title: Condylar and temporomandibular joint disc positions after mandibular osteotomy for prognathism.
abstract: OBJECTIVE
  The purpose of this study was to compare the changes in temporomandibular joint (TMJ) morphology and clinical symptoms after sagittal split ramus osteotomy (SSRO) and intraoral vertical ramus osteotomy (IVRO) with and without a Le Fort I osteotomy.
  
  
  METHODS
  Of 43 patients with a diagnosed jaw deformity, 20 underwent IVRO without internal fixation and 23 underwent SSRO with rigid internal fixation. Some operations were performed in combination with a Le Fort I osteotomy. The TMJ symptoms and joint morphology, including the disc position, were assessed preoperatively and postoperatively using magnetic resonance imaging (MRI) and axial cephalography.
  
  
  RESULTS
  A significant difference in the direction of condylar rotation was seen in horizontal axial cephalography images (P <.01). Fewer or no TMJ symptoms were reported postoperatively by 88% of the patients who underwent IVRO with or without a Le Fort I osteotomy and by 66.7% of patients who underwent SSRO with or without a Le Fort I osteotomy. In sagittal images, no change was seen in anterior disc displacement after SSRO; however, improvement was seen in 44.4% of patients with anterior disc displacement who underwent IVRO with or without a Le Fort I osteotomy.
  
  
  CONCLUSIONS
  These results suggest that SSRO does not improve anterior disc displacement; IVRO improves anterior disc displacement in the initial postsurgical period, and both procedures may improve TMJ symptoms.
authors.affiliation: Received from the Department of Oral and Maxillofacial Surgery, Graduate School of Medicine, Kanazawa University, Kanazawa, Japan.
authors.forename: Koichiro
authors.initials: K
authors.lastname: Ueki
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; D002508:Cephalometry; D016009:Chi-Square Distribution; D005157:Facial Pain / Q000601:surgery; D006801:Humans; D004204:Joint Dislocations / Q000601:surgery; D008279:Magnetic Resonance Imaging; D008313:Malocclusion, Angle Class III / Q000150:complications / Q000601:surgery; D008334:Mandible / Q000002:abnormalities / Q000601:surgery*; D008335:Mandibular Condyle / Q000473:pathology*; D019647:Oral Surgical Procedures / Q000379:methods*; D010027:Osteotomy / Q000379:methods; D011378:Prognathism / Q000150:complications / Q000601:surgery*; D018709:Statistics, Nonparametric; D019224:Temporomandibular Joint Disc / Q000473:pathology*; D013705:Temporomandibular Joint Disorders / Q000150:complications / Q000601:surgery*; D016896:Treatment Outcome