title: Assessment of linear and angular measurements on three-dimensional cone-beam computed tomographic images.
abstract: OBJECTIVE
  The purpose of this research was to provide further evidence to demonstrate the precision and accuracy of maxillofacial linear and angular measurements obtained by cone-beam computed tomography (CBCT) images.
  
  
  METHODS
  The study population consisted of 15 dry human skulls that were submitted to CBCT, and 3-dimensional (3D) images were generated. Linear and angular measurements based on conventional craniometric anatomical landmarks, and were identified in 3D-CBCT images by 2 radiologists twice each independently. Subsequently, physical measurements were made by a third examiner using a digital caliper and a digital goniometer.
  
  
  RESULTS
  The results demonstrated no statistically significant difference between inter- and intra-examiner analysis. Regarding accuracy test, no statistically significant differences were found of the comparison between the physical and CBCT-based linear and angular measurements for both examiners (P = .968 and .915, P = .844 and .700, respectively).
  
  
  CONCLUSIONS
  3D-CBCT images can be used to obtain dimensionally accurate linear and angular measurements from bony maxillofacial structures and landmarks.
authors.affiliation: College of Dentistry, Department of Stomatology of University of São Paulo, Bauru, Brazil.
authors.forename: Carla R
authors.initials: CR
authors.lastname: Moreira
authors.forename: Marcelo A O
authors.initials: MA
authors.lastname: Sales
authors.forename: Patricia M L
authors.initials: PM
authors.lastname: Lopes
authors.forename: Marcelo G P
authors.initials: MG
authors.lastname: Cavalcanti
mesh_terms: D000328:Adult; D002508:Cephalometry / Q000379:methods* / Q000706:statistics & numerical data; D002680:Chin / Q000000981:diagnostic imaging; D054893:Cone-Beam Computed Tomography / Q000379:methods* / Q000706:statistics & numerical data; D004424:Ear Canal / Q000000981:diagnostic imaging; D005147:Facial Bones / Q000000981:diagnostic imaging*; D005260:Female; D005624:Frontal Bone / Q000000981:diagnostic imaging; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods* / Q000706:statistics & numerical data; D008297:Male; D008334:Mandible / Q000000981:diagnostic imaging; D008335:Mandibular Condyle / Q000000981:diagnostic imaging; D008437:Maxilla / Q000000981:diagnostic imaging; D008875:Middle Aged; D009295:Nasal Bone / Q000000981:diagnostic imaging; D015588:Observer Variation; D009915:Orbit / Q000000981:diagnostic imaging; D011856:Radiographic Image Enhancement / Q000379:methods; D019291:Skull Base / Q000000981:diagnostic imaging; D055815:Young Adult; D015050:Zygoma / Q000000981:diagnostic imaging