3D reconstruction of lower anterior teeth from CBCT images: automatic segmentation with manual refinements

OBJECTIVE: To develop a well-detailed and reproducible tooth segmentation method, when quantifying tooth volumetric measurements is needed. MATERIAL AND METHODS: This was an in vitro study in which lower incisors and canines of five patients were 3D reconstructed by means of an automatic segmentation with manual refinements process. All the images were obtained using a 0.3-mm voxel size CBCT imaging. The software utilized was the ITK-SNAP®. The primary outcomes were the intra-rater and inter-rater reliabilities and the respective measurement errors. RESULTS: The intra-rater reliability was excellent, with a mean measurement error of 4.16%. The inter-rater reliability was good, with a mean measurement error of 7.11%. Accuracy assessment was not possible, as the assessed teeth were not extracted. CONCLUSIONS: Although the described method is reliable, tooth volumetric error measurements may become significant, depending on the assessed situation.