title: Mandibular setback by sagittal split ramus osteotomy: a 12-year follow-up.
abstract: Short- and long-term skeletal changes after mandibular setback were analyzed using bilateral sagittal split ramus osteotomy. Twelve patients who had undergone mandibular setback surgery between 1986 and 1990 were available for long-term cephalography on average 12 years after primary surgery. The mean amount of surgical setback had been 6.4 mm. After the first postoperative year, there was skeletal relapse of 1 mm at the B-point and pogonion (Pg), amounting to 14% of the initial skeletal setback. In contrast to condylar displacement and proximal segment rotation, osteotomy slippage was associated with positional changes at the B-point and Pg. From 1 to 12 years postoperatively, the B-point and Pg remained stable. Mandibular ramus and corpus length decreased 2.1 mm and 1.3 mm, respectively, indicating remodeling at the osteotomy sites and probably condylar resorption.
authors.affiliation: Department of Cranio-Maxillofacial Surgery, University of Bern, Inselspital, Bern, Switzerland. nicole.eggensperger@insel.ch
authors.forename: Nicole
authors.initials: N
authors.lastname: Eggensperger
authors.forename: Thomas
authors.initials: T
authors.lastname: Raditsch
authors.forename: Farhan
authors.initials: F
authors.lastname: Taghizadeh
authors.forename: Tateyuki
authors.initials: T
authors.lastname: Iizuka
mesh_terms: D000293:Adolescent; D000328:Adult; D001862:Bone Resorption; D002508:Cephalometry; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008313:Malocclusion, Angle Class III / Q000601:surgery*; D008334:Mandible / Q000601:surgery*; D008335:Mandibular Condyle / Q000473:pathology; D008875:Middle Aged; D019647:Oral Surgical Procedures; D010027:Osteotomy; D012008:Recurrence; D018709:Statistics, Nonparametric