Tooth Completion and Reconstruction in Digital Orthodontics

In the field of digital orthodontics, dental models with complete roots are essential digital assets, particularly for visualization and treatment planning. However, intraoral scans typically capture only dental crowns, leaving roots missing. In this paper, we introduce a meticulously designed algorithmic pipeline to complete dental models while preserving crown geometry and mesh topology. Our pipeline begins with learning-based point cloud completion applied to existing dental crowns. We then reconstruct a complete tooth model, encompassing both the crown and root, to guide subsequent processing steps. Next, we restore the crown's original geometry and mesh topology using a strong Delaunay meshing structure; the correctness of this approach has been thoroughly established in existing literature. Finally, we optimize the transition region between crown and root using bi-harmonic smoothing. A key advantage of our approach is that the completed tooth model accurately maintains the geometry and mesh topology of the original crown, while also ensuring high-quality triangulation of dental roots.