Evaluation of masticatory function after sagittal split ramus osteotomy for patients with mandibular prognathism.

The aim of this study was to measure the changes in masticatory function for 1 year after sagittal split ramus osteotomy. Thirty prognathic patients who underwent preoperative and postoperative orthodontic treatment participated in this study. Their masticatory performance, occlusal contact area and points, and biting force were measured before surgery and 3, 6, and 12 months postoperatively. From 3 months after surgery, masticatory efficiency was greater than that found preoperatively, and the increase was significant 6 months after surgery. Occlusal contact area and points tended to increase from 3 months after surgery, and there was a significant increase 12 months after surgery. The bilateral biting force was lower 3 months after surgery than it was preoperatively, but it had increased significantly and was balanced on left and right sides 12 months after surgery.