A three-dimensional modeling system and method for a dental restoration

Abstract

The application provides a kind of prosthesis three-dimensional modeling system and method, the geometric topology of the boundary of the preparation body of prosthesis and the direction of the target preparation body are used to construct initial crown inner crown face, and then the main tip geometric characteristics of the occlusal surface form of the opposite tooth are determined;Dynamic occlusion data of opposite tooth and adjacent tooth form are obtained, and then the non-median slip component of mandibular movement trajectory in the dynamic occlusion data of opposite tooth and the contour curvature of adjacent area contour line in the adjacent tooth form are extracted;The functional occlusal surface of prosthesis is morphologically constrained according to the non-median slip component, the contour curvature of adjacent area contour line and the main tip geometric characteristics, and the occlusal surface three-dimensional model is obtained;The texture compensation is carried out on the occlusal surface three-dimensional model based on the material compensation coefficient of prosthesis, and the complete three-dimensional prosthesis model is output.Based on the above scheme, the fusion driven modeling of occlusion data and adjacent tooth form in prosthesis can be realized.

Description

Technical Field

[0001] This application relates to the field of three-dimensional modeling technology, and more specifically, to a three-dimensional modeling system and method for dental prostheses. Background Technology

[0002] Dental prostheses are oral devices made of artificial materials used to repair or replace damaged or missing natural teeth, restoring their anatomical shape, chewing efficiency, speech function, and facial aesthetics. Depending on the scope and design of the restoration, the main types include inlays, crowns, bridges, and implant superstructures. Modern prostheses are generally designed and manufactured using digital processes to ensure precise morphological fit and stable long-term efficacy.

[0003] Current digital design technologies for dental prostheses generally rely on single-positional jaw relationship data to construct occlusal surfaces, simplifying the complex three-dimensional movements of the mandible into a static spatial alignment. The resulting occlusal surface morphology can only guarantee a match with the anatomical morphology of the opposing teeth in a specific jaw position. However, the oral masticatory system is a dynamic functional whole. The mandible needs to perform various movements such as protrusion, lateralization, and opening and closing during daily functional activities. Its movement trajectory is controlled by the temporomandibular joint, ligaments, and muscles, exhibiting highly individualized characteristics. Occlusal surfaces designed solely based on static jaw positions cannot anticipate or accommodate problems such as premature contact, functional interference, or lack of movement guidance that may occur between the mandible and the prosthesis during non-centric movements. This directly leads to frequent jaw adjustments during clinical fitting and may cause risks such as decreased long-term prosthesis success rates, abnormal abutment tooth load, and even temporomandibular joint disorders. Therefore, how to achieve integrated modeling of occlusal data and adjacent tooth morphology in dental prostheses to improve the functional fit of prostheses within the oral cavity has become a challenge for the industry. Summary of the Invention

[0004] This application provides a three-dimensional modeling system and method for oral prostheses, which can realize the fusion-driven modeling of occlusal data and adjacent tooth morphology in oral prostheses, thereby improving the functional fit of oral prostheses in the oral cavity.

[0005] Firstly, this application provides a method for three-dimensional modeling of dental prostheses, including: A digital model of the target preparation body and the opposing tooth in the oral cavity is obtained, and the edge line of the digital model is fitted to obtain the preparation body boundary of the oral prosthesis. The initial inner coronal surface of the tooth crown is constructed by the geometric topology of the boundary of the prepared body and the direction of the path of placement of the target prepared body. The occlusal surface morphology of the opposing tooth crown is determined according to the initial inner coronal surface of the tooth crown and the preset occlusal space rules, thereby obtaining the cusp geometric features of the occlusal surface morphology of the tooth crown. The dynamic occlusal data of the opposing teeth and the morphology of adjacent teeth are obtained. Then, the non-centric sliding component of the mandibular movement trajectory in the dynamic occlusal data of the opposing teeth and the curvature of the line connecting the contour points of the adjacent area in the morphology of the adjacent teeth are extracted. Based on the non-centric sliding component, the curvature of the line connecting the contour points of the adjacent area and the geometric features of the principal cusp, the morphological constraints of the functional occlusal surface of the oral prosthesis are applied to obtain a three-dimensional model of the occlusal surface. Texture compensation is performed on the occlusal surface 3D model based on the material compensation coefficient of the dental prosthesis to output a complete 3D prosthesis model.

[0006] In some embodiments, edge-line fitting of the digital model to obtain the pre-body boundary of the dental prosthesis specifically includes: The digital model is segmented by region growth to separate the surface of the prepared body from the surface of the gingival tissue, and the segmentation boundary is used as the initial set of edge points. The normal vector and curvature of each edge point in the initial edge point set are calculated, and outliers caused by scanning noise are filtered out to obtain the preparatory body boundary of the oral prosthesis.

[0007] In some embodiments, constructing the initial inner coronal surface of the crown through the geometric topology of the preparation body boundary and the placement path direction of the target preparation body specifically includes: Based on the geometric topology of the prepared body boundary, the region enclosed by the prepared body boundary line is identified as the inner coronal surface base. The base surface of the inner crown substrate is offset at equal intervals by means of the placement path of the target preparation body to obtain the initial inner crown surface.

[0008] In some embodiments, the occlusal surface morphology of the opposing tooth crown is determined based on the initial inner coronal surface and a preset occlusal space rule, thereby obtaining the principal cusp geometric features of the occlusal surface morphology, specifically including: Based on the digital model of the opposing tooth, a misalignment envelope space representing the range of motion of the opposing tooth at the maximum cusp intersection position is constructed outside the inner coronal surface of the initial crown. An initial occlusal surface is generated within the misaligned envelope space, which is connected to the inner crown surface and does not penetrate the opposing tooth; The apex of the functional cusp is identified and located in the initial occlusal surface, and the three-dimensional coordinates of each functional cusp apex and the direction vector of the principal cusp ridge at the connection with the inner coronal surface are extracted to obtain the principal cusp geometric features of the occlusal surface morphology of the crown.

[0009] In some embodiments, extracting the non-centric slip component of the mandibular motion trajectory in the dynamic occlusion data of the opposing teeth and the curvature of the line connecting the contour points of the adjacent tooth morphology specifically includes: The mandibular motion trajectory in the dynamic occlusion data of opposing teeth is decomposed into a centric closure path and a non-centric glide path. The projection vector and distance of the non-centric glide path on each motion plane are calculated as the non-centric glide component. On the digital model of the adjacent tooth, the contact area adjacent to the target restoration is determined, and multiple contour points along the gingival direction within the contact area are extracted; Curve fitting is performed on all contour points, and the average curvature and Gaussian curvature of the fitted curve in three-dimensional space are calculated as the curvature of the line connecting adjacent contour points.

[0010] In some embodiments, the morphological constraints on the functional occlusal surface of the dental prosthesis are applied based on the non-centric slip component, the curvature of the line connecting the contour points of the adjacent area, and the geometric features of the principal cusp, to obtain a three-dimensional model of the occlusal surface, specifically including: Initialize the objective function for occlusal surface optimization, which includes a non-central slip constraint term, an adjacent curvature matching term, and a primary cusp geometry preservation term; Starting from the initial occlusal surface, the positions of the vertices of the occlusal surface mesh are adjusted iteratively by gradient to minimize the objective function, thereby obtaining the three-dimensional model of the occlusal surface.

[0011] In some embodiments, texture compensation is performed on the occlusal surface 3D model based on the material compensation coefficient of the dental prosthesis to output a complete 3D prosthesis model, specifically including: Based on the selected manufacturing process and materials for the prosthesis, obtain the material compensation coefficient for the dental prosthesis; Along the normal direction of the outer surface of the occlusal surface three-dimensional model, the texture isometry scaling and local offset compensation are performed on the occlusal surface three-dimensional model according to the material compensation coefficient to obtain a complete three-dimensional restoration model.

[0012] Secondly, this application provides a three-dimensional modeling system for dental prostheses, comprising: The acquisition module is used to acquire digital models of the target preparation body and the opposing tooth in the oral cavity, and to perform edge line fitting on the digital model to obtain the preparation body boundary of the oral prosthesis. The processing module is used to construct an initial inner coronal surface of the tooth crown through the geometric topology of the boundary of the prepared body and the direction of the path of placement of the target prepared body, determine the occlusal surface morphology of the opposing tooth crown according to the initial inner coronal surface of the tooth crown and the preset occlusal space rules, and then obtain the cusp geometric features of the occlusal surface morphology of the tooth crown. The processing module is also used to acquire dynamic occlusal data of opposing teeth and morphology of adjacent teeth, and then extract the non-centric sliding component of the mandibular movement trajectory in the dynamic occlusal data of opposing teeth and the curvature of the line connecting the contour points of the adjacent area in the morphology of adjacent teeth. Based on the non-centric sliding component, the curvature of the line connecting the contour points of the adjacent area and the geometric features of the principal cusp, the functional occlusal surface of the oral prosthesis is morphologically constrained to obtain a three-dimensional model of the occlusal surface. The execution module is used to perform texture compensation on the occlusal surface 3D model based on the material compensation coefficient of the oral prosthesis, and output a complete 3D prosthesis model.

[0013] Thirdly, this application provides a computer device, which includes a memory and a processor. The memory is used to store a computer program, and the processor is used to call and run the computer program from the memory, so that the computer device performs the above-described three-dimensional modeling method for dental prostheses.

[0014] Fourthly, this application provides a computer-readable storage medium storing instructions or code that, when executed on a computer, cause the computer to implement the above-described three-dimensional modeling method for dental prostheses.

[0015] The technical solutions provided by the embodiments disclosed in this application have the following beneficial effects: This application provides a three-dimensional modeling system and method for oral prostheses, which involves acquiring digital models of the target pre-prosthesis and the opposing tooth, fitting edge lines to the digital models to obtain the pre-prosthesis boundary; constructing an initial inner crown surface using the geometric topology of the pre-prosthesis boundary and the insertion path direction of the target pre-prosthesis; determining the occlusal surface morphology of the opposing tooth crown based on the initial inner crown surface and preset occlusal space rules, thereby obtaining the cusp geometry of the occlusal surface morphology; acquiring dynamic occlusal data of the opposing tooth and the morphology of adjacent teeth; extracting the non-centric slip component of the mandibular movement trajectory from the dynamic occlusal data of the opposing tooth and the curvature of the contour lines connecting the adjacent teeth; constraining the functional occlusal surface of the oral prosthesis based on the non-centric slip component, the curvature of the contour lines connecting the adjacent teeth, and the cusp geometry to obtain a three-dimensional occlusal surface model; and performing texture compensation on the three-dimensional occlusal surface model based on the material compensation coefficient of the oral prosthesis to output a complete three-dimensional prosthesis model.

[0016] Therefore, in this application, texture compensation is performed on the three-dimensional model of the occlusal surface based on the material compensation coefficient of the oral prosthesis to output a complete three-dimensional prosthesis model. First, by determining the geometric features of the principal cusp of the occlusal surface morphology, the anatomical framework of the occlusal functional surface of the prosthesis can be obtained. The geometric features of the principal cusp quantify the three-dimensional spatial coordinates of the functional cusp and the orientation vector of the principal cusp ridge, constituting the basic parameter set of occlusal surface morphology. This ensures that the final generated occlusal surface maintains basic physiological anatomical structure while meeting dynamic functional requirements. By establishing a benchmark model that is highly consistent with the morphology of natural teeth, the biological rationality of the prosthesis morphology is guaranteed, laying the necessary structural foundation for its stable occlusal contact and force transmission in the mouth. Then, by determining the three-dimensional model of the functional occlusal surface, a model that simultaneously satisfies dynamic occlusal function and adjacent relationship can be obtained. The final occlusal surface constrained by the system is achieved by integrating the dynamic motion trajectory constraints represented by the non-centric slip component, the static adjacency relationship matching represented by the curvature of the adjacency zone, and the basic morphology represented by the geometry of the main cusp into a unified mathematical optimization framework. This drives the evolution of the occlusal surface morphology from static anatomical simulation to dynamic functional adaptation. It not only ensures precise alignment with the opposing tooth at the maximum cusp intersection position, but also provides smooth and interference-free functional motion guidance during non-centric movements such as mandibular protrusion and lateral movements. At the same time, it forms a stable and reasonable contact relationship with adjacent teeth, thereby improving the overall adaptability and long-term stability of the restoration in the complex oral functional environment. In summary, based on the above scheme, the fusion-driven modeling of occlusal data and adjacent tooth morphology in oral restorations can be realized, thereby improving the functional adaptability of oral restorations in the oral cavity. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is an exemplary flowchart of a three-dimensional modeling method for oral prostheses according to some embodiments of this application; Figure 2 This is a flowchart illustrating the process of determining a three-dimensional model of the occlusal surface according to some embodiments of this application; Figure 3 This is a structural schematic diagram of a three-dimensional modeling system for dental prostheses according to some embodiments of this application; Figure 4 This is a schematic diagram of the structure of a computer device for implementing a three-dimensional modeling method for dental prostheses according to some embodiments of this application. Detailed Implementation

[0019] To better understand the technical solution of this application, the technical solution of this application will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0020] refer to Figure 1 The figure is an exemplary flowchart of a three-dimensional modeling method for oral prostheses according to some embodiments of this application. The three-dimensional modeling method for oral prostheses mainly includes the following steps: In step 101, digital models of the target preparatory body and the opposing tooth in the oral cavity are obtained, and edge lines are fitted to the digital models to obtain the preparatory body boundary of the oral prosthesis.

[0021] It should be noted that, in this application, the target preparation digital model is a set of three-dimensional surface data representing the tooth to be restored after dental preparation and having a specified geometric shape; the opposing tooth digital model is a set of three-dimensional surface data representing the opposing teeth or dentition that have occlusal contact with the target preparation.

[0022] In practice, firstly, an intraoral scanner is used to optically scan the target tooth position in the patient's oral cavity to obtain three-dimensional point cloud data of the prepared body surface; the point cloud is converted into a continuous surface model using a triangular meshing algorithm, and a surface filtering algorithm is used to remove scanning noise; the processed mesh model is used as input data for subsequent edge line fitting; then, when the patient is in the maximum cusp intersection position, an intraoral scanner is used to collect three-dimensional morphological data of the opposing dentition; multiple scan segments are aligned to the same coordinate system using a coordinate registration algorithm to form a complete opposing dental arch model; this model is used as the benchmark data for occlusal relationship analysis and occlusal space construction.

[0023] In some embodiments, edge-line fitting of the digital model to obtain the prepared body boundary of the dental prosthesis can be achieved by the following steps: The digital model is segmented by region growth to separate the surface of the prepared body from the surface of the gingival tissue, and the segmentation boundary is used as the initial set of edge points. The normal vector and curvature of each edge point in the initial edge point set are calculated, and outliers caused by scanning noise are filtered out to obtain the preparatory body boundary of the oral prosthesis.

[0024] It should be noted that, in this application, region growth segmentation is a computational method used to divide the target preparation digital model into different sub-regions based on its surface geometric features or curvature differences; the preparation surface is a three-dimensional surface geometry representing the hard tooth tissue after being cut; the gingival tissue surface is a three-dimensional surface geometry representing the soft tissue contour surrounding the tooth; the normal vector is a unit vector describing the orientation of the three-dimensional model surface at a specified point; curvature is a numerical scalar used to quantify the degree of curvature of the three-dimensional model surface at a certain point; outliers are data points that deviate significantly from the true edge in terms of geometric features due to noise interference during the scanning process.

[0025] In specific implementation, firstly, the digital model is segmented by region growth to separate the preparation surface and the gingival tissue surface. The initial edge point set is used as the segmentation boundary. This can be achieved by manually selecting one or more seed points on the hard tissue of the preparation in the digital model of the target preparation. Starting from the seed points, based on geometric similarity criteria such as the angle between the normal vector of the seed point and the adjacent triangular facet being less than a set threshold and curvature continuity, adjacent facets are iteratively merged into the same region. The above process is repeated until no facets meet the merging conditions. The model is divided into regions representing the hard tissue of the preparation and regions representing the soft tissue of the gingiva. The set of mesh vertices at the boundary of the two regions is extracted as the initial edge point set. Then, the normal vector and curvature of each edge point in the initial edge point set are calculated, and outliers caused by scanning noise are filtered out to obtain the preparation boundary of the oral prosthesis. This can be achieved by calculating the weighted average of the normal vectors of its adjacent triangular facets for each vertex in the initial edge point set. Curvature is calculated based on the coordinates of the vertex and all vertices in its ring neighborhood. The principal curvature at that point is estimated through local surface fitting (e.g., fitting a quadratic surface), resulting in Gaussian or average curvature. After calculation, the curvature values ​​of all edge points are statistically analyzed. Points whose curvature values ​​deviate from the median curvature of the entire point set by more than a certain number of standard deviations (e.g., three times) are identified as outliers caused by scanning noise and filtered out. The edge point set after filtering out outliers is used as the preliminary volume boundary.

[0026] In step 102, an initial inner coronal surface of the tooth crown is constructed by the geometric topology of the boundary of the prepared body and the direction of the path of placement of the target prepared body. The occlusal surface morphology of the opposing tooth crown is determined according to the initial inner coronal surface of the tooth crown and the preset occlusal space rules, thereby obtaining the cusp geometry of the occlusal surface morphology of the tooth crown.

[0027] In some embodiments, the initial inner coronal surface of the crown can be constructed by means of the geometric topology of the preparation body boundary and the path of insertion of the target preparation body, using the following steps: Based on the geometric topology of the prepared body boundary, the region enclosed by the prepared body boundary line is identified as the inner coronal surface base. The base surface of the inner crown substrate is offset at equal intervals by means of the placement path of the target preparation body to obtain the initial inner crown surface.

[0028] It should be noted that, in this application, the geometric topology of the preparation body boundary is a structural diagram describing the logical relationship between the connection points and spatial arrangement of the preparation body boundary points; the inner coronal surface base is the tooth preparation surface area defined by the preparation body boundary line, used to construct the basic shape of the initial inner coronal surface of the crown; the placement path direction of the target preparation body is a spatial direction vector used to define the placement path of the dental prosthesis; the base surface of the inner coronal surface base is a three-dimensional geometric shape describing the inner coronal surface base as a sub-surface; equidistant offset is a geometric operation used to generate a new surface that maintains a fixed distance from the original surface in the normal direction at all points; the initial inner coronal surface of the crown is a three-dimensional inner surface used to initially characterize the tissue surface fit between the dental prosthesis and the preparation body.

[0029] In specific implementation, firstly, based on the geometric topology of the prepared body boundary, identifying the region enclosed by the prepared body boundary line as the inner crown surface base can be achieved in the following way: the prepared body boundary line is a closed spatial curve connected end to end in three-dimensional space. According to the projection position of this boundary line on the surface of the prepared body digital model, a model surface region completely enclosed by the boundary line can be determined. This region contains all triangular mesh faces extending from the boundary line towards the prepared body's interlocking surface or cutting edge. The set of triangular mesh faces located inside the boundary line and directly or indirectly connected to the boundary line is extracted to form a complete subsurface. This subsurface, defined and surrounded by the preparation boundary line, representing the main supporting surface of the tooth preparation, is identified as the inner coronal surface base. The preparation surface area surrounded by the boundary line is taken as the inner coronal surface base. Then, the base surface of the inner coronal surface base is offset equidistantly by the path of descent of the target preparation. The initial inner coronal surface can be obtained by: determining the path of descent of the target preparation, which is consistent with the average direction of the long axis of the preparation or calculated by the convergence of multiple axial walls of the preparation; and translating each vertex on the base surface of the inner coronal surface base outward (i.e. away from the center of the tooth preparation) by a fixed distance along a single global direction determined by the opposite direction of the path of descent (or more precisely, along the normal vector direction of each triangular facet on the inner coronal surface base). This fixed distance is the sum of the preset compensation values ​​for the thickness of the restoration material and the thickness of the adhesive layer; all the translated new vertices are reconstructed according to the connection relationship of the original triangular mesh to form a new curved surface that is consistent with the original inner crown surface base surface morphology but is expanded and offset outward as a whole. The newly generated curved surface compensates for the inner surface of the restoration in the material space. The new curved surface generated after the equidistant offset operation is used as the initial inner crown surface of the tooth crown.

[0030] In some embodiments, the occlusal surface morphology of the opposing tooth crown is determined based on the initial inner coronal surface and a preset occlusal space rule, and the principal cusp geometry of the occlusal surface morphology is obtained by the following steps: Based on the digital model of the opposing tooth, a misalignment envelope space representing the range of motion of the opposing tooth at the maximum cusp intersection position is constructed outside the inner coronal surface of the initial crown. An initial occlusal surface is generated within the misaligned envelope space, which is connected to the inner crown surface and does not penetrate the opposing tooth; The apex of the functional cusp is identified and located in the initial occlusal surface, and the three-dimensional coordinates of each functional cusp apex and the direction vector of the principal cusp ridge at the connection with the inner coronal surface are extracted to obtain the principal cusp geometric features of the occlusal surface morphology of the crown.

[0031] It should be noted that, in this application, the misalignment envelope space is a three-dimensional spatial range used to define the boundary that can be generated by the initial occlusal surface, which is defined by the extreme position of the opposing tooth on the non-centric movement trajectory; the initial occlusal surface is a three-dimensional curved surface used to preliminarily define the morphology of the occlusal functional surface of the oral prosthesis; the vertex of the functional cusp is the highest point or characteristic point of the cusp that undertakes the main occlusal contact function in three-dimensional geometry; and the direction vector of the principal cusp ridge is the spatial direction describing the direction of the main ridge line extending from the vertex of the functional cusp to the cusp slope.

[0032] In specific implementation, firstly, based on the digital model of the opposing tooth, a misalignment envelope space representing the range of motion of the opposing tooth at the maximum cusp intersection position is constructed outside the inner coronal surface of the initial crown. This can be achieved in the following way: the digital models of the upper and lower jaws are registered and aligned according to the maximum cusp intersection position; based on the mandibular motion trajectory parameters recorded clinically (e.g., hinge axis, protrusion condyle guide angle, lateral condyle guide angle), the digital model of the opposing tooth is driven to perform non-centric movements such as protrusion, retraction, leftward, and rightward movements, and the spatial coordinates of the opposing tooth at each extreme position are recorded; the initial... The set of spatial points that maintain a preset minimum safe distance from the inner crown surface of the initial tooth and the opposing tooth at all these extreme positions; the spatial region occupied by the set of points that satisfy the above distance constraints is calculated and extracted by a three-dimensional convex hull or voxelization algorithm, and the spatial region enclosed by the calculated extreme range of movement of the opposing tooth is taken as the misalignment envelope space; then, an initial occlusal surface that is connected to the inner crown surface and does not penetrate the opposing tooth can be generated in the misalignment envelope space in the following way: the upper boundary line of the inner crown surface of the initial tooth is taken as the starting boundary of the initial occlusal surface. Starting from this boundary line, using a surface scanning or skinning algorithm, new surface boundary rings are generated layer by layer towards the inner top of the misalignment envelope space and filled with triangular meshes. During the generation of each new boundary ring, the distance between points on the ring and the surface of the opposing tooth digital model is detected in real time. If impending penetration is detected, the position of the boundary ring is adjusted in the opposite direction based on the preset minimum occlusal contact thickness, ensuring that the newly generated surface is always within the misalignment envelope space and maintains a uniform gap with the opposing tooth surface equal to at least the minimum occlusal contact thickness. This process is repeated until a smooth, closed occlusal surface is generated that is completely within the misalignment envelope space. This final smooth, closed surface is used as the initial occlusal surface. Finally, the vertices of the functional cusps are identified and located from the initial occlusal surface, and the three-dimensional coordinates of each functional cusp vertex and the connection points with the inner crown surface are extracted. The direction vector of the principal cusp, to obtain the principal cusp geometry of the occlusal surface of the crown, can be achieved in the following way: Calculate the average curvature of each triangular facet vertex on the initial occlusal surface, identify regions with local curvature greater than a set threshold as potential cusp regions, mark the vertex with the largest Z-coordinate (occlusal direction) value as the vertex of the functional cusp within each cusp region, and record its three-dimensional coordinates; starting from this vertex, trace along the path with the largest curvature gradient towards the cusp's lateral slope on the occlusal surface to obtain a spatial curve, calculate the tangent direction of this spatial curve at the vertex of the functional cusp, and this direction is the direction vector of the principal cusp. Repeat this process for all functional cusps of the restoration (e.g., the buccal and lingual cusps of the maxillary molars), and use the set of the three-dimensional coordinates of each functional cusp vertex and its corresponding principal cusp direction vector as the principal cusp geometry.

[0033] In step 103, dynamic occlusal data of the opposing teeth and the morphology of adjacent teeth are acquired. Then, the non-centric slip component of the mandibular movement trajectory in the dynamic occlusal data of the opposing teeth and the curvature of the line connecting the contour points of the adjacent area in the morphology of the adjacent teeth are extracted. Based on the non-centric slip component, the curvature of the line connecting the contour points of the adjacent area and the geometric features of the principal cusp, the morphological constraints of the functional occlusal surface of the oral prosthesis are applied to obtain a three-dimensional model of the occlusal surface.

[0034] In some embodiments, acquiring dynamic occlusal data of opposing teeth and morphology of adjacent teeth can be achieved in the following manner: First, dynamic occlusal data of opposing teeth is collected using a mandibular motion trajectory recorder. The sensors of the recorder are fixed to the patient's maxilla and mandible respectively, and the patient is guided to perform standardized functional movements including protrusion, retraction, leftward movement, rightward movement, and mastication cycle. The tracing device continuously records the three-dimensional spatial coordinate changes of the mandibular sensor relative to the maxillary sensor at a specified sampling frequency (e.g., 100 points per second), thereby obtaining a series of spatial position points arranged in chronological order to form a complete mandibular movement trajectory. The recorded time-space trajectory sequence is used as the dynamic occlusal data of the opposing teeth. Then, using an intraoral scanner, while acquiring the digital model of the target preparation, a three-dimensional scan is performed on the teeth directly adjacent to the preparation (mesial and distal adjacent teeth). The scanning range must completely cover the clinical crown of the adjacent teeth, especially the proximal surface area opposite to the preparation. The point cloud data obtained from the scan is reconstructed into a triangular mesh model, and the model is precisely aligned with the acquired digital model of the target preparation to the same patient coordinate system using coordinate registration technology. The aligned triangular mesh model of the adjacent teeth is used as the morphology of the adjacent teeth.

[0035] It should be noted that, in this application, the dynamic occlusion data of the opposing teeth is used to record the trajectory data of the continuous change of the three-dimensional spatial position of the mandible relative to the maxilla during functional movement over time; the morphology of adjacent teeth is the three-dimensional geometric shape of the teeth adjacent to the target preparation body.

[0036] In some embodiments, extracting the non-centric slip component of the mandibular motion trajectory in the dynamic occlusion data of the opposing teeth and the curvature of the line connecting the contour points of the adjacent tooth morphology can be achieved by the following steps: The mandibular motion trajectory in the dynamic occlusion data of opposing teeth is decomposed into a centric closure path and a non-centric glide path. The projection vector and distance of the non-centric glide path on each motion plane are calculated as the non-centric glide component. On the digital model of the adjacent tooth, the contact area adjacent to the target restoration is determined, and multiple contour points along the gingival direction within the contact area are extracted; Curve fitting is performed on all contour points, and the average curvature and Gaussian curvature of the fitted curve in three-dimensional space are calculated as the curvature of the line connecting adjacent contour points.

[0037] It should be noted that in this application, the non-centric slip component is a mathematical expression used to quantify the displacement and direction of the mandible relative to the reference plane and direction after it leaves the centric relationship during non-centric movement; the contact area is a three-dimensional curved surface region characterizing the surface of the adjacent tooth that is expected to make physical contact with the surface of the target restoration; the contour point is a three-dimensional spatial point on the curve located at the same horizontal height (equal coordinate values ​​in the gingival direction) within the same contact area of ​​the adjacent tooth, used to analyze the morphology of the proximal surface; the curvature of the line connecting the contour points of the proximal area is a numerical measure used to quantify the curvature complexity of the spatial curve fitted by the contour points in three-dimensional space, including the mean curvature and the Gaussian curvature.

[0038] In practice, firstly, the mandibular movement trajectory in the dynamic occlusion data of the opposing teeth is decomposed into a centric closure path and a non-centric glide path. The projection vector and distance of the non-centric glide path on each motion plane are calculated. The non-centric glide component can be implemented as follows: From the acquired dynamic occlusion data of the opposing teeth, identify and extract the mandibular movement segment from the maximum opening position to the maximum cusp intersection position, and define this segment as the centric closure path; identify the lateral and protruding movement trajectories of the mandible after reaching or passing the maximum cusp intersection position, and define these trajectories as non-centric glide paths; establish three orthogonal reference planes, such as the sagittal plane, the coronal plane, and the horizontal plane. For each trajectory point on the non-centric glide path, calculate the distance and direction from its projection point on the sagittal plane to the starting projection point (as the sagittal component), and the distance and direction from its projection point on the coronal plane to the starting projection point. The distance and direction of the point (as a coronal component), and the distance and direction of the projection point to the starting projection point on the horizontal plane (as a horizontal component); these projection distance and direction vectors on different motion planes (e.g., the forward displacement of protrusion movement on the sagittal plane) are summarized and serialized and recorded. The set of projection distances and direction vectors of each motion plane is calculated as the non-centric slip component. Then, the contact area adjacent to the target restoration is determined on the adjacent tooth digital model, and multiple contour points along the gingival direction in the contact area are extracted. This can be achieved in the following way: on the aligned adjacent tooth digital model, according to clinical experience and preset adjacent area position rules, a region is manually or automatically selected. This region is located on the side of the adjacent tooth facing the prepared body, and its gingival range extends from the contact point of the adjacent tooth to 1 mm above the gingival margin, and the mesial and distal range covers about one-third of the crown width. The area selected by this box is defined as the contact area. On the surface of the contact area, a series of horizontal sections are defined at fixed intervals (e.g., 0.5 mm) along the gingival direction (i.e., from the gingival direction to the occlusal direction). The horizontal sections intersect with the three-dimensional curved surface of the contact area, resulting in one or more intersection lines. For each intersection line, the point located at the center of the contact area (e.g., the midpoint of the intersection line in the mesiodistal direction) is selected as a representative point at that height. These representative points at all heights are collected.The extracted spatial points distributed along the gingival-maxillary direction by height are used as multiple contour points. Finally, all contour points are subjected to curve fitting, and the average curvature and Gaussian curvature of the fitted curve in three-dimensional space are calculated. The curvature of the line connecting adjacent contour points can be achieved as follows: using a spatial curve fitting algorithm (e.g., cubic B-spline curve fitting), all the contour points extracted in the previous step are fitted into a smooth three-dimensional spatial curve; the curvature attribute at each point on this fitted curve is calculated based on the principles of differential geometry. Specifically, the curvature attribute at each point on the curve... For each point, calculate its two principal curvature values ​​(i.e., the curvatures corresponding to the maximum and minimum curvatures of the curve at that point); define the arithmetic mean of these two principal curvatures as the average curvature of that point, and define the product of these two principal curvatures as the Gaussian curvature of that point; calculate the average of the average curvatures of all points on the fitted curve as the overall average curvature of the curve, and calculate the average of the Gaussian curvatures of all points on the curve as the overall Gaussian curvature of the curve; use the numerical pair of the overall average curvature and the overall Gaussian curvature of the fitted curve as the curvature of the line connecting the contour points of the adjacent region.

[0039] In some embodiments, the functional occlusal surface of the dental prosthesis is morphologically constrained based on the non-centric slip component, the curvature of the line connecting the contour points of the adjacent area, and the geometric features of the principal cusp, resulting in a three-dimensional model of the occlusal surface, with reference to... Figure 2 The figure described above is a flowchart illustrating the process of determining the three-dimensional model of the occlusal surface in some embodiments of this application. In this embodiment, the determination of the three-dimensional model of the occlusal surface can be achieved by the following steps: In step 1031, the objective function for occlusal surface optimization is initialized, the objective function including non-central slip constraint term, adjacent curvature matching term and primary cusp geometry preservation term; In step 1032, the positions of the vertices of the occlusal surface mesh are adjusted by gradient iteration starting from the initial occlusal surface in order to minimize the objective function and thus obtain the three-dimensional model of the occlusal surface.

[0040] It should be noted that, in this application, the objective function for occlusal surface optimization is a scalar function used to mathematically quantify and balance the three optimization objectives of non-centric movement function, adjacency relationship stability, and basic anatomical morphology preservation; the non-centric slip constraint term is a mathematical penalty term used to penalize geometric penetration or functional interference between the optimized occlusal surface and the opposing tooth on the non-centric slip path; the adjacency curvature matching term is a mathematical metric term used to drive the curvature of the optimized prosthesis's prosthesis surface to be close to the curvature of the line connecting the contour points of the prosthesis extracted from the adjacent teeth; the cusp geometry preservation term is a mathematical regularization term used to constrain the position of each functional cusp of the crown and the magnitude of the change in the direction vector of the cusp direction during the optimization process; the position of the occlusal surface mesh vertices is the coordinate in three-dimensional space of each vertex constituting the triangular mesh that defines the three-dimensional surface geometry of the occlusal surface; gradient iteration adjustment is a numerical optimization method used to gradually and repeatedly modify the optimization variables (here, vertex coordinates) along the direction of the fastest descent of the objective function value to find the minimum value of the function.

[0041] In specific implementation, firstly, the objective function for occlusal surface optimization is initialized. This objective function includes a non-centric slip constraint term, an adjacent curvature matching term, and a principal cusp geometry preservation term. This can be implemented as follows: a multi-objective weighted summation scalar function is constructed as the optimization objective function. This function consists of three main parts added together. The first part is the non-centric slip constraint term, calculated by sampling multiple key points along the non-centric slip path and calculating the shortest distance between the opposing tooth and the current occlusal surface at each point. If this distance is less than a preset safe clearance threshold (e.g., 0.1 mm), the square of the distance difference is accumulated as a penalty value. The second part is the adjacent curvature matching term... The curvature matching term is calculated as follows: In the expected adjacent region of the optimized occlusal surface, a spatial curve identical to the one described in the previous step is extracted. The average curvature and Gaussian curvature of this curve are calculated, and the sum of the squares of the differences between these curves and the reference curvature values ​​obtained from adjacent teeth is calculated. The third part is the cusp geometry preservation term, which is calculated as follows: The squares of the distances between the optimized cusp apex positions and their initial positions, and the squares of the angles (or the difference in cosine similarity) between the optimized cusp ridge direction vectors and their initial direction vectors are calculated, and these values ​​are weighted and summed. The three parts are multiplied by pre-set weighting coefficients and then summed to form a complete optimizable scalar function, which will then be used to construct... The constructed weighted summation scalar function is used as the objective function for optimizing the occlusal surface. Then, starting from the initial occlusal surface, the positions of the vertices of the occlusal surface mesh are iteratively adjusted using gradients to minimize the objective function. The resulting 3D model of the occlusal surface can be implemented as follows: the 3D coordinates of all the vertices of the triangular mesh of the initial occlusal surface are used as the set of variables to be optimized. The optimization process begins with a set initial step size. In each iteration, the partial derivatives of the objective function with respect to each vertex in the X, Y, and Z coordinate directions are calculated at the current vertex coordinates. These partial derivatives together constitute the gradient vector of the objective function at the current point, and the gradient direction indicates the direction of the function. The direction of the fastest increase in the objective function value is determined; all vertex coordinates are simultaneously moved along the negative gradient direction (i.e., the direction of the fastest decrease in the function value) by a small distance determined by the current step size, thus obtaining a new set of vertex coordinates and updating the occlusal surface shape. After each coordinate update, the objective function value is recalculated. If the function value decreases, the step size is maintained or slightly increased for the next iteration; if the function value increases, the step size is decreased and the movement is retried. The above steps are repeated until a preset termination condition is met, such as the change in the objective function value being less than a minimum threshold, or the maximum number of iterations is reached. The occlusal surface mesh model that finally converges after gradient iteration adjustment is taken as the occlusal surface 3D model.

[0042] In step 104, texture compensation is performed on the occlusal surface three-dimensional model based on the material compensation coefficient of the oral prosthesis to output a complete three-dimensional prosthesis model.

[0043] In some embodiments, texture compensation is performed on the occlusal surface 3D model based on the material compensation coefficient of the dental prosthesis to output a complete 3D prosthesis model, which can be achieved by the following steps: Based on the selected manufacturing process and materials for the prosthesis, obtain the material compensation coefficient for the dental prosthesis; Along the normal direction of the outer surface of the occlusal surface three-dimensional model, the texture isometry scaling and local offset compensation are performed on the occlusal surface three-dimensional model according to the material compensation coefficient to obtain a complete three-dimensional restoration model.

[0044] It should be noted that, in this application, the material compensation coefficient of the dental prosthesis is a numerical scaling factor or offset distance used to pre-compensate for systematic deviations between the final actual size and the theoretical design size of the prosthesis caused by the characteristics of specified manufacturing processes (e.g., cutting, sintering, light curing) and specified materials (e.g., zirconia, resin, metal alloys) in the digital model; the outer surface of the occlusal surface 3D model is a set of triangular mesh surfaces characterizing all external surfaces (including occlusal surfaces and axial surfaces) of the dental prosthesis exposed to the oral environment. The normal direction is used to define the spatial direction vector perpendicular to the tangent plane at any point on the surface of the 3D model. Texture isometric scaling is a spatial transformation operation used to enlarge or reduce the entire 3D model according to a uniform ratio. Local offset compensation is a geometric operation used to translate the surface of the 3D model outward or inward by a fixed distance along its normal direction.

[0045] In practice, the material compensation coefficient for the dental prosthesis is obtained based on the selected manufacturing process and materials. This can be achieved by establishing a pre-defined process-material compensation knowledge base. This knowledge base is obtained through prior experimental calibration. For each supported manufacturing process (e.g., five-axis CNC cutting, digital light processing printing, selective laser sintering) and each supported prosthetic material (e.g., pre-sintered zirconia, dental photosensitive resin, cobalt-chromium alloy), the corresponding compensation parameters are stored. These parameters typically include a global scaling factor (used to compensate for the overall volume shrinkage rate during material sintering or curing) and a local outer surface offset distance (used to compensate for the dimensional effects caused by the cutting tool radius or printing spot radius). When the user selects a specific manufacturing process and materials for the current prosthesis design, the system automatically queries and retrieves the corresponding global scaling factor and local outer surface offset distance values ​​from this knowledge base. The global scaling factor and local outer surface offset distance obtained from the query are used as the material compensation factor for the dental restoration. Then, along the normal direction of the outer surface in the occlusal surface 3D model, the occlusal surface 3D model is subjected to texture isometric scaling and local offset compensation according to the material compensation factor to obtain a complete 3D restoration model. This can be achieved in the following way: the occlusal surface 3D model is topologically expanded, and a Boolean union operation is performed between it and the initial inner crown model to obtain a closed 3D restoration model containing a complete outer and inner surface. Compensation operations are performed on this complete model: First, the entire model is uniformly scaled in 3D using the geometric center of the model as the scaling center and the global scaling factor obtained from the material compensation factor is applied. Second, on the scaled model, the unit normal vector of each triangular facet vertex on its outer surface is calculated. Each outer surface vertex is moved outward along its own unit normal vector direction by a local outer surface offset distance obtained from the material compensation factor. This offset operation is not performed on the vertices of the inner surface (tissue surface) to ensure that the placement space between the restoration and the prepared body is not affected. After these two compensation steps, a new 3D mesh model with pre-corrected dimensions for manufacturing process and material properties is generated. The new 3D mesh model generated after completing texture isometric scaling and local offset compensation is used as the complete 3D repair body model.

[0046] In another aspect, in some embodiments, this application provides a three-dimensional modeling system for dental prostheses, with reference to... Figure 3 The figure is a schematic diagram of the structure of a three-dimensional modeling system for dental prostheses according to some embodiments of this application. The three-dimensional modeling system for dental prostheses includes: an acquisition module 201, a processing module 202, and an execution module 203, which are described below: The acquisition module 201 in this application is mainly used to acquire the target preparation body and the digital model of the opposing tooth in the oral cavity, and to perform edge line fitting on the digital model to obtain the preparation body boundary of the oral prosthesis. Processing module 202, in this application, is used to construct an initial inner coronal surface of the tooth crown through the geometric topology of the boundary of the prepared body and the direction of the path of placement of the target prepared body, determine the occlusal surface morphology of the opposing tooth crown according to the initial inner coronal surface of the tooth crown and the preset occlusal space rules, and then obtain the cusp geometric features of the occlusal surface morphology of the tooth crown. It should be noted that the processing module 202 is also used to acquire dynamic occlusal data of the opposing teeth and the morphology of adjacent teeth, and then extract the non-centric sliding component of the mandibular movement trajectory in the dynamic occlusal data of the opposing teeth and the curvature of the line connecting the contour points of the adjacent area in the morphology of the adjacent teeth. Based on the non-centric sliding component, the curvature of the line connecting the contour points of the adjacent area and the geometric features of the principal cusp, the functional occlusal surface of the oral prosthesis is morphologically constrained to obtain a three-dimensional model of the occlusal surface. The execution module 203 in this application is mainly used to perform texture compensation on the three-dimensional model of the occlusal surface based on the material compensation coefficient of the oral prosthesis, and output a complete three-dimensional prosthesis model.

[0047] The foregoing has detailed examples of the three-dimensional modeling system and method for dental prostheses provided in the embodiments of this application. It is understood that the corresponding apparatus, in order to achieve the above functions, includes hardware structures and / or software modules corresponding to the execution of each function. Those skilled in the art should readily recognize that, based on the units and algorithm steps of the examples described in conjunction with the embodiments disclosed herein, this application can be implemented in hardware or a combination of hardware and computer software. Whether a function is executed by hardware or by computer software driving hardware depends on the specified application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specified application, but such implementation should not be considered beyond the scope of this application.

[0048] In some embodiments, this application also provides a computer device, the computer device including a memory and a processor, the memory for storing a computer program, and the processor for calling and running the computer program from the memory, so that the computer device performs the above-described three-dimensional modeling method for dental prostheses.

[0049] In some embodiments, reference Figure 4 The dashed lines in the figure indicate that the unit or module is optional. This figure is a schematic diagram of the structure of a computer device for implementing a three-dimensional modeling method for dental prostheses according to an embodiment of this application. The three-dimensional modeling method for dental prostheses described in the above embodiments can be achieved through… Figure 4The computer device shown is used to implement this, and the computer device includes at least one processor 301, a memory 302 and at least one communication unit 305. The computer device may be a terminal device, a server or a chip.

[0050] Processor 301 can be a general-purpose processor or a special-purpose processor. For example, processor 301 can be a central processing unit (CPU), which can be used to control computer devices, execute software programs, and process data from software programs. The computer device may also include a communication unit 305 for inputting (receiving) and outputting (transmitting) signals.

[0051] For example, the computer device may be a chip, and the communication unit 305 may be the input and / or output circuit of the chip, or the communication unit 305 may be the communication interface of the chip, which may be a component of a terminal device, network device or other device.

[0052] For example, the computer device may be a terminal device or a server, and the communication unit 305 may be a transceiver of the terminal device or the server, or the communication unit 305 may be a transceiver circuit of the terminal device or the server.

[0053] The computer device may include one or more memories 302 storing a program 304. The program 304 can be executed by a processor 301 to generate instructions 303, causing the processor 301 to execute the method described in the above method embodiments according to the instructions 303. Optionally, the memory 302 may also store data (such as a target audit model). Optionally, the processor 301 may also read data stored in the memory 302, which may be stored at the same storage address as the program 304, or it may be stored at a different storage address than the program 304.

[0054] The processor 301 and memory 302 can be configured separately or integrated together, for example, integrated on the system on chip (SOC) of the terminal device.

[0055] It should be understood that each step of the above method embodiment can be completed by hardware logic circuits or software instructions in the processor 301. The processor 301 can be a CPU, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, such as discrete gates, transistor logic devices, or discrete hardware components.

[0056] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0057] For example, in some embodiments, this application also provides a computer-readable storage medium storing instructions or code that, when executed on a computer, cause the computer to implement the above-described three-dimensional modeling method for dental prostheses.

[0058] Although preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

[0059] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A method for three-dimensional modeling of dental prostheses, characterized in that, Includes the following steps: A digital model of the target preparation body and the opposing tooth in the oral cavity is obtained, and the edge line of the digital model is fitted to obtain the preparation body boundary of the oral prosthesis. The initial inner coronal surface of the tooth crown is constructed by the geometric topology of the boundary of the prepared body and the direction of the path of placement of the target prepared body. The occlusal surface morphology of the opposing tooth crown is determined according to the initial inner coronal surface of the tooth crown and the preset occlusal space rules, thereby obtaining the cusp geometric features of the occlusal surface morphology of the tooth crown. The dynamic occlusal data of the opposing teeth and the morphology of adjacent teeth are obtained. Then, the non-centric sliding component of the mandibular movement trajectory in the dynamic occlusal data of the opposing teeth and the curvature of the line connecting the contour points of the adjacent area in the morphology of the adjacent teeth are extracted. Based on the non-centric sliding component, the curvature of the line connecting the contour points of the adjacent area and the geometric features of the principal cusp, the morphological constraints of the functional occlusal surface of the oral prosthesis are applied to obtain a three-dimensional model of the occlusal surface. Texture compensation is performed on the occlusal surface 3D model based on the material compensation coefficient of the dental prosthesis to output a complete 3D prosthesis model.

2. The method as described in claim 1, characterized in that, By fitting the edge lines of the digital model, the prepared body boundary of the oral prosthesis is obtained, specifically including: The digital model is segmented by region growth to separate the surface of the prepared body from the surface of the gingival tissue, and the segmentation boundary is used as the initial set of edge points. The normal vector and curvature of each edge point in the initial edge point set are calculated, and outliers caused by scanning noise are filtered out to obtain the preparatory body boundary of the oral prosthesis.

3. The method as described in claim 1, characterized in that, Constructing the initial inner coronal surface of the crown using the geometric topology of the prepared body boundary and the placement path direction of the target prepared body specifically includes: Based on the geometric topology of the prepared body boundary, the region enclosed by the prepared body boundary line is identified as the inner coronal surface base. The base surface of the inner crown substrate is offset at equal intervals by means of the placement path of the target preparation body to obtain the initial inner crown surface.

4. The method as described in claim 1, characterized in that, The occlusal surface morphology of the opposing tooth crown is determined based on the initial inner coronal surface and the preset occlusal space rules, and the specific cusp geometric features of the occlusal surface morphology include: Based on the digital model of the opposing tooth, a misalignment envelope space representing the range of motion of the opposing tooth at the maximum cusp intersection position is constructed outside the inner coronal surface of the initial crown. An initial occlusal surface is generated within the misaligned envelope space, which is connected to the inner crown surface and does not penetrate the opposing tooth; The apex of the functional cusp is identified and located in the initial occlusal surface, and the three-dimensional coordinates of each functional cusp apex and the direction vector of the principal cusp ridge at the connection with the inner coronal surface are extracted to obtain the principal cusp geometric features of the occlusal surface morphology of the crown.

5. The method as described in claim 1, characterized in that, Extracting the non-centric slip component of the mandibular motion trajectory from the dynamic occlusion data of the opposing teeth and the curvature of the line connecting the contour points of the adjacent tooth morphology specifically includes: The mandibular motion trajectory in the dynamic occlusion data of opposing teeth is decomposed into a centric closure path and a non-centric glide path. The projection vector and distance of the non-centric glide path on each motion plane are calculated as the non-centric glide component. On the digital model of the adjacent tooth, the contact area adjacent to the target restoration is determined, and multiple contour points along the gingival direction within the contact area are extracted; Curve fitting is performed on all contour points, and the average curvature and Gaussian curvature of the fitted curve in three-dimensional space are calculated as the curvature of the line connecting adjacent contour points.

6. The method as described in claim 1, characterized in that, Based on the non-centric slip component, the curvature of the line connecting the contour points of the adjacent area, and the geometric features of the principal cusp, the functional occlusal surface of the oral prosthesis is morphologically constrained to obtain a three-dimensional model of the occlusal surface, which specifically includes: Initialize the objective function for occlusal surface optimization, which includes a non-central slip constraint term, an adjacent curvature matching term, and a primary cusp geometry preservation term; Starting from the initial occlusal surface, the positions of the vertices of the occlusal surface mesh are adjusted iteratively by gradient to minimize the objective function, thereby obtaining the three-dimensional model of the occlusal surface.

7. The method as described in claim 1, characterized in that, Based on the material compensation coefficient of the dental prosthesis, texture compensation is performed on the occlusal surface 3D model to output a complete 3D prosthesis model, specifically including: Based on the selected manufacturing process and materials for the prosthesis, obtain the material compensation coefficient for the dental prosthesis; Along the normal direction of the outer surface of the occlusal surface three-dimensional model, the texture isometry scaling and local offset compensation are performed on the occlusal surface three-dimensional model according to the material compensation coefficient to obtain a complete three-dimensional restoration model.

8. A three-dimensional modeling system for dental prostheses, characterized in that, include: The acquisition module is used to acquire digital models of the target preparation body and the opposing tooth in the oral cavity, and to perform edge line fitting on the digital model to obtain the preparation body boundary of the oral prosthesis. The processing module is used to construct an initial inner coronal surface of the tooth crown through the geometric topology of the boundary of the prepared body and the direction of the path of placement of the target prepared body, determine the occlusal surface morphology of the opposing tooth crown according to the initial inner coronal surface of the tooth crown and the preset occlusal space rules, and then obtain the cusp geometric features of the occlusal surface morphology of the tooth crown. The processing module is also used to acquire dynamic occlusal data of opposing teeth and morphology of adjacent teeth, and then extract the non-centric sliding component of the mandibular movement trajectory in the dynamic occlusal data of opposing teeth and the curvature of the line connecting the contour points of the adjacent area in the morphology of adjacent teeth. Based on the non-centric sliding component, the curvature of the line connecting the contour points of the adjacent area and the geometric features of the principal cusp, the functional occlusal surface of the oral prosthesis is morphologically constrained to obtain a three-dimensional model of the occlusal surface. The execution module is used to perform texture compensation on the occlusal surface 3D model based on the material compensation coefficient of the oral prosthesis, and output a complete 3D prosthesis model.

9. A computer device, characterized in that, The computer device includes a memory and a processor, the memory being used to store computer programs, and the processor being used to call and run the computer programs from the memory, causing the computer device to perform the three-dimensional modeling method for oral prostheses according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores instructions or code that, when executed on a computer, cause the computer to perform the three-dimensional modeling method for oral prostheses as described in any one of claims 1 to 7.

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