title: In vivo comparison of conventional and cone beam CT synthesized cephalograms.
abstract: OBJECTIVE
  To compare measurements from synthesized cone-beam computed tomography (CBCT) lateral cephalograms using orthogonal and perspective projections with those from conventional cephalometric radiographs.
  
  
  METHODS
  Thirty-one patients were imaged using CBCT and conventional cephalometry. CBCT volume data were imported in Dolphin 3D. Orthogonal and perspective lateral cephalometric radiographs were created from three-dimensional (3D) virtual models. Twelve linear and five angular measurements were made on synthesized and conventional cephalograms in a randomized fashion. Conventional image measurements were corrected for known magnification. Linear and angular measurements were compared between image modalities using repeated measures analysis of variance. Statistical significance was defined as an alpha level of .01.
  
  
  RESULTS
  With the exception of the Frankfort-mandibular plane angle (P < .0001), angular measurements were not statistically different for any modality (P > .01). Linear measurements, whether based on soft or hard tissue landmarks, were not statistically different (P > .01).
  
  
  CONCLUSIONS
  Measurements from in vivo CBCT synthesized cephalograms are similar to those based on conventional radiographic images. Thus, additional conventional imaging may generally be avoided when CBCT scans are acquired for orthodontic diagnosis.
authors.affiliation: Department of Oral and Maxillofacial Radiology, University of North Carolina, School of Dentistry Chapel Hill, NC 27599, USA.
authors.forename: Vandana
authors.initials: V
authors.lastname: Kumar
authors.forename: John
authors.initials: J
authors.lastname: Ludlow
authors.forename: Lucia Helena
authors.initials: LH
authors.lastname: Soares Cevidanes
authors.forename: André
authors.initials: A
authors.lastname: Mol
mesh_terms: D000328:Adult; D002508:Cephalometry / Q000379:methods*; D054893:Cone-Beam Computed Tomography / Q000379:methods*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods; D007180:Incisor / Q000473:pathology; D008297:Male; D008334:Mandible / Q000473:pathology; D008437:Maxilla / Q000473:pathology; D009295:Nasal Bone / Q000473:pathology; D011858:Radiographic Magnification; D012658:Sella Turcica / Q000473:pathology; D012984:Software; D014057:Tomography, X-Ray Computed / Q000379:methods*; D014584:User-Computer Interface; D014716:Vertical Dimension