title: Simultaneous 3-dimensional Le Fort I/distraction osteogenesis technique: positional changes.
abstract: OBJECTIVE
  This preliminary study assesses the positional changes of the maxilla after simultaneous 3-dimensional Le Fort I osteotomy and distraction osteogenesis (3D-LFI/DO).
  
  
  METHODS
  The records of 18 patients, 17.7 years of age (range, 12-38 years) at the time of surgery, manifesting transverse maxillary deficiencies and variable sagittal/vertical deformities were evaluated presurgically and 3 years postsurgery (range, 1 to 10 years). All patients underwent midsagittal 2-piece Le Fort I osteotomies. The planned sagittal and vertical positional changes were immediately performed by the Le Fort I surgery. After a latency period of 5 to 7 days, maxillary expansion was slowly achieved by distraction osteogenesis using a Hyrax appliance activated 1-mm/day. Once the planned transverse expansion had been attained, the Hyrax device served as a retention appliance for 8 to 12 weeks, after which the distraction gap was orthodontically closed. The morphological changes were assessed by comparing standardized preoperative and postsurgical models, posterior-anterior radiographs, and lateral cephalograms.
  
  
  RESULTS
  Class I canine and molar relationships, along with satisfactory sagittal and vertical skeletal relationships, were observed at follow-up. The maxilla was advanced (1.5-1.8 mm) and positioned either superiorly or inferiorly (1.2-2.9 mm), depending on the original deformity. The arch perimeter increased 5.4 mm and the arch width increased between 4.2 and 6.6 mm. The maxillary expansion was nonparallel, greater anteriorly and inferiorly.
  
  
  CONCLUSIONS
  The 3D-LFI/DO can be used to simultaneously and selectively widen, lengthen and vertically reposition the maxilla, producing acceptable post-treatment skeletal and dental relationships, without healing problems observed clinically.
authors.affiliation: Department of Surgery, Division of Oral and Maxillofacial Surgery, University of Texas Southwestern Medical Center, Dallas, TX, USA.
authors.forename: Lécio P
authors.initials: LP
authors.lastname: Pinto
authors.forename: William H
authors.initials: WH
authors.lastname: Bell
authors.forename: Stephen
authors.initials: S
authors.lastname: Chu
authors.forename: Peter H
authors.initials: PH
authors.lastname: Buschang
mesh_terms: D000293:Adolescent; D000328:Adult; D002508:Cephalometry; D002648:Child; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007574:Jaw Relation Record; D008297:Male; D008310:Malocclusion / Q000601:surgery*; D008437:Maxilla / Q000601:surgery*; D009971:Orthodontics, Corrective / Q000379:methods; D019857:Osteogenesis, Distraction / Q000379:methods*; D019340:Osteotomy, Le Fort / Q000379:methods*; D010155:Palatal Expansion Technique; D016896:Treatment Outcome; D055815:Young Adult