A Deformation Method in a Wrapping Manner for Virtual Gingiva Based on Mass-Spring Model

In order to solve the problem that the boundary of gingiva is wrinkled after deformation in orthodontic simulation, we designed a simulation method in a wrapping manner for virtual gingiva based on the traditional Mass-spring model. Firstly, the transition boundary point between teeth and gums was selected as the active point in the deformation process, and the position of the active point was determined by wrapping it on the tooth surface after the correction operation. Then, in order to solve the problem of missing attachment point when the position of the active point is determined, we added a segment of tooth root based on the method of tooth contour curve fitting. Finally, we used the sum of surface curvature values to compare the experimental results. The experimental results show that the proposed method can effectively alleviate the problem of boundary wrinkles after gingival deformation in the case of large correction range, and improve the authenticity of the virtual orthodontic system.