抄録
The purpose of the present study was to investigate postoperative stability of asymmetric mandible. We performed a cephalometric radiographic evaluation of postoperative stability on 11 patients who had undergone sagittal splitting ramus osteotomy of asymmetric jaw deformities at our clinic from 1989 to 1991.
The results were as follows:
1. Measurements of areas of right and left mandible by cephalometric radiograms, particulary those in the lower portion, were very useful to evaluate the postoperative change of mandibular asymmetry. The ratio of left area/right area in the lower portion of the mandible was turned to nearly 50/50 at one year after operation in 7 patients.
2. Four of 7 patients, who had a difference of over 7mm in setback between right and left of the mandible and had a horizontal movement of over 6mm at the center of both lower central incisors, exhibited less postoperative horizontal stability.
3. Only two of 9 patients, who were given preoperative orthodontic therapy, showed postoperative instability of the mandible.
4. The correlation between postoperative horizontal instability and posteroanterior instability of the mandible was not definitely confirmed.
