title: [Repeatability of three-dimensional measurements based on cone-beam CT images].
abstract: OBJECTIVE
  To investigate the repeatability of three-dimensional (3-D) cephalometric measurements for the clinical application of 3-D cephalometry.
  
  
  METHODS
  Forty-nine measurements that widely used in traditional cephalometric analyses were defined in 3-D cone-beam CT (CBCT) images. Three examiners identified landmarks on CBCT images of 17 subjects with normal occlusion, respectively, and 3-D measurements were exported automatically by software SimPlant. Inter-examiner reliability correlation coefficients (ICC) were obtained for all measurements.
  
  
  RESULTS
  Repeatability of 36 measurements was high (ICC value greater than 0.9), including SNA, SNB. Repeatability of 11 measurements was moderate (ICC value between 0.8 and 0.9), including CoL-GoL, CoL-MSP. Repeatability of 2 measurements was low (ICC value lower than 0.8), including Gn-MSP and MPR-MSP.
  
  
  CONCLUSIONS
  Most 3-D cephalometric measurements based on CBCT had high repeatability. However, some 3-D cephalometric measurements had limited repeatability.
authors.affiliation: Department of Orthodontics, Capital Medical University School of Stomatology, Beijing 100050, China.
authors.forename: Shu-Ran
authors.initials: SR
authors.lastname: Liang
authors.forename: Wei-Min
authors.initials: WM
authors.lastname: Gao
authors.forename: Yu-Xing
authors.initials: YX
authors.lastname: Bai
authors.forename: Wei-Jiao
authors.initials: WJ
authors.lastname: Yin
authors.forename: Nan
authors.initials: N
authors.lastname: Zhang
mesh_terms: D002508:Cephalometry; D054893:Cone-Beam Computed Tomography; D006801:Humans; D021621:Imaging, Three-Dimensional; D015588:Observer Variation; D015203:Reproducibility of Results