전방개교증을 동반한 Angle씨 제Ⅲ급 부정교합자의 두부방사선 계측학적 연구

Cephalometric analysis of class Ⅲ malocclusion with open-bite

The usual class Ⅲ malocclusion with open bite is a complex musculoskeletal dentofacial deformity, and its accurate appraisal is essential for their successful treatment by combined surgical-orthodontic technique. In an effort to identify the differences in the dental and skeletal components of a sample of adults with Class Ⅲ malocclusion, with and without open bite, 110 subjects, 67 cases had an anterior open bite were evaluated. Considering nature and balance of the individual maxillofacial components, it is more reasonable to measure the deformities by relative proportional values than by absolute quantitative ones. The conclusions are as follows : In Class Ⅲ malocclusion with open bite, the majorities of deformities result from mandibular characteristecs. 1. mandibular plane angle was larger in open bte group. 2. Gonial angle was larger in open bite group. 3. Lower anterior facial height was longer in open bite group. (proportion of O-ANS/ONa was increased.) 4. Proportion of O-B/O-Pog was decreased in open-bite group