Repeatability of three-dimensional measurements based on cone-beam CT images

Abstract

To investigate the repeatability of three-dimensional (3-D) cephalometric measurements for the clinical application of 3-D cephalometry. 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. 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. Most 3-D cephalometric measurements based on CBCT had high repeatability. However, some 3-D cephalometric measurements had limited repeatability.