基于生长原理的磨牙修复体面特征区域识别方法

GROWTH PRINCIPLE BASED RECOGNITION METHOD FOR OCCLUSAL SURFACE FEATURE REGIONS OF MOLAR RESTORATION

为精确加工出牙齿修复体的面,以保证其咬合功能,可将修复体的面划分为一系列"沟、窝、嵴、包"型的特征区域分别进行加工。基于生长原理,提出一种在磨牙修复体的STL模型上进行面特征区域识别的方法。对于STL模型上的某一局部面域,首先根据法矢的分布情况,进行沟(嵴)与窝(包)的判别。对于沟(嵴)区域,先沿法矢变化最小的方向生长出沟底线(嵴顶线),再利用"等夹角环"逐层向外生长形成边界。对于窝(包)区域,直接利用"等夹角环"逐层向外生长确定其边界。在标准磨牙STL模型中进行了特征区域的识别。实例证明,所提出的基于生长原理的识别方法是一种可行的方法。

In order to make up the occlusal surface of a molar restoration accurately so that it can occlude well,the occlusal surface of restoration may probably be partitioned into some feature regions such as gouge, socket, ridge and bulge and then to make each one respectively. Based on the principle of natural growth, in this paper we present an approach of feature regions recognition in the STL model of a molar restoration. As to a local region in the STL model, it is distinguished whether it＇s a gouge（ or ridge） or a socket（ or bugle） according to distribution of normal vectors. As to a gouge（ or ridge）, the bottom （or top） line is established along the direction on which normal vectors vary minimally, and its edge can be obtained by extending outward ring-by-ring using ＂equal angle ring＂. As to a socket（ or bulge） ,its edge can be obtained by directly extending outward ring-by ring using ＂equal angle ring＂. Feature regions recognition was done in standard molar restoration STL model. The instance shows that this growth principle based recognition method is a feasible one.