Transition Curved Surface Generation Method And Its Application To Invisible Aligner Model

The transition curved surface generation is an extremely important part in the invisible aligner design, it is a very complex question that uses the regular shape, big entity volume base curved surface transition method to the irregular shape, small entity volume three-dimensional tooth model. Reusing three-dimensional model constructs the transition curved surface, not only satisfies the conventional request of the transition curved surface, but also requests to satisfy the invisible aligner the practical request. This article analyzes each kind of transition curved surface generation algorithm advantages and the invisible aligner generation method , choices PDE transition curved surface generation method, solves the transition curved surface generation question in the invisible aligner generation design.Firstly, researches transition curved surface generation method, including ball method, PDE method, energy method. According to development system characteristic, this article constructs the transition curved surface between the tooth with he PDE method.Secondly, analysis tradition invisible aligner generation method, proposes the new method of reusing the three-dimensional model to construct invisible invisible aligner, solves the invisible aligner practical question. Take the PDE method basic principle as the basis, according to invisible aligner design request, choices partial differential equation, curved surface type, boundary condition , establishes the mathematical model .Finally, in transition boundary determination, with a sort of vector approximation searching boundary point method of tissue segmentation is present by analyzing three dimensional segmentation, and single tooth is divided by citing solid incision method in RP technique, separates the boundary determination for the transition boundary. According to the boundary data characteristic which provides, express the boundary conditions by parameter with length average method, approximate sloves triangle surface piece apex extroversion vector with surface piece average extroversion vector.through analysis quite existing partial differential equation solution method, realizes the model solution with the finite element method, in solution process, carries on the iteration by relaxation factor.In the process of the realization of this system, with VC++6.0 and OpenGL for development tools, realizes the transition boundary determination,with MATLAB for development tools,produces the transition curved surface. Finally,the function, and the simulation results are presented. the shortcomings of the paper are analyzed, and some requests are put forward in the future.