Jawbone Segmentation with Trabecular Bone Preservation from Cone Beam CT Images

To segment jaw structures in both open and closed mouth states from cone beam CT images and to preserve the true structures of trabecular bones. Segmentation algorithms of the mandible and maxilla were designed based on their different structures. We detected edges in volume and segment edges of the mandible and maxilla whether the mouth of a patient was open or closed. The internal structures of the mandible and maxilla were preserved by a morphological method with different parameters, respectively. An axial plane corresponding to the bottom of the hard palate was identified so that the bone structures of the maxilla above this plane were removed. Finally, the mandibular surface was smoothed by a simple thresholding method, and the maxillary surface was optimized by a geodesic active contours method. The 3D jaw model was segmented automatically by our proposed procedure with high accuracy. The average dice coefficients of the mandible and maxilla were equal to 0.9709 and 0.9420, respectively. The proposed jaw segmentation algorithm is automatic and knowledge-driven. The segmented jaws truly demonstrate the cortical and trabecular bone structures. It may potentially assist doctors in diagnosis and surgical planning.