Accessory avoidance method, device, medium and equipment for filling undercuts in digital tooth models

Abstract

The present invention provides an accessory avoidance method, device, medium and equipment for filling undercuts in a digital tooth model, the method comprising obtaining a digital tooth model; obtaining an accessory model and an undercut model of an adjacent tooth according to the digital tooth model; performing collision calculation on the undercut model and the accessory model, calculating the shortest distance between the undercut model and the accessory model, and determining a collision detection result between the undercut model and the accessory model according to the shortest distance; after determining that the undercut model and the accessory model will collide according to the collision detection result, setting a virtual component model at the center of the accessory according to the shape of the accessory model; performing a difference processing between the virtual component model and the undercut model to obtain a target undercut model. The present invention can automatically avoid accessories in the process of generating an undercut grid, thereby reducing the cost of manual restoration.

Description

Technical Field

[0001] The present invention relates to the technical field of tooth correction, and in particular to an accessory avoidance method, device, medium and equipment for filling undercuts in a digital tooth model. Background Art

[0002] Orthodontics mainly uses force for correction, and the braces are a device for treating malocclusion that can generate force. The braces mainly include fixed braces and invisible braces. Fixed braces are an important type of orthodontic appliance. This type of appliance is fixed to the teeth by adhesion or ligation. Fixed braces have good retention, sufficient support, are suitable for applying various types of corrective forces, and are conducive to the movement of most teeth. They can effectively control the direction of tooth movement. Invisible braces can be freely removed and put on by patients or doctors. When removed, the appliance is intact. It relies on the retention of the clasp and the adsorption of the mucosa to exert its corrective effect. Doctors can add or remove accessories that can generate corrective force on the appliance as needed to achieve the purpose of correcting malocclusion. Invisible braces are favored by more and more customers due to their beautiful and convenient features.

[0003] In the process of designing invisible braces, a digital model of the teeth is generally obtained based on the teeth of the target object. When the jaw plane is horizontal, the tooth will have an inclined angle, which will make the tooth protrude from the gums. The projection of the frontmost part of the tooth is located in front of the gums, and there will be a triangular space between the tooth and the gums. This space is called an undercut. In the digital model of the tooth, the undercut area is generally filled. However, in the process of filling the undercut area with the undercut filling grid, since there is a need to design accessories in the correction plan of the dental appliance, and the existing undercut filling method does not take into account the influence of the accessories, when encountering the overlap between the undercut filling grid and the accessories, it is directly chosen not to automatically fill the undercut, but to use manual repair to fill the undercut, which makes the filling process complicated, and the manual repair method will also affect the filling grid.

[0004] Therefore, it is necessary to provide a new type of accessory avoidance method, device, medium and equipment for filling undercuts in digital tooth models to solve the above-mentioned problems existing in the prior art. Summary of the invention

[0005] The object of the present invention is to provide a method, device, medium and equipment for avoiding accessories for filling undercuts in a digital tooth model, which can automatically avoid accessories while generating a grid for filling undercuts.

[0006] In a first aspect, to achieve the above-mentioned purpose, the attachment avoidance method for filling undercuts in a digital tooth model of the present invention comprises:

[0007] Get digital models of teeth;

[0008] Acquire an accessory model according to the digital tooth model, and acquire a position of the tooth corresponding to the accessory model according to the position of the accessory model on the digital tooth model;

[0009] Acquire the undercut model of the corresponding tooth and adjacent teeth according to the position of the tooth corresponding to the accessory model;

[0010] Performing collision calculation on the undercut model and the accessory model, calculating the shortest distance between the undercut model and the accessory model, and determining a collision detection result between the undercut model and the accessory model according to the shortest distance;

[0011] After determining, according to the collision detection result, that the undercut model will collide with the accessory model, setting a virtual component model at the center position of the accessory according to the shape of the accessory model;

[0012] The virtual component model and the undercut model are subjected to a difference processing to obtain a target undercut model.

[0013] The beneficial effect of the accessory avoidance method for filling undercuts in a digital tooth model described in the present invention is that after obtaining a digital tooth model, the accessory model and the position of the corresponding teeth are obtained according to the digital tooth model, so that the adjacent teeth and the undercut models of the adjacent teeth are obtained according to the positions of the corresponding teeth, and then the collision calculation is performed on the undercut model and the accessory model, and after determining that the undercut model and the accessory model will collide, a virtual component model is set at the center position of the accessory according to the shape of the accessory model, and the virtual component model is subtracted from the undercut model to obtain the target undercut model, thereby completing the optimization and adjustment process of the undercut model, so that the target undercut model finally obtained can automatically avoid the accessories, avoiding the inconvenience caused by manual repair of the undercut model.

[0014] Optionally, setting a virtual component model at a center position of the accessory according to the shape of the accessory includes:

[0015] Obtaining a bounding box of the accessory model in the local coordinate system of the digital tooth model;

[0016] Calculate the diagonal length of the bounding box, set the virtual component model to an inverted frustum, the radius of the first bottom surface of the inverted frustum is the diagonal length, the radius of the second bottom surface of the inverted frustum is half of the diagonal length, and the height of the inverted frustum is the diagonal length;

[0017] The rotation axis direction of the frustum table is set to be along the demoulding direction of the corresponding tooth, and the center of the frustum table is set at the center position of the attachment to complete the setting of the virtual component model. The beneficial effect is that the virtual component model is set in the above manner so that when the undercut model is subsequently subjected to difference processing by the virtual component model, the virtual component model can completely cover the area of ​​the attachment model to ensure that the target undercut model obtained subsequently will not collide with the attachment in the digital tooth model.

[0018] Optionally, the bounding box is an axisymmetric bounding box or a directed bounding box.

[0019] Optionally, performing a difference process between the virtual component model and the undercut model to obtain a target undercut model includes:

[0020] Obtaining an overlapping area between the virtual component model and the undercut model through a mesh Boolean operation, and taking the overlapping area as the difference result;

[0021] The target undercut model is obtained after the overlapping area is removed from the undercut model. The beneficial effect is that the target undercut model is obtained after the overlapping area is removed from the undercut model, so as to avoid collision between the target undercut model and the accessories.

[0022] Optionally, determining the collision detection result between the undercut model and the attachment model according to the shortest distance includes:

[0023] Determine the difference between the shortest distance and a preset threshold;

[0024] When the shortest distance is greater than the preset threshold, it is determined that the undercut model and the attachment model will not collide;

[0025] When the shortest distance is less than or equal to the preset threshold, it is determined that the undercut model will collide with the attachment model.

[0026] Optionally, the shortest distance is a distance between a triangular mesh of the attachment model and a triangular mesh of the undercut filling model calculated by using an inter-mesh shortest distance algorithm.

[0027] In a second aspect, the present invention further provides an accessory avoidance device for filling undercuts in a digital tooth model, comprising:

[0028] A tooth model acquisition module is used to acquire a digital tooth model;

[0029] An attachment acquisition module, used to acquire an attachment model according to the digital tooth model, and acquire a position of the tooth corresponding to the attachment model according to the position of the attachment model on the digital tooth model;

[0030] An undercut acquisition module, used for acquiring an undercut model of the corresponding tooth and adjacent teeth according to the position of the tooth corresponding to the accessory model;

[0031] a collision judgment module, used for performing collision calculation on the undercut model and the accessory model, calculating the shortest distance between the undercut model and the accessory model, and determining a collision detection result between the undercut model and the accessory model according to the shortest distance;

[0032] An adding module is used for setting a virtual component model at the center position of the accessory according to the shape of the accessory model after determining that the undercut model will collide with the accessory model according to the collision detection result;

[0033] The optimization processing module is used to perform a difference processing between the virtual component model and the undercut filling model to obtain a target undercut filling model.

[0034] The beneficial effect of the accessory avoidance device for filling undercuts in a digital tooth model described in the present invention is that: after the tooth model acquisition module acquires the digital tooth model, the accessory acquisition module acquires the accessory model and the position of the corresponding tooth according to the digital tooth model, so as to acquire the adjacent teeth according to the position of the corresponding teeth, and obtains the undercut model of the adjacent teeth through the undercut acquisition module, and then the collision judgment module performs collision calculation on the undercut model and the accessory model, and after determining that the undercut model and the accessory model will collide, a virtual component model is set at the center position of the accessory according to the shape of the accessory model, and the optimization processing module performs difference processing on the virtual component model and the undercut model to obtain the target undercut model, thereby completing the optimization and adjustment process of the undercut model, so that the target undercut model finally obtained can automatically avoid the accessories, avoiding the inconvenience caused by manual repair of the undercut model.

[0035] Optionally, the adding module is further used for:

[0036] Obtaining a bounding box of the accessory model in the local coordinate system of the digital tooth model;

[0037] Calculate the diagonal length of the bounding box, set the virtual component model to an inverted frustum, the radius of the first bottom surface of the inverted frustum is the diagonal length, the radius of the second bottom surface of the inverted frustum is half of the diagonal length, and the height of the inverted frustum is the diagonal length;

[0038] The rotation axis direction of the frustum table is set to be along the demoulding direction of the corresponding tooth, and the center of the frustum table is set at the center position of the attachment to complete the setting of the virtual component model.

[0039] In a third aspect, the present invention further provides a computer storage medium, comprising computer instructions, which, when executed on an electronic device, enables the electronic device to execute the above-mentioned accessory avoidance method for filling undercuts in a digital tooth model.

[0040] In a fourth aspect, the present invention further provides an electronic device, comprising a processor and a memory, wherein the processor executes computer instructions stored in the memory, so that the electronic device executes the above-mentioned accessory avoidance method for filling undercuts in a digital tooth model. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 A flow chart of an accessory avoidance method for filling undercuts in a digital tooth model according to an embodiment of the present invention;

[0042] Figure 2 A schematic flow chart of the method for avoiding attachments for filling undercuts in a digital tooth model according to an embodiment of the present invention, which includes setting a virtual component model at the center of the attachment according to the shape of the attachment;

[0043] Figure 3 It is a schematic diagram of adjusting the attachment avoidance method for filling undercuts in a digital tooth model according to an embodiment of the present invention;

[0044] Figure 4 This is a structural block diagram of an accessory avoidance device for filling undercuts in a digital tooth model according to an embodiment of the present invention. DETAILED DESCRIPTION

[0045] In order to make the purpose, technical solutions and advantages of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Unless otherwise defined, the technical terms or scientific terms used herein should be understood by people with general skills in the field to which the present invention belongs. "Including" and similar words used in this article mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects.

[0046] In view of the problems existing in the prior art, an embodiment of the present invention provides an accessory avoidance method for filling undercuts in a digital tooth model, such as Figure 1 As shown, the following steps are included:

[0047] S101, obtaining a digital tooth model.

[0048] The digital tooth model is obtained based on the tooth data of the target object, and the digital tooth model also includes various accessory models.

[0049] S102: Acquire an accessory model according to the digital tooth model, and acquire a position of the tooth corresponding to the accessory model according to the position of the accessory model on the digital tooth model.

[0050] After obtaining the digital tooth model, in order to avoid the subsequent undercut model, firstly, each accessory model is obtained according to the digital tooth model, and the position of the tooth corresponding to the accessory model is obtained according to the position of the accessory model on the digital tooth model, that is, the position of the tooth related to the accessory model, so as to quickly confirm the position of the undercut model and facilitate the subsequent optimization of the undercut model according to the accessory model.

[0051] S103, obtaining an undercut model of the corresponding tooth and adjacent teeth according to the position of the tooth corresponding to the accessory model.

[0052] After obtaining the position of the tooth corresponding to the accessory model, the undercut model can be established according to the position of the corresponding tooth.

[0053] Specifically, when the accessory model is located on a single tooth digital model, the current tooth digital model and its adjacent tooth digital model are used as a tooth digital model pair, and the undercut model is established according to the tooth digital model pair.

[0054] In some embodiments, the process of establishing an undercut model based on the digital tooth model includes:

[0055] The two tooth digital models in the current tooth digital model pair are respectively recorded as tooth model one and tooth model two. After determining tooth model one and tooth model two, the center points of the tooth digitized grids of tooth model one and tooth model two are obtained, and recorded as the first center point and the second center point respectively. Then, the first center point and the second center point are connected together with a straight line, and the center position of the straight line connecting the first center point and the second center point is used as the center of the sampling circle, and the plane perpendicular to the line connecting the first center point and the second center point is used as the plane where the sampling circle is located. Then, according to the preset radius, a complete sampling circle can be obtained, and then a set of sampling points are obtained by uniformly sampling on the circumference of the sampling circle.

[0056] In this embodiment, the number of the group of sampling points is 30, and the group of sampling points is sampled uniformly and equidistantly on the circumference of the sampling circle to ensure that the group of sampling points obtained by sampling is not too concentrated to affect the accuracy of the final result.

[0057] After obtaining the group of sampling points, the distances between each vertex of the dental digitized grid of the dental model one and each sampling point, as well as the distances between each vertex of the dental digitized grid of the dental model two are calculated respectively, and the vertices with the smallest distances among the vertices of the dental digitized grid of the first dental model are taken as a group of corresponding points, and the vertices with the smallest distances among the vertices of the dental digitized grid of the second dental model are taken as a group of corresponding points, thereby selecting a group of corresponding points on the dental model one and the dental model two, respectively.

[0058] In this embodiment, since the number of sampling points is 30, the number of two groups of corresponding points acquired on the tooth model 1 and the tooth model 2 is 30 each.

[0059] After respectively acquiring the set of corresponding points on tooth model one and tooth model two, several sets of interpolation circle points are added between the two sets of corresponding points, wherein the interpolation circle points include a circle of interpolation points, and then the interpolation points in the interpolation circle points are respectively connected with the two sets of corresponding points through triangular meshes to form an undercut model, thereby completing the process of establishing the undercut model.

[0060] It should be noted that this solution does not involve the optimization of the process of establishing the undercut model. The process of obtaining the undercut model in this solution can be obtained by the above process or by other methods. This solution does not make any special limitations on this and will not be repeated here.

[0061] S104, performing collision calculation on the undercut model and the accessory model, calculating the shortest distance between the undercut model and the accessory model, and determining a collision detection result between the undercut model and the accessory model according to the shortest distance.

[0062] Since collision detection is required for the accessory model and the undercut model, collision detection is performed on the accessory model and the undercut model by detecting the shortest distance, and the collision detection result is determined according to the size of the shortest distance.

[0063] In some embodiments, determining the collision detection result between the undercut model and the accessory model according to the shortest distance includes:

[0064] Determine the difference between the shortest distance and a preset threshold;

[0065] When the shortest distance is greater than the preset threshold, it is determined that the undercut model and the attachment model will not collide;

[0066] When the shortest distance is less than or equal to the preset threshold, it is determined that the undercut model will collide with the attachment model.

[0067] The preset threshold satisfies the following formula:

[0068]

[0069] Among them, L represents the preset threshold, h represents the thickness of the dental appliance diaphragm, N represents the number of layers of the dental appliance diaphragm, and B represents the initial deviation value. While determining the preset distance according to the thickness and number of layers of the dental appliance diaphragm, the preset distance is also optimized by the initial deviation value to effectively reduce the error of the preset distance, thereby ensuring that the result of judging whether a collision will occur between the first collision detection object and the second collision detection object by the size of the shortest distance and the preset distance is more accurate.

[0070] The above method is used to perform collision detection on the accessory model and the undercut model, so as to adjust the undercut mesh according to the collision detection result, so that the undercut mesh can automatically avoid the accessory model.

[0071] In some embodiments, the shortest distance is the distance between the triangular mesh of the attachment model and the triangular mesh of the undercut filling model calculated by an inter-mesh shortest distance algorithm.

[0072] Specifically, the above process includes: first, respectively obtaining the triangular mesh of the accessory model and the triangular mesh of the filling-in-undercut model, then obtaining the centroid of the triangular mesh of the accessory model and the centroid of the triangular mesh of the filling-in-undercut model, and using the centroid line between the centroid of the triangular mesh of the accessory model and the centroid of the triangular mesh of the filling-in-undercut model as the separation axis, respectively calculating the projections of the grid points of the triangular mesh of the accessory model and the grid points of the triangular mesh of the filling-in-undercut model on the separation axis, and calculating the overlapping length between the projections of the grid points of the triangular mesh of the accessory model and the projections of the triangular mesh of the filling-in-undercut model, so that the overlapping length can be used as the shortest distance between the triangular mesh of the accessory model and the triangular mesh of the filling-in-undercut model.

[0073] S105 , after determining, according to the collision detection result, that the undercut model will collide with the accessory model, setting a virtual component model at the center position of the accessory according to the shape of the accessory model.

[0074] In some embodiments, the virtual component model is set at the center position of the accessory according to the shape of the accessory, such as Figure 2 As shown, the following steps are included:

[0075] S201, obtaining a bounding box of the accessory model in the local coordinate system of the digital tooth model;

[0076] S202, calculating the diagonal length of the bounding box, setting the virtual component model to an inverted frustum, the radius of the first bottom surface of the inverted frustum is the diagonal length, the radius of the second bottom surface of the inverted frustum is half of the diagonal length, and the height of the inverted frustum is the diagonal length;

[0077] S203, setting the rotation axis direction of the frustum table to be along the demoulding direction of the corresponding tooth, setting the center of the frustum table at the center position of the attachment, and completing the setting of the virtual component model.

[0078] Specifically, firstly, a bounding box of the accessory model in the local coordinate system of the digital tooth model is obtained, wherein the bounding box is an axisymmetric bounding box or a directed bounding box. In the present embodiment, the bounding box is an axisymmetric bounding box.

[0079] After obtaining the bounding box of the accessory model in the digital tooth model, the diagonal length A of the bounding box is calculated, and the virtual component model is set to a frustum, wherein the radius of the first bottom surface of the frustum is the diagonal length A, the radius of the second bottom surface is half the diagonal length A / 2, and the height of the frustum is the diagonal length A, thereby obtaining the complete parameters of the virtual component model, and then obtaining the demolding direction of the corresponding tooth and the center position of the accessory, and the corresponding tooth is the demolding direction of the tooth in the digital tooth model, thereby setting the rotation axis direction of the frustum to the demolding direction along the corresponding tooth, and setting the center position of the frustum at the center position of the accessory, and determining the position of the entire frustum in the digital tooth model based on the rotation axis direction, center position, height, radius of the first bottom surface, and radius of the second bottom surface of the frustum, thereby completing the setting process of the virtual component model.

[0080] The center position of the frustum is the midpoint of the line segment where the height of the frustum in the direction of the rotation axis is located.

[0081] S106: Perform a difference process between the virtual component model and the undercut model to obtain a target undercut model.

[0082] In some embodiments, the above process includes:

[0083] Obtaining an overlapping area between the virtual component model and the undercut model through a mesh Boolean operation, and taking the overlapping area as the difference result;

[0084] After removing the overlapping area from the undercut filling model, a target undercut filling model is obtained.

[0085] Specifically, after obtaining the virtual component model and the undercut model, the overlapping area between the virtual component model and the undercut model is obtained through mesh Boolean operation and the overlapping area is used as the difference result. After removing the difference result in the undercut model, the adjustment process of the undercut model can be completed, thereby obtaining the target undercut model, so that the target undercut model will not interfere with the accessory model, and the target undercut model can automatically avoid the accessory. The mesh schematic diagram of the undercut model is shown in FIG. Figure 3 shown.

[0086] The present invention also provides an accessory avoidance device for filling undercuts in a digital tooth model, such as Figure 4 As shown, including:

[0087] A tooth model acquisition module 401 is used to acquire a digital tooth model;

[0088] The attachment acquisition module 402 is used to acquire the attachment model according to the digital tooth model, and acquire the position of the tooth corresponding to the attachment model according to the position of the attachment model on the digital tooth model;

[0089] An undercut acquisition module 403 is used to acquire an undercut model of the corresponding tooth and adjacent teeth according to the position of the tooth corresponding to the accessory model;

[0090] A collision judgment module 404 is used to perform collision calculation on the undercut model and the accessory model, calculate the shortest distance between the undercut model and the accessory model, and determine a collision detection result between the undercut model and the accessory model according to the shortest distance;

[0091] An adding module 405 is used to set a virtual component model at the center position of the accessory according to the shape of the accessory model after determining that the undercut model will collide with the accessory model according to the collision detection result;

[0092] The optimization processing module 406 is used to perform a difference processing between the virtual component model and the undercut model to obtain a target undercut model.

[0093] In some embodiments, the adding module is further used to:

[0094] Obtaining a bounding box of the accessory model in the local coordinate system of the digital tooth model;

[0095] Calculate the diagonal length of the bounding box, set the virtual component model to an inverted frustum, the radius of the first bottom surface of the inverted frustum is the diagonal length, the radius of the second bottom surface of the inverted frustum is half of the diagonal length, and the height of the inverted frustum is the diagonal length;

[0096] The rotation axis direction of the frustum table is set to be along the demoulding direction of the corresponding tooth, and the center of the frustum table is set at the center position of the attachment to complete the setting of the virtual component model.

[0097] It should be noted that the structure and principle of the accessory avoidance device for filling undercuts in the above-mentioned digital tooth model correspond one to one with the steps in the accessory avoidance method for filling undercuts in the above-mentioned digital tooth model, so they will not be repeated here.

[0098] It should be noted that it should be understood that the division of the various modules of the above device is only a division of logical functions. In actual implementation, they can be fully or partially integrated into one physical entity, or they can be physically separated. And these modules can all be implemented in the form of software calling through processing elements; they can also be all implemented in the form of hardware; some modules can also be implemented in the form of software calling through processing elements, and some modules can be implemented in the form of hardware. For example, the selection module can be a separately established processing element, or it can be integrated in a certain chip of the above system for implementation. In addition, it can also be stored in the memory of the above system in the form of program code, and called and executed by a certain processing element of the above system. The implementation of other modules is similar. In addition, these modules can be fully or partially integrated together, or they can be implemented independently. The processing element described here can be an integrated circuit with signal processing capabilities. In the implementation process, each step of the above method or each module above can be completed by an integrated logic circuit of hardware in the processor element or instructions in the form of software.

[0099] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the embodiment of the present application is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) or a processor to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: various media that can store program codes, such as flash memory, mobile hard disk, read-only memory, random access memory, disk or optical disk.

[0100] Through the description of the above implementation methods, technicians in the relevant field can clearly understand that for the convenience and simplicity of description, only the division of the above functional modules is used as an example. In actual applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the device is divided into different functional modules to complete all or part of the functions described above. The specific working process of the system, device and unit described above can refer to the corresponding process in the aforementioned method embodiment, and will not be repeated here.

[0101] Each functional unit in each embodiment of the present application can be integrated into a processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The above integrated unit can be implemented in the form of hardware or in the form of software functional units.

[0102] The present invention also provides a computer storage medium, including computer instructions, which, when executed on an electronic device, enables the electronic device to execute the above-mentioned accessory avoidance method for filling undercuts in a digital tooth model. The storage medium includes: a read-only memory (ROM), a random access memory (RAM), a disk, a USB flash drive, a memory card, or an optical disk, and other media that can store program codes.

[0103] The present invention also provides an electronic device, comprising a processor and a memory, wherein the processor executes computer instructions stored in the memory, so that the electronic device executes the above-mentioned accessory avoidance method for filling undercuts in a digital tooth model.

[0104] Although the embodiments of the present invention are described in detail above, it is obvious to those skilled in the art that various modifications and variations can be made to these embodiments. However, it should be understood that such modifications and variations are within the scope and spirit of the present invention as described in the claims. Moreover, the present invention described herein may have other embodiments and may be implemented or realized in a variety of ways.

Claims

1. A method for avoiding attachments when filling undercuts in a digital tooth model, characterized in that: include: Get digital models of teeth; Acquire an accessory model according to the digital tooth model, and acquire a position of the tooth corresponding to the accessory model according to the position of the accessory model on the digital tooth model; Acquire the undercut model of the corresponding tooth and adjacent teeth according to the position of the tooth corresponding to the accessory model; Performing collision calculation on the undercut model and the accessory model, calculating the shortest distance between the undercut model and the accessory model, obtaining a judgment result according to the shortest distance and a preset threshold, and determining a collision detection result between the undercut model and the accessory model according to the judgment result; After determining, according to the collision detection result, that the undercut model will collide with the accessory model, setting a virtual component model at the center position of the accessory according to the shape of the accessory model; The virtual component model and the undercut model are subjected to a difference processing to obtain a target undercut model.

2. The method for avoiding attachments for filling undercuts in a digital tooth model according to claim 1, characterized in that: The step of setting a virtual component model at a center position of the accessory according to the shape of the accessory comprises: Obtaining a bounding box of the accessory model in the local coordinate system of the digital tooth model; Calculate the diagonal length of the bounding box, set the virtual component model to an inverted frustum, the radius of the first bottom surface of the inverted frustum is the diagonal length, the radius of the second bottom surface of the inverted frustum is half of the diagonal length, and the height of the inverted frustum is the diagonal length; The rotation axis direction of the frustum table is set to be along the demoulding direction of the corresponding tooth, and the center of the frustum table is set at the center position of the attachment to complete the setting of the virtual component model.

3. The method for avoiding attachments for filling undercuts in a digital tooth model according to claim 2, characterized in that: The bounding box is an axisymmetric bounding box or a directed bounding box.

4. The method for avoiding attachments for filling undercuts in a digital tooth model according to claim 2, characterized in that: The step of performing a difference process between the virtual component model and the undercut model to obtain a target undercut model includes: Obtaining an overlapping area between the virtual component model and the undercut model through a mesh Boolean operation, and taking the overlapping area as the difference result; After removing the overlapping area from the undercut filling model, a target undercut filling model is obtained.

5. The method for avoiding attachments for filling undercuts in a digital tooth model according to claim 2, characterized in that: The step of determining the collision detection result between the undercut model and the attachment model according to the shortest distance includes: Determine the difference between the shortest distance and a preset threshold; When the shortest distance is greater than the preset threshold, it is determined that the undercut model and the attachment model will not collide; When the shortest distance is less than or equal to the preset threshold, it is determined that the undercut model will collide with the attachment model.

6. The method for avoiding attachments for filling undercuts in a digital tooth model according to claim 5, characterized in that: The shortest distance is the distance between the triangular mesh of the attachment model and the triangular mesh of the undercut filling model calculated by the shortest distance algorithm between meshes.

7. An accessory avoidance device for filling undercuts in a digital tooth model, characterized in that: include: A tooth model acquisition module is used to acquire a digital tooth model; An attachment acquisition module, used to acquire an attachment model according to the digital tooth model, and acquire a position of the tooth corresponding to the attachment model according to the position of the attachment model on the digital tooth model; An undercut acquisition module, used for acquiring an undercut model of the corresponding tooth and adjacent teeth according to the position of the tooth corresponding to the accessory model; a collision judgment module, used for performing collision calculation on the undercut model and the accessory model, calculating the shortest distance between the undercut model and the accessory model, obtaining a judgment result according to the shortest distance and a preset threshold, and determining a collision detection result between the undercut model and the accessory model according to the judgment result; An adding module is used for setting a virtual component model at the center position of the accessory according to the shape of the accessory model after determining that the undercut model will collide with the accessory model according to the collision detection result; The optimization processing module is used to perform a difference processing between the virtual component model and the undercut filling model to obtain a target undercut filling model.

8. The accessory avoidance device for filling undercuts in a digital tooth model according to claim 7, characterized in that: The adding module is also used for: Obtaining a bounding box of the accessory model in the local coordinate system of the digital tooth model; Calculate the diagonal length of the bounding box, set the virtual component model to an inverted frustum, the radius of the first bottom surface of the inverted frustum is the diagonal length, the radius of the second bottom surface of the inverted frustum is half of the diagonal length, and the height of the inverted frustum is the diagonal length; The rotation axis direction of the frustum table is set to be along the demoulding direction of the corresponding tooth, and the center of the frustum table is set at the center position of the attachment to complete the setting of the virtual component model.

9. A computer storage medium, characterized in that The method comprises computer instructions, which, when executed on an electronic device, enable the electronic device to execute the accessory avoidance method for filling undercuts in a digital tooth model as claimed in any one of claims 1 to 6.

10. An electronic device, characterized in that: The electronic device comprises a processor and a memory, wherein the processor executes computer instructions stored in the memory, so that the electronic device executes the accessory avoidance method for filling undercuts in a digital tooth model as described in any one of claims 1 to 6.

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