Accuracy of volumetric measurement of teeth in vivo based on cone beam computer tomography.
OBJECTIVE
to evaluate the accuracy of cone beam computed tomography (CBCT) for volumetric measurement of teeth, using micro-computed tomography (Micro-CT) as the reference standard.


METHODS
The Department of Orthodontics at Sichuan University. The sample consisted of 27 maxillary and mandibular premolars of 15 patients, planned to be extracted for orthodontic treatment.


METHODS
The 27 teeth were subjected to standardized CBCT scanning before extraction and Micro-CT scanning after extraction. From CBCT data, teeth were tissue segmented and then three-dimensionally (3D) reconstructed, while from Micro-CT data, teeth were 3D reconstructed directly. Tooth volumes were then calculated. The intra-observer repeatability and reproducibility of two observers and the overall between-instrument agreement of the measurements were evaluated using intra-class correlation coefficients (ICCs) and concordance correlation coefficient (CCC), respectively.


RESULTS
The intra-observer repeatability was high for both observers. ICCs were 0.999 and 0.998, respectively. The reproducibility of the two observers was also high (ICC, 0.740). The overall between-instrument agreement of the measurements was good, and CCC was 0.993 and its lower 95% confidence interval was 0.989.


CONCLUSIONS
The accuracy of the CBCT method for volumetric measurement of teeth in vivo is comparable to the Micro-CT method in vitro. The CBCT method has the potential possibility to be applied in studies on root resorption associated with orthodontic force. Further study is needed to prove the sensitivity of the method.
Department of Orthodontics, West China College of Stomatology, Sichuan University, Chengdu, China.
Y
Y
Wang
S
S
He
L
L
Yu
J
J
Li
S
S
Chen
D000293:Adolescent; D001641:Bicuspid / Q000000981:diagnostic imaging*; D002648:Child; D054893:Cone-Beam Computed Tomography / Q000379:methods / Q000592:standards*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods; D008297:Male; D015588:Observer Variation; D009811:Odontometry / Q000379:methods / Q000592:standards; D009929:Organ Size; D015203:Reproducibility of Results; D019227:Tooth Apex / Q000000981:diagnostic imaging; D014092:Tooth Root / Q000000981:diagnostic imaging; D055114:X-Ray Microtomography / Q000379:methods / Q000592:standards; D055815:Young Adult