1、Operator:Zhou LingSupervisor:Prof.Li Date:2013.6.611534Development of a Problem List The Problem-Oriented approachClinical EvaluationAnalysis of Diagnostic RecordsOrthodontic ClassificationChapter outline22Analysis of Diagnostic RecordsTwo partsCephalometric analysis of dentofacial relationshipsDent
2、al cast analysisto evaluate space excess or deficiency and symmetry within the dental arches3v Symmetryv Space analysisv Estimating of unerupted permanent teethv Tooth size analysisDental cast analysis4Symmetryv Transparent ruled grid placed over dental castv Oriented to the midpalatal raphe v Spot
3、asymmetries in arch form,and tooth position5 Lateral drift of incisors (Crowding,C lost 3 blocked out)SymmetryDrift of posterior teeth（Early loss of E)6Pendulum7v Symmetryv Space analysisv Estimating of unerupted permanent teethv Tooth size analysisDental cast analysis89vDental castv Computer algori
4、thmSpace Analysis10 Measuring arch perimeter from the mesial of one first molar to the other,over the contact points of posterior teeth and incisal edge of anteriors.Step one:Calculation of available space片段法铜丝法11Step two:Calculation of required spaceMeasure the mesiodistal width of each erupted too
5、th from contact point to contact point.12Space Analysis130101 The space available will not change because of growth.0202All the teeth are normal in size0303Correct anteroposterior position of incisors Three assumptions14InteractionProtrusionRetrusionCrowding15v Crowding and protrusion are different
6、aspects of the same phenomenon.vIf there is not enough room to properly align the teeth,the result can be crowding,protrusion,or(most likely)some combination of the two.161718190101 The space available will not change because of growth.0202All the teeth are normal in size0303Correct anteroposterior
7、position of incisors Three assumptions20v In a child with a well-proportioned face,there is little or no tendency for the dentition to be displaced relative to the jaw during growth.vBut the teeth often shift anteriorly or posteriorly in a child with a jaw discrepancy.21220101 The space available wi
8、ll not change because of growth.0202All the teeth are normal in size0303Correct anteroposterior position of incisors Three assumptions23v Symmetryv Space analysisv Estimating of unerupted permanent teethv Tooth size analysisDental cast analysis24 25 Estimating of Unerupted Permanent TeethRadiograghi
9、cPrediction table methodsCombination26Undistorted radiographic image Compensate for enlargementMeasurement of the teeth on radiographs27 True width of primary molarApparent width of primary molarMeasurement of the teeth on radiographs True width of unerupted PremolarApparent width of unerupted premo
10、lar=28v Accuracy is fair to good depending on the quality of the radiographs and their position in the arch.v The technique can be used in maxillary and mandibular arches for all ethnic groups.Measurement of the teeth on radiographs29 Estimating of Unerupted Permanent Teeth RadiograghicPrediction ta
11、ble methodsCombination30Moyers prediction Estimation from proportionality tablesMeasuring the mesiodistal width of the lower incisors Prediction the size of both the lower and upper unerupted canines and premolars31 Estimation from proportionality tables32vNorthern European white childrenvNo radiogr
12、aphs are required,used for the upper or lower arch.Estimation from proportionality tables33 Estimation from proportionality tables34 Estimating of Unerupted Permanent TeethRadiograghicPrediction table methodsCombination35Combination of radiographic and prediction tableIt depends!36Comparison1Radiogr
13、aghic2Most practicalNorthern European white childrenNo radiograghsNo reference table3MoyersTakana&JohnstonNorthern European white childrenNo radiographsDepending on the quality of the radiographs and their position in the archFor all ethnic groups.37v Symmetryv Space analysisv Estimating of unerupte
14、d permanent teethv Tooth size analysisDental cast analysis38v Although the natural teeth match very well in most individuals,approximately 5%of the population have some degree of disproportion among the sizes of individual teeth.-Tooth Size Discrepancy(TSD)Tooth Size Analysis39Tooth Size Analysis40B
15、olton RatioTooth Size Analysis(78.8 1.72)%(91.5 1.51)%41 A quick check for.v Anterior tooth size discrepancy:2 2v Posterior tooth size discrepancy：5=5v A tooth size discrepancy of less than 1.5mm is rarely significant.Tooth Size Analysis42v Symmetryv Space analysisv Estimating of unerupted permanent
16、 teethv Tooth size analysisDental cast analysis43Analysis of Diagnostic RecordsTwo partsCephalometric analysis of dentofacial relationshipsDental cast analysisto evaluate space excess or deficiency and symmetry within the dental arches44 The introduction of radiographic cephalometrics is in 1934 by
17、Hofrath in Germany and Broadbent in USA.Cephalometric analysis45Function v Original purposev Evaluating dentofacial proportions and clarify the anatomic basis for a malocclusion v Observing pathologic changes(Sometimes)Researching on growth patterns in the craniofacial complex.46This patient has fus
18、ion of the 1st and 2nd cervical vertebrae,with the odontoid process extending into the margin of foramen.Function 47Function v Original purposev Evaluating dentofacial proportions and clarify the anatomic basis for a malocclusion v Observing pathologic changes(Sometimes)v Recognizing and evaluating
19、changes brought about by orthodontic treatment.Researching on growth patterns in the craniofacial complex.48Function 49 The goal of cephalometric analysis is to evaluate the relationships,both horizontally and vertically,of the five major functional components of the face.Cephalometric analysis50Cep
20、halometric analysis51vCranial Base S，N，Po，Ba,Bov Maxilla Or，Ptm，ANS，PNS，A，UIv Mandibular Co，Go，B，LI，Pog，Me，GnCephalometric Landmarks52v S.sellav N.nasion v Po.porion v Ba.basion v BoCephalometric Landmarks53v Or.orbitale v Ptm.v ANS.Anterior nasal spine v PNS Posterior nasal spine v A.subspinale v U
21、I.Upper IncisorCephalometric Landmarks54v Co.condylionv Go.gonionv Pog.pogonionv Me.menton v Gn.gnathionv B.supramentalv LI.lower incisor Cephalometric Landmarks5556Two methodsContemporary measurement approachCephalometric analysis via direct comparison with reference templateCephalometric analysis5
22、7Contemporary measurement approachv Choice of a Horizontal(Cranial)Reference Line.v Steiner Analysisv Sassouni Analysisv Wits Analysis58Choice of a Horizontal Reference LineAn international congress was held in Frankfort,Germany in 1882.with the choice of a horizontal reference line for orientation
23、of skulls59“Machine porion :The upper surface of the ear rod of the cephalometric Anatomic porion”:The upper surface of the shadow of the auditory canal.Choice of a Horizontal Reference Line6061NHP(natural head position):Relaxed individuals look at a distant obiect or into their own eyes in a mirror
24、 and incline their heads up and down in increasingly smaller movements until they feel comfortably positioned.Choice of a Horizontal Reference Line62Choice of a Horizontal(Cranial)Reference Line.Steiner AnalysisSassouni AnalysisWits AnalysisContemporary measurement approach63Steiner Analysisv SNA:Ma
25、xilla to the cranial base 82 2 v SNB：Mandible to the CB 78 2v ANB:skeletal jaw discrepancy.v SN-MP(mandiblar plane):Vertical position of the mandible.64ANB angle is influenced by two factors:vVertical height of the face.vAnteroposterior position of nasion.Steiner Analysis6566Steiner Analysisv U1-NA（
26、mm)v U1-NA v L1-NB（mm)v L1-NB67 The balance between the prominence of the chin and the prominence of the lower incisor:the more prominent the chin,the more prominent the incisor can be。Steiner Analysis68Steiner Analysis6970Steiner Analysis71Choice of a Horizontal(Cranial)Reference Line.Steiner Analy
27、sisSassouni AnalysisWits AnalysisContemporary measurement approach72skeletal open bite SN FH PP OP MP Sassouni Analysis7374Choice of a Horizontal(Cranial)Reference Line.Steiner AnalysisSassouni AnalysisWits AnalysisContemporary measurement approach75 Wits analysis（overcome the limitations of ANB as
28、an indicator of jaw discrepancy)It is based on a projection of points A and B to the occlusal plane,along which the linear difference between these points is measured.76occlusal plane（OP）77Female:0Male:-17879v First step:pick the correct template from the set of age-different ones that represent the reference data.v Two things must be kept in mind:(1)the patients physical size (2)his or her developmental age80SCranial base superimpositionMaximum contour of the maxilla Symphysis of themandible81828384Thank you!85谢谢 谢！谢！放映结束 感谢各位的批评指导！让我们共同进步86
