Morphologic characteristics of the dentition and palate in cases of skeletal asymmetry

The purpose of this study was to clarify the three-dimensional morphological characteristics of the dentition and palate in skeletal asymmetry in patients with skeletal Class III malocclusion using a newly defined palatal reference plane in a dental cast. Twenty patients (5 males and 15 females) who had skeletal Class III malocclusion with facial asymmetry were selected. Pretreatment posteroanterior cephalometric radiographs and maxillary dental casts were used. The lateral deviation of Me was measured as the distance from a line perpendicular to Lo-Lo' that passed through CG. The angle between the Lo-Lo' plane and the J-J' plane was measured. Each maxillary dental cast was measured using a three-dimensional surface-scanning system, and the newly defined palatal reference plane was calculated. The right/left difference in the radius of curvature of the palate and right/left differences in the vertical and mesiodistal positions of the first molars were analyzed. Linear correlation and regression techniques were used. Our findings demonstrate that the lateral deviation of the mandible is closely related to the morphology of the alveolar process and to the vertical height of the dentition. In this study, the three-dimensional application of a new palatal reference plane is very useful in morphological research, and the results provide detailed information on the characteristics of facial asymmetry.