title: Factors related to stability following the surgical correction of skeletal open bite.
abstract: OBJECTIVE
  If a skeletal anterior open bite malocclusion is treated by orthognathic surgery directed only at the mandible, the lower jaw is repositioned upward in a counter-clockwise rotation. However, this procedure has a high risk of relapse. In the present study, the key factors associated with post-surgical stability of corrected skeletal anterior open bite malocclusions were investigated.
  
  
  METHODS
  Eighteen orthognathic patients were subjected to cephalometric analysis to assess the dental and skeletal changes following mandibular surgery for the correction of an anterior open bite. The patients were divided into two groups, determined by an increase or decrease in nasion-menton (N-Me) distance as a consequence of surgery. Changes in overbite, the displacements of molars and positional changes in Menton were evaluated immediately before and after surgery and after a minimum of one year post-operatively.
  
  
  RESULTS
  The group with a decreased N-Me distance exhibited a significantly greater backward positioning of the mandible. The group with an increased N-Me distance experienced significantly greater dentoalveolar extrusion of the lower molars.
  
  
  CONCLUSIONS
  A sufficient mandibular backward repositioning is an effective technique in the prevention of open bite relapse. In addition, it is important not to induce molar extrusion during post-surgical orthodontic treatment to preserve stability of the surgical open bite correction.
authors: Goshi
authors: G
authors: Ito
authors: Myongsun
authors: M
authors: Koh
authors: Tadashi
authors: T
authors: Fujita
authors: Maya
authors: M
authors: Shirakura
authors: Hiroshi
authors: H
authors: Ueda
authors: Kazuo
authors: K
authors: Tanne
mesh_terms: D002508:Cephalometry / Q000379:methods; D002680:Chin / Q000473:pathology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008312:Malocclusion, Angle Class II / Q000601:surgery; D008313:Malocclusion, Angle Class III / Q000601:surgery; D008334:Mandible / Q000473:pathology / Q000601:surgery; D008963:Molar / Q000473:pathology; D009295:Nasal Bone / Q000473:pathology; D024343:Open Bite / Q000601:surgery*; D056948:Orthognathic Surgical Procedures / Q000379:methods*; D059229:Osteotomy, Sagittal Split Ramus / Q000379:methods; D057887:Overbite / Q000601:surgery; D012008:Recurrence; D012399:Rotation; D012658:Sella Turcica / Q000473:pathology; D016896:Treatment Outcome; D014716:Vertical Dimension; D055815:Young Adult