior divergence : The line is inclined anteriorly. Posterior divergence : The line is inclined posteriorly. Straight or orthognathic : The line is perpendicular to the floor, no slanting.
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Straight
Posteriorly
Anteiorly Diverging
diverging A. Assessment of antero-posterior jaw relationship
The antero-posterior jaw relationship between the upper and lower jaw can be assessed to certain extent clinically by placing index and middle fingers at the approximate A and B points after lip retraction. Ideally the maxillary skeletal base is 2-3mm forward of the mandibular skeletal base when the teeth are in occlusion. In skeletal Class II patients, the index finger is anterior to the middle finger or the hands point upward. In skeletal Class III patients, the middle finger is anterior to the index finger or the hands points downwards. In skeletal Class I patients, the hand is at even level.
B. Assessment of vertical jaw relationship
Normally, the distance between glabella to subnasale is equal to the distance between the subnasale to the underside of the chin. Reduced lower facial height is associated with deep bite while the increased facial height is with anterior open bite. The vertical skeletal relationship can also be assessed by stud studyi ying ng the the angl angle e form formed ed betw betwee een n the the lowe lowerr bord border er of the the mandib mandible le and the Fra Frankf nkfor ortt horizo horizonta ntall plane. plane. Normal Normally, ly, the two planes intersect at the occipital region. In case the two planes meet beyo beyond nd the the occi occipi pita tall regi region on,, it indi indica cate tes s a low low angl angle e case case or hori horizo zont ntal al grow growin ing g face face.. If the the two two plan planes es meet meet ante anteri rior or to the the occipital region it indicates a high angle case or a vertical growing face.
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C. Evaluation of facial proportion
A well proportioned face is divided into three equal vertical thirds using four horizontal planes- at the level of the hair line, the supraorbital ridge, the base of the nose and the inferior border of chin. Within the lower face, the upper lip occupies one third of the distance.
D. Lips
In the ideal lip form, the vertical dimension is such that, with the lip muscles in their position of resting posture, the lips meet tog togethe etherr. In this this cond condit itio ion n of rest, est, ther there e is minim inimal al muscle scle contra contracti ction on to mainta maintain in the posit position ion of the lips. lips. Consid Considera erable ble variation occurs in the resting lip form.
Compet Comp eten ent: t: Slig Slight ht cont contac actt of lip lip when when the the musc muscul ulat atur ure e is relaxed. Incomp Incompete etent: nt: Anatom Anatomica ically lly short short lips lips which which do not not contac contactt when when muscul musculatu ature re is relaxe relaxed. d. Lip seal is achiev achieved ed only only by active contraction of the orbicularis oris and mentalis muscle. Potentially competent: Normal lips which fail to form the lip seal due to proclined upper incisors. Everted lips: Hypertropied lips with weak muscular tonicity. tonicity.
If they are of sufficient size to be together at rest then lip closure will not place extra forces on the teeth. If the lips at rest are apart, apart, then then muscul muscular ar contra contracti ction on will will be requir required ed to bring bring them them together during swallowing and speech, and such contraction will impo impose se extr extra a forc forces es on the the erup erupti ting ng teet teeth. h. Furt Furthe herm rmor ore, e, some some people, whose lips do not meet at rest, maintain a conscious lip 23
closure for much of the time, again imposing muscular forces on the teeth. The effect of these forces on the erupting teeth depends to a large extent on the sagittal relationship of the lips. The The sagit agitttal relat elatio ions nsh hip of the the lip lips is almo almost st enti entirrely ely determined by the relationship of the basal bone of the jaws, to which they are attached. The lower lip tends to be further back than the upper lip in a skeletal Class 2 relationship, and further forward in a skeletal Class 3 relationship. This not only increases the difficulty of putting the lips together, but also may cause the lower lip to modify the eruptive path of the upper incisors. Such modification may alter the primary primary effect effect of the skeletal skeletal relati relations onship hip on the occlusal relationship of the teeth, either increasing or reducing the effect of any skeletal discrepancy. For example, with a skeletal Class 2 relationship the lower lip may function completely or partly behind the upper incisors. If the skeletal discrepancy is not severe, the lip may procline the upper incisors so that the occlusal relationship is more severely Class 2 than the skeletal relationship (fig a). If the skeletal discrepancy is severe, the lower lip may function behindFig thea upper incisors Fig without b causing them to be proclined (fig b). In other instances, with skeletal Class 2, the lower lip functions entirely in front of the upper incisors, causing them to be retroclined into the Class 2 Division 2 incisor relationship. It is equally possible for lip activity to produce Class 2 or Class 3 occlusal relationships on a Class I skeletal relationship by altering the inclination of the incisor teeth during eruption. The level at which the lips meet together in normal function is usually called the 'lip-line'. The position of the lip-line in relation to the incisor incisor teeth teeth plays plays a part part in govern governing ing the positi position on of those those teeth. The ideal level of the lip-line is approximately at the centre of the crowns of the upper incisor teeth, with the lower lip in front of the upper incisors. The lip-line may be low, in which case part of the lower lip may func functi tion on behi behind nd the the upper incisors, incisors, causing causing proclination. If the lower lip functi functions ons comple completel tely y behind the upper incisors the definition of lip-line is not not stri strict ctly ly appl applic icab able le.. The lip-line may be high, as is common in Class 2 24
Division 2 occlusal relationship. This is usually brought about by the fact fact that that retro retrocli clinat nation ion of the inciso incisors rs result results s in the inciso incisors rs not meeting correctly, with consequent continued development of upper and and lowe lowerr inci inciso sors rs and and rela relate ted d alve alveol olar ar bone bone in the the vert vertic ical al dimension. The upper incisors are thus too far down in relation to the lips, and the lip-line is high
a d
b
c
(a) The ideal level, the lower lower lip controlling the the upper incisors, incisors, (b) A low lip-line, the lower lower lip functioning partly partly behind the upper upper incisors, (c) The lower lip functioning completely completely behind the upper incisors, (d) A high lip-line, the lower lower lip exerting extra extra control over the upper incisors, which are retroclined. The Ricketts‘ E-line, the reference line connecting the tip of the nose with the soft tissue pogonion, passes about 4 mm in front of the upper lip and 2 mm in front of the lower lip.
A. Nose
The nose, with its central position, plays a major role in facial aesthetics and the parameters that one must consider in clinical nasal analysis are impressive.
Size: Normally nose is one third of the total facial height. 25
Contour: Shape can be straight, convex or crooked. Nostril: Nostril: Normally Normally they are oval oval and bilaterally bilaterally symmetr symmetrical. ical. Asymmetry may indicate nasal obstruction.
A. Nasolabial angle It is the angle formed between the lower border of the nose and a line joining the subnasale with the tip of the upper lip (labrale superius). The angle is normally 110 o. It is reduced in patients with proclined upper anteriors or prognathic maxilla. B. Chin
Chin Chin posi positi tion on and and prom promin inen ence: ce: Prom Promin inen entt chin chin is usua usuall lly y associated associated with Class Class III malocclusio malocclusion n while recessive recessive chins are common in Class II malocclusion. Mentolabial sulcus: It is the concavity present below the lower lip. lip. Deep Deep sulc sulcus us is seen seen in clas class s II case cases s wher where e as shal shallo low w sulcus is seen in bimaxillary protrusion. Mental Mentalis is activi activity: ty: Normal Normally, ly, the mental mentalis is muscle muscle does does not show any contractio contraction n at rest. rest. Hyperactive Hyperactive mentalis activity activity is seen in some malocclusion such as Class II division 1 cases. It causes puckering of the chin.
1. Intra-or Intr a-oral al Examina Exam inatio tion n A. Tongue Abnormalities of tongue can upset the muscle balance and equili equilibri brium um leadin leading g to malocc malocclus lusion ion becaus because e it counte counterac racts ts the action of buccinator. Short lingual frenum called tongue tie leads to impaired tongue movement. Pres Presen ence ce of exce excess ssiv ivel ely y larg large e tong tongue ue is indi indicat cated ed by the the presence of imprints of teeth on the lateral margins of the tongue giving a scalloped appearance. Large tongue(macroglossia) can be because of the absolute increase in size or because of the narrow arch. Individuals who appear to have a large tongue almost always have a well-developed mandible, but it is very difficult to establish tongue size. Only in extreme cases, as with a patient with earlyonset thyroid deficiency, is it possible to be reasonably sure that an enlarged enlarged tongue tongue contribute contributed d to excessive excessive growth of the mandible. This is unlikely to be a major cause of mandibular prognathism. B. Pala alate Palate is examined for the following findingsVariation ions s in palat palatal al depth depth are associ associate ated d with with variat variation ion of i. Variat facial form. Brachycep Brachycephalic halic patients have broad and shallow shallow palates where as dolicocephalic patients have deep palates. ii. Prese Presence nce of swelli swelling ng indicate indicates s impact impacted ed tooth, tooth, cysts or bony pathology.
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Mucosal ulceration ulceration and indentatio indentations ns is feature feature of traumatic traumatic iii. Mucosal deep bite, especially in case of Class II malocclusion. iv. The third rugae is usually in line with the canine. It helps to assess maxillary anteriors proclination. v. Pres Presen ence ce of of clef clefts ts.. A. Gingiva The gingiva should be examined for inflammation, recession, muco mucogi ging ngiv ival al lesi lesion ons. s. Loca Locall ging gingiv ival al lesi lesion ons s may may occu occurr due due to occlusal occlusal trauma, trauma, abnormal abnormal functional functional loadings loadings or medication medications s (eg: Dilantin, Phenytoin). In mouth breathers, open lip posture causes dryness of the mouth leading to anterior marginal gingivitis. B. Frena Frenall atta attachm chment ents s The maxillary labial frenum can be thick, fibrous and have low attachment attachment.. Such attachments attachments prevent prevent the two maxillary central incisors from approximating each other leading to midline diastema. Mand Ma ndib ibul ular ar labi labial al fren frenum um if with with high high atta attach chme ment nt,, may may lead lead to recession of gingiva. Abnormal frenum attachments can be diagnosed by blanch test test (whe (when n the the uppe upperr lip lip is stre stretc tche hed d upwa upward rds s and and outw outwar ards ds,, blanching in the region of the interdental papilla indicates abnormal frenum attachment). C. Tonsi Tonsils ls and and Adenoi Adenoids ds The The size size and and infl inflam amma mati tion on of tons tonsil il shou should ld be exam examin ined ed.. Abnorm Abnormall ally y inflam inflamed ed tonsil tonsils s cause cause altera alteratio tion n in tongue tongue and jaw post postur ure e ther thereb eby y upse upsett ttin ing g the the orooro-fa faci cial al bala balanc nce e lead leadin ing g to malocclusion. D. Dentition and dental arch
i. Status Status The The number numbers s of teeth teeth presen present, t, decidu deciduous ous or perman permanent ent;; missing or unerupted teeth; extracted due to some reasons must be recorded. ii.Presence of caries, restoration, malformation, hypoplasia, wear and discoloration.
⇒
iii.Molar relation Mola Mo larr rela relati tion on is defi define ned d as the the rela relati tion on betw betwee eeen en maxillary and mandibular first molars. It can be of Class I: Mesio-buccal cusp of maxillary first molar occludes in the buccal groove of the mandibular first molar.
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⇒
Class II: Mesio-buccal cusp of maxillary first molar occludes in the groove groove betwee between n mandib mandibula ularr 2nd premol premolar ar and 1st molar.
○ ○
⇒
Div 1: With proclined maxillary incisors. Div 2: Lingually inclined maxillary central incisors with labially tipped lateral incisors overlapping the centrals. Lingua Linguall inclin inclinati ation on of centr central al and latera laterall inciso incisors rs with with canines labially tipped can also occur.
Class III: Mesio-buccal cusp of maxillary first molar occludes in the groove between mandibular 1 st and 2nd molar.
•
•
•
•
•
When there is Class II molar relation on one side, and Class I on other side, it is called Class II subdivision. When there is Class III molar relation on one side and Class I on other side, it is called Class III subdivision. When there is Class II molar relation on one side and Class II on other side, it is called Class IV relation. When When mesi mesiob obuc ucca call cusp cusp of maxi maxill llar ary y firs firstt mola molarr occlud occludes es with with the mesiob mesiobucc uccal al cusp cusp of mandib mandibula ularr first molar, it is called end-on molar relation. When mesiobuccal cusp relation is between Class I and Class III, it is called Super Class I relation.
Dewey’s modification of Angle’s Class I malocclusion TYPE 1:-Angle’s class I with crowded maxillary anterior teeth. TYPE 2:- Angle’s class I with maxillary incisor in labio-version (proclined). TYPE 3:- Angle’s class I with maxillary incisor teeth on linguoversion to mandibular incisor teeth (anterior in cross bite) 28
TYP TYPE E 4:4:- Mo Mola larr and/ and/or or prem premol olar ars s are are in bucc bucco o or ling linguo uo-ver versio sion,bu ,but incs incsor ors s & can canines ines ar are e in nor normal mal alig alignm nmen entt (posterior in crossbite) . TYPE 5:- Molars are in mesioversion due to early loss of teeth mesi mesial al to them them (Ear (Early ly loss loss of deci decidu duou ous s mola molars rs or seco second nd premolar) . Dewey’s modification of Angle’s Class III malocclusion TYPE TYPE 1:- Indivi Individua duall arches arches when when viewed viewed indivi individua dually lly are in normal alignment, but when in occlusion the anterior are in edge to edge bite. TYPE 2:- The mandibular incisors are crowed & lingual to the maxillary incisors. TYPE 3:- Maxillary arch is underdeveloped, in cross bite with maxi maxill llar ary y inci inciso sors rs crow crowde ded d & the the mand mandib ibul ular ar arch arch is we well ll developed & well aligned. Lischer’s modification of Angle’s Angle’s classificationLisc Lische herr in 1933 1933 furt furthe herr modi modifi fied ed angl angle’ e’s s clas classi sifi fica cati tion on by substitut substitute e names for Angle’s Class I, II & III malocclusion malocclusion he also proposed terms to designate individual tooth malp alpositi sitio ons 1) Neut Neutro roo occlu cclusi sion on 2) Dist Disto oocclu cclusi sio on 3) Mesioocclusion i. Incisor Incisor relation relation Britis itish h stan stand dar ards ds relationship⇒
⇒
⇒
Inst Instit itu ute
Cla Classif ssific icat atio ion n
of
inci inciso sorr
Cla Class I : Low Lower inci incis sor edge edges s occlu cclud des with ith or lie lie immediately below the cingulum plateau of upper central incisors. Class Class II : Lower Lower inciso incisorr edges edges lie poster posterior ior to cingul cingulum um plateau. Two subdivisions of this category are – Div 1 – The upper central incisors are proclined or of ○ aver averag age e incl inclin inat atio ion n and and ther there e is an incr increa ease se in overjet. Div 2 – The upper centra centrall inciso incisors rs are retrocli retroclined ned.. ○ Overjet is usually minimal or may be increased. Class III : The lower incisor edges lie anterior to cingulum plateau. The overjet may be reduced or reversed.
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Class I
Class
Class II Div 1 Div 2
Class II
i. Canine Canine relation ⇒ Class I : The mesial incline of upper canine overlaps the distal slopes of the lower canine. ⇒ Class II : Distal slope of maxillary canine occludes or contact the mesial slope of lower canine. ⇒ Class III : Lower canine is displaced anteriorly to the upper canine with no overlapping of upper and lower canine. i. Overje Overjett It is defined as the horizontal overlap between the maxillary and mandibular incisors. ⇒ Nor Normal over overje jet: t: The inci incisa sall edg edges of maxil axilla larry incisors are 2-3mm ahead of mandibular incisors. ⇒ Incr Increa ease sed d ovej ovejet et:: Hori Horizo zont ntal al over overla lap p more more than than normal. ⇒ Decr Decrea ease sed d over overje jet: t: Hori Horizo zont ntal al over overla lap p less less than than normal. ⇒ No over overje jett (Edg (Edge e to edge edge): ): The The inci incisa sall edge edges s of maxi maxill llar ary y and and mand mandib ibul ular ar inci inciso sors rs are are in same same vertical plane. ⇒ Re Reve vers rse e over overje jett (Cro (Cross ss bite bite): ): Ma Mand ndib ibul ular ar inci inciso sors rs edge edges s are are forw forwar ardl dly y plac placed ed than than the the maxi maxill llar ary y incisors edges. i. Overbite.
It is defined as the vertical overlap between maxillary and mandibular incisors. 30
⇒
⇒
Normal overbite: The upper incisors cover the incisal third of the lower incisors. Incr Increas eased ed over overbi bite te (Dee (Deep p bite bite): ): Lowe Lowerr inci inciso sors rs converage more than normal. Comp Co mple lete te deep deep bite bite:: Ther There e is a con contact tact between the lower incisal edge and tooth or soft tissue of the palate. Inco Incomp mplet lete e deep deep bite bite:: Ther There e is no cont contac actt between the lower incisor edge and tooth or soft tissue of the palate. Decr Decrea ease sed d over overbi bite te:: The The vert vertic ical al over overla lap p of the the mandibular incisors is less than normal. Edge to edge bite: The incisal edges of upper and lower incisors are in contact. No overbite (open bite): No vertical overlap. ○ Anterior open bite: No overlap of incisors. Post Poster erio iorr open open bite bite:: No over overlap lap of post poster erio iorr ○ teeth. ○
○
⇒
⇒
⇒
Midlin ine e of the the face face and and its its coin coinci cide denc nce e with with the the dent dental al i. Midl midline. The The midl midlin ine e of the the face face shou should ld coin coinci cide de with with the the midline of the face. Deviations can be seen in crowding, rotation of the dental arch around the vertical axis. ii.Individ ii.Individual ual tooth tooth irregular irregularities ities like rotation, rotation, displacemen displacement, t, fracture. Lischer classified individual tooth irregularity as• Buccoocclusion: Buccal placement • Linguoocclusion: Lingual placement • Supraocclusion: Eruption beyond the normal level • Infraocclusion: Not erupted to the normal level • Mesioversion: Mesial to normal position • Distoversion: Distal to normal position • Transversion: Transposition Transposition of two teeth • Axiversion: Abnormal axial inclination of a tooth • Torsiversion: Rotation of tooth around its long axis. i. Shape and symmetry of of the upper and lower jaws. Arch Arch can can be bila bilate tera rall lly y symm symmet etri ric c or asym asymme metr tric ic.. Asymmetry within the dental arch, but with symmetric arch form, also can occur. It usually results either from lateral drift of incisors or from drift of posterior teeth unilaterally. Tansparent ruled grid placed over the upper dental arch and oriented to the midpalatal raphe can make it easier to see a distortion of arch form. The The ar arch ch for form can can be cla classif ssifie ied d as (Thom Thomps pso on’s Classification):
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Elliptical
Round
U- Shaped
V-
Shaped
1. Functio Func tional nal Examina Exam inatio tion n Normal functioning of stomatognathic system promotes normal growth growth and developmen developmentt of oro-facial oro-facial complex. Improper Improper functionin functioning g can result result in various various malocclusi malocclusions. ons. Therefore Therefore,, orthodont orthodontic ic diagnosis diagnosis shou should ld not not be rest restri rict cted ed to stat static ic eval evalua uati tion on of teet teeth h and and thei theirr supporting structures but should include examination of the functional units of stomatognathic system. It is important to note in the beginning whether the patient has normal coordination and movements. If not, as in an individual with cere cerebr bral al pals palsy y or othe otherr type types s of gros gross s inco incoor ordi dina nati tion on,, norm normal al adaptation adaptation to the changes in tooth tooth position position produced by orthodon orthodontics tics may not occur, and the equilibrium effects may lead to post-treatment relapse. The functional examination should includeA. Assessment Assessment of postural postural rest rest position position and inter-occlusa inter-occlusall clearance clearance The postural rest position is the position of the mandible at whic which h the the musc muscle les s that that clos close e the the mand mandib ible le and and that that open open the the mandible are in the state of minimal contraction. At rest position, a space space exis exists ts betw betwee een n the the uppe upperr and and lowe lowerr jaw jaw whic which h is call called ed interocclusal clearance or freeway space which is normally 3mm in canine region. The The post postur ural al rest rest posi positi tion on shou should ld be dete determ rmin ined ed with with the the patient relaxed and seated upright with back unsupported. The head
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is oriented by making the FH plane parallel to the floor. Methods to assess postural rest position arePhon Phonet etic ic meth method od:: The The pati patien entt is told told to pron pronou ounc nce e some some conson consonant ants s like like “M” or words words like like “Miss “Mississ issipp ippi” i” repeat repeatedl edly. y. The mandible returns to the postural rest position 1-2 seconds after the exercise. ii. Comman Command d method: method: The patient patient is asked asked to perfor perform m selected selected func functtion ions like like swal swallo low wing. ing. The The mand mandib ible le then then retu eturns spontaneously to rest position. method: The patient is observed observed as he speaks iii. Non command method: or swallo allows ws.. The pati patien entt is not not awar aware e that that he is bein being g examined. While talking, the patient’s musculature is relaxed and the mandible reverts to the postural rest position. i.
B. Evaluation Evaluation of path of closu closure re The path of closure is the movement of mandible from rest position to habitual occlusion. Abnormalities of path of closure are seen in some form of malocclusion. Forward path of closure: Many children and adults with a skeletal Clas Class s II rela relati tion onsh ship ip and and an unde underl rlyi ying ng sk skel elet etal al Clas Class s II jaw jaw relationship will position the mandible forward in a "Sunday bite," making making the occlus occlusion ion look look better better than it really really is. Someti Sometimes mes an apparent Class III relationship results from a forward shift to escape incisor incisor interferen interferences ces in what is really really an end-to-end end-to-end relationship relationship. These patients are said to have pseudo- Class III malocclusion. Backward path of closure: Class II division 2 cases exhibit premature incis incisor or cont contac actt due due to retr retroc ocli line ned d maxi maxill llar ary y inci inciso sors rs.. Thus Thus the the mandible is guided posteriorly to establish occlusion.
Latera rall devi deviat atio ion n of the the mand mandib ible le is Late Latera rall path path of clos closur ure: e: Late associated with occlusal prematurities and a narrow maxillary arch. C. Examin Examinati ation on of TMJ The functional examination of TMJ should include auscultation and palpation of the temporomandibular joint and the musculature associated with mandibular opening. The patient is examined for the symp sympto toms ms of TM TMJJ prob proble lems ms like like clic clicki king ng,, crep crepit itus us,, pain pain of the the masticato masticatory ry muscles, muscles, limitation of jaw movement, movement, hyper mobility mobility and morphological abnormalities. The maximum mouth opening is determined by measuring the distance between the maxillary and mandibular incisor edge with the mouth wide open. The normal inter incisal distance is 40-45 mm. 33
D. Examination of oral functions
i. Respiration Humans exhibit three types of breathing- nasal, oral and oronasal. There There are some some tests tests which help to diagno diagnose se the mode of respirationa. Mirror test: A double sided mirror is held between the nose and mouth. Fogging on the nasal side of the mirror indicates nasal breathing while fogging towards the oral side indicates oral breathing. b. Cotton Cotton test: test: A butter butterfly fly shaped shaped piece piece of cotton cotton is placed placed over over the upper lip below the nostrils. If the cotton flutters down it indica indicates tes nasal nasal breath breathing ing.. It helps helps to determ determine ine unilat unilatera erall nasal blockage. c. Water test: The patient is asked to fill the mouth with water and retain it for a while. Nasal breathers do it easily while mouth breathers feel difficult. d. Obse Observ rvat atio ion: n: In nasa nasall brea breath ther ers, s, the the exte extern rnal al nare nares s dilat dilate e duri during ng insp inspir irat atio ion. n. In mout mouth h brea breath ther ers, s, ther there e is eith either er no change in the external nares or they may constrict during inspiration.
i. Speech Speech Speech proble problems ms can be relate related d to malocc malocclus lusion ion,, but normal speech is possible in the presence of severe anatomic dist distor orti tion ons. s. Spee Speech ch diff diffic icul ultie ties s in a chil child, d, ther theref efor ore, e, are are unlikely to be solved by orthodontic treatment. If a child has a speech problem and the type of malocclusion related to it, a combination of speech therapy and orthodontics may help. If the speech problem is not listed as related to malocclusion, orthodont orthodontic ic treatment may be valuable valuable in its own right right but is unlikely to have any impact on speech. Patients having tongue thrust habit tend to lisp while cleft palate patients may have a nasal tone. Speech Difficulties Related to Malocclusion: Speech Sound
Problem
/s/, /z/ (sibilants)
Lisp
/t/, /d/ Difficulty (linguoalveolar production stops) /f/, /v /v/ (l (labiodentals Distortion 34
Related malocclusion Anterior open bite, large gap between incisors in Lingua Linguall positi position on of maxillary incisors
Skeletal Class III
fricatives) Th, sh, chDistortion (linguodental fricatives fricatives [voiced or voiceless])
Anterior open bite
ii. ii. Swall wallo owing ing In a new new bor orn n, the the tong tongue ue is relat elativ ivel ely y lar large and protrudes between the gum pads and takes part in establishing the lip seal. This kind of swallow is called infantile swallow and is seen till 1.5 to 2 yrs of age. Infantile swallow is replaced by mature swallow as the buccal teeth erupt. The persistence of infantile swallow can be a cause of malocclusion. The persistence of infantile swallow is indicated by the presence ofProtrusion of tip of the tongue. Contraction of perioral muscles during swallowing. No contact at the molar region during swallowing.
1. Evaluation Evaluat ion of Facial and an d Dental Appearance Appea rance A systematic examination of facial and dental appearance should be done in three steps: 1. The face face in all three three planes planes of space space (macro-e (macro-esthet sthetics) ics) 2. The smile framewor framework k (mini-es (mini-estheti thetics) cs) 3. The teeth teeth (micr (micro-e o-esth stheti etics) cs)
1. Facial Proportions: Macro Esthetics a. Assessment of Developmental Age:
The The asse assess ssm ment ent of devel evelop opme men ntal tal age is par arti ticu cula larrly important important for children around the age of puberty when most of the the orth orthod odon onti tic c trea treatm tmen entt is carr carrie ied d out. out. The The degr degree ee of physical development is much more important than chronological age in determining how much growth remains. b. Facial Facial Esthetic Esthetics s vs Facial Facial proporti proportion on Whet Whethe herr a face ace is cons consid ider ered ed beau beauttiful iful or not not is determined determined by ethnic ethnic and cultural cultural factors, factors, a disproport disproportionate ionate face face beco become mes s a psych sycho osoci social al pro problem blem.. Dist Distor orte ted d and and asymme asymmetri tric c facial facial featur features es are a major major contri contribut butor or to facial facial esth esthet etic ic prob proble lems ms;; wher wherea eas s prop propor ortio tiona nate te feat featur ures es are are acceptable if not always beautiful. So the goal of the facial examination is to detect the facial disproportion. i. Frontal Examination A small degree of facial asymmetry exists in all norm normal al indi indivi vidu dual al.. This This norm normal al symm symmet etry ry shou should ld be distinguished from severe disproportion caused due to deviation of chin or nose to one side. 35
Some of the measurements could be made on a ceph cephal alom omet etri ric c radi radiog ogra raph ph but but many many coul could d not. not. It is better better to make make measur measureme ements nts clinic clinicall ally y becaus because e soft soft tissue tissue propor proportio tions ns as seen seen clinic clinicall ally y determ determine ine facial facial proportion. The The dist distan ance ce from from the the hair hair line line to base base of the the nose, base of the nose to bottom of nose and bottom of nose to chin should be same. Similarly, an ideal proportional face can be divided into into cent centrral, al, media ediall and and late laterral equ equal fift fifth hs. The separation of the eyes and the width of the eyes which shou should ld be equa equal, l, dete determ rmin ine e the the cent centra rall and and medi medial al fifths. The nose and chin should be centred within the cent centra rall fift fifth, h, with with widt width h of the the nose nose the the same same as or slightly wider than the central fifth. The interpupillary distance should be equal the width of the mouth. Low set eyes or ears that are unusually far apart (hypertelorism) may indicate either the presence of a syndrome or a microform of a craniofacial anomaly. If a synd syndro rome me is susp suspect ected ed,, hand hands s shou should ld be exam examin ined ed because there are a number of dental digital syndromes.
ii.Profile Analysis Profile analysis gives the same information though in less detail for the underlying skeletal relationships, as obta obtain ined ed from from the the anal analys ysis is of late latera rall ceph cephal alom omet etri ric c radiographs. So, the technique of facial profile analysis is also called “Poor man’s cephalometric ce phalometric analysis”. Assessmen mentt of jaw positi position on in antero antero-pos -poster terior ior 1) Assess plane of space It is exam examin ined ed by plac placin ing g the the pati patien entt in phys physio iolo logi gic c natu natura rall head head posi positi tion on (FH (FH plan plane e is par paralle allell to the the ground). The profile is assessed by the two reference lines36
line joining the forehead and the soft tissue point A. line joining point A and the soft tissue pogonion. These These two lines nearly nearly form form a straig straight ht line. line. A straig straight ht profil profile e wheth whether er it is anterio anteriorly rly or poster posterior iorly ly diverging doesn’t indicate a problem where as concavity or convexity does. 1) Evaluation Evaluation of of lip posture posture and incisor incisor promine prominence nce Dete Detect ctio ion n of exce excess ssiv ive e inci inciso sorr prot protru rusi sion on or retrusion is important because of the effect on space within the dental arches. If incisors protrude, they align themselves on the arc of a larger circle as they lean forward. The teeth protrude excessively if – (i) the lips are prominent and everted, and (ii). The lips are separated at rest by more than 3-4mm. In othe otherr word words, s, exce excess ssiv ive e prot protru rusi sion on of the the inci inciso sors rs is revea eveale led d by promin ominen entt lips lips that that ar are e separated when they are relaxed, so that the patient must strain to bring the lips together over the protruding teeth. For such patients, retracting the teeth tends to improve both lip function and facial esthetics. On the other hand, if lips are prominent but close over the the teet teeth h with withou outt stra strain in,, the the lip lip post postur ure e is larg largel ely y inde indepe pend nden entt of toot tooth h posi positi tion on.. Fo Forr that that indi indivi vidu dual al,, retracting the incisor teeth would have little effect on lip function or prominence. Lip Lip post postur ure e and and inci inciso sorr prom promin inen ence ce shou should ld be evaluated by viewing the profile with the patient’s lips relaxed. This is done by observing the distance that each ea ch lip lip proj projec ects ts forw forwar ard d from from a true true vert vertic ical al line line throug through h the depth of the concavit concavity y at its base (soft (soft tissue points A and B). Lip prominence of more than 2 to 3 mm in pres presen ence ce of lip lip inco incomp mpet eten ence ce indi indica cate tes s dentoalveolar protrusion. Re-evalua luatio tion n of vertic vertical al facial facial propo proporti rtions ons,, and 2) Re-eva evaluation of mandibular plane angle The The mand mandib ibul ular ar plan plane e is visu visual aliz ized ed clinically by placing a finger or mirror handle along the lower border of the mandible. A steep mandibular plane angle indicates long anterior anterior facial vertical dimension and a skeletal open bite tendency, while a flat mand mandib ibul ular ar plan plane e angl angle e ofte often n corr correl elat ates es with with shor shortt anterior facial height and deep bite malocclusion.
2. Tooth –lip relationship: Mini Esthetics a. Tooth Tooth-lip -lip relati relations onship hips s 37
It is important to evaluate the relationship of dentition to the face. The relationship of the dental midline of each arch to the skeletal midline of that arch should be noted (the lower incisor incisor midline related to the midline of the mandible mandible and the upper incisor midline related to the midline of the maxilla). The The vertic vertical al relati relations onship hip of teeth teeth i.e. i.e. the amount amount of incisor display to the lips at rest and on smile is noted. Fina Finall lly, y, it is impo import rtan antt to note note whet whethe herr an up-d up-dow own n tran transv sver erse se rota rotati tion on of the the dent dentit itio ion n is reve reveal aled ed when when the the patient smiles or the lips are separated at rest. It is often called a transverse cant of the occlusal plane or transverse roll of the esthetic line of the dentition. b. Smil Smile e Analy Analysi sis s Facial attractiveness is defined more by the smile than by soft tissue relationship at rest. There are mainly two types of smil smilee- pose posed d or soci social al smil smile; e; and and emot emotio iona nall smil smile. e. The The social smile is reproducible and is the one that is presented to the the worl world d rout routin inel ely. y. The The emot emotio iona nall smil smile e vari varies es with with the the emot emotio ion n bein being g disp displa laye yed. d. The The soci social al smil smile e is the the focu focus s of orthodontic diagnosis. In smile analysis, oblique ¾th view as well as the frontal and profile profile views views is impor importan tant. t. The three things things need need to be considered. i. Amount of incisor and gingival display The elevation of the upper lip on smile should stop at or near the gingival margin so that the entire upper inciso incisorr is seen. seen. Some Some displa display y of gingiv gingiva a is accepta acceptable ble and can be both esthetic and youthful appearing. Lip elevation that doesn’t reach 100% display of the incisor crown is less attractive. It is impo import rtan antt to reme rememb mber er that that the the vert vertic ical al relati relations onship hip of the lip to the incisor incisor will will chang change e over over time with the amount of incisor exposure decreases with age. ii.Transverse dimension of smile relative to upper arch Depe Depend ndin ing g upon upon the the faci facial al inde index, x, a wide wide smil smile e may be more attractive than a narrow one. Wide dental arch arch and narro narrow w buccal buccal corrid corridor or width width (the (the distan distance ce between maxillary posterior teeth- especially premolars and the inside of the cheek) is preferred. The smile arc iii. The The The smil smile e arc arc is defi define ned d as the the cont contou ourr of the the incisal edges of maxillary anterior teeth relative to the curvature of the lower lip during a social smile. For best
38
appearance, the contour of the teeth should match that of the lower lip. A flattened smile arc decreases the attractiveness and makes look older.
3. Dental Appearance: Micro Esthetics a. Toot Tooth h propo proport rtio ions ns i. Width relationships and “Golden Proportion” Proportion” The apparent width of the maxillary anterior teeth on smil smile e and and thei theirr actu actual al mesi mesioo-di dist stal al widt width h diff differ er because of the curvature of the dental arch. For best appearanc appearance, e, the appearance, appearance, the apparent width of the lateral incisor should be 62% of the width of the central incisor, the apparent width of the canine should be 62% the width of the lateral incisor, same for the premolar. This is called “Golden Proportion”. ii.Height- Width relationships The width of the tooth should be 80% of its height. If the height is insufficient, there may be several cause: incomplete eruption in a child, loss of crown height from attrition in older person, excessive gingival height etc. The The disp dispro ropo port rtio ion n and and its its prob probab able le caus cause e shou should ld be noted.
b. Gingival Gingival height heights, s, shape shape and and contou contourr Genera Generally lly the centra centrall inciso incisorr has the highes highestt gingiv gingival al level, the lateral incisor is approximately 1.5mm lower and the canine gingival margin is at the level of the central incisor. For best appearance, the gingival shape of the maxillary lateral incisor should be symmetrical half-oval or half-circle. The maxillary centrals and canines should exhibit a gingival shape that is more elliptical and oriented distally to the long axis of the tooth. The gingival zenith (the most apical point of the gingival tissue) should be located distal to the longitudinal axis of the maxillary centrals and canines, while the gingival zeni zenith th of the the maxi maxill llar ary y late latera rals ls shou should ld coin coincid cide e with with thei theirr longitudinal axis.
39
c. Connec Connector tors s and and Embr Embrasu asures res The The conn connec ecto torr (als (also o refe referr rred ed to as the the inte interd rden enta tall contact area) is where adjacent teeth appear to touch, and may may exte extend nd apic apical ally ly or occl occlus usal ally ly from from the the actu actual al cont contac actt point. In other words, the actual contact point is very small area and the connector includes the contact point and the area above and below that are so close together they look as if they are touching. The normal connector height is greatest between the cent centra rall inci inciso sors rs and and dimi dimini nish shes es from from the the cent centra rals ls to the the posterior teeth. The embrasures (triangular spaces incisal and ging gingiv ival al to the the cont contac actt area area)) are are larg larger er in size size than than the the conn connec ecto tors rs and and the the ging gingiv ival al embr embras asur ures es are are fill filled ed with with interdental papillae.
d. Embras Embrasur ures: es: Black Black Triang Triangles les? ? Short inter erd denal papilla leave an open gingival embrasure above the connectors and these “black triangles” can detract significantly from the appearance of the teeth on smile. In adult, black triangles are formed from loss of gingival tissue related to periodontal disease. But when crowded and rotat rotated ed maxill maxillary ary inciso incisors rs are correc corrected ted ortho orthodon dontic ticall ally y in adults, the connector moves incisally and black triangles may appear. So, both actual and potential black triangles should be noted noted during during the ortho orthodon dontic tic examin examinati ation on and the patien patientt should be prepared for reshaping of the teeth to minimize this esthetic problem. e. Tooth Tooth Shade Shade and Color Color The teeth appear lighter and brighter at a younger age, darker darker and dull dull as age progre progresse sses. s. A normal normal progr progress ession ion of 40
shad shade e chan change ge from from the the midl midlin ine e post poster erio iorl rly y is impo import rtan antt contributor to an attractive and natural appearing smile. The maxillary central incisors tend to be the brightest in the smile, the lateral incisor less so, and the canines least bright. The first and second premolars are lighter and brighter than the canines more closely matched to the lateral incisors. References: Contemporary Orthodontics,, Proffit, Fields, Sarver, FourthEdition Orthodontics: Principles and practice; Graber, Vananrsdall, Vig, Fourth Edition Textbook of Orthodontics, Basic Principles and Practices, Sridhar Premkumar, 4th edition Textbook of Orthodontics : Gurkeerat Singh, 2 nd Edition Orthodontics, The Art and Science: S.I. Bhalajhi , 3rd Edition •
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