title: [Postoperative evaluation in mandibular prognathism treated by bilateral sagittal split osteotomy].
abstract: The present study was undertaken to evaluate the postoperative relapse from the period of unwiring to 1 year postoperatively and its correlation to the amount of mandibular setback and change in vertical dimension after mandibular bilateral sagittal split osteotomy. Twenty-seven patients were evaluated cephalometrically by the time preoperatively, 6 weeks, 6 months and 1 year postoperatively. It was found that 1) the average amount of mandibular setback at pogonion point, 6 weeks postoperatively, is 7.6mm backward and 1.9mm downward, 2) the average amount of horizontal relapse at pogonion point, 6 months and 1 year postoperatively, are 1.9mm and 2.3mm respectively. 86% of the horizontal relapse, 1 year postoperatively, occurs in the first 6 months after removal of intermaxillary fixation, 3) the average amount of vertical relapse at pogonion point, 6 months and 1 year postoperatively, are 0.9mm and 1.1mm upward. 82% of the vertical relapse, 1 year postoperatively, occurs in the first 6 months after removal of intermaxillary fixation, 4) the amount of 1 year postoperatively horizontal relapse is significantly correlated both with the amount of horizontal mandibular set back and vertical downward change (r = 0.58, 0.67, p < 0.001), whereas the amount of vertical relapse is with the vertical downward change only, but horizontal setback isn't.
authors.affiliation: Department of Dentistry and Surgery, Chang Gung Memorial Hospital, Taipei, Taiwan, R.O.C.
authors.forename: J W
authors.initials: JW
authors.lastname: Liou
authors.forename: C S
authors.initials: CS
authors.lastname: Huang
authors.forename: F L
authors.initials: FL
authors.lastname: Wang
authors.forename: Y R
authors.initials: YR
authors.lastname: Chen
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008334:Mandible / Q000601:surgery*; D008875:Middle Aged; D010027:Osteotomy; D011378:Prognathism / Q000601:surgery*; D012008:Recurrence