Method for fast and accurately detecting dental arch line on three-dimension grid dental cast

Abstract

Disclosed is a quick and accurate detecting dental arch on a three-dimensional mesh dental model, belonging to the field of computer aided f. The method includes five steps, simple human-computer interactive confirmation of an occlusal plane, sifting initial reference point, fitting an initial dental arch, extracting the final reference point and fitting the final dental arch. The method of the invention only needs simple human-computer interactive operation which helps achieve high degree of automation and avoid the general complex computation; linear computation which is mainly used in the invention can detect dental arch on the three-dimensional dental model quickly, steadily and precisely, valued in application in the field of computer aided orthodontic aesthetics.

Description

Technical field [0001] The invention relates to the field of computer-aided design, in particular to a method for detecting dental arch lines on a three-dimensional dental model in computer-aided orthodontic treatment. Background technique [0002] The shape of the dental arch is of great significance in the diagnosis and treatment of orthodontics. The orthodontist needs to draw the dental arch line of the upper and lower jaw to judge the degree of malocclusion. Measuring the arch of the dental arch for crowding analysis is an important quantitative evaluation for orthodontic diagnosis. in accordance with. Correcting the abnormal dental arch shape and establishing a personalized dental arch shape that matches the individual patient is an important goal of orthodontics. Orthodontic doctors first used the Bonwill-Hawley principle to draw individual arch diagrams, but the drawing process is extremely complicated and cumbersome. Later, various mathematical models were used to simulat...

AI Technical Summary

Problems solved by technology

After the three-dimensional measurement technology is applied to orthodontic treatment, the digital three-dimensional dental model can be easily obtained, so a method of drawing the dental arch line on the three-dimensional digital model appears, and Joon Huang et al. manually select the three-dimensional digital dental model. Refer to points to fit the arch line. Schicho et al. define the arch line on the 3D digital model through human-computer interaction. These manual or interactive algorithms require frequent operations by orthodontists and are time-consuming and laborious.

Kondo introduced an automatic dental arch detection in the paper Robust archdetection and tooth segmentation in 3D images of dental plaster models (In: Proceedings International Workshop on Medical Imaging and AugmentedReality [C], Hong Kong, China, 2001: 241-246) Line method, first determine the occlusal plane, adjust the coordinates of the dental model according to the occlusal plane, and then convert the three-dimensional model into a two-dimensional grayscale image. The brightness value of the grayscale image represents the coordinate z value (ie, the height value). Use the gradient orientation analysis method to find the discontinuous points in the gradient direction on the high-degree image as the initial reference point, use the initial reference point to fit an initial dental arch line, and extract the final feature points on the grayscale image based on the initial dental arch line , fitting the extracted final feature points to obtain the final arch line. This method of automatic detection of dental arch line has good adaptability, but since the 3D model needs to be converted into a 2D grayscale image, in the conversion process Part of the grid vertex information will be lost. If the grid vertex information is not lost, a large amount of redundant data will be introduced. The gradient direction analysis method used when detecting the initial feature points involves complex calculations, and the calculation data volume is large. Models can take a lot of time

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