title: Three-dimensional analysis of pharyngeal airway volume in adults with anterior position of the mandible.
abstract: BACKGROUND
  The purpose of this study was to examine whether the pharyngeal airway volume in adults with skeletal Class III malocclusion is greater than in subjects with Class I occlusion and whether the pharyngeal airway volume correlated with facial morphology.
  
  
  METHODS
  Cone-beam computed tomography scans were obtained from 60 subjects, who were assigned to 2 groups. The skeletal Class III malocclusion group consisted of 31 subjects (16 men, 15 women) who had planned on orthodontic treatment with orthognathic surgery. The Class I malocclusion group consisted of 29 subjects (14 men, 15 women). The pharyngeal airway volumes and areas were measured and compared with cephalometric variables.
  
  
  RESULTS
  The cross-sectional areas of the lower part of the pharyngeal airway and the volume of the upper part of the pharyngeal airway were greater in skeletal Class III malocclusion patients than in Class I malocclusion patients. The volume of the upper part of the pharyngeal airway showed negative correlations with ANB angle and the Wits appraisal, and positive correlations with SNB, APDI, pogonion to N-perp, gonial angle, and FMA.
  
  
  CONCLUSIONS
  The volume of the upper part of the pharyngeal space was greater in patients with skeletal Class III malocclusion, and the increased volume of the upper part of the pharyngeal airway showed significant correlations with measurements characterizing the anterior position of mandible.
authors.affiliation: Department of Orthodontics, Kangdong Sacred Heart Hospital, Hallym University Medical Center, Seoul, Korea.
authors.forename: Ji-Suk
authors.initials: JS
authors.lastname: Hong
authors.forename: Kyung-Min
authors.initials: KM
authors.lastname: Oh
authors.forename: Bo-Ram
authors.initials: BR
authors.lastname: Kim
authors.forename: Yoon-Ji
authors.initials: YJ
authors.lastname: Kim
authors.forename: Yang-Ho
authors.initials: YH
authors.lastname: Park
mesh_terms: D000293:Adolescent; D000328:Adult; D019412:Anatomy, Cross-Sectional; D002508:Cephalometry / Q000379:methods; D002680:Chin / Q000000981:diagnostic imaging; D054893:Cone-Beam Computed Tomography / Q000379:methods; D004825:Epiglottis / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008297:Male; D008311:Malocclusion, Angle Class I / Q000000981:diagnostic imaging; D008313:Malocclusion, Angle Class III / Q000000981:diagnostic imaging*; D008334:Mandible / Q000000981:diagnostic imaging*; D008437:Maxilla / Q000000981:diagnostic imaging; D009295:Nasal Bone / Q000000981:diagnostic imaging; D010160:Palate, Soft / Q000000981:diagnostic imaging; D010614:Pharynx / Q000000981:diagnostic imaging*; D012658:Sella Turcica / Q000000981:diagnostic imaging; D019291:Skull Base / Q000000981:diagnostic imaging; D014059:Tongue / Q000000981:diagnostic imaging; D055172:Vomer / Q000000981:diagnostic imaging; D055815:Young Adult; D015050:Zygoma / Q000000981:diagnostic imaging