title: Stability of Le Fort I osteotomy with maxillary advancement: a comparison of combined wire fixation and rigid fixation.
abstract: OBJECTIVE
  This study compares two types of fixation: intraosseous wires, skeletal suspension wiring, and maxillomandibular fixation (combined wire fixation; CWF) with rigid internal fixation (RIF) in patients who underwent Le Fort I osteotomy to correct maxillary hypoplasia.
  
  
  METHODS
  All patients were operated on by the same surgeon using a standard technique, which included bone grafting. The 12 patients in group A were treated with CWF for 4 weeks. Group B was made up of 13 patients who had RIF and training elastics for 4 weeks. Cephalometric analysis using a commercial software package was performed on radiographs that were taken immediately preoperatively (T1), 1 day postoperatively (T2), and at least 1 year postoperatively (T4). The position of the maxilla in relation to the cranial base and Frankfort plane at each time interval was compared.
  
  
  RESULTS
  Postsurgical horizontal change (maxillary position change from T2 to T4) for both groups was in the posterior direction. In group A, six patients had less than 1 mm change, three had 1 to 2 mm change, and three had > 2 mm change. In group B, 10 patients had less than 1 mm change, three had 1 to 2 mm change and 0 had > 2 mm change. Comparison of mean values of groups A and B suggested improved stability with rigid versus wire fixation in the horizontal plane; however, statistical analysis of adjusted mean values showed no significant difference. Vertical changes in maxillary position were also measured from postoperatively to 1 year (T2 to T4). The vertical changes were minimal in those cases of maxillary advancement where no vertical changes were planned; however, there was a statistically significant (P = .0024) improved stability with RIF versus combined wire fixation cases. Comparison of adjusted means showed double the amount of vertical setting 1 year postoperatively in the CWF group.
  
  
  CONCLUSIONS
  Overall, 22 of 25 patients with horizontal maxillary advancement had excellent stability at 1 year. Observed trends suggest that RIF may have improved stability over CWF.
authors.affiliation: Department of Oral and Maxillofacial Surgery, University of Washington School of Dentistry, Seattle 98104.
authors.forename: M
authors.initials: M
authors.lastname: Egbert
authors.forename: B
authors.initials: B
authors.lastname: Hepworth
authors.forename: R
authors.initials: R
authors.lastname: Myall
authors.forename: R
authors.initials: R
authors.lastname: West
mesh_terms: D000328:Adult; D001860:Bone Plates; D016025:Bone Transplantation; D001864:Bone Wires; D002508:Cephalometry; D005260:Female; D006801:Humans; D016268:Internal Fixators; D007569:Jaw Abnormalities / Q000150:complications; D008297:Male; D008313:Malocclusion, Angle Class III / Q000209:etiology / Q000601:surgery*; D008437:Maxilla / Q000002:abnormalities / Q000601:surgery*; D008875:Middle Aged; D010027:Osteotomy / Q000295:instrumentation*; D012008:Recurrence; D016896:Treatment Outcome