title: Horizontal changes in the condylar head after sagittal split ramus osteotomy with bent plate fixation.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the horizontal changes in the condylar head with bent plate fixation after sagittal split ramus osteotomy (SSRO) with and without a Le Fort I osteotomy.
  
  
  METHODS
  Of 47 Japanese patients with mandibular prognathism, 24 underwent SSRO and 23 underwent SSRO in combination with a Le Fort I osteotomy. A 3-5-mm gap was made between the proximal and distal segments, and a bent plate was fixed with 4 screws in each side of the mandible. The angle of the condylar long axis, as well as the anteroposterior and mediolateral displacement of the condylar head were assessed preoperatively and postoperatively by computerized tomography (CT).
  
  
  RESULTS
  There was no significant difference in reduction in mandibular length between SSRO alone and SSRO with Le Fort I on the axial view of a 3-dimensional CT. There were no significant differences between pre- and postoperative horizontal changes in the condylar long axis or in the anteroposterior and mediolateral displacement of the condylar head, although the length of the proximal segment in SSRO with Le Fort I osteotomy was significantly shorter than in SSRO alone (P < .05).
  
  
  CONCLUSIONS
  These results suggest that the use of a bent plate for SSRO does not change preoperative angle or position significantly in setback surgery, regardless of the addition of Le Fort I osteotomy.
authors.affiliation: Department of Oral and Maxillofacial Surgery, Graduate School of Medicine, Kanazawa University, Kanazawa, Japan. kueki@med.kanazawa-u.ac.jp
authors.forename: Koichiro
authors.initials: K
authors.lastname: Ueki
authors.forename: Kagan
authors.initials: K
authors.lastname: Degerliyurt
authors.forename: Yukari
authors.initials: Y
authors.lastname: Hashiba
authors.forename: Kohei
authors.initials: K
authors.lastname: Marukawa
authors.forename: Kiyomasa
authors.initials: K
authors.lastname: Nakagawa
authors.forename: Etsuhide
authors.initials: E
authors.lastname: Yamamoto
mesh_terms: D000293:Adolescent; D000328:Adult; D001860:Bone Plates; D002508:Cephalometry; D005260:Female; D006801:Humans; D019248:Jaw Fixation Techniques / Q000295:instrumentation*; D008297:Male; D008334:Mandible / Q000002:abnormalities / Q000601:surgery*; D008335:Mandibular Condyle / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D008953:Models, Anatomic; D019647:Oral Surgical Procedures / Q000379:methods*; D010027:Osteotomy; D019340:Osteotomy, Le Fort; D011378:Prognathism / Q000601:surgery*; D013705:Temporomandibular Joint Disorders / Q000601:surgery; D014057:Tomography, X-Ray Computed; D055815:Young Adult