Research On Technique For Oral Fixed Dentures Digital Design

With the improvement of people’s living standard, more and more peopleconcern oral health, the prevalence of oral disease reached97.6%, about50%ofdental caries need fixed partial denture to restore in China. The traditional methodof making dentures has a complex process and a long cycle, it can not guarantee theaccuracy, so computer-aided design and manufacturing technology begin topenetrate into the field of oral medicine. Dental restoration systems can be found inthe foreign markets, but its high price leads to increased costs of dental treatmentand limits the promotion and application in clinical. In contrast, there are nocommercial dental restoration systems in the domestic markets, so this paper studiesthe key issues about oral fixed denture of its digital design technologies anddevelops a denture design system with independent intellectual property rights.The topology reconstruction technology of triangular mesh model was studied.Compared and analyzed the existing methods, using a balanced binary tree auxiliarystructure to remove redundant secondary vertex, the model vertex and triangleinformation was extracted. The adjacency relationship between the vertices, edgesand triangles were obtained and the mesh topology diagram was established.Introduced curvature constraint in mesh optimization operator, the optimal meshtopology shape was reached and the dental3D model data structure was establishedbased on triangular mesh.The prepared teeth neck line extraction technique was studied. The paperproposed a neck line extraction method based on improved ant colony algorithm.Based on the standard ant colony algorithm, the paper regarded the averagecurvature as a measure of the feature points in cervical margin line, supplementeddistance function as a guide of the direction, and improved the standard ant colonyalgorithm heuristic function. For local optimization problem in the ant colonyalgorithm, the paper introduced dynamic random weights, and ultimately achievedadaptive interacted extraction of the neck line. The algorithm was verified theeffectiveness of the algorithm by examples.The triangular mesh isometric technique was studied. The paper proposed amethod based on discrete equidistant triangular mesh implicit surfaces. It took theneck line as the boundary line and used the seed triangle region growing method to the prepared tooth equidistant base face, established signed distance field withinbounding box, applied the improved MT algorithm to extract the isometric surfacefrom the signed distance field, realized the triangular surface offset and avoidedself-intersection problem of the existing method.Based on Qt4software development environment and the OpenGL graphicslibrary, the paper developed a fixed denture digital design system. The systemintegrated research theory of denture digital design technology in this article,established data storage structure of the system, designed the overall systemframework, and achieved inputs and outputs of three-dimensional teeth models, theinteractive storage of user information, freedom display of models, the fixeddenture design function.