classification of Malocclusion /certified fixed orthodontic courses by Indian dental academy
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The document discusses the classification of malocclusion in orthodontics, emphasizing the importance of categorizing deviations from normal occlusion to facilitate diagnosis and treatment planning. It covers different types of malocclusions, including intra-arch and inter-arch classifications, as well as various systems of classification such as Angle’s, Lischer’s, and Simon’s. The content highlights the complexities of malocclusion and the necessity for a common language among practitioners for effective communication.
classification of Malocclusion /certified fixed orthodontic courses by Indian dental academy
- 2. INDIAN DENTAL ACADEMY Leader in continuing dental education www.indiandentalacademy.com www.indiandentalacademy.com
- 3. Introduction Normality is the basis of classification in orthodontics. It rests on what is known as biologic continuity, i.e., the most frequently found relationship of the teeth and of the bones of the face in relation to each other and to the skull as a whole. Malocclusion is any perversion of normal occlusion of the teeth. It is a condition where there is departure from the normal relation of the teeth to other teeth in the same arch and to the teeth in the opposing arch. www.indiandentalacademy.com
- 4. INTR ODUCTIO N In order to acquire a better understanding of the many deviations from normal occlusion and to assist in diagnosis and treatment planning, it becomes necessary to group the varieties of malocclusion into order. This is difficult as occlusal anomalies are many and varied. Orthodontics has been described, admirably, as a ‘Science of Infinite Variations’. www.indiandentalacademy.com
- 5. DEFINITION Classification is a process of analyzing cases of malocclusion for the purpose of segregating them into a small number of groups, which groups are characterized by certain specific and fundamental variations from normal occlusion of the teeth. www.indiandentalacademy.com
- 6. OB JECTIVES Classification is an essential communication tool between dental school professor and student, between practitioners, and between practitioner and insurance company or government bureaucracy. It is essential that everyone "speak the same language." Classification aids in the diagnosis and treatment planning of malocclusions by orienting the clinician to the type and the magnitude of the problems and possible mechanical solutions to the problems. www.indiandentalacademy.com
- 7. OB JECTIVES Segregation of the countless number of cases of tooth malposition into a comparatively low number of groups, each group containing only such cases as are characterized by a common factor or factors of fundamental significance. Ease of reference i.e. giving name to a group of symptoms making together a single problem Comparison of cases with other cases having same problem www.indiandentalacademy.com
- 8. GENER AL CLASSIFICATIO N Malocclusion can be broadly divided into Individual tooth malposition or Intra arch malocclusion Maxillo-mandibular malocclusions or Inter arch malocclusion www.indiandentalacademy.com
- 9. GENER AL CLASSIFICATIO N Individual tooth malposition or Intra arch malocclusion A tooth can be abnormally related to its neighboring teeth, such abnormal variations are called individual tooth malpositions or intra arch malpositions. Some of the commonly seen individual tooth malpositions are Distal inclination or distal tipping Mesial inclination or mesial tipping Lingual inclination or lingual tipping Buccal inclination or buccal tipping www.indiandentalacademy.com
- 10. GENER AL CLASSIFICATIO N Individual tooth malposition or Intra arch malocclusion Mesial displacement Distal displacement Lingual displacement Buccal displacement Infraversion or infraocclusion Supraversion or supra occlusion Disto lingual or mesio buccal rotation Mesio lingual or disto buccal rotation Transposition www.indiandentalacademy.com
- 13. GENER AL CLASSIFICATIO N Inter arch malocclusions These malocclusions are characterized by abnormal relationships between two teeth or groups of teeth of one arch to the other arch. These inter arch malocclusion can occur in Sagital plane Vertical plane Transverse plane www.indiandentalacademy.com
- 14. GENER AL CLASSIFICATIO N Sagital plane malocclusions Pre-normal occlusion- refers to a condition where the lower arch is more forwardly placed when the patient bites in centric occlusion. Post-normal occlusion- a condition where the lower arch is more distally placed when the patient bites in centric occlusion. www.indiandentalacademy.com
- 15. GENER AL CLASSIFICATIO N Vertical plane malocclusions Deep bite or increased over bite: this refers to a condition where there is an excessive vertical overlap between upper and lower anterior teeth. Open bite: is a condition where there is no vertical overlap between upper and lower teeth . Thus a space exist between the upper and lower teeth when the patient bites in centric occlusion. Open bite can be in anterior or posterior region. www.indiandentalacademy.com
- 16. GENER AL CLASSIFICATIO N Transverse plane malocclusions Cross bite – refers to a condition in which mandibular teeth overlap their maxillary antagonists. Cross bite can be anterior or posterior Buccal Non occlusion – refers to a condition in which maxillary posteriors are completely buccally placed in relation to mandibular antagonists without occluding Palatal Non occlusion – refers to a condition in which maxillary posteriors are completely palatally placed in relation to mandibular antagonists without occluding www.indiandentalacademy.com
- 17. ANGLE’S CLASSIFICATIO N Angle believed that since biologic entities as well as inanimate elements can be arranged into well-defined classes, the same held also of the occlusion of the teeth and the shape of the face. Angle based his classification of malocclusion on the normal mesiodistal relations of the mesiobuccal cusps of the upper first molars in relation to the mandibular first molars. www.indiandentalacademy.com
- 18. ANGLE’S CLASSIFICATIO N Basis for Angle’s classification Most indicative irregularity of teeth found in antero-posterior relationship of the teeth and the jaws. There is a normal mesio distal or antero-posterior position for the body of the mandible with its superimposed mandibular dental arch to occupy in the anatomy of the skull. The maxillary dental arch being built upon a base that is a fixed section of the skull anatomy, is more or less stable in its relationship to various landmarks on the head and consequently the first molar teeth in this arch may be quite safely selected as a key tooth from which to judge the relationship of mandibular dental arch and intern to the body of mandible upon which it is located www.indiandentalacademy.com
- 19. ANGLE’S CLASSIFICATIO N Basis for Angle’s classification If there is shifting of maxillary molars in their relationship to the skull anatomy, this variation can be detected by changes in the axial inclination of teeth in the maxillary arch. The axial change is especially manifested by canine teeth. Curvature and line of occlusion is unique to each individual. www.indiandentalacademy.com
- 20. ANGLE’S CLASSIFICATIO N Angle used the Roman numerals I, II and III to designate the three main classes of mesiodistal arch relationship viz., Class I or normal, Class II or distal and Class III or mesial relationship of the cusps of the mandibular first molars to the maxillary first molars. He employed the Arabic numerals 1 and 2 to denote divisions of the classifications. Unilateral deviations he termed subdivisions. www.indiandentalacademy.com
- 21. ANGLE’S CLASSIFICATIO N Angle classified malocclusion as follows Class I Class II Division 1 Division II Subdivision Class III Subdivision www.indiandentalacademy.com
- 22. ANGLE’S CLASSIFICATIO N Class I Malocclusion The mandibular dental arch and the body of the mandible are in normal relation to the maxillary arch indicated by the fact that mesiobuccal cusp of the maxillary first permanent molar occludes in the buccal groove of the mandibular permanent first molar and the mesiolingual cusp of the maxillary first molar occludes with the occlusal fossa of the mandibular first permanent molar when the jaws are in centric occlusion www.indiandentalacademy.com
- 24. ANGLE’S CLASSIFICATIO N Class II Malocclusion The mandibular dental arch and the body of the mandible are in distal relation to the maxillary arch by half the width of the maxillary first permanent molar or mesioodistal width of a premolar indicated by the fact that mesiobuccal cusp of the maxillary first permanent molar occludes in the space between the mesiobuccal cusp of the mandibular permanent first molar and the buccal cusp of the second premolar. www.indiandentalacademy.com
- 25. ANGLE’S CLASSIFICATIO N Class II Malocclusion The mesiolingual cusp of the maxillary first molar occludes mesial to the mesiolingual cusp of the mandibular first permanent molar when the jaws are in centric occlusion. www.indiandentalacademy.com
- 27. ANGLE’S CLASSIFICATIO N Class II Malocclusion Division I A class II malocclusion in which maxilary incisors are in labioversion Subdivision A class II division I malocclusion occuring on only one side www.indiandentalacademy.com
- 28. ANGLE’S CLASSIFICATIO N Class II Malocclusion Division II A class II malocclusion in which maxilary incisors are not in labioversion rather they are retroclined with laterals overlapping centrals or canines overlapping laterals Subdivision A class II division I malocclusion occuring on only one side www.indiandentalacademy.com
- 29. ANGLE’S CLASSIFICATIO N Class III Malocclusion The mandibular dental arch and the body of the mandible are in mesial relationship to the maxillary arch indicated by the fact that mesiobuccal cusp of the maxillary first permanent molar occludes in the interdental space between the distal aspect of the distal cusp of the mandibular first permanent molar and the mesial aspect of the mesial cusp of the second permanent molar www.indiandentalacademy.com
- 31. ANGLE’S CLASSIFICATIO N Class III Malocclusion Subdivision A class III malocclusion in which malocclusion is only unilaterally www.indiandentalacademy.com
- 32. ANGLE’S CLASSIFICATIO N Pseudo-Class III Malocclusion In this condition the mandible is protruded a little during the final stages of closure in order to avoid a premature contact of incisors or canines This is most likely to arise in cases where the relationship of the incisors is edge-to-edge, and may be caused by a mildly prenormal relationship of the dental bases Such pseudo – or postural Class III cases may tend, if left untreated, to become established by a further development of the whole occlusion in Class III relation. www.indiandentalacademy.com
- 33. Differences between true and pseudo class III malocclusion Features True Class III Pseudo Class III 1 Profile Concave Straight to concave 2 Etiology Hereditary Habitual/developmental 3 Premature contacts Absent Present 4 Path of closure Forward Deviated 5 Gonial angle Increased/decreased Normal 6 Retrusion of mandible further Not possible Possible 7 Treatment Orthopedic or surgical 8 Left untreated No further changes Elimination of prematurities, replacement of lost posterior teeth Becomes established into true class III www.indiandentalacademy.com
- 34. ANGLE’S CLASSIFICATIO N Drawbacks of Angle’s Classification The Angle classification was readily accepted by the dental profession, since it brought order out of what previously had been confusion regarding dental relationships. It was recognized almost immediately, however, that there were deficiencies in the Angle system. www.indiandentalacademy.com
- 35. ANGLE’S CLASSIFICATIO N Drawbacks of Angle’s Classification Angle considered malocclusion only in antero-posterior plane Angle considered maxillary first permanent molar as a fixed point but it was not found so The classification cannot be applied if first permanent molars are missing or extracted The classification cannot be applied in the deciduous dentition www.indiandentalacademy.com
- 36. ANGLE’S CLASSIFICATIO N Drawbacks of Angle’s Classification The classification does not differentiates between skeletal and dental malocclusions The classification does not highlight the etiology of the malocclusion Individual tooth malpositions have not been considered in the classification www.indiandentalacademy.com
- 37. LISCHER ’S CLASSIFICATIO N Lischer introduced the following terms which are widely used to describe the varieties of malocclusion. He substituted the term Class I, Class II, Class III given by angle with the terms Neurtro-occlusion, Disto-occlusion and Mesio-occlusion. www.indiandentalacademy.com
- 38. LISCHER ’S CLASSIFICATIO N Neutro-occlusion: Normal relation of dental arches. It is synonymous with Angle’s Class I malocclusion. Disto-occlusion: Synonymous with Angle’s Class II, used to describe all cases of post-normal occlusion. Mesio-occlusion: Synonymous with Angle’s Class III and describes all cases of prenormal occlusion. www.indiandentalacademy.com
- 39. LISCHER ’S CLASSIFICATIO N He gave the suffix “version” to describe the He gave the suffix “version” to describe the wrong position of individual teeth as follows: Linguo version—Lingual placement Labio version—Labial placement Mesio version—Mesial placement Disto version—Distal placement Infra version—Intrusion of teeth Supra version—Extrusion of teeth Torsiversion—Rotation Perversion—Impacted tooth www.indiandentalacademy.com
- 40. Dewey’s Modif ication of Angle’s Classif ication Dewey proposed a modification of the Angle’s classification of malocclusion. He divided the Angle’s class I into five types and Angle’s Class III into three types. There were no modifications for Class II. He considered the same molar relationship as in Angle’s classification www.indiandentalacademy.com
- 41. Dewey’s Modif ication of Angle’s Classif ication Modification of Angle’s Class I Type 1. Bunched or crowded maxillary anterior teeth. The canines may be in labioversion or infraversion. All other versions of individual teeth may be present Type 2. Maxillary incisors in labioversion Type 3. The maxillary incisor teeth are in linguoversion to the mandibular incisors Type 4. The molars, occasionally also premolars are in linuoversion or labiobversion but canines and incisors are in normal relation Type 5. The molars are in mesioversion due to shifting following loss of teeth anterior to molars www.indiandentalacademy.com
- 42. Dewey’s Modif ication of Angle’s Classif ication Modification of Angle’s Class III Type 1. The dental arches are well formed and the teeth are in normal alignment when viewed individually but there is edge-to-edge bite in anterior region Type 2. The mandibular incisors are crowded and in lingual relation to the maxillary incisors Type 3. The maxillary arch is underdeveloped. The maxillary incisor are crowded. The mandibular arch is well developed and the mandibular teeth are in normal aligment www.indiandentalacademy.com
- 43. B ENNET’S CLASSIFICATIO N Sir Norman Bennett introduced a classification of abnormalities of occlusion which was based on their etiology. Briefly the classification is as follows: Class I - Abnormal position of one or more teeth due to local causes. Class II - Abnormal formation of a part or whole of either arch due to developmental defects of bone. Class III- Abnormal relationship between upper and lower arches, and between either arch and facial contour and correlated abnormal formation of either arch. www.indiandentalacademy.com
- 44. SIMON’S CLASSIFICATIO N Since growth of the face and jaws occurs in the three planes of space-height, width and depth, abnormalities also occur in any one or more of the foregoing planes. Simon’s craniometric classification relates the denture to the face and cranium in the three planes of space, (1) The Frankfort horizontal (2) The Orbital plane and (3) The raphe or median sagittal plane. www.indiandentalacademy.com
- 45. SIMON’S CLASSIFICATIO N The Frankfort horizontal plane The Frankfort horizontal plane or the eye-ear plane is determined by drawing a straight line through the margin of the bony orbit directly under the pupil of the eye, to the upper margin of the auditory meatus (the notch above the tragus of the ear). This plane is used to determine deviations in the height of the dental arches and teeth in relation to the face and cranium. www.indiandentalacademy.com
- 46. SIMON’S CLASSIFICATIO N The Frankfort horizontal plane www.indiandentalacademy.com
- 47. SIMON’S CLASSIFICATIO N The Orbital plane The orbital plane is a perpendicular at right angles to the eye-ear plane at the margin of the bony orbit directly under the pupil of the eye. This plane is used to determine sagittal deviations of the dental arches and the axial inclination of the teeth to the face and the cranium. www.indiandentalacademy.com
- 49. SIMON’S CLASSIFICATIO N The Raphe or Median Sagittal plane The Raphe or Median Sagittal plane is determined by points approximately 1.5 cm apart on the median raphe of the palate. The raphe median plane passes through these two points at right angles to the Frankfort horizontal plane. This plane is used to determine the deviations in the general form and width of the dental arches and the axial inclination of the teeth in relation to the midline of the palate and the head www.indiandentalacademy.com
- 50. SIMON’S CLASSIFICATIO N The Raphe or Median Sagittal plane www.indiandentalacademy.com
- 51. SIMON’S CLASSIFICATIO N The Law of the Canine In normal arch relationship, according to Simon, the orbital plane passes through the distal axial aspect of the canine. This is known as “The law of the canine”. www.indiandentalacademy.com
- 52. SIMON’S CLASSIFICATIO N Deviation from the raphe or median sagittal plane . Arch form and inclination of tooth axis are determined from this plane. Contraction: A part or all of the dental arch is contracted toward the raphe median plane. The abnormality may be mandibular, alveolar, dental, anterior, posterior, unilateral or bilateral. Distraction: A part or all of the dental arch is wider than usual from the raphe median plane www.indiandentalacademy.com
- 53. SIMON’S CLASSIFICATIO N Deviations from the Frankfort horizontal plane: The angle between the Frankfort horizontal and the occlusal plane, the form of the occlusal curve, and the inclination of the teeth axes are determined from this plane. Attraction: The distance between the occlusal plane and the FH Plane is comparatively shorter than normal. This distance is as a rule normally shorter in the young than in older persons and in some ethnic groups. Abstraction: The distance between the occlusal plane and the FH plane is comparatively longer than normal. www.indiandentalacademy.com
- 54. SIMON’S CLASSIFICATIO N Deviations from the Orbital plane: Sagittal symmetry and inclination of the axes of the teeth are determined from this plane. Protraction: The teeth, one or both dental arches, and or jaws are too far forward. Normally the orbital plane passes through the distal incline of the canine. Retraction: The teeth, one or both dental arches and or jaws are too far retruded. The orbital plane passes too far anteriorly to the canines. www.indiandentalacademy.com
- 55. SIMON’S CLASSIFICATIO N Deviations of the dental arches in relation to the orbital plane, according to Simon, may occur as follows: Both the jaws in normal relation to each other Upper jaw normal, lower jaw distal Upper jaw normal, lower jaw mesial Lower jaw normal, upper jaw mesial Lower jaw normal, upper jaw distal Upper jaw mesial, lower jaw distal Upper jaw distal, lower jaw mesial www.indiandentalacademy.com
- 56. SK ELETAL CLASSIFICATIO N Malocclusion may or may not be associated with facial dysplasia. Dental malocclusion may be present in an otherwise orthognathic face. However, normal occlusion may also be present in a face which is not orthognathic. Facial skeletal patterns are divided into Class 1, in which the profile is orthognathic, Class 2, where the mandible is retrognathic, and Class 3, in which the mandible is prognathic. www.indiandentalacademy.com
- 57. SK ELETAL CLASSIFICATIO N Classification of the facial skeletal pattern takes into consideration also the relationship of the teeth as follows: Skeletal Class 1: The bones of the face and the jaws are in harmony with one another and with the rest of the head. The maxilla is slightly ahead of the mandible. The profile is orthognathic. Division 1. Local malrelations of incisor, canine or premolar teeth. Division 2. Maxillary incisor protrusion. Division 3. Maxillary incisors in linguoversion. Division 4. Bimaxillary protrusion. www.indiandentalacademy.com
- 58. SK ELETAL CLASSIFICATIO N Skeletal Class 2: Subnormal distal mandibular development in relation to the maxilla. Division 1. Maxillary dental arch is narrower than mandibular and there is crowding in the canine region, crossbite and reduced vertical height. Protrusion of the maxillary anterior teeth. The profile is retrognathic. Division 2. Lingual inclination of the maxillary incisors. The lateral incisors may be normal or in labioversion. www.indiandentalacademy.com
- 59. SK ELETAL CLASSIFICATIO N Skeletal Class 3: Overgrowth of the mandible and obtuse mandibular angle. The profile is prognathic at the mandible. www.indiandentalacademy.com
- 60. ACK MAN – ER P OFFIT R CLASSIFICATION Ackerman and Proffit proposed a classification scheme for malocclusions in which five characteristics and their interrelationships are assessed. This system is a synthesis of two schemes, the Angle classification and the Venn diagram, both of which were proposed late in the nineteenth century by Angle and Venn. Venn proposed this representation in 1880, and it has become prominent in symbolic logic for computer use. www.indiandentalacademy.com
- 61. GROUP 1 GROUP 2 GROUP 4 GROUP 3 TRANSVERSE DEVIATION Gp6 Cross bites TRANSBuccal Palatal Unilateral Bilateral Class I Class II Div1 Class II Div 2 Class III SAGITTAL Skeletal Dental SAGITTAL DEVIATION Gp9 TRANSSAGITOVERTICAL VERTICOTRANSVERSE Gp8 PROFILE Skeletal Dental SAGITOVERTICAL Gp7 GROUP 5 VERTICAL DEVIATION Open Bite anterior Open bite posterior Deep bite anterior Collapsed bite posterior INTRA ARCH ALIGNMENT Skeletal Dental www.indiandentalacademy.com Anterior divergent Posterior divergent Convex Concave Straight IDEAL CROWDING SPACING
- 62. ACK MAN – ER P OFFIT R CLASSIFICATION Classification by groups Common to all dentitions is the degree of alignment and symmetry of the teeth within the dental arches. This is represented as the universe (Group 1). Many malocclusions affect the profile. For this reason, profile is represented as a major set (Group 2) within the universe. Lateral (transverse), anteroposterior (sagittal), and vertical deviations and their interrelationships (Groups 3 to 9) are represented by three interlocking subsets within the profile set. www.indiandentalacademy.com
- 63. ACK MAN – ER P OFFIT R CLASSIFICATION Step 1 in the classification procedure is an analysis of the alignment and symmetry of the teeth in the dental arches (interproximal contact relationships). Alignment is the key word of Group 1; among the possibilities are ideal, crowding (arch-length deficiency), spacing, and mutilated. Irregularities of individual teeth are described, if desired, by the method of Lischer, namely, the use of the suffix -version to describe the direction of individual tooth malalignments. Ideal occlusion, plus many (but by no means all) Angle Class I malocclusions, would fall into Group 1. www.indiandentalacademy.com
- 64. ACK MAN – ER P OFFIT R CLASSIFICATION In Step 2 one views the patient's profile. In the profile view, it should be noted whether the face is anteriorly divergent (mandible prominent) or posteriorly divergent (mandible recessive) and whether the lips are convex (prominent), straight, or concave relative to the nose and chin. The "divergence" is most often related to the facial skeleton; lip position is strongly influenced by the teeth. Lip and mouth posture should also be considered in the evaluation. www.indiandentalacademy.com
- 65. ACK MAN – ER P OFFIT R CLASSIFICATION In Step 3 the dental arches are viewed with regard to lateral dimensions (transverse plane), and the buccolingual relationships of the posterior teeth are noted. The term type is used to describe the various kinds of crossbite. A judgment is also made as to whether the problem is basically dentoalveolar or skeletal or due to a combination of the two. Buccal and palatal cross bites ( unilateral or bilateral) comes under this category www.indiandentalacademy.com
- 66. ACK MAN – ER P OFFIT R CLASSIFICATION In Step 4 the patient and dental arches are viewed in the anteroposterior dimension (sagittal plane). In this dimension, the Angle classification system is utilized and is merely supplemented by stating whether a deviation is skeletal, dentoalveolar, or a combination. This information can be derived from observing the patient or more accurately from a cephalometric head film. www.indiandentalacademy.com
- 67. ACK MAN – ER P OFFIT R CLASSIFICATION In Step 5 the patient and the dentition are viewed with regard to the vertical dimension. Bite depth is used to describe the vertical relationships. The possibilities are anterior open-bite, anterior deep-bite, posterior open-bite, or posterior collapsed bite. To determine whether this is on a skeletal, dentoalveolar, or combined basis, a cephalometric analysis may be particularly helpful. www.indiandentalacademy.com
- 68. ACK MAN – ER P OFFIT R CLASSIFICATION This approach defines nine groups of malocclusions. The complexity of the orthodontic problem increases with the group number. Thus, a Group 9 malocclusion is the most complex in that there is an alignment problem, a problem in profile, and problems in the lateral, vertical, and anteroposterior dimensions as well. www.indiandentalacademy.com
- 69. ACK MAN – ER P OFFIT R CLASSIFICATION Advantages of this classification This method of classification based on five descriptive characteristics and defining nine groups of malocclusions overcomes the major weaknesses of the Angle system Specifically, arch-length problems, with or without an influence on the profile, are recognized; the influence of the dentition on the profile is taken into account All three planes of space, not just the sagittal plane, are taken into consideration The differentiation between dental and skeletal problems is made at the appropriate level Diagnosis is inherent in the classification www.indiandentalacademy.com
- 70. ETIOLOGIC CLASSIFICATIO N According to Moyers, Classification of malocclusion can be based on the origin of the problem. There are four classes depending on origin Skeletal or Osseous Dental Muscular Combination of above www.indiandentalacademy.com
- 71. CONCLUSION The goal of modern orthodontics can be summed up as the creation of the best possible occlusal relationships within the framework of acceptable facial aesthetics and stability of the occlusal result. The classification systems aid in diagnosis and treatment planning of malocclusions. There is a basic need for a system of classification of malocclusion that would be adequate for clinical, semantic and public health purpose and could be universally employed by those practicing the specialty throughout the world www.indiandentalacademy.com
- 72. Thank you www.indiandentalacademy.com Leader in continuing dental education www.indiandentalacademy.com