A classification and characterization of skeletal Class III malocclusion on etio-pathogenic basis

Skeletal Class III malocclusion has been classified by the position of the maxilla, the mandible, the maxillary alveolus, the mandibular alveolus and vertical development. This morphologic approach is simple and useful for cl inical use, but it is insufficient to permit understanding of the pathophys iology of dysmorphoses. The authors hypothesized that there were different patterns of mutual relat ion of the skeletal components contributed to pathologic equilibrium of ske letal Class III malocclusion. The purpose of this study is 3-fold; (1) to c lassify skeletal Class III malocclusion in subgroups that can show the arch itectural characteristics of the deformity, (2) to analyze the craniofacial architecture of each subgroup on etio-pathogenic basis, and (3) to charact erize and visualize the pattern as a prototype. Materials used in this stud y were lateral cephalograms of 106 untreated skeletal Class III malocclusio n adults, which were analyzed with modified Delaire's analysis. Linear and angular measurements of each subject were obtained and cluster analysis was used for grouping. In the results, seven groups were identified and presen ted as prototypes, which could show the etio-pathology of the skeletal arch itecture. The classification and description presented in this study is tho ught to be biologic and helpful in the understanding of skeletal Class III malocclusion and treatment planning.