A method for automatic extraction of cervical margin line from mesh model of denture restoration preparation

Abstract

The invention discloses an automatic extracting method for a neck-edge line of a denture repair preparation mesh model. The method comprises the following steps: S1, determining an iteration starting point of the neck-edge line; S2, carrying out morphological processing on a characteristic region, so as to iteratively extract a characteristic line and build a characteristic point set; S3, iteratively extracting the neck-edge line on the basis of neighborhood traversal according to the iteration starting point of the neck-edge line and the characteristic point set. According to the method disclosed by the invention, the neck-edge line is extracted on the basis of the morphological processing and neighborhood traversal mode, the neck-edge line of denture repair preparation can be rapidly and accurately extracted, thus the calculated quantity is greatly reduced; the extraction accuracy is high; the demands on denture preparation are low, and therefore, the method can be widely applied to the field of extraction of the neck-edge line of the denture repair preparation.

Description

technical field [0001] The invention relates to the field of computer graphic construction of denture restoration, in particular to a method for automatically extracting the cervical margin line of a denture restoration preparation body mesh model. Background technique [0002] The extraction of the cervical margin is very important in denture restoration. At present, there are many studies on the extraction of the cervical margin at home and abroad, and there are various extraction methods. The semi-automatic extraction method has higher precision and lower requirements for denture restoration preparations, but requires the operator to judge the position of the cervical margin line with certain dental knowledge and select some points artificially. The requirements for personnel are high, and operator mistakes will bring unnecessary extraction errors to the extraction results, reduce the extraction accuracy, and require more manpower and material resources, resulting in high...

AI Technical Summary

Problems solved by technology

The semi-automatic extraction method has higher precision and lower requirements for denture restoration preparations, but requires the operator to judge the position of the cervical margin line with certain dental knowledge and select some points artificially. The requirements for personnel are high, and operator errors will bring unnecessary extraction errors to the extraction results, reduce the extraction accuracy, and require more manpower and material resources, resulting in higher extraction costs

More common is the adaptive extraction algorithm based on correlation coefficient and least squares fitting line, but this algorithm needs to manually select the starting point, and has high requirements for the preparation, and is easily affected by noise

In addition, there is also a fully automatic cervical line extraction algorithm based on principal component analysis. This algorithm also uses mathematical statistics to determine the direction of the cervical line. If the shape of the preparation is poor or there are many noises, the extraction will fail.

Generally speaking, most of the automatic neck edge extraction methods in the prior art are based on mathematical statistical methods, such as correlation coefficient, least squares fitting line and principal component analysis, etc., by approximately calculating the distribution direction of feature points to determine the neck line. The iterative direction of the margin line and the starting point of the cervical margin line extraction, these methods are computationally intensive, and the extraction direction of the cervical margin line is easily affected by noise, and the requirements for the preparation are also high

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