Abstract
Purpose: The purpose of this study was to evaluate post-surgical skeletal stability in patients with facial asymmetry and canted occlusal plane.
Methods: The subjects were 7 patients who underwent bilateral sagittal splitting mandibular ramus osteotomy and Le Fort I osteotomy. Pre- and post-surgical skeletal changes were measured by frontal cephalogram. Bone fixation with mini-plates and maxillomandibular traction with elastic bands after surgery were performed. Radiographs were taken on the initial, pre-surgical and 2nd day, and then 1, 3, 6, 12 and over 24 months after the surgery.
Results: On the 2nd day after the surgery, the canted occlusal plane was horizontal in all of the subjects. At 6 months after the surgery, 4 of 7 cases had stabilized but 3 cases had slightly relapsed. Laterality of the lateral angle of the mandibular ramus had stabilized at 6 months after surgery. The ratio of the right and left vertical distances between the X-axis and neck point on the buccal surface of the maxillary first molar approached 1.0 in all of the subjects. On the 2nd day after the surgery, but relapsed later. At 6 months after the surgery, the ratio had stabilized. Over 2 years after the surgery, the distance from the Y-axis to the upper and lower central incisor's midline had stabilized.
Conclusion: These results suggested that in patients having facial asymmetry with canted occlusal plane and undergoing bilateral sagittal splitting mandibular ramus osteotomy and Le Fort I osteotomy, there is some possibility of relapse in the first 6 months after surgery.
