Abstract: Three-dimensional (3D) scanning technology and 3D reconstruction based on CT images
are popular methods for tooth modeling recently. However, 3D scanning only can provides partial 3D
data of tooth crown, and the data of gingival root wrapped by the gum cannot be collected. Using CT
images for 3D reconstruction can get complete data model of tooth, but the process is time-consuming
and costly. In order to overcome the weakness of these methods above mentioned, a novel tooth
modeling method is proposed based on tooth crown and the features of tooth root. This method
establishes association rules for tooth crow and root based on the measured data of tooth, and 3D
model is constructed according to the Cardinal spline interpolation and Tangent weight - Laplacian
mesh editing. Compared the modeling results and original data, experimental results show that the
modeling method is efficient and feasible.

Key words: tooth root, tooth measurement, 3D modeling, spline curve