Automatic filling algorithm of a tooth undercut mesh model on the basis of an included angle of normal vectors

Abstract

The invention discloses an automatic filling algorithm of a tooth undercut mesh model on the basis of an included angle of normal vectors. The automatic filling algorithm includes: inputting tooth models and virtual gingival boundary points, forming a tooth model pair by the tooth models of two adjacent teeth, identifying an undercut region for each tooth model pair, further identifying initial undercut region boundary points for each tooth model pair, preprocessing the initial undercut region boundary points to obtain final undercut region boundary point cloud, and finally reconstructing thefinal undercut region boundary point cloud of each tooth model pair into an undercut model. The undercut model is determined by means of an angle between a normal vector and a direction vector to realize automatic filling of undercuts, which brings convenience for later-period die molding and mechanical analysis. Moreover, the time is saved while human errors are greatly reduced to a certain extent.

Description

technical field [0001] The invention relates to a grid model construction method of a tooth grid model, in particular to an automatic filling algorithm of a tooth undercut grid model based on the angle between normal vectors. Background technique [0002] In recent years, digital oral technology has developed rapidly, and invisible orthodontics has gradually become popular. The work completed by the digital treatment assistance system is apart from establishing a tooth model to provide data support for the design of the treatment plan. Usually, in order to obtain a tooth model, it is first necessary to scan the plaster model optically to obtain the three-dimensional data of the jaw, then use digital set processing technology to segment the teeth, number the teeth to facilitate later operations, and then perform a series of operations on the digital model. [0003] Specifically, invisible aligners are a set of housings with teeth that allow the teeth to gradually reach the c...

AI Technical Summary

Problems solved by technology

They select a group of control points on two adjacent teeth in the undercut area, form a control surface through the control points, and then connect the edges of the two control surfaces to form an undercut mesh. Although this method is digitally formed However, the control points must be manually selected in the digital system. The selection rules of control points are complex, and each tooth has more than 8 control points. To complete a pair of aligners, many control points need to be selected. , which is very time-consuming

[0006] At present, there is a lack of an automatic filling method with less human intervention

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