MANDIBULAR SKELETAL AND DENTAL ASYMMETRY IN CLASS-II SUBDIVISION MALOCCLUSIONS

Mandibular symmetry was compared between a group of 28 subjects exhibi ting Class II subdivision malocclusions and 30 subjects with Class I m alocclusions who served as the control group. With submentovertex radi ographs, symmetry was assessed by measuring the relative difference in spatial position of mandibular landmarks in both anteroposterior and transverse dimensions as determined by coordinate systems representing the cranial floor, mandible, and mandibular dentition. Only those var iables representing the anteroposterior difference between right and l eft mandibular molar positions showed a statistically significant diff erence between the groups. Whether the position of the mandibular mola rs was measured relative to the cranial floor or within the mandible i tself, the mandibular first molar was located more posteriorly on the Class II side of the subdivision malocclusion within a mandible that e xhibited no other unusual asymmetry.