title: Evaluation of mandibular volume classified by vertical skeletal dimensions with cone-beam computed tomography.
abstract: OBJECTIVE
  To investigate the relationship between anteroposterior and vertical differences in maxillofacial morphology and mandibular volume.
  
  
  METHODS
  Subjects comprised 213 Japanese adults (84 males and 129 females) who were divided into three groups based on mandibular basal arch (ANB) and Wits, measured in a cephalometric analysis: Class I (-1° ≤ ANB < 4°,-1 mm ≤ Wits < 0 mm), Class II (ANB ≥ 4°, Wits ≥ 0), and Class III (ANB <-1°, Wits <-1 mm). Subjects were also divided into three groups based on the mandibular plane angle (Mp), as follows: hypodivergent (Mp < 23°), normodivergent (Mp  =  23-30°), and hyperdivergent (Mp > 30°) groups. Mandibular volume was measured from cone-beam computed tomographic images that were analyzed using Analyze™ image processing software and compared among the three groups in each classification.
  
  
  RESULTS
  No significant differences were noted in mandibular volume among Classes I, II, and III. An inverse relationship was found between mandibular volume and Mp, and a significant difference was noted in mandibular volume between the hypodivergent and hyperdivergent groups.
  
  
  CONCLUSIONS
  In addition to two-dimensional analysis, such as lateral cephalometry, three-dimensional information such as volume, provided by cone-beam computed tomography, contributes to a more detailed assessment of maxillofacial morphology.
authors.affiliation: a  Student, Department of Orthodontics, School of Dentistry, Showa University, Tokyo, Japan.
authors.forename: Takatoshi
authors.initials: T
authors.lastname: Nakawaki
authors.affiliation: b  Associate Professor, Department of Orthodontics, School of Dentistry, Showa University, Tokyo, Japan.
authors.forename: Tetsutaro
authors.initials: T
authors.lastname: Yamaguchi
authors.affiliation: a  Student, Department of Orthodontics, School of Dentistry, Showa University, Tokyo, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Tomita
authors.affiliation: a  Student, Department of Orthodontics, School of Dentistry, Showa University, Tokyo, Japan.
authors.forename: Yu
authors.initials: Y
authors.lastname: Hikita
authors.affiliation: c  Research Assistant, Department of Orthodontics, School of Dentistry, Showa University, Tokyo, Japan.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Adel
authors.affiliation: c  Research Assistant, Department of Orthodontics, School of Dentistry, Showa University, Tokyo, Japan.
authors.forename: Koshu
authors.initials: K
authors.lastname: Katayama
authors.affiliation: d  Professor, Department of Orthodontics, School of Dentistry, Showa University, Tokyo, Japan.
authors.forename: Koutaro
authors.initials: K
authors.lastname: Maki
mesh_terms: D000328:Adult; D002508:Cephalometry; D054893:Cone-Beam Computed Tomography; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008334:Mandible / Q000033:anatomy & histology*; D014716:Vertical Dimension; D055815:Young Adult
keywords: Cone-beam computed tomography; Mandibular volume; Maxillofacial morphology; Skeletal pattern