Simultaneous Orthognathic Surgery and Mandibular Contour Osteoplasty for Treating Mandibular Protrusion With High Gonial Angle.

Objective: The purpose of this study was to confirm the effectiveness and feasibility of simultaneous orthognathic surgery and mandibular contour osteoplasty with the help of the accurate surgical templates to treat mandibular protrusion with high gonial angle.
Methods: Ten patients diagnosed as mandibular protrusion with high gonial angle were included in this study. Besides the traditional orthognathic surgery, mandibular contour osteoplasty was performed simultaneously. Models of the mandible were fabricated via 3D printing technology. Accurate surgical templates were produced on the 3D printing model according to preoperative design. Radiographs and medical photographs preoperatively and postoperatively were taken to compare the effectiveness of the operation. Measurement items include gonial angle (Ar-Go-Me), midlines of maxilla and mandible. The clinical manifestation of the temporomandibular joint and condylar process were observed.
Results: Radiographs and photographs of the face were taken after surgery showed satisfactory esthetic outcomes. The right gonial angle improved from 128.20° ± 5.67° to 120.35° ± 0.46°, and the left gonial angle improved from 129.91° ± 2.78° to 120.74° ± 0.59°. The midlines of the maxilla and mandibular basically consisted of the facial midline. After surgery, patients' clinical manifestation of the temporomandibular joint was no significant difference compared with the preoperative and the condylar process had no absorption.
Conclusion: The results of this study showed it was possible to perform orthognathic surgery and mandibular contour osteoplasty simultaneously with the help of surgical templates in the treatment of mandibular protrusion with high gonial angle.