2BackgroundsAngle classificationSix keys AndrewCrown formArch form Bolton analysisGolden proportion
3Angle ClassificationMalposition → individual toothBuccal or labial, lingual, mesial, distal, torso (rotation), infra and supra. Impacted Malocclusion → anteroposterior relationships of permanent first molars and canines. Canine relationship: The upper canine fits distal to the lower canineMolar relationship Class I: normal relationships → mesial buccal cusp UFM≡mesial sulcus LFM.Class II: distal buccal cusp UFM≡mesial sulcus LFMClass III: buccal cusp USP≡mesial sulcus LFM
5Angle classification extensionClass II division 1: Narrowing of the upper arch, lengthen and protruding UC. Abnormal function of the lips, nasal obstruction, mouth breathing. Class II division 1 subdivision: class I on one side. Class II division 2: Crownding, overlaping and lingual inclination UCNormal nasal and lip functionClass II division 2 subdivision: class I on one side. Class III subdivision: class I on one side. Mild class II: between class I and class IIMild class III: between class I and class III
7Class I Molar or Class I Canine?
12Four items that you "must complete" for successful orthodontic treatment1. The teeth must be straight at the end of treatment. 2. There must not be any spaces between the front teeth. 3. There must not be any overjet (the patient refers to overjet as "overbite"). 4. The teeth must (generally) bite together at the end of treatment. It is OK to have a bicuspid out of occlusion, but the teeth must not be open molar to molar.
13Six keys Andrew1. Molar relationship : Class I AngleCusp‐embrasure relationship buccallyCusp‐fossa relationship lingually2. Crown angulation: All tooth crowns are angulated mesially (mesio‐distal tip)3. Crown inclination: Incisors are inclined labiallyUpper posterior teeth are inclined lingually, similarly from the canine to the premolars; upper molars are inclined slightly more than the canine and the premolars.
14Angulation and inclination
15Lower posterior teeth are inclined lingually, progressively from canine to molars4. Rotations:Rotations are not present 5. SpacesSpaces are not present between teeth6. Curve of SpeeThe plane is either flat or slightly curve
16Curve of SpeeYes No
17Anterior Crown formCentral incisor crown form:•Triangular‐shaped incisors: need to be reshaped to avoid one‐point contact (→ black triangle and unstable)•Rectangular‐shaped incisors: good esthetics•Barrel‐shaped incisors: do not provide ideal esthetics
19Canine crown formMarkedly curved facial contourNarrow and pointed incisally Wide and flattened incisallyRelatively flat facial contour
22Arch formSquare Ovoid Tapered
23The original arch form is considered the most stable position since this is the "in balance" position of the teeth and surrounding muscles: the neutral zone.Any alteration of this position may result in instability in retention.Relapse tendency after changing arch form (De La Cruz‐1995, Burke‐1998): inter‐canine width. Expansion the lower arch form: 10%.Tapered Ovoid SquareJapaneses 12% 42% 46%Caucasians 44% 38% 18%
24Systemized management of arch form Determine the arch form at the start of treatmentTemplate ♦Computerized cast analysis @Arch wire stocked:Round arch wire (NiTi and SS): ovoid only.019/.025 (.018/.025 ) HANT: three shapes45% ovoid 45% square10% tapered.019/.025 (.018/.025 ) SS: ovoid only →
30Application? •Chose the T –loop arch wire •Adjust for the best fit occlusion
36DIAGNOSIS Collect dataOrthodontic questionaireClinical examinationX‐rays : POG and CEPModelsPicturesCephalometric analysisModel anlysis→ Diagnosis: problem list
37Orthodontic QuestionaireMEDICAL HISTORYUnder a physicians care at this time? Yes/No. ExplainTaking any medication at this time? Yes/No. Specify Allergic to any medication? Yes/ No. Specify Any other allergies? Yes/No. Specify Need to be premedicated (antibiotics) for routine dental procedures? _Yes _No. Specify and reason
38Following diseases or conditions? (If yes, explain and date):AIDS__ Bleeding disorder __ Anemia__ Lung disease__ Cerebral palsy__ Heart condition__ Arthritis__ Hepatitis__ Kidney disease__Rheumaticfever___ Asthma__ Diabetes__ Epilepsy__Injury to face/head__Tonsil/adenoid surgery__ Previous surgery__ Females: Is the patient pregnant? __ Yes __ No
39DENTAL HISTORYDate of last dental examination Any injury to the face/teeth/gum? Explain and date.Any previous orthodontic treatment/consultation? Does the patient:Grind his/her teeth at night? Bite his/her fingernails? Suck thumb, finger, pacifier, etc.? If yes, at what age was the habit discontinued? __yearsHas another member of the family had orthodontic treatment? Whom?
40Medical conditions to be considered in orthodontic treatmentMedical condition Implications ActionAsthma Root resorption Monitor every 6 mo for evidence of EARRAllergies Allergic reaction Determine materials causing allergyCoagulation disorders Bleeding risk Extraction?Diabetes Periodontal disease Monitor adequate control of diabetesEpilepsy, High blood pressureGingival hypertrophyPlaque control, gingivectomy if necessaryHeart valve conditions Endocarditis Premedication when extraction, fitting bandsRheumatoid arthritis TMJ degeneration Monitor TMJXerostomia Caries Fluoride supplement
41PATIENTS ATTITUDE AND MOTIVATION Is the patient aware of the problem? Consultation here prompted by _________________Patients interest in having treatment is: __ Wants treatment ___ Willing if necessary __ UnwillingIf the patient’s teeth were to be changed, how would you like them changed? _______________________________If any features of the face could be changed, what would you like to see? ___________________________________
42GROWTH STATUS: (child patients only)Height__________ cm Weight _________kgFemales: Has the patient started her menstruation? __ Yes __ No. If yes, at what age? ________Males: Voice changes? __ Yes __ No Facial hair growth? __ Yes __ NoHas the patient had any recent rapid growth? ___________ If so, how much?_______________
43Rational for Orthodontic questionaireChief complaintsDetermine patient’s motivation, expectationMedical and Dental historyReveal the causes of problemsRelation between the patient’s conditions and orthodontic treatmentGrowth and developmentTiming of orthodontic treatment
45Macro esthetics: facial proportion General viewDolicofacial, brachyfacial, mesiofacial →Frontal viewVertical ProportionChin height Lower face heightHorizontal Proportion: rule of fifthMidline asymmetry
48The lower third @A. Increase face height:Dolicofacial patternVertical maxillary excess (VME) ♦High lip line: anterior teeth display too much Gummy smileLip length: normal ≠ Short lip ♦Excesssive chin height ♦B. Decrease face heightBrachyfacial patternVertical maxillary deficiencyMandibular defienciency ♦Short chin height ♦
49Dolicofacial•Long and thin faces. Weak muscles of mastication that are not strong enough to hold the teeth together during orthodontic treatment. •Non extraction treatment of these cases may result in bite opening during the treatment. •When extraction, space closes quickly.Be careful when treating a protrusion case
50Mesiofacial•Mesiofacial is not long and thin facial features, and not short and square facial features. •In these cases you can extract and the extraction spaces will close "normally". •You can treat these case types non extraction and the teeth will remain in occlusion during treatment.
51Brachyfacial•Short, square faces with very strong muscles of mastication.•Short clinical crowns with some excess enamel wear on the occlusal surface of the teeth. •In these cases, if you extract, then the extraction spaces will close slowly.
66Convex treatment?Be careful not to set the patients expectations too high for reducing a convex profile: it takes 2‐3mm of tooth retraction to result in 1mm of lip retraction.Move the chin forward to reduce feeling convexLefort I + BSSO for comprehensive treatment
68Mini esthetics: Tooth – lip relationshipPhiltrum heightCommisure heightInterlabial gapIncisal display at restSmile analysisEmotional smile and social smileIncisal display on smileGingival display Smile arcBuccal coridor widthArch formTransverse cant
69Vertical measurementsA: Philtrum heightB: Commisure heightC: Interlabial gapD: Incisal display at restA: Incisal display on smileD: Smile arcC: Gingival display B: Crown height and width
70Emotional smile and social smileMajor zygomaticus muscle Risorius muscle
71Smile arcThe contour of the incisal edges of the maxillary anterior teeth relative to the curvature of the lower lip during a social smile
73Gummy smileCrown lengtheningOrthodontic treatmentLefort I OsteotomyPlastic surgery
74Micro esthetics: gingival and dental appearance Tooth proportion: crown height and widthWidth relationship and golden proportionGingival height , shape and contourConnectors and embrasuresTooth shade and color
75Crown height and widthThe width of central upper incisor should be about 80% of it’s height.The disproportion should be done before orthodontic treatment is completed.
76Width relationship and golden proportion
77Gingival shape and contourGingival shape of upper central incisors and canines is more elliptical.Gingival shape of upper lateral incisors and mandibular incisors is a symmetric half‐oval or half‐circular one.The gingival zenith of central and canine is located distal to the longitudinal axis. The gingival zenith of lateral incisors coincides with the longitudinal axis.
78Connectors and embrasuresConnector # contact point area:Include the areas above and below the contact point.Greatest between the central incisors and diminish from the centrals to the posteriors. Embrasures: triangular spaces incisaland gingival to the connector. Gingival embrasures are filled by interdental papillae. Short interdental papillae → black triangle. Tapered crown form → black triangle
80Open bite Principle: Teeth erupt until they hit something. Open bite: the lower incisor does not contact the upper incisor. There are obvious open bite cases where the teeth are separated in the anterior. In some class II cases where the amount of overlap of the upper incisor vs. the lower incisor is normal (1/3 coverage), but the lower incisor does not contact the tooth nor the palate.
81Tongue thrustA test for anterior tongue thrust is to: Take a small sip of water. Close the teeth together with the lips open. Swallow. A patient with an anterior tongue thrust will either: Not be able to keep his/her lips open. Will tilt his/her head back for gravity to keep the water from squirting forward. Will squirt the water between the teeth forward onto their shirt (child patient). A good exercise to give a patient with an anterior tongue thrust(especially in the presence of open bite or excess anterior overjet) is: Take a small sip of water. Close the teeth together with the lips open. Swallow with the throat muscles. Tell the patient to hold their hand on their throat as they learn this exercise to feel the muscle contraction.
82Functional ShiftForward functional shiftLateral functional shift Unilateral crossbiteDental midlines not centered.The asymmetric face from the frontal view.
84Missing ToothThis seems very obvious, but in many cases where a tooth has been lost, the space has closed spontaneously by dental drifting. It is very easy to not notice a missing tooth in a dental arch when doing your examination. Be certain that you count 4 incisors, 2 canines, 4 bicuspids, etc. in each arch, before checking "none."
85Lower Anterior Tissue ThicknessPrinciple: The lower arch is considered the limiting arch in edgewise diagnosis. To align crowded teeth, advancement (forward movement) of the teeth will inevitably occur. If the advancement of the lower incisors is significant, then a periodontal defect (stripping of gingival tissue is the most common) can occur. Advancement of incisors with "thin tissue" has more risk than advancement with "thick tissue" labial to the lower incisors. As the teeth advance, the tissue will become thinner.
87Cephalometric analysis: lanmarks
95SNBMandible is protrusive if > 83Mandible is average if 76 – 82 Mandible is retrusive if <75
98Cephalometric analysis – Skeletal Description Measurement Mean Range Pal. plane to Md. Plane: Skeletal Open/closedANS‐PNS to Md. plane 280 Closed 240 – 330 OpenMd. Plane angle: Skeletal Open/closed FH – MA: Child Adult 260220Closed 200 – 300 Open240 – 330Y – Axis Vert/Hor Growth SGN ‐ FH 590 Hor. 570 – 620 VerticalMaxilla to Cranium N ⊥ A +1mm Retruded ‐1 to +3 ProtrudedMaxilla to Cranium SNA 820 Retruded 760 – 830 ProtrudedMandible to Cranium N ⊥ Po : Child Adult‐7mm‐1mmRetruded ‐10 to ‐4 Protruded‐4 to ‐1Mandible to Cranium SNB 790 Retruded 750 – 830 ProtrudedMaxilla to Mandible ANB 20 Class I : + 20 to +4.50Class III tendency: +0.50 to +1.50Wits A, B ⊥ Occlusal plane 0 mm Class I : ‐1 to +2
106Cephalometric analysis –Dental Description Measurement Mean Range Interincisal Angle to 1300 Best finish 125 0 – 1300Lower Incisal Inclination to MP 920 Retroclined 890 – 980 ProclinedLower Incisal Protrusion to NB +4mm Retruded +1 to +6 ProtrudedLower Incisal Protrusion to APo +2mm Retruded 0 to +4 ProtrudedUpper Incisal Inclination to SN 1030 Retroclined 990 – 1060 ProclinedUpper Incisal Protrusion to APo 5mm Retruded +2 to +7 ProtrudedUpper Incisal Protrusion to A vertical (to FH)4mm Retruded +2 to +6 Protruded111111111
109Cast analysis by software
110Advantages of computerized analysisAccurateEasyMore information:Arch form Loop distance (Bolton analysis)Determine asymmetric Arch Space analysisRotation Prediction
111DETERMINE THE PROBLEMSKind of problems: Dental problemsSkeletal problemsFacial problemsOcclusal problemsTMJ problemsPeriodontal problemsCausative factorsDegree of problems
112Ackerman and Proffit diagramAligment (spacing and crowding)Profile (convex, straight, concave)Sagittal deviation (Angle class)Vertical deviation (deep bite, open bite)Transsagittal deviation (combine Angle class and cross bite)Sagittovertical deviation (combine Angle class and deep bite or open bite)Verticotransverse deviation (combine cross bite and deep bite or open bite) Transsagittovertical deviation (combine of problems in three planes of space)
114DENTAL PROBLEMSIntra‐arch problemsInter‐arch problemsCausative factorsDegree of the dental problems
115Intra‐arch problemsPosition :Protrusion or retrusion of incisorsMalpositionImpaction RotationAngulationInclination: Procline or reclineSpaces:Spacing or crowdingCurve of Spee
116Inter‐arch problemsMolar relationship Class I, II, IIICanine relationshipClass I, II, IIIVertical relationship: Overbite, deep bite, open bite Horizontal relationship: Overjet, end‐to‐end, anterior crossbite.Posterior crossbiteUpper and lower incisor angulationInter‐arch discrepancyMidline relationship:Midline asymmetry
117Causative factorsSpacingLarge jawSmall teethMissing teethLateral over‐expansion of arches or forward proclination of anterior teeth. CrowdingSmall or constricted archesLarge teethRetroclinationMesial drift of posterior teeth
119Diagnosis of Impacted TeethImpacted Teeth : not erupted for 2 years following the normal eruption age.The eruption path is blocked, or if the eruption stops after the tooth strays to a position labial or lingual to another tooth. The most common impaction: the upper canine. DIAGNOSIS OF AN UPPER IMPACTED CANINEPanoramic x‐ray: Any overlap of the canine crown with the lateral incisor roots → impaction?. Palatal or labial?Palpate the labial tissueOcclusal x‐ray
120Crowding and impacted toothThe "impacted tooth" may be BLOCKED OUT of the arch because of crowding: in a good position but cannot erupt due to a lack of space →blocked out. Evaluate the root formation to determine eruption potential: incomplete root formation → eruption potential. Tx: space is made with open coils or extraction and a deadline # 12 months is set to wait for its eruption.
121Consideration in impacted toothPosition: labial (good) or palatalAngulation: the more vertical the more successSpace available: enough?The path to the correct position?The age: best under 25The risk: AnkylosisDamage the adjacent teeth
122Degree of problems: Diagnostic Parameters1. Canine and molar relationships: RM, RC, LM, LC2. Angle classification 3. Overbite4. Overjet5. Stage of dental development6. Presence of crossbite: with or without functional shift7. Space analysis8. POG interpretation9. CEP interpretation
1231. Canine and molar relationships: RM, RC, LM, LCa. Class Ib. Class II*c. Class III*d. Not fully erupted2. Angle classification a. Class I malocclusion b. Class II malocclusion, division 1, 2 and subdivision*c. Class III malocclusion, subdivision*
1243. Overbitea. Normal (5 % ‐ 20%)b. Moderate deep bite (20% ‐ 50%)c. Severe deep bite ( > 50%)*d. Edge to edge e. Anterior open bite4. Overjeta. Normal (1 – 3mm)b. Excessive ( > 3mm)*c. Edge to edge d. Underjet (negative overjet)
1255. Stage of dental developmenta. Deciduous dentition b. Early Mixed dentitionc. Late Mixed dentitiond. Permanent dentition 6. Presence of cross bite: with or without functional shifta. None b. Anterior c. Posteriord. Both
1267. Space analysisa. Adequate arch length ( +1 to ‐1mm)b. Mild crowding (‐2 to ‐3mm)c. Moderate crowding (‐4 to ‐6mm) or Severe (> ‐6mm)d. Mild spacing (1 – 3mm)e. Moderate spacing (4 to 6mm) or Severe (> 6mm)8. POG interpretationa. Normal b. Abnormal: missing, supernumerary, ectopic, impacted tooth) 9. CEP interpretationa. Normal b. Beyond the normal range: 1 SDc. Beyond the normal range: 2 SDd. Beyond the normal range: 3 SD