Abstract: Objective To compare cone-beam computed tomography (CBCT) and dental plaster model (DPM) in the measurement of the dental arches. Methods The dental arches of the 110 patients were scanned with the CBCT and their DPMs were also obtained. Two experienced examiners took eight arch measurements on the CBCT images and DPMs. And coupled arch measurements of these two clinical detection methods were compared separately by the Wilcoxon signed-rank test. Results No significant difference between DPM and CBCT were found in five arch measurements (P>0.01). Although there were statistical difference between DPM and CBCT in space analysis, total dental Bolton analysis and width between canine (P<0.01), the exactly mean differences of these three arch measurements were respectively less than 1 mm. Conclusion CBCT provided the same accuracy as DPM in the measurement of the dental arches.

Key words: Cone-beam computed tomography, dental plaster model, arch measurements