CT Dental Impression Surface Extraction Without Mesh Distortion

The patent changes the fundamental parameter of how the digital surface mesh is generated by using a point-based approach instead of traditional triangle mesh generation. This involves representing the surface as a collection of points with associated normals and curvatures, which can be processed much faster than generating and then simplifying large triangle meshes. The point-based representation eliminates the need for post-processing simplification while maintaining accuracy.

The patent extracts only the essential geometric information needed for accurate surface representation - specifically points, normals, and curvatures - without generating the full triangle mesh structure. By taking out only the critical elements (points with their geometric properties) and eliminating the complex triangle connectivity, the method achieves high accuracy without the distortions and complexities of conventional mesh generation.

The patent implements feedback by using the computed geometric properties (normals and curvatures) of the points to guide the surface selection process. Instead of relying on arbitrary iso-values, the method uses feedback from the actual geometric characteristics of the volumetric data to automatically determine the correct surface position and shape, ensuring topological accuracy without requiring manual iso-value adjustment.

The patent inverts the conventional approach by not starting with a triangle mesh that needs simplification. Instead, it directly generates a point-based representation that inherently avoids the degenerate triangle problem. By working backwards from the final desired outcome (an accurate, simplified surface representation) and using points rather than triangles as the fundamental element, the method eliminates the need for simplification operations that create degenerate triangles.