A cone-beam CT-based technique to augment the 3D virtual skull model

Abstract

Objective: The purpose of this study was to evaluate the use of a double CBCT scan procedure with a modified wax bite wafer in order to augment the 3D virtual skull model with a detailed dental surface. Methods: Ten patients were scanned following a standardized CBCT scanning protocol with their wax bite wafer in place. The impressions of the dental arches and the wax bite wafer were scanned for each patient separately using a high resolution standardized CBCT scanning protocol. Surface-based rigid registration using iterative closest points (ICP) was used to fit the virtual models on the wax bite wafer. Automatic rigid point-based registration of the wax bite wafer on the patient scan was performed to implement the digital virtual dental arches into the patients’ skull model. Results: Probability error histograms showed errors of ±0.22 mm (25% percentile), ±0.44 mm (50% percentile) and ±1.09 mm (90% percentile) for ICP surface matching. The mean registration error for automatic point-based rigid registration was 0.18 ± 0.10 mm (range: 0.13–0.26 mm). Conclusion: The results of this study show the potential of a double CBCT scan procedure with a modified wax bite wafer to set-up a 3D virtual augmented model of the skull.