CBCT Image Segmentation and 3D technology

Summary

Cone-beam computed tomography (CBCT) is commonly used nowadays for orthodontic diagnosis, treatment planning, and outcome assessment because of its low dose of radiation. For the evaluation of orthodontic treatment, CBCT scans are acquired at different timepoints. These CBCT scans are subsequently segmented into different regions of interest, such as mandible, maxilla and teeth. 3-dimensional (3D) surface models of mandible, maxilla, and teeth at the different timepoints are then created and superimposed to visually and quantitively demonstrate the orthodontic changes. Moreover, these 3D surface models allow for finite element analysis to study the stress distribution in the mandible, maxilla and teeth. However, it is also due to CBCT’s low radiation that the scans have noise and low contrast in visual impression. Currently, the most difficult step in the orthodontic evaluation is the image segmentation. There is no clear edge between teeth root and alveolar bone and their gray values are in the similar level. Therefore, it is not easy to segment teeth and alveolar bone. In CBCT scans, the adjacent teeth are mostly connective to each other which makes segmentation of individual tooth more difficult. To date no fully-automated algorithm has been developed that can reliably segment the different bony structures in CBCT scans. Therefore, a large amount of manual work is required to reconstruct 3D surface models of mandible, maxilla, and teeth. Consequently, the patient-specific orthodontic treatment is hampered by this time-consuming task. In order to reduce the work of image segmentation, we aim to build the triangle mesh model to distinguish the morphology of teeth, develop a 3D point cloud registration method to recognize mandible and maxilla, and train a convolutional neural network (CNN) to segment mandible, maxilla, and teeth in CBCT scans.

The first seminar has already been planned and will take place in Shuren University in October, 2019. Based on the discussion in the first seminar and the progress of the ongoing research project, we plan to start the second seminar which will be held in VUmc, The Netherlands. In this seminar, the new results of the research project will be presented and the plan of the software package development will be made. Surgeons and dentists will be invited to present the challenging clinical issues which are related to the reconstruction of oral and maxillofacial region. 3D technology in the medical field will also be presented in this seminar. After this seminar, we plan to send researchers to the Software Development Center in Shuren University for three months to work together with Chinese researchers on the software development. We expect to get PhD projects from Institute of Information Technology and have further collaboration with Shulan International Medical Center.

Details

Project number

040.20.010

Main applicant

T. Forouzanfar

Affiliated with

Amsterdam UMC - Locatie VUmc, Oral Diseases and dental surgery

Duration

18/11/2019 to 21/11/2019