Comparison of the accuracy of different cone beam computed tomography systems in measuring the volume of external root resorption.

Abstract

Purpose: The aim of this study is to compare the accuracy of root resorption volume measurements among three cone-beam computed tomography (CBCT) devices using various imaging parameters.

Materials and methods: A total of 42 external root resorption (ERR) defects were mechanically created on the buccal and palatinal surfaces of the roots of seven extracted human teeth. Volume measurements of the defects were performed using three CBCT devices and six different imaging protocols. CBCT measurements were then compared with those calculated from micro-computed tomography (micro-CT) images.

Results: The mean absolute error values indicated that the rate of measurement accuracies from best to worst was obtained with KaVo 3D eXam (0.125 mm voxel, 0.2 mm voxel, respectively), Orthophos XG 3D (0.1 mm voxel, 0.16 mm voxel, respectively), and Rainbow CT (0.2 mm voxel, 0.3 mm voxel, respectively). No statistically significant difference was found between any of the CBCT measurements in comparison to the micro-CT evaluations.

Conclusion: Although external root resorption is a small object to evaluate using CBCT, larger voxel sizes (e.g., 0.3 mm) of CBCT systems can be employed during scanning without compromising image quality.