Quantitative evaluation of the accuracy of micro-computed tomography in tooth measurement.

Micro-computed tomography (MCT) is a noninvasive technique for visualizing morphological characteristics of teeth in a detailed and accurate manner, without causing any tooth destruction. A large amount of information can be obtained from such scans. The slices can be recreated in any plane, and the data can be represented as either two-dimensional (2D) or three-dimensional (3D) images. In addition, the internal and external anatomy can be demonstrated simultaneously or separately, and the images can be assessed qualitatively and quantitatively. However, only the qualitative accuracy of MCT had been evaluated previously. The aim of the present study was to evaluate the accuracy of MCT quantitatively by comparing the values obtained by MCT with those of other imaging methods. Twelve teeth were scanned using a desktop X-ray micro-CT scanner, and the images were reconstructed and measured. Values obtained by direct measurement served as the primary reference for linear measurements. Measurements made by a 3D scanner and by photography were additional references. MCT was found to be a reliable method of making linear measurements and may be a useful device for measuring distance and for observing both internal and external tooth structure using the reconstructed 3D form.