Purpose

Due to the inability to directly apply an intra-oral image with esthetic restoration to restore tooth shape in the computer-aided design system, this paper aims to propose a method that can use two-dimensional contours obtained from the image for the three-dimensional dental mesh model restoration.

Design/methodology/approach

First, intra-oral image and smiling image are taken from the patient, then teeth shapes of the images are designed based on esthetic restoration concepts and the pixel coordinates of the teeth’s contours are converted into the vertex coordinates in the three-dimensional space. Second, the dental mesh model is divided into three parts – active part, passive part and fixed part – based on the teeth’s contours of the mesh model. Third, the vertices from the teeth’s contours of the dental model are matched with ones from the intra-oral image and with the help of matching operation, the target coordinates of each vertex in the active part can be calculated. Finally, the Laplacian-based deformation algorithm and mesh smoothing algorithm are performed.

Findings

Benefitting from the proposed method, the dental mesh model with esthetic restoration can be quickly obtained based on the intra-oral image that is the result of doctor-patient communication. Experimental results show that the quality of restoration meets clinical needs, and the typical time cost of the method is approximately one second. So the method is both time-saving and user-friendly.

Originality/value

The method provides the possibility to design personalized dental esthetic restoration solutions rapidly.

中文翻译：

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一种基于牙齿特征轮廓的三维牙模型修复方法

目的

由于计算机辅助设计系统无法直接应用带有美学修复的口腔内图像来恢复牙齿形状，本文旨在提出一种方法，可以使用从图像中获得的二维轮廓进行三维牙网模型修复。

设计/方法/方法

首先获取患者的口腔内图像和微笑图像，然后基于美学修复概念设计图像的牙齿形状，并将牙齿轮廓的像素坐标转换为三维空间中的顶点坐标。其次，根据网格模型的牙齿轮廓，将牙网模型分为主动部分、被动部分和固定部分三部分。第三，将牙齿模型牙齿轮廓的顶点与口腔图像中的顶点进行匹配，通过匹配运算，计算出活动部位各顶点的目标坐标。最后，进行了基于拉普拉斯算子的变形算法和网格平滑算法。

发现

受益于所提出的方法，可以根据医患沟通的结果口腔内图像快速获得具有美学修复的牙齿网格模型。实验结果表明，修复质量满足临床需要，该方法的典型时间成本约为1秒。因此该方法既省时又方便用户。

原创性/价值

该方法提供了快速设计个性化牙齿美学修复解决方案的可能性。