A method and system for filling cavities on the proximal surface of tooth crowns based on CBCT data

Abstract

This invention relates to a method for filling cavities on the proximal surfaces of tooth crowns based on CBCT data. By utilizing the proximal information from real CT data, cavities on the proximal surfaces of tooth crowns are filled, making the filled surface closer to the actual shape of the tooth crown. This method for filling cavities on the proximal surfaces of tooth crowns based on CBCT data can more realistically construct a proximal mesh using CBCT data, generating a reasonable and practical proximal mesh.

Description

Technical Field

[0001] This invention relates to the field of orthodontic technology, and in particular to a method and system for filling cavities on the proximal surfaces of tooth crowns based on CBCT data. Background Technology

[0002] Currently, in invisible orthodontic treatment, some crown data obtained from intraoral scans may show overlap, resulting in a lack of interproximal mesh information in the scanned crown mesh. It is difficult to construct accurate interproximal meshes using geometric methods or simple direct filling, posing challenges for both aligner production and patient fit. Summary of the Invention

[0003] The technical problem to be solved by this invention is to design a method and system for filling cavities on the proximal surfaces of tooth crowns based on CBCT data, which can generate reasonable and realistic proximal meshes of teeth, thus solving the existing technical problems.

[0004] To solve the above-mentioned technical problems, the method for filling cavities on the proximal surface of tooth crowns based on CBCT data of the present invention includes the following steps:

[0005] Step S1: Obtain the data of unfilled crowns on the adjacent surfaces from the tooth segmentation software, and determine the areas that need to be filled based on the common tangent line of adjacent teeth;

[0006] Step S2: Perform cavity filling on the mesial and distal surfaces of the tooth to be filled. Determine if the adjacent mesial and distal teeth have a common tangent line, denoted as the mesial tangent line and distal tangent line. If there is no common tangent line, do not perform the cavity filling. If there is a common tangent line, proceed to the following steps:

[0007] Step S21: Sort the boundary edge data with these points according to the near-middle and far-middle adjacent cutting line data, so that the cutting line points of the two faces have the same direction;

[0008] Step S22: Calculate the average length of the boundary edge based on the sorted boundary edges in step S21, denoted as aveBorderEL, and perform triangular meshing on the hole, denoting the initially constructed triangular mesh as HolePatch.

[0009] Step S3: Combine and merge the mesh used for filling the cavity with the original crown mesh from Step S2;

[0010] Step S4: Obtain the CBCT root bone data that has been registered with the crown, and deform the CBCT corresponding to each tooth position;

[0011] Step S5: Perform intersection detection between the HolePatch mesh from step S2 and the deformed CBCT. Use the vertices of the HolePatch mesh as control points and the points that intersect with the CBCT as target points. Perform thin-plate spline deformation on the HolePatch mesh area to make the cavity filling mesh closer to the real tooth crown proximal surface.

[0012] Step S6: Perform Laplacian smoothing on the mesh near the proximal surface of the crown in step S5 to prevent the mesh from warping at the connection points between the proximal surface mesh and the crown mesh.

[0013] Furthermore, the hole-filling operation in step S2 also includes step S23: refining the triangular mesh constructed in step S22 to make the hole-filling mesh better.

[0014] Furthermore, step S3 also includes smoothing the edge mesh of the merged crown mesh.

[0015] Furthermore, in step S4, since the root data of CBCT is generally smaller than the crown data, CBCT is expanded based on the boundary point data of the adjacent surfaces of the crown to make CBCT fit the crown.

[0016] This invention also provides a system for filling cavities on the proximal surfaces of tooth crowns based on CBCT data, comprising:

[0017] At least one processor; and

[0018] At least one memory communicatively connected to the processor;

[0019] The memory stores instructions that can be executed by a processor, which, when executed by the processor, causes the electronic device to perform the aforementioned method for filling cavities on the proximal surfaces of tooth crowns based on CBCT data.

[0020] The beneficial effects of this invention are as follows: The method for filling cavities on the proximal surfaces of tooth crowns based on CBCT data utilizes the proximal information from real CT data to fill cavities on the proximal surfaces of tooth crowns, making the filled surface closer to the actual shape of the tooth crown. This method can more realistically construct proximal meshes using CBCT data, generating reasonable and practical proximal tooth meshes. Attached Figure Description

[0021] The specific embodiments of the present invention will be further explained below with reference to the accompanying drawings.

[0022] Figure 1 This is a flowchart of the method for filling cavities on the proximal surface of a tooth crown based on CBCT data according to the present invention;

[0023] Figure 2A schematic diagram of the tangent lines on the adjacent surfaces of a tooth to be filled;

[0024] Figure 3 A schematic diagram of the CBCT mesh without deformation;

[0025] Figure 4 A schematic diagram of a CBCT mesh deformed according to the crown cleavage line;

[0026] Figure 5 This is a schematic diagram of a dental crown mesh used for filling cavities.

[0027] Figure 6 This is a schematic diagram of a crown mesh deformed according to a CBCT mesh.

[0028] Figure 7 This is a schematic diagram of the crown mesh after Laplace smoothing. Detailed Implementation

[0029] Example 1

[0030] Combination Figure 1 The method for filling cavities on the proximal surface of tooth crowns based on CBCT data in this embodiment includes the following steps:

[0031] Step S1: Obtain the data of unfilled crowns on adjacent surfaces from the tooth segmentation software, such as... Figure 2 As shown, the area requiring filling is determined based on the common tangent line of adjacent teeth;

[0032] Step S2: Perform cavity filling on the mesial and distal surfaces of the tooth to be filled. Determine if the adjacent mesial and distal teeth have a common tangent line, denoted as the mesial tangent line and distal tangent line. If there is no common tangent line, do not perform the cavity filling. If there is a common tangent line, proceed to the following steps:

[0033] Step S21: Sort the boundary edge data with these points according to the near-middle and far-middle adjacent cutting line data, so that the cutting line points of the two faces have the same direction;

[0034] Step S22: Calculate the average length of the boundary edge based on the sorted boundary edges in step S21, denoted as aveBorderEL, and perform triangular meshing on the hole, denoting the initially constructed triangular mesh as HolePatch.

[0035] Step S23: Refine the triangular mesh constructed in step S22 to make the hole-filling mesh better;

[0036] Step S3: Combine the mesh for filling the cavity from step S2 with the original crown mesh, and smooth the edge mesh of the combined crown mesh.

[0037] Step S4: Obtain the CBCT root bone data after registration with the crown, and perform deformation analysis on the CBCT corresponding to each tooth position; since the CBCT root data is generally smaller than the crown data, such as... Figure 4 As shown, CBCT expansion is performed based on the boundary point data of the adjacent surfaces of the crown to ensure that the CBCT fits the crown perfectly; the undeformed CBCT mesh is shown below. Figure 3 As shown;

[0038] Step S5: Perform intersection detection between the HolePatch mesh from Step S2 and the deformed CBCT. Use the vertices of the HolePatch mesh as control points and the points intersecting with the CBCT as target points. Perform thin-plate spline deformation on the HolePatch mesh area to make the cavity-filling mesh closer to the actual proximal surface of the crown; only the crown mesh for cavity filling is as follows... Figure 5 As shown, the crown mesh deformed according to the CBCT mesh is as follows: Figure 6 As shown;

[0039] Step S6: Perform Laplacian smoothing on the mesh near the proximal surface of the crown from step S5 to prevent warping at the junction of the proximal surface mesh and the crown mesh. Figure 7 As shown.

[0040] The tooth crown proximal cavity filling method based on CBCT data in this embodiment utilizes the proximal information of real CT data to fill the proximal cavity of the tooth crown, making the filled surface of the tooth crown closer to the real tooth crown shape. By using CBCT data, a more realistic proximal mesh can be constructed, and a reasonable and realistic tooth proximal mesh can be generated.

[0041] Example 2

[0042] This embodiment of the tooth crown interproximal cavity filling system based on CBCT data includes:

[0043] At least one processor; and

[0044] At least one memory communicatively connected to the processor;

[0045] The memory stores instructions that can be executed by a processor, which are then executed by the processor to enable the electronic device to perform the tooth crown proximal cavity filling method based on CBCT data in Embodiment 1.

[0046] Many specific details have been set forth in the foregoing description to provide a thorough understanding of the present invention. However, the above description is merely a preferred embodiment of the present invention, and the present invention can be implemented in many other ways different from those described herein. Therefore, the present invention is not limited to the specific embodiments disclosed above. Furthermore, any person skilled in the art can make many possible variations and modifications to the technical solutions of the present invention, or modify them into equivalent embodiments, using the methods and techniques disclosed above, without departing from the scope of the present invention. Any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention, without departing from the content of the present invention, shall still fall within the protection scope of the present invention.

Claims

1. A method for tooth crown proximal cavity filling based on CBCT data, characterized in that: Includes the following steps: Step S1: Obtain the data of unfilled crowns on the adjacent surfaces from the tooth segmentation software, and determine the areas that need to be filled based on the common tangent line of adjacent teeth; Step S2: Perform cavity filling operation on the mesial and distal proximal surfaces of the tooth to be filled. Determine whether the adjacent mesial and distal teeth of the tooth to be filled have a common tangent line, and record it as the mesial proximal tangent line and the distal proximal tangent line. If there is no common tangent line, no hole-filling operation will be performed; if there is a common tangent line, proceed with the following steps: Step S21: Sort the boundary edge data with these points according to the near-middle and far-middle adjacent cutting line data, so that the cutting line points of the two faces have the same direction; Step S22: Calculate the average length of the boundary edge based on the sorted boundary edges in step S21, denoted as aveBorderEL, and perform triangular meshing on the hole, denoting the initially constructed triangular mesh as HolePatch. Step S3: Combine and merge the mesh used for filling the cavity with the original crown mesh from Step S2; Step S4: Obtain the CBCT root bone data that has been registered with the crown, and deform the CBCT corresponding to each tooth position; Step S5: Perform intersection detection between the HolePatch mesh from step S2 and the deformed CBCT. Use the vertices of the HolePatch mesh as control points and the points that intersect with the CBCT as target points. Perform thin-plate spline deformation on the HolePatch mesh area to make the cavity filling mesh closer to the real tooth crown proximal surface. Step S6: Perform Laplacian smoothing on the mesh near the proximal surface of the crown in step S5 to prevent the mesh from warping at the connection points between the proximal surface mesh and the crown mesh.

2. The method of claim 1, wherein: The hole-filling operation in step S2 also includes step S23: refining the triangular mesh constructed in step S22.

3. The method of claim 1, wherein: Step S3 also includes smoothing the edge mesh of the merged crown mesh.

4. The method of claim 1, wherein: In step S4, CBCT is expanded based on the boundary point data of the adjacent surfaces of the crown, so that the CBCT fits the crown.

5. A cavity filling system for proximal surfaces of tooth crowns based on CBCT data, characterized in that: include: At least one processor; as well as At least one memory communicatively connected to the processor; The memory stores instructions that can be executed by a processor, which are executed by the processor to cause the electronic device to perform the method for filling cavities on the proximal surface of a tooth crown based on CBCT data, as described in any one of claims 1-4.

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