title: Three-dimensional changes in pharyngeal airway in skeletal class III patients undergoing orthognathic surgery.
abstract: OBJECTIVE
  It has often been hypothesized that mandibular setback surgery causes narrowing of the pharyngeal airway. We examined whether the pharyngeal airway narrowed after orthognathic surgery in patients undergoing either mandibular setback surgery or bimaxillary surgery and whether the amount of narrowing of the pharyngeal airway was any different after mandibular setback surgery or bimaxillary surgery.
  
  
  METHODS
  Cone-beam computed tomography scans were obtained for 21 patients who were assigned to either mandibular setback surgery or bimaxillary surgery. The anteroposterior dimension, lateral width, cross-sectional area, and volume of each subject's pharyngeal airway were measured before and after surgery.
  
  
  RESULTS
  The pharyngeal airway showed significant narrowing after both mandibular setback surgery and bimaxillary surgery. The amount of change in the anteroposterior dimension and cross-sectional area on the posterior nasal spine plane and the length of the pharyngeal airway showed significant differences between the 2 groups.
  
  
  CONCLUSIONS
  The amount of narrowing of the pharyngeal airway was smaller in patients undergoing bimaxillary surgery than in the patients undergoing mandibular setback surgery.
authors.affiliation: Department of Orthodontics, Kangdong Sacred Heart Hospital, Hallym University Medical Center, GangDong-Gu, Seoul, Korea.
authors.forename: Ji-Suk
authors.initials: JS
authors.lastname: Hong
authors.forename: Yang-Ho
authors.initials: YH
authors.lastname: Park
authors.forename: Yoon-Ji
authors.initials: YJ
authors.lastname: Kim
authors.forename: Soon-Min
authors.initials: SM
authors.lastname: Hong
authors.forename: Kyung-Min
authors.initials: KM
authors.lastname: Oh
mesh_terms: D000293:Adolescent; D000328:Adult; D019412:Anatomy, Cross-Sectional; D002508:Cephalometry / Q000379:methods; D054893:Cone-Beam Computed Tomography / Q000379:methods; D004825:Epiglottis / Q000000981:diagnostic imaging; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods*; D019248:Jaw Fixation Techniques / Q000295:instrumentation; D008297:Male; D008313:Malocclusion, Angle Class III / Q000601:surgery*; D008334:Mandible / Q000601:surgery; D008437:Maxilla / Q000601:surgery; D009295:Nasal Bone / Q000000981:diagnostic imaging; D056948:Orthognathic Surgical Procedures / Q000379:methods*; D019340:Osteotomy, Le Fort / Q000379:methods; D059229:Osteotomy, Sagittal Split Ramus / Q000379:methods; D010160:Palate, Soft / Q000000981:diagnostic imaging; D010614:Pharynx / Q000000981:diagnostic imaging*; D011378:Prognathism / Q000601:surgery; D055815:Young Adult