Undercut processing method based on mesh model

Abstract

An embodiment of the present invention provides a method for processing undercuts based on a mesh model. The method for processing undercuts based on a mesh model includes: pre-processing the triangular mesh surface data of the tooth model to obtain first mesh surface data; performing undercut processing on the first mesh surface data according to preset rules to obtain second mesh surface data; performing triangulation processing on the second mesh surface data to obtain a second mesh surface topology map; fusing the first mesh surface data and the second mesh surface topology map to obtain the tooth model data after undercut processing. Through the above steps, the undercut part of the guide plate in the tooth model can be screened out, and then the guide plate model can be reconstructed based on the screened mesh surface, so that the guide plate after the undercut processing can be smoothly worn on the teeth without being stuck and keeps fit with the teeth.

Description

Technical Field

[0001] The embodiments of the present invention relate to the field of dental implants, and in particular to a method for processing undercuts based on a grid model. Background Art

[0002] Dental implants involve implanting an artificial tooth root into the alveolar bone, then attaching a porcelain tooth over the artificial root. This restoration is identical in function and aesthetics to a natural tooth. The dental implant procedure includes a preoperative examination, implant placement, abutment installation, and crown installation. After the preoperative examination, a plaster model and scan data of the patient's teeth are obtained. This scan data allows for an accurate understanding of the patient's dental condition and the development of a surgical plan. The implant surgery assistance software uses the scan data to accurately determine the implant's position. A surgical guide is then generated based on all relevant information about the tooth and implant.

[0003] However, when generating auxiliary guides for dental implant surgery, due to the very complex morphology of the human oral cavity, the auxiliary guides for dental implant surgery must be able to be smoothly inserted into the teeth without getting stuck, and must fit the teeth as closely as possible and not shake after being worn by the patient. This requires a series of complex processing of the patient's oral data. Summary of the Invention

[0004] In view of this, an embodiment of the present invention provides an undercut processing method based on a grid model to at least partially solve the above problem.

[0005] According to a first aspect of an embodiment of the present invention, a method for processing undercuts based on a mesh model is provided, comprising: preprocessing triangular mesh surface data of a tooth model to obtain first mesh surface data; performing undercut processing on the first mesh surface data according to preset rules to obtain second mesh surface data; triangulating the second mesh surface data to obtain a second mesh surface topology map; and fusing the first mesh surface data and the second mesh surface topology map to obtain tooth model data after undercut processing.

[0006] In another implementation of the present invention, the preprocessing of the triangular mesh surface data of the tooth model to obtain the first mesh surface data includes: acquiring the triangular mesh surface data of the tooth model; and processing the triangular mesh surface data according to the guide plate positioning direction to obtain the first mesh surface data.

[0007] In another implementation of the present invention, the triangular mesh surface data is processed according to the guide plate positioning direction to obtain the first mesh surface data, including: establishing a spatial rectangular coordinate system according to the guide plate positioning direction, wherein the guide plate positioning direction is the negative direction of the Z-axis of the spatial rectangular coordinate system; calculating the correspondence between the spatial rectangular coordinate system and the triangular mesh surface data; and calculating the spatial rectangular coordinates of the triangular mesh surface according to the correspondence to obtain the first mesh surface data.

[0008] In another implementation of the present invention, the first mesh surface data is subjected to undercut processing according to preset rules to obtain second mesh surface data, including: calculating the angle value between the outer normal of the triangular surface in the first mesh surface data and the guide plate positioning direction; screening out the triangular surface corresponding to the angle value that meets the first rule to obtain the second mesh surface data.

[0009] In another implementation of the present invention, the method further includes: calculating a set of rays starting from the vertex coordinates of the triangular surface in the first mesh surface data and emitted in a direction parallel to the guide plate; screening out the triangular surfaces corresponding to the ray set that meet the second rule to obtain the second mesh surface data.

[0010] In another implementation of the present invention, the triangulation processing of the second mesh surface data to obtain a second mesh surface topology map includes: calculating the boundary contour line corresponding to the first mesh surface data based on the first mesh surface data; calculating the projection of the second mesh surface data along the Z-axis of the spatial rectangular coordinate system to obtain second mesh surface projection data; triangulating the second mesh surface projection data to obtain a second mesh surface projection map; and calculating the second mesh surface topology map based on the boundary contour line and the second mesh surface projection map.

[0011] In another implementation of the present invention, the second mesh surface topology map is calculated based on the boundary contour line and the second mesh surface projection subdivision map, including: determining the centroid position of the triangular face in the second mesh surface projection subdivision map; screening out the triangular face in the second mesh surface projection subdivision map corresponding to the centroid position being inside the boundary contour line, to obtain the second mesh surface topology map.

[0012] According to a second aspect of an embodiment of the present invention, a mesh model-based undercut processing device is provided, comprising: a preprocessing module for preprocessing triangular mesh surface data of a tooth model to obtain first mesh surface data; an undercut processing module for performing undercut processing on the first mesh surface data according to preset rules to obtain second mesh surface data; a subdivision processing module for performing triangulation processing on the second mesh surface data to obtain a second mesh surface topology map; and a fusion processing module for performing fusion processing on the first mesh surface data and the second mesh surface topology map to obtain tooth model data after undercut processing.

[0013] According to a third aspect of an embodiment of the present invention, an electronic device is provided, comprising: a processor, a memory, a communication interface and a communication bus, wherein the processor, the memory and the communication interface communicate with each other via the communication bus; the memory is used to store at least one executable instruction, and the executable instruction enables the processor to perform an operation corresponding to the method described in the first aspect.

[0014] According to a fourth aspect of an embodiment of the present invention, a computer storage medium is provided, on which a computer program is stored. When the program is executed by a processor, the method according to the first aspect is implemented.

[0015] In the solution of the embodiment of the present invention, when generating an auxiliary guide for dental implant surgery, since the human oral morphology is very complex, the auxiliary guide for dental implant surgery must be able to be smoothly worn on the teeth without being stuck, and must fit the teeth as closely as possible, and not shake after being worn by the patient, so the concave part of the guide needs to be processed. First, the triangular mesh surface data of the tooth model is pre-processed to obtain the first mesh surface data; then the first mesh surface data is subjected to concave processing according to a preset rule to obtain the second mesh surface data; the second mesh surface data is triangulated to obtain the second mesh surface topology map; finally, the first mesh surface data and the second mesh surface topology map are fused to obtain the tooth model data after the concave processing. Through the above steps, the concave part of the guide plate in the tooth model can be screened out, and then the guide plate model can be reconstructed based on the screened mesh surface, so that the guide plate after the concave processing can be smoothly worn on the teeth, without being stuck, and keeps fitting with the teeth. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments recorded in the embodiments of the present invention. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0017] Figure 1 An exemplary guide plate model generation method is shown.

[0018] Figure 2A The figure is a flowchart of the steps of a method for processing undercuts based on a grid model according to an embodiment of the present invention.

[0019] Figure 2B Schematic diagram of a method for processing undercuts based on a grid model according to an embodiment of the present invention.

[0020] Figure 2C Schematic diagram of a method for processing undercuts based on a grid model according to an embodiment of the present invention.

[0021] Figure 2D Schematic diagram of a method for processing undercuts based on a grid model according to an embodiment of the present invention.

[0022] Figure 2E Schematic diagram of a method for processing undercuts based on a grid model according to an embodiment of the present invention.

[0023] Figure 2F Schematic diagram of a method for processing undercuts based on a grid model according to an embodiment of the present invention.

[0024] Figure 3 4 is a schematic block diagram of an undercut processing apparatus based on a grid model according to an embodiment of the present invention.

[0025] Figure 4 FIG. 1 is a schematic structural diagram of an electronic device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0026] In order to enable those skilled in the art to better understand the technical solutions in the embodiments of the present invention, the technical solutions in the embodiments of the present invention will be clearly and detailedly described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. All other embodiments obtained by those skilled in the art based on the embodiments in the embodiments of the present invention should fall within the scope of protection of the embodiments of the present invention.

[0027] It should be understood that the terms "first," "second," and "third," etc. in the claims, specification, and drawings of this disclosure are used to distinguish different objects rather than to describe a specific order. The terms "include" and "comprising" used in the specification and claims of this disclosure indicate the presence of the described features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or combinations thereof.

[0028] It should also be understood that the terminology used in this disclosure is for the purpose of describing specific embodiments only and is not intended to limit the disclosure. As used in this disclosure and the claims, the singular forms "a," "an," and "the" are intended to include the plural forms unless the context clearly indicates otherwise. It should be further understood that the term "and / or" as used in this disclosure and the claims refers to any and all possible combinations of one or more of the associated listed items, including and including these combinations.

[0029] Figure 1 An exemplary guide plate model generation method is shown. Specifically, an oral scanner is used to obtain three-dimensional surface image data of a patient's oral cavity and establish a virtual oral cavity model; three-dimensional image data of the alveolar bone and three-dimensional image data of the tooth root are obtained, and a virtual alveolar bone model and a virtual tooth root model are established; a virtual guide plate model is generated based on the virtual oral cavity model; the relative positions of the virtual guide plate model, the virtual alveolar bone model and the virtual tooth root model are fixed; according to the positions of the virtual alveolar bone model and the virtual tooth root model, a virtual guide through-hole model is established on the virtual guide plate model, and the three-dimensional image data of the virtual guide plate model is output; and an orthodontic implant support guide plate with a guide through-hole is prepared based on the three-dimensional image data of the virtual guide plate model.

[0030] The above method can generate a tooth guide, but the guide cannot be smoothly inserted into the teeth and may be stuck by the tooth undercut.

[0031] Figure 2A The exemplary process of the undercut processing method based on the grid model according to one embodiment of the present invention is shown. The undercut processing method based on the grid model according to this embodiment includes:

[0032] S210: Preprocessing the triangular mesh surface data of the tooth model to obtain first mesh surface data.

[0033] It should be noted that the triangular mesh surface data of the tooth model here refers to the tooth model data composed of triangular mesh surfaces obtained by performing a three-dimensional scan on the teeth.

[0034] S220: Performing undercut processing on the first mesh surface data according to a preset rule to obtain second mesh surface data.

[0035] It should be noted that the undercut processing here refers to retaining the triangular meshes in the first mesh surface that meet the preset rules, and removing the triangular meshes in the first mesh surface that do not meet the preset rules.

[0036] S230: Perform triangulation processing on the second mesh surface data to obtain a second mesh surface topology graph.

[0037] It should be noted that since the triangular mesh in the first mesh surface that does not meet the preset rules is eliminated, in order to ensure that the guide plate model completely covers the teeth, the mesh of the second mesh surface after elimination needs to be reconstructed. Therefore, the second mesh surface after elimination needs to be triangulated.

[0038] S240: Fusing the first mesh surface data and the second mesh surface topology map to obtain tooth model data after undercut processing.

[0039] It should be noted that, since the second mesh surface topology map is two-dimensional data, the first mesh surface data and the second mesh surface topology map data need to be fused to obtain a three-dimensional data guide plate model.

[0040] In the solution of the embodiment of the present invention, when generating an auxiliary guide for dental implant surgery, since the human oral morphology is very complex, the auxiliary guide for dental implant surgery must be able to be smoothly worn on the teeth without being stuck, and must fit the teeth as closely as possible, and not shake after being worn by the patient, so the concave part of the guide needs to be processed. First, the triangular mesh surface data of the tooth model is pre-processed to obtain the first mesh surface data; then the first mesh surface data is subjected to concave processing according to a preset rule to obtain the second mesh surface data; the second mesh surface data is triangulated to obtain the second mesh surface topology map; finally, the first mesh surface data and the second mesh surface topology map are fused to obtain the tooth model data after the concave processing. Through the above steps, the concave part of the guide plate in the tooth model can be screened out, and then the guide plate model can be reconstructed based on the screened mesh surface, so that the guide plate after the concave processing can be smoothly worn on the teeth, without being stuck, and keeps fitting with the teeth.

[0041] In a possible implementation, the preprocessing of the triangular mesh surface data of the tooth model to obtain the first mesh surface data includes: acquiring the triangular mesh surface data of the tooth model; and processing the triangular mesh surface data according to the guide plate positioning direction to obtain the first mesh surface data.

[0042] It should be noted that if Figure 2B As shown, the positioning direction here refers to the direction in which the guide plate is inserted or removed. For example, to quickly process the first mesh surface, the triangular mesh surface data of the tooth model needs to be pre-processed. This triangular mesh surface data of the tooth model is recalculated according to the positioning direction of the guide plate to obtain the first mesh surface data. This method can effectively improve the efficiency of subsequent processing of the first mesh surface.

[0043] In one possible implementation, the triangular mesh surface data is processed according to the guide plate positioning direction to obtain the first mesh surface data, including: establishing a spatial rectangular coordinate system according to the guide plate positioning direction, wherein the guide plate positioning direction is the negative direction of the Z axis of the spatial rectangular coordinate system; calculating the correspondence between the spatial rectangular coordinate system and the triangular mesh surface data; and calculating the spatial rectangular coordinates of the triangular mesh surface according to the correspondence to obtain the first mesh surface data.

[0044] It should be noted that if Figure 2C As shown, in order to process the first mesh surface more quickly, a spatial rectangular coordinate system can be constructed with the guide plate placement direction as the negative direction of the Z axis of the spatial rectangular coordinate system. The triangular mesh surface data of the tooth model can then be converted to obtain the first mesh surface data in the spatial rectangular coordinate system. This method can improve mesh surface processing efficiency.

[0045] In one possible implementation, the first mesh surface data is concavely processed according to a preset rule to obtain the second mesh surface data, including: calculating the angle value between the outer normal of the triangular surface in the first mesh surface data and the positioning direction of the guide plate; screening out the triangular surface corresponding to the angle value that meets the first rule to obtain the second mesh surface data.

[0046] It should be noted that if Figure 2D As shown, due to the existence of undercuts on the teeth, when processing the first mesh surface data according to the guide plate positioning direction, the triangular surface where the undercut part is located in the first mesh surface data needs to be removed. To this end, the angle value between the outer normal of the triangular surface in the first mesh surface data and the guide plate positioning direction can be calculated, and then the triangular surface corresponding to the angle value that meets the first rule can be screened out.

[0047] Specifically, the first rule means that when the angle between the outer normal of the triangular face in the first mesh surface data and the guide plate positioning direction is greater than 90 degrees, it is retained, otherwise it is filtered out. In this way, the undercut part can be quickly filtered out.

[0048] In one possible implementation, the method further includes: calculating a set of rays starting from the vertex coordinates of the triangular surface in the first mesh surface data and emitted in a direction parallel to the guide plate; screening out the triangular surfaces corresponding to the ray set that meet the second rule to obtain the second mesh surface data.

[0049] It should be noted that in order to more comprehensively filter out the concave parts, a set of rays starting from the vertex coordinates of the triangular surface in the first mesh surface data and emitted in a direction parallel to the guide plate can be calculated, and then the triangular surface corresponding to the spatial vector that meets the second rule can be screened out.

[0050] Specifically, the second rule refers to calculating three rays starting from the three vertex coordinates of the triangular face in the first mesh surface data and emitted in a direction parallel to the guide plate. When none of the three rays have a spatial intersection with other triangular faces in the first mesh surface, the triangular face is retained, otherwise it is filtered out.

[0051] Preferably, the first grid surface data is subjected to undercut processing according to a first rule and a second rule to obtain second grid surface data.

[0052] In one possible implementation, the triangulation processing of the second mesh surface data to obtain a second mesh surface topology map includes: calculating a boundary contour line corresponding to the first mesh surface data based on the first mesh surface data; calculating a projection of the second mesh surface data along the Z-axis of the spatial rectangular coordinate system to obtain second mesh surface projection data; triangulating the second mesh surface projection data to obtain a second mesh surface projection map; and calculating a second mesh surface topology map based on the boundary contour line and the second mesh surface projection map.

[0053] It should be noted that if Figure 2E As shown, the boundary contour line corresponding to the first mesh surface data can be calculated based on the topological relationship between the triangular faces in the first mesh surface data, and the boundary contour line here only coincides with one edge of the triangular face in the first mesh surface data. Calculating the projection of the second mesh surface data along the Z axis of the spatial rectangular coordinate system here refers to calculating the projection of the second mesh surface data on the xOy plane of the spatial rectangular coordinate system. The triangulation processing of the second mesh surface projection data here can be processing the second mesh surface projection data according to the Delaunay rule to obtain a second mesh surface topology map with a topological relationship. In this way, the guide plate model can be reconstructed in the early stage of filtering out the undercut part of the guide plate.

[0054] In one possible implementation, the second mesh surface topology map is calculated based on the boundary contour line and the second mesh surface projection subdivision map, including: determining the centroid position of the triangular face in the second mesh surface projection subdivision map; screening out the triangular face in the second mesh surface projection subdivision map corresponding to the centroid position being inside the boundary contour line, to obtain the second mesh surface topology map.

[0055] It should be noted that if Figure 2F As shown in the figure, since redundant triangular faces are generated when calculating the second mesh surface topology, the redundant triangular faces can be retained or filtered out by determining whether the centroid of the triangular face is within the boundary contour line. In this way, the guide plate model can be reconstructed while filtering out the undercut portion of the guide plate.

[0056] Preferably, the number of intersections between the triangle's centroid and the edges of the triangle can be used to determine whether the triangle's centroid is inside the boundary contour line. If the number of intersections between the triangle's centroid and any edge of the triangle is an odd number, the triangle's centroid is inside the boundary contour line. If the number of intersections between the triangle's centroid and any edge of the triangle is an even number, the triangle's centroid is outside the boundary contour line.

[0057] Figure 3 FIG2 is a schematic block diagram of an undercut processing device based on a grid model according to another embodiment of the present invention. The solution of the embodiment of the present invention can be applied to electronic devices, including but not limited to: terminal devices with communication functions or electronic devices with interactive behavior capabilities.

[0058] The mesh model-based undercut processing device of this embodiment includes: a preprocessing module for preprocessing the triangular mesh surface data of the tooth model to obtain first mesh surface data; an undercut processing module for performing undercut processing on the first mesh surface data according to preset rules to obtain second mesh surface data; a subdivision processing module for performing triangulation processing on the second mesh surface data to obtain a second mesh surface topology map; and a fusion processing module for performing fusion processing on the first mesh surface data and the second mesh surface topology map to obtain the tooth model data after undercut processing.

[0059] In other examples, the pre-processing module is specifically used to: obtain triangular mesh surface data of the tooth model;

[0060] The triangular mesh surface data is processed according to the guide plate positioning direction to obtain first mesh surface data.

[0061] In other examples, the preprocessing module is specifically used to: establish a spatial rectangular coordinate system based on the guide plate positioning direction, wherein the guide plate positioning direction is the negative direction of the Z axis of the spatial rectangular coordinate system; calculate the correspondence between the spatial rectangular coordinate system and the triangular mesh surface data; calculate the spatial rectangular coordinates of the triangular mesh surface based on the correspondence to obtain the first mesh surface data.

[0062] In other examples, the undercut processing module is specifically used to: calculate the angle value between the outer normal of the triangular surface in the first mesh surface data and the guide plate positioning direction; filter out the triangular surfaces corresponding to the angle value that meets the first rule to obtain the second mesh surface data.

[0063] In other examples, the undercut processing module is specifically used to: calculate a set of rays starting from the vertex coordinates of the triangular surface in the first mesh surface data and emitted in a direction parallel to the guide plate; filter out the triangular surfaces corresponding to the ray set that meet the second rule to obtain the second mesh surface data.

[0064] In other examples, the subdivision processing module is specifically used to: calculate the boundary contour line corresponding to the first grid surface data based on the first grid surface data; calculate the projection of the second grid surface data along the Z axis of the spatial rectangular coordinate system to obtain the second grid surface projection data; perform triangulation processing on the second grid surface projection data to obtain a second grid surface projection subdivision diagram; and calculate the second grid surface topology diagram based on the boundary contour line and the second grid surface projection subdivision diagram.

[0065] In other examples, the subdivision processing module is specifically used to: determine the centroid position of the triangular face in the second mesh surface projection subdivision diagram; filter out the triangular face in the second mesh surface projection subdivision diagram corresponding to the centroid position being inside the boundary contour line, and obtain a second mesh surface topology diagram.

[0066] Reference Figure 4 , shows a schematic structural diagram of an electronic device according to another embodiment of the present invention. The specific embodiment of the present invention does not limit the specific implementation of the electronic device.

[0067] like Figure 4 As shown, the electronic device may include: a processor (processor) 402 , a communication interface (Communications Interface) 404 , a memory (memory) 406 storing a program 410 , and a communication bus 408 .

[0068] The processor, communication interface, and memory communicate with each other via a communication bus. The communication interface is used to communicate with other electronic devices or servers. The processor is used to execute a program, specifically, the steps of the above-described method embodiments. Specifically, the program may include program code, which includes computer operating instructions.

[0069] The processor may be a CPU, an ASIC (Application Specific Integrated Circuit), or one or more integrated circuits configured to implement the embodiments of the present invention. The one or more processors included in the smart device may be processors of the same type, such as one or more CPUs, or processors of different types, such as one or more CPUs and one or more ASICs.

[0070] Memory is used to store programs. The memory may include high-speed RAM memory, and may also include non-volatile memory (non-volatile memory), such as at least one disk storage.

[0071] The program can be specifically used to enable the processor to perform the following operations: pre-process the triangular mesh surface data of the tooth model to obtain first mesh surface data; perform undercut processing on the first mesh surface data according to preset rules to obtain second mesh surface data; perform triangulation processing on the second mesh surface data to obtain a second mesh surface topology map; and fuse the first mesh surface data and the second mesh surface topology map to obtain the tooth model data after undercut processing.

[0072] The above embodiments are only used to illustrate the embodiments of the present invention, and are not intended to limit the embodiments of the present invention. Ordinary technicians in the relevant technical field can make various changes and modifications without departing from the spirit and scope of the embodiments of the present invention. Therefore, all equivalent technical solutions also fall within the scope of the embodiments of the present invention, and the scope of patent protection of the embodiments of the present invention should be defined by the claims. The systems, devices, modules or units described in the above embodiments can be implemented by computer chips or entities, or by products with certain functions.

[0073] For the convenience of description, the above device is described as being divided into various units according to their functions. Of course, when implementing the present invention, the functions of each unit can be implemented in the same or multiple software and / or hardware.

[0074] It will be understood by those skilled in the art that embodiments of the present invention may be provided as methods, systems, or computer program products. Thus, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0075] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowcharts and / or block diagrams, as well as combinations of processes and / or blocks in the flowcharts and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowcharts and / or block diagrams. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0076] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0077] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0078] In a typical configuration, a computing device includes one or more processors (CPUs), input / output interfaces, network interfaces, and memory. Memory may include non-permanent storage in a computer-readable medium, such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM. Memory is an example of a computer-readable medium.

[0079] Computer-readable media includes permanent and non-permanent, removable and non-removable media that can be implemented by any method or technology to store information. The information can be computer-readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disc read-only memory (CD-ROM), digital versatile disc (DVD) or other optical storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer-readable media does not include transitory computer-readable media (transitory media), such as modulated data signals and carrier waves.

[0080] It should also be noted that the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, commodity, or apparatus that includes a series of elements includes not only those elements but also other elements not explicitly listed, or includes elements inherent to such process, method, commodity, or apparatus. In the absence of further limitations, an element defined by the phrase "comprises a ..." does not exclude the presence of other identical elements in the process, method, commodity, or apparatus that includes the element.

[0081] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Thus, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0082] The present invention may be described in the general context of computer-executable instructions, such as program modules, executed by a computer. Generally, program modules include routines, programs, objects, components, data structures, and the like that perform specific tasks or implement specific abstract data types. The present invention may also be practiced in distributed computing environments where tasks are performed by remote processing devices connected via a communications network. In a distributed computing environment, program modules may be located in both local and remote computer storage media, including storage devices.

[0083] The various embodiments in this specification are described in a progressive manner. Similar parts between the various embodiments can be referred to in conjunction with each other. Each embodiment focuses on the differences between the other embodiments. In particular, the system embodiments are generally similar to the method embodiments, so the description is relatively simple. For relevant parts, refer to the description of the method embodiments.

Claims

1. A method for processing undercuts based on a grid model, comprising: Preprocessing the triangular mesh surface data of the tooth model to obtain first mesh surface data; Performing concave processing on the first mesh surface data according to a preset rule to obtain second mesh surface data; Performing triangulation processing on the second mesh surface data to obtain a second mesh surface topology graph; Fusing the first mesh surface data and the second mesh surface topology map to obtain tooth model data after undercut processing; The preprocessing of the triangular mesh surface data of the tooth model to obtain the first mesh surface data includes: Obtain triangular mesh surface data of the tooth model; Processing the triangular mesh surface data according to the guide plate positioning direction to obtain first mesh surface data; The processing of the triangular mesh surface data according to the guide plate positioning direction to obtain first mesh surface data includes: Establishing a spatial rectangular coordinate system according to the guide plate positioning direction, wherein the guide plate positioning direction is the negative direction of the Z axis of the spatial rectangular coordinate system; Calculating the correspondence between the spatial rectangular coordinate system and the triangular mesh surface data; Calculate the spatial rectangular coordinates of the triangular mesh surface according to the corresponding relationship to obtain first mesh surface data; The step of performing concave processing on the first mesh surface data according to a preset rule to obtain second mesh surface data includes: Calculating the angle between the outer normal of the triangle surface in the first mesh surface data and the guide plate positioning direction; The triangular faces corresponding to the angle values ​​that meet the first rule are screened out to obtain second mesh surface data.

2. The method according to claim 1, wherein The method further comprises: Calculating a ray set starting from the vertex coordinates of the triangular surface in the first mesh surface data and emitted in a direction parallel to the guide plate; The triangular faces corresponding to the ray set that meet the second rule are screened out to obtain second mesh surface data.

3. The method according to claim 2, wherein: The triangulating the second mesh surface data to obtain a second mesh surface topology graph includes: Calculating a boundary contour line corresponding to the first grid surface data according to the first grid surface data; Calculating a projection of the second grid surface data along the Z axis of the spatial rectangular coordinate system to obtain second grid surface projection data; Performing triangulation processing on the second mesh surface projection data to obtain a second mesh surface projection triangulation graph; A second mesh surface topology map is calculated based on the boundary contour line and the second mesh surface projection subdivision map.

4. The method according to claim 3, wherein: The step of calculating a second mesh surface topology map based on the boundary contour line and the second mesh surface projection subdivision map includes: Determining the centroid position of the triangular face in the second mesh surface projection subdivision graph; The triangular faces in the second mesh surface projection subdivision graph corresponding to the centroid position being inside the boundary contour line are screened out to obtain a second mesh surface topology graph.

5. A device for processing undercuts based on a grid model, comprising: A preprocessing module, configured to preprocess the triangular mesh surface data of the tooth model to obtain first mesh surface data; an undercut processing module, configured to perform undercut processing on the first mesh surface data according to a preset rule to obtain second mesh surface data; a triangulation processing module, configured to perform triangulation processing on the second mesh surface data to obtain a second mesh surface topology graph; a fusion processing module, configured to fuse the first mesh surface data and the second mesh surface topology map to obtain tooth model data after undercut processing; The preprocessing of the triangular mesh surface data of the tooth model to obtain the first mesh surface data includes: Obtain triangular mesh surface data of the tooth model; Processing the triangular mesh surface data according to the guide plate positioning direction to obtain first mesh surface data; The processing of the triangular mesh surface data according to the guide plate positioning direction to obtain first mesh surface data includes: Establishing a spatial rectangular coordinate system according to the guide plate positioning direction, wherein the guide plate positioning direction is the negative direction of the Z axis of the spatial rectangular coordinate system; Calculating the correspondence between the spatial rectangular coordinate system and the triangular mesh surface data; Calculate the spatial rectangular coordinates of the triangular mesh surface according to the corresponding relationship to obtain first mesh surface data; The step of performing concave processing on the first mesh surface data according to a preset rule to obtain second mesh surface data includes: Calculating the angle between the outer normal of the triangle surface in the first mesh surface data and the guide plate positioning direction; The triangular faces corresponding to the angle values ​​that meet the first rule are screened out to obtain second mesh surface data.

6. An electronic device comprising: A processor, a memory, a communication interface, and a communication bus, wherein the processor, the memory, and the communication interface communicate with each other via the communication bus; The memory is used to store at least one executable instruction, and the executable instruction enables the processor to perform an operation corresponding to the method according to any one of claims 1 to 4.

7. A computer storage medium having a computer program stored thereon, wherein when the program is executed by a processor, the method according to any one of claims 1 to 4 is implemented.

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