Clinical Statistical Analysis of Treatment for Jaw Deformities in the Section of Maxillofacial Orthognathics, Department of Orthodontics, Tokyo Medical and Dental University Dental School Hospital, during the Past 30 Years

Abstract

The present study conducted a statistical survey of 1118 patients with jaw deformity who underwent surgical orthodontic treatment in the Section of Maxillofacial Orthognathics, Department of Orthodontics, Tokyo Medical and Dental University from 1980 to 2009.
The results were as follows:
1. There were 442 male and 676 female patients (ratio 1:1.5).
2. The mean age at operation of all patients was 24.2 years old. The mean age has tended to increase in recent years.
3. The most common condition was mandibular prognathism without other deformities of the jaw, accounting for 47.3% of the patients. Next was mandibular prognathism with asymmetry, accounting for 20.4%, and then mandibular prognathism with open bite, accounting for 14.1%.
4. The most frequently used surgical procedure was sagittal split ramus osteotomy (SSRO), accounting for 64.0%. The combination of Le Fort I osteotomy and SSRO accounted for 21.0%.
5. For bone fixation after SSRO, wire fixation, which used to be the most common method, has been almost completely replaced by screw or mini-plate fixation in recent years.