Comparative study of reproducibility and accuracy in measuring mesiodistal tooth sizes using three different methods: 2D digital, 3D CBCT, and 3D CBCT segmented

To develop a 3D cone-beam computed tomography (CBCT) method (CBCT method) for determining tooth sizes and arch dimensions and to compare the accuracy and reproducibility of that method with those of a previously described 3D segmented CBCT method (CBCT seg. method) and a 2D digital method. Plaster study models and CBCT images were available for 34 patients. For the first method, the plaster study casts were digitalized and measured using the 2D digital method. For the second method, CBCT seg. method, the CBCT images were sent in DICOM format to InVivoDental(A (R)) Company for segmentation and conversion into three-dimensional images of the models. For the third method, CBCT method, axial cuts were performed on the CBCT images, and tooth sizes and arch dimensions were measured using Anatomage(A (R)) software. Significant differences were found between the tooth size measurements obtained with the 3D CBCT method and the 2D digital method, but not for the intercanine width, intermolar width, and arch length. There were no significant differences between the measurements obtained with the CBCT seg. method and the 2D digital method. A 3D CBCT method has been developed. It presented good accuracy for the intercanine width, intermolar width, and arch length, but not for the mesiodistal tooth sizes. Model segmentation will be necessary for measurements of tooth size.