Geometric morphometric analysis of midfacial complex in Class III malocclusion

The geometric morphometric analysis, comparing with traditional cephalometric analysis, could provide more information on morphometric variations. Many studies had shown that the Class III malocclusion is linked with the midfacial complex. The purpose of this study is to investigate the morphological difference between the normal occlusion and the Class III malocclusion among Chinese children. One hundred children had been selected for this study and each occlusion has 25 subjects of male and female groups. The results indicated that the midfacial size of the Class III malocclusion was smaller than normal occlusion for both male and female groups and a horizontal reduction was observed at the posterior midfacial region through analysis of size and shape changes and distribution of principal strain Therefore, it could presume that the Class III malocclusion in midfacial deficiency was caused by anteroposterior retardation of upper jaw growth. The anterior midfacial of the Class III malocclusion was detected in size expansion for the male and reduction for the female. The maxillarv incisor alveolus has an evidenced forward deformation for both male and female group. The primary results of this analysis will make guidelines for allied researches so that better understanding of craniofacial development could be obtained.