Skeletal Stability after Le Fort I Osteotomy in the Cleft Patients; Preliminary Report

구순구개열 환자의 Le Fort I 골절단술 후 상악골의 위치적 안정성에 관한 연구 ; 예비보고

It is well known that the postoperative skeletal instability after Le Fort I osteotomy for advancement of maxilla in the cleft patients is one of the major surgical problems. So we had tried to compare the amount of relapse after Le Fort I advancement surgery in the horizontal and vertical positional change, angular change of reference points between cleft patients and non-cleft patients. Longitudinal records of 10 consecutive cleft patients (test group) and 20 non-cleft patients (control group) were analyzed. Lateral cephalograms were taken preoperatively, immediately postoperatively, and 2, 6, 12 months postoperatively. We measured horizontal and vertical changes (ANS, PNS, AI) and angular change (SNA) of the reference points and lines. In the test group, horizontal relapse of ANS, PNS, AI point are 36.4%, 37.5%, 32.0% respectively at 12 months postoperatively. The vertical relapse of ANS, PNS, AI are 25.3%, 32.3%, 39.1% respectively at 12 months postoperatively. The angular change of SNA is 33.6% at 12 months postoperatively. In the control group, horizontal relapse of ANS, PNS, AI point are 23.8%, 30.2%, 21.7% respectively at 12 months postoperatively. The vertical relapse of ANS, PNS, AI are 22.7%, 27.3%, 25.1% respectively at 12 months postoperatively. The angular change of SNA is 22.2% at 12 months postoperatively. The cleft patients have a larger tendency of skeletal and dental relapse compared with non-cleft patients after Le Fort I surgery. So the oral and maxillofacial surgeons must keep in mind these facts in order to minimize the relapse phenomenon from the beginning of surgical planning to postoperative care.