Cutting path adjustment method, cutting line generation method, cutting line adjustment method, edge line generation method, orthodontic appliance cutting line determination method, dental instrument, orthodontic appliance and manufacturing method therefor

Abstract

The present application provides a cutting path adjustment method, a cutting line generation method, a cutting line adjustment method, an edge line generation method, an orthodontic appliance cutting line determination method, a dental instrument, an orthodontic appliance and a manufacturing method therefor. The cutting path adjustment method comprises: receiving an adjustment instruction for a first cutting path, the first cutting path being a cutting path corresponding to a dental model at the i-th orthodontic step; adjusting the first cutting path on the basis of the adjustment instruction; and correspondingly adjusting second cutting paths of dental models at n orthodontic steps on the basis of an adjustment range and an adjustment magnitude of the first cutting path, wherein n is a positive integer greater than or equal to 1.

Description

Cutting path adjustment, cutting line generation, cutting line adjustment, edge line generation, methods for determining the cutting line of orthodontic appliances, dental instruments, orthodontic appliances and their manufacturing methods.

[0001] Cross-references to related applications

[0002] This application claims priority to Chinese Patent Application No. 202510377610.1, filed on March 27, 2025, entitled "A Method and Apparatus for Adjusting a Cutting Path," the entire contents of which are incorporated herein by reference; this application claims priority to Chinese Patent Application No. 202510603308.3, filed on May 9, 2025, entitled "A Method, Apparatus, Computing Device, and Storage Medium for Generating a Cutting Line," the entire contents of which are incorporated herein by reference; this application claims priority to Chinese Patent Application No. 202510625345.4, filed on May 14, 2025, entitled "A Method, Apparatus, Computing Device, and Storage Medium for Generating a Cutting Line." This application claims priority to Chinese Patent Application No. 202510857694.9, filed on June 24, 2025, entitled "Dental Instruments and Cutting Line Adjustment Method, Apparatus, Device and Medium", the entire contents of which are incorporated herein by reference; and Chinese Patent Application No. 202610187503.7, filed on February 9, 2026, entitled "Edge Line Generation Method, Orthodontic Appliance Manufacturing Method, Device and Medium", the entire contents of which are incorporated herein by reference. Technical Field

[0003] This application relates to the field of orthodontics, and more particularly to a method for adjusting the cutting path, generating the cutting line, adjusting the cutting line, generating the edge line, determining the cutting line of an orthodontic appliance, dental instruments, orthodontic appliances, and methods for manufacturing the same. Background Technology

[0004] Panoramic radiographs are an important diagnostic technique in modern dental examinations. Through a single imaging session, they can conveniently and quickly show the cutting path of orthodontic appliances—the specific trajectory along which the appliance material is cut during appliance fabrication. When fabricating appliances, the patient's dental model data is first imported into computer software to analyze tooth alignment, occlusion, and other factors to determine the treatment goals and tooth movement plans for each orthodontic step. This information is then used to plan the shape and cutting path of the appliance.

[0005] Because individual patients' dental models vary, operators usually make minor adjustments to the cutting path to better match the actual condition of the patient's teeth. However, currently, when operators adjust the cutting path of a certain orthodontic step, they only change the cutting path of that step. For other orthodontic steps related to that step, operators need to manually adjust their cutting paths one by one. This adjustment method lacks flexibility and is inefficient. Summary of the Invention

[0006] This application provides a method for adjusting the cutting path, generating the cutting line, adjusting the cutting line, generating the edge line, determining the cutting line of the orthodontic appliance, a dental instrument, an orthodontic appliance, and a method for manufacturing the same, for dynamically adjusting the cutting path of multiple related orthodontic steps.

[0007] In a first aspect, this application provides a method for adjusting a cutting path, the method comprising: receiving an adjustment instruction for a first cutting path; the first cutting path being a cutting path corresponding to the dentition model of the i-th orthodontic step; adjusting the first cutting path according to the adjustment instruction; and adjusting a second cutting path of the dentition model of n orthodontic steps accordingly based on the adjustment range and adjustment magnitude of the first cutting path; where n is a positive integer greater than or equal to 1.

[0008] In the above technical solution, based on the adjustment range and adjustment magnitude of the cutting path corresponding to the dentition model of the i-th orthodontic step, the second cutting path of the dentition model of the n-th orthodontic step is also adjusted accordingly. This solves the problem that the adjustment of the cutting path is inflexible and it is difficult to adjust multiple orthodontic steps in a follow-up manner during the fabrication of the orthodontic appliance. It can achieve more efficient and accurate cutting path adjustment and improve the fabrication accuracy of the orthodontic appliance.

[0009] In one possible design, before adjusting the second cutting path of the dental model for the n orthodontic steps, the method further includes: determining the n orthodontic steps that follow the i-th orthodontic step based on the similarity between the first cutting path of the i-th orthodontic step and the second cutting paths of the other orthodontic steps.

[0010] In the above technical solution, n correction steps that follow the i-th correction step are determined based on the similarity of the cutting path. Then, the n correction steps that have high similarity to the i-th correction step in terms of cutting path features are adjusted accordingly, making the adjustment of the cutting path more targeted and accurate.

[0011] In one possible design, based on the similarity between the first cutting path of the i-th correction step and the second cutting paths of the other correction steps, n correction steps that follow the i-th correction step are determined, including: determining a first sub-cutting path within the adjustment range indicated by the adjustment instruction from the first cutting path; for each other correction step, determining a second sub-cutting path with the same adjustment range from the second cutting paths of the other correction steps; calculating the similarity between the first sub-cutting path and the second sub-cutting path; and selecting the n correction steps with a similarity greater than a set threshold as the n correction steps that follow the i-th correction step.

[0012] In the above technical solution, a first sub-cutting path within the adjustment range is determined from the first cutting path, and a second sub-cutting path within the corresponding range is found in the second cutting paths of other correction steps. The similarity between the two is then calculated, and correction steps with a similarity greater than a set threshold are taken as follow-up correction steps. This method makes the process of determining follow-up correction steps more precise and quantifiable, and can more accurately screen correction steps with similar cutting path characteristics to the i-th correction step, thereby ensuring the effectiveness and accuracy of subsequent adjustments to the cutting paths of these correction steps.

[0013] In one possible design, determining a second sub-cutting path with the same adjustment range from the second cutting paths of other orthodontic steps includes: obtaining the position information of each first control point in the first sub-cutting path on the dental model; determining each second control point in the second cutting paths of other orthodontic steps that has the same position information as the first control point; and using the path formed by the second control points as the second sub-cutting path.

[0014] In the above technical solution, by obtaining the position information of each first control point within the first sub-cutting path on the dental model, second control points with the same position information are determined in the second cutting paths of other orthodontic steps, thus forming a second sub-cutting path. This method ensures that the second sub-cutting path corresponding to the first sub-cutting path can be accurately found in the cutting paths of different orthodontic steps, providing a basis for subsequent accurate similarity calculation and reasonable adjustment of the cutting path, and improving the accuracy and consistency of cutting path adjustment.

[0015] In one possible design, the position information of each control point on the cutting path on the dental model is established as follows: For each control point on the cutting path, the tooth or gingiva closest to the control point is determined; if the closest control point is a tooth, the position information of the control point is set as the tooth's sequence number; if the closest control point is a gingiva, the position information of the control point is determined based on the position information of the third control point before the control point and the position information of the fourth control point after the control point; the third control point is the first control point before the control point whose position information is the tooth's sequence number, and the fourth control point is the first control point after the control point whose position information is the tooth's sequence number.

[0016] The above technical solution establishes the position information of each control point on the cutting path on the dental model. This method can accurately locate each control point on the cutting path on the dental model, providing an important foundation for achieving precise matching and adjustment between sub-cutting paths of different orthodontic steps, and helping to improve the accuracy and reliability of the entire cutting path adjustment method.

[0017] In one possible design, receiving an adjustment instruction for a first cutting path includes: receiving a single-point adjustment instruction for a fifth control point on the first cutting path; the single-point adjustment instruction is triggered by a first operation targeting the fifth control point; adjusting the first cutting path according to the adjustment instruction includes: performing a single-point adjustment on the fifth control point according to the single-point adjustment instruction; and adjusting a second cutting path of a dental model with n orthodontic steps based on the adjustment range and adjustment magnitude of the first cutting path, including: adjusting a sixth control point of the dental model with n orthodontic steps based on the adjustment magnitude of the fifth control point; the sixth control point is a control point in the n orthodontic steps corresponding to the fifth control point.

[0018] In the above technical solution, a single-point adjustment instruction is received for the fifth control point on the first cutting path and the single-point adjustment is performed. At the same time, based on this, the sixth control point of the dental model of n orthodontic steps is adjusted accordingly. This method makes the single-point adjustment operation coherent and consistent among multiple orthodontic steps, and can quickly and accurately adjust the control points corresponding to the cutting paths of multiple related orthodontic steps.

[0019] In one possible design, based on the adjustment range of the fifth control point, the sixth control point of the dental model for n orthodontic steps is adjusted accordingly, including: determining the index of the triangular facet on the three-dimensional mesh where the fifth control point is located after adjustment; the three-dimensional mesh is a three-dimensional mesh representing teeth or a three-dimensional mesh representing gingiva; calculating the first position of the fifth control point on the triangular facet after adjustment; for each orthodontic step, adjusting the position of the sixth control point to the first position on the triangular facet corresponding to the index.

[0020] In the above technical solution, by determining the index of the triangular facet on the three-dimensional mesh where the fifth control point of the i-th correction step is located after adjustment and the position on the triangular facet, the sixth control points of n correction steps are adjusted to the same position on the triangular facet with the same index. This method makes the adjustment of control points in three-dimensional space more precise and operable, and ensures the consistency and accuracy of single-point adjustment between different correction steps.

[0021] In one possible design, receiving an adjustment instruction for a first cutting path includes: receiving a segment adjustment instruction for the first cutting path; the segment adjustment instruction is triggered by a second operation; adjusting the first cutting path according to the adjustment instruction includes: adjusting a third sub-cutting path of a corresponding segment of the first cutting path according to the segment adjustment instruction; and adjusting a second cutting path of a dental model for n orthodontic steps based on the adjustment range and adjustment magnitude of the first cutting path, including: adjusting the second sub-cutting path of the dental model for n orthodontic steps by a corresponding adjustment magnitude based on the adjustment magnitude of the third sub-cutting path within the adjustment range of the first cutting path; the second sub-cutting path is a sub-cutting path in the n orthodontic steps with the same adjustment range as the first cutting path.

[0022] The above technical solution enables the follow-up adjustment of the cutting path segment by n correction steps. It receives a segment adjustment instruction for the first cutting path and adjusts the third sub-cutting path of the corresponding segment. Simultaneously, based on this, it adjusts the second sub-cutting path with the same adjustment range among the n correction steps accordingly. This method allows the adjustment of the cutting path segment to be effectively transmitted and applied among multiple related correction steps, facilitating the overall optimization and coordination of the cutting paths across multiple correction steps.

[0023] Secondly, embodiments of this application provide a cutting path adjustment device, the device comprising:

[0024] A receiving module is used to receive adjustment instructions for the first cutting path; the first cutting path is the cutting path corresponding to the dental model of the i-th orthodontic step.

[0025] An execution module is used to adjust the first cutting path according to the adjustment instruction;

[0026] The execution module is further configured to adjust the second cutting path of the dental model with n orthodontic steps according to the adjustment range and adjustment magnitude of the first cutting path; n is a positive integer greater than or equal to 1.

[0027] In one possible design, the device further includes a processing module, which, before adjusting the second cutting paths of the dental model for the n orthodontic steps, determines the n orthodontic steps that follow the i-th orthodontic step based on the similarity between the first cutting path of the i-th orthodontic step and the second cutting paths of the other orthodontic steps.

[0028] In one possible design, when the processing module determines the n correction steps that follow the i-th correction step based on the similarity between the first cutting path of the i-th correction step and the second cutting paths of the other correction steps, it specifically performs the following: determining a first sub-cutting path within the adjustment range indicated by the adjustment instruction from the first cutting path; determining a second sub-cutting path with the same adjustment range from the second cutting paths of the other correction steps for each other correction step; calculating the similarity between the first sub-cutting path and the second sub-cutting path; and selecting the n correction steps with a similarity greater than a set threshold as the n correction steps that follow the i-th correction step.

[0029] In one possible design, when the processing module determines a second sub-cutting path with the same adjustment range from the second cutting paths of other orthodontic steps, it is specifically used to obtain the position information of each first control point in the first sub-cutting path on the dental model; determine each second control point in the second cutting path of other orthodontic steps that has the same position information as the first control point; and take the path formed by each second control point as the second sub-cutting path.

[0030] In one possible design, the processing module is further configured to establish the position information of each control point on the cutting path on the dental model in the following manner: for each control point on the cutting path, determine the tooth or gingiva closest to the control point; if the closest control point is a tooth, then set the position information of the control point as the tooth's sequence number; if the closest control point is a gingiva, then determine the position information of the control point based on the position information of the third control point before the control point and the position information of the fourth control point after the control point; the third control point is the first control point before the control point whose position information is the tooth's sequence number, and the fourth control point is the first control point after the control point whose position information is the tooth's sequence number.

[0031] In one possible design, the receiving module, when receiving an adjustment instruction for the first cutting path, is specifically configured to receive a single-point adjustment instruction for a fifth control point on the first cutting path; the single-point adjustment instruction is triggered by a first operation targeting the fifth control point; the execution module, when adjusting the first cutting path according to the adjustment instruction, is specifically configured to perform a single-point adjustment on the fifth control point according to the single-point adjustment instruction; the execution module, when adjusting the second cutting path of the dental model with n orthodontic steps based on the adjustment range and adjustment magnitude of the first cutting path, is specifically configured to perform a corresponding adjustment on the sixth control point of the dental model with n orthodontic steps based on the adjustment magnitude of the fifth control point; the sixth control point is the control point corresponding to the fifth control point in the n orthodontic steps.

[0032] In one possible design, when the execution module adjusts the sixth control point of the dental model for n orthodontic steps based on the adjustment range of the fifth control point, it is specifically used to determine the index of the triangular facet on the three-dimensional mesh where the fifth control point is located after adjustment; the three-dimensional mesh is a three-dimensional mesh representing teeth or a three-dimensional mesh representing gingiva; calculate the first position of the fifth control point on the triangular facet after adjustment; and for each orthodontic step, adjust the position of the sixth control point to the first position on the triangular facet corresponding to the index.

[0033] In one possible design, when the receiving module receives an adjustment instruction for the first cutting path, it is specifically used to receive a segment adjustment instruction for the first cutting path; the segment adjustment instruction is triggered by a second operation; when the execution module adjusts the first cutting path according to the adjustment instruction, it is specifically used to adjust the third sub-cutting path of the corresponding segment of the first cutting path according to the segment adjustment instruction; when the execution module adjusts the second cutting path of the dental model for n orthodontic steps according to the adjustment range and adjustment magnitude of the first cutting path, it is specifically used to adjust the second sub-cutting path of the dental model for n orthodontic steps according to the adjustment magnitude of the third sub-cutting path within the adjustment range of the first cutting path; the second sub-cutting path is a sub-cutting path in the n orthodontic steps with the same adjustment range as the first cutting path.

[0034] Thirdly, embodiments of this application provide a method for generating cutting lines. This method can be executed by a cutting line generating device, which can be a terminal device or a module for a terminal device, or a server or a module for a server. This application does not limit the subject executing the method. The method includes: obtaining initial cutting lines for the entire tooth and gingiva in a digital dental model; determining, from the initial cutting lines, a first region sub-line located in a virtual tooth region in the digital dental model and a second region sub-line located in a real tooth region adjacent to the virtual tooth; and adjusting the first region sub-line based on the second region sub-line to obtain updated cutting lines.

[0035] The above solution, on the one hand, can automatically determine the cutting line of the virtual tooth without the need for manual drawing or adjustment of the initial cutting line corresponding to the virtual tooth, thus improving the efficiency of determining the cutting line of the virtual tooth region; on the other hand, since virtual teeth often have similar features to their adjacent real teeth, adjusting the first sub-line using the second sub-line of the adjacent real tooth region can accurately and effectively determine the cutting line of the virtual tooth region.

[0036] In one possible implementation, the real teeth adjacent to the virtual tooth are the nearest real teeth on both sides of the virtual tooth, or the real teeth adjacent to the virtual tooth are the real teeth on one side of the virtual tooth.

[0037] In the above scheme, the real teeth adjacent to the virtual teeth can be the nearest real teeth on both sides or the real teeth on one side. By utilizing the relationship between the virtual teeth and the adjacent real teeth, the cutting line of the virtual teeth can be accurately and effectively determined.

[0038] In one possible implementation, a relative low point in the second region sub-line is determined; wherein, points closer to the gingiva in the region sub-line are lower; an edge point and a midpoint in the first region sub-line are determined; wherein, the coordinate value of the midpoint in the root direction is determined based on the coordinate value of the relative low point in the root direction; a third region sub-line is generated based on the edge point and the midpoint; the third region sub-line is used to replace the first region sub-line.

[0039] In the above scheme, for a single tooth, the relative low point of the crown and gingival dividing line is often located at the center of the crown surface. Therefore, the relative low point in the second region sub-line can accurately reflect the coordinate value of the midpoint in the root direction, thereby enabling accurate and effective determination of the coordinate value of the cutting line of the virtual tooth in the root direction.

[0040] In one possible implementation, the relative low point is the lowest point in the second region sub-line.

[0041] In one possible implementation, the first and last points in the first region sub-line are determined as edge points in the first region sub-line; based on the coordinate values ​​of the first and last points on the tooth surface, the coordinate values ​​of the middle point on the tooth surface are determined.

[0042] The above scheme can accurately determine the center position of the virtual tooth based on the first and last points in the first region sub-line.

[0043] In one possible implementation, the edge points and the intermediate points are connected and the connection is smoothed; the smoothed connection is sampled according to the sampling rate of the initial cutting line to obtain each sampling point; and a third region sub-line is generated based on each sampling point.

[0044] The above scheme samples the smoothed lines according to the sampling rate of the initial cutting line, which can ensure that the sub-lines of the third region have the same sampling rate as the sub-lines of the second region.

[0045] In one possible implementation, the midpoint is determined to be located above the neck of the virtual tooth and not exceeding the virtual tooth.

[0046] The above method can accurately and effectively determine the position of the midpoint on the virtual tooth.

[0047] In one possible implementation, a bounding box for the virtual tooth is determined; an initial cutting line located within the bounding box is determined as a first region sub-line located in the virtual tooth region of the digital dental model.

[0048] The above scheme can accurately and effectively determine the sub-line of the first region.

[0049] In one possible implementation, the centroid of the crown of the virtual tooth in the digital dental model is taken as the origin, and the coordinates extend outward along the axis of the world coordinate system; three intersection points are determined based on the intersection positions of the outwardly extending world coordinate axis and the surface of the crown of the virtual tooth; and the cuboid formed by extending the three intersection points outward is determined as the bounding box of the virtual tooth.

[0050] The above solution can accurately and effectively determine the bounding box.

[0051] In one possible implementation, the region sub-line corresponding to the actual tooth located within a predetermined distance to the left of the first region sub-line in the initial cutting line is designated as the second region sub-line on the left; and the region sub-line corresponding to the actual tooth located within a predetermined distance to the right of the first region sub-line in the initial cutting line is designated as the second region sub-line on the right.

[0052] The above scheme can accurately and effectively determine the second region sub-lines on the left and right sides of the virtual tooth.

[0053] In one possible implementation, determining the relative low point in the second region sub-line includes: determining the lowest point in the left-side second region sub-line as the left-side relative low point; determining the lowest point in the right-side second region sub-line as the right-side relative low point; the coordinate value of the intermediate point in the root direction is determined based on the coordinate value of the relative low point in the root direction, including: determining the coordinate value of the intermediate point in the root direction based on the coordinate values ​​of the left-side relative low point and the right-side relative low point in the root direction.

[0054] The above scheme can accurately and effectively determine the relative low points on the left and right sides of the virtual tooth, as well as the coordinates of the midpoint in the direction of the tooth root.

[0055] One possible implementation involves displaying the updated cutting line.

[0056] The above solution can correctly display the updated cutting lines and help people understand the generation effect of virtual tooth cutting lines.

[0057] Fourthly, embodiments of this application provide a cutting line generation apparatus, comprising: an acquisition unit and a determination unit. The acquisition unit is configured to acquire initial cutting lines of the entire tooth and gingiva in a digital dental model; the determination unit is configured to determine, from the initial cutting lines, a first region sub-line located in a virtual tooth region of the digital dental model and a second region sub-line located in a real tooth region adjacent to the virtual tooth; based on the second region sub-line, the first region sub-line is adjusted to obtain an updated cutting line.

[0058] In one possible implementation, the real teeth adjacent to the virtual tooth are the nearest real teeth on both sides of the virtual tooth, or the real teeth adjacent to the virtual tooth are the real teeth on one side of the virtual tooth.

[0059] In one possible implementation, the determining unit is configured to determine a relative low point in the second region sub-line; wherein, points closer to the gingiva in the region sub-line are lower; determine an edge point and a midpoint in the first region sub-line; wherein, the coordinate value of the midpoint in the root direction is determined based on the coordinate value of the relative low point in the root direction; generate a third region sub-line based on the edge point and the midpoint; the third region sub-line is used to replace the first region sub-line.

[0060] In one possible implementation, the relative low point is the lowest point in the second region sub-line.

[0061] In one possible implementation, the determining unit is used to determine the first and last points in the first region sub-line as edge points in the first region sub-line; and to determine the coordinates of the middle point on the tooth surface based on the coordinates of the first and last points on the tooth surface.

[0062] In one possible implementation, the determining unit is used to connect the edge points and the intermediate points and smooth the connection; sample the smoothed connection according to the sampling rate of the initial cutting line to obtain each sampling point; and generate a third region sub-line based on each sampling point.

[0063] In one possible implementation, the determining unit is configured to determine that the intermediate point is located above the neck of the virtual tooth and does not exceed the virtual tooth.

[0064] In one possible implementation, the determining unit is used to determine the bounding box of the virtual tooth; and to determine the initial cutting line located within the bounding box as the first region sub-line located in the virtual tooth region of the digital dental model.

[0065] In one possible implementation, the determining unit is used to extend outward along the axis of the world coordinate system with the centroid of the crown of the virtual tooth in the digital dental model as the origin; to determine three intersection points based on the intersection positions of the outwardly extending world coordinate axis and the surface of the crown of the virtual tooth; and to determine the cuboid formed by extending the three intersection points outward as the bounding box of the virtual tooth.

[0066] In one possible implementation, the determining unit is configured to designate the region sub-line corresponding to the actual tooth located within a predetermined distance to the left of the first region sub-line in the initial cutting line as the second region sub-line on the left; and designate the region sub-line corresponding to the actual tooth located within a predetermined distance to the right of the first region sub-line in the initial cutting line as the second region sub-line on the right.

[0067] In one possible implementation, the determining unit is used to determine the lowest point in the second sub-line of the left side as the relative low point of the left side; determine the lowest point in the second sub-line of the right side as the relative low point of the right side; and determine the coordinate value of the intermediate point in the root direction based on the coordinate values ​​of the relative low point of the left side and the relative low point of the right side in the root direction.

[0068] In one possible implementation, the above-mentioned device further includes a display unit for displaying the updated cutting line.

[0069] Fifthly, embodiments of the present invention provide a method for determining the cutting line of an orthodontic appliance, comprising: determining an initial cutting line using a dental model; the initial cutting line being used to characterize the boundary between the crown and the gingiva; obtaining the cutting line of the orthodontic appliance based on adjustment information of the initial cutting line; the adjustment information being used to indicate the adjustment range of the initial cutting line toward the gingiva; and the cutting line of the orthodontic appliance being located in the gingival protrusion area within the adjustment range.

[0070] In the above technical solution, the orthodontic appliance cutting line is obtained by adjusting the initial cutting line, so that the appliance cutting line has a higher degree of wrapping around the gingival area than the initial cutting line. This improves the wearing comfort of the user when wearing the orthodontic appliance generated by the appliance cutting line.

[0071] Optionally, the appliance cutting line is the cutting line formed by each protruding point in the gingival region within the adjustment range.

[0072] Optionally, at least one cutting point in the orthodontic appliance cutting line is determined by distance and curvature, where the distance is the distance between the cutting point and the initial point corresponding to the initial cutting line, and the curvature is the degree of curvature of the gingival region where the cutting point is located.

[0073] In the above technical solution, both distance and curvature are taken into account during the process of generating the orthodontic appliance cutting line, so that the subsequent orthodontic appliance cutting line generated can achieve both strong wrapping and avoid compressing the gums.

[0074] Optionally, curvature is weighted higher than distance.

[0075] Optionally, based on the adjustment information of the initial cutting line, the orthodontic appliance cutting line is obtained through the initial cutting line, including: based on the distance adjustment range indicated by the adjustment information of the initial cutting line, multiple adjustment cutting lines are obtained by moving the initial cutting line toward the gingiva by a set step size; and the adjustment cutting line that meets the requirements of the gingival protrusion area is used as the orthodontic appliance cutting line.

[0076] In the above technical solution, by finding an adjustment appliance within the distance adjustment range that meets the requirements of the gingival protrusion area as the appliance cutting line, both the distance requirement and the gingival protrusion requirement are taken into account, so that the braces generated by the appliance cutting line can achieve both strong coverage and avoid compressing the gums.

[0077] Optionally, based on the adjustment information of the initial cutting line, the orthodontic appliance cutting line is obtained from the initial cutting line, including: determining multiple candidate points on the dental model for any initial point in the initial cutting line based on the distance adjustment range indicated by the adjustment information of the initial cutting line; selecting the cutting point corresponding to the initial point from the multiple candidate points according to the distance between each candidate point and the initial point, and the curvature of the gingival region where each candidate point is located; and generating the orthodontic appliance cutting line according to the cutting points corresponding to each initial point of the initial cutting line.

[0078] In the above technical solution, by finding an adjustment appliance that meets the curvature requirements within the distance adjustment range as the appliance cutting line, both distance requirements and curvature requirements are considered in the process of generating the appliance cutting line. This ensures that the braces generated by the appliance cutting line can achieve both strong coverage and avoid compressing the gums.

[0079] Optionally, based on the distance adjustment range indicated by the adjustment information of the initial cutting line, multiple candidate points on the dental model are determined for any initial point in the initial cutting line, including: for at least one initial point in the initial cutting line, based on the distance adjustment range indicated by the adjustment information of the initial cutting line, sampling is performed on the dental model along the normal direction towards the gingiva from the initial point within the distance adjustment range to obtain multiple candidate points of the initial point on the dental model.

[0080] Optionally, the adjustment range includes a distance adjustment range for the anterior teeth region and a distance adjustment range for the posterior teeth region; wherein the distance adjustment range for the anterior teeth region is greater than the distance adjustment range for the posterior teeth region.

[0081] Optionally, the initial cutting line is determined using a dental model, including: determining the contour information between each crown and the gingiva using the dental model; sampling each initial point based on the contour information between each crown and the gingiva; and performing curve fitting on each initial point to obtain the initial cutting line.

[0082] Optionally, the initial cutting line adjustment information is obtained by inputting it in the user interface; and / or after obtaining the orthodontic appliance cutting line, it also includes: displaying a dental model with the orthodontic appliance cutting line in the user interface.

[0083] Sixthly, an orthodontic appliance is provided in the embodiments of the present invention. The orthodontic appliance is shell-shaped and includes multiple cavities for accommodating teeth. When the orthodontic appliance is worn in the user's oral cavity, the edge line of the orthodontic appliance is located in the user's gingival protrusion area.

[0084] Optionally, the edge line of the appliance is located at each protruding point in the gingival region within the adjustment range; the adjustment range is derived from the adjustment instructions for the initial cutting line.

[0085] Optionally, the edge line of the orthodontic appliance is obtained by the orthodontic appliance cutting line obtained by the method for determining the orthodontic appliance cutting line as in the first aspect.

[0086] In a seventh aspect, an embodiment of the present invention provides an apparatus for determining an orthodontic appliance cutting line, comprising: an acquisition unit for determining an initial cutting line using a dental model; the initial cutting line characterizing the boundary between the crown and the gingiva; a processing unit for obtaining an orthodontic appliance cutting line based on adjustment information of the initial cutting line; the adjustment information indicating the adjustment range of the initial cutting line toward the gingiva; and the orthodontic appliance cutting line located in a gingival protrusion area within the adjustment range.

[0087] Eighthly, this application provides a method for adjusting cutting lines, the method comprising:

[0088] Using a digital model of the teeth, the area to be adjusted within the initial cutting line is determined;

[0089] The initial cutting line corresponding to the area to be adjusted is adjusted towards the crown direction so that the adjusted cutting line and the outermost contour line of the crown area in the digital tooth model meet the preset requirements; the preset requirements are wearing requirements or orthodontic requirements; the adjusted cutting line is used to obtain the dental instrument corresponding to the digital tooth model.

[0090] In one possible implementation, determining the area to be adjusted in the initial cutting line using a digital tooth model includes:

[0091] The initial cutting line and the outermost contour line are projected in a preset direction to obtain a first projection line and a second projection line; based on the first projection line and the second projection line, the area to be adjusted in the initial cutting line is determined.

[0092] In one possible implementation, determining the area to be adjusted in the initial cutting line based on the first projection line and the second projection line includes:

[0093] The region between the first projection line and the second projection line that satisfies at least one of the following conditions is identified as the region to be adjusted in the initial cutting line; the at least one condition includes:

[0094] The distance between the first projection line and the second projection line in any region exceeds a first threshold.

[0095] The length difference between the first projection line and the second projection line in any region exceeds the second threshold.

[0096] The area difference between the first projection line and the second projection line in any region exceeds a third threshold.

[0097] In one possible implementation, the area to be adjusted includes at least one tooth and / or the area between two adjacent teeth.

[0098] In one possible implementation, the step of projecting the initial cutting line and the outermost contour line in a preset direction to obtain a first projection line and a second projection line includes:

[0099] Projecting the tooth regions corresponding to the initial cutting line and the outermost contour line in a preset direction respectively, to obtain the first projection line and the second projection line; or,

[0100] Projecting the anterior tooth region and the two posterior tooth regions corresponding to the initial cutting line and the outermost contour line respectively in a preset direction yields the first projection line and the second projection line; or,

[0101] The entire regions of the initial cutting line and the outermost contour line are projected in a preset direction to obtain the first projection line and the second projection line.

[0102] In one possible implementation, the preset direction includes at least one of the following: the long axis direction of the tooth, the disengagement direction of the dental instrument corresponding to the tooth, the direction perpendicular to the occlusal plane, the direction perpendicular to the horizontal plane, the overall disengagement direction of the dental instrument, the direction perpendicular to the plane where the anterior tooth region is located, the overall disengagement direction of the anterior tooth region, the direction perpendicular to the planes where the two posterior tooth regions are located respectively, and the overall disengagement directions of the two posterior tooth regions respectively.

[0103] In one possible implementation, adjusting the initial cutting line corresponding to the area to be adjusted towards the crown direction, so that the adjusted cutting line and the outermost contour line of the digital tooth model in the crown region meet preset requirements, includes:

[0104] Adjust the initial cutting line corresponding to the area to be adjusted towards the crown direction until the adjusted cutting line and the outermost contour line of the digital tooth model in the crown region satisfy at least one of the following:

[0105] The distance between the first projection line and the second projection line in any region does not exceed a first threshold; and / or, the length difference between the first projection line and the second projection line in any region does not exceed a second threshold; and / or, the area difference between the first projection line and the second projection line in any region does not exceed a third threshold.

[0106] In one possible implementation, the first threshold, the second threshold, and the third threshold are all determined based on at least one of the following conditions: the material of the dental instrument in any region, the thickness of the dental instrument in any region, the position of the teeth in any region, and the developmental state of the teeth in any region.

[0107] In one possible implementation, before determining the area to be adjusted in the initial cutting line, the method further includes:

[0108] The gingival line and the outermost contour line of the crown region of each tooth in the digital tooth model are projected in a preset direction to obtain the third projection line and the fourth projection line; it is determined that the third projection line and the fourth projection line of at least one tooth meet the adjustment requirements of the initial cutting line.

[0109] Ninthly, this application also provides a dental instrument, which has a shell-like structure;

[0110] The outline of the opening of the shell-like structure and the outermost outline of the dental instrument in the crown area meet preset requirements; the preset requirements are to meet the wearing requirements or orthodontic requirements of the dental instrument; the opening of the shell-like structure is obtained by cutting lines and the corresponding digital model of the teeth of the dental instrument.

[0111] In one possible implementation, the opening contour line and the outermost contour line satisfy a preset requirement by using a first projection line of the opening contour line in a preset direction and a second projection line of the outermost contour line in a preset direction.

[0112] In one possible implementation, the preset requirement is that the distance between the first projection line and the second projection line in any region does not exceed a first threshold; and / or, the length difference between the first projection line and the second projection line in any region does not exceed a second threshold; and / or, the area difference between the first projection line and the second projection line in any region does not exceed a third threshold.

[0113] In one possible implementation, the preset direction includes at least one of the following: the long axis direction of the tooth, the disengagement direction of the dental instrument corresponding to the tooth, the direction perpendicular to the occlusal plane, the direction perpendicular to the horizontal plane, the overall disengagement direction of the dental instrument, the plane where the anterior tooth region is located, the overall disengagement direction of the anterior tooth region, the planes where the two posterior tooth regions are located respectively, and the overall disengagement directions of the two posterior tooth regions respectively.

[0114] In one possible implementation, the first threshold, the second threshold, and the third threshold are all determined based on at least one of the following conditions: the material of the dental instrument in any region, the thickness of the dental instrument in any region, the position of the teeth in any region, and the developmental state of the teeth in any region.

[0115] Tenthly, this application provides a cutting line adjustment device, the device comprising:

[0116] The determination module is used to determine the area to be adjusted in the initial cutting line using a digital model of the teeth;

[0117] An adjustment module is used to adjust the initial cutting line corresponding to the area to be adjusted towards the crown direction so that the adjusted cutting line and the outermost contour line of the crown area in the digital tooth model meet preset requirements; the preset requirements are wearing requirements or orthodontic requirements; the adjusted cutting line is used to obtain the dental instrument corresponding to the digital tooth model.

[0118] In one possible implementation, the determining module is specifically used to project the initial cutting line and the outermost contour line in a preset direction to obtain a first projection line and a second projection line; and to determine the area to be adjusted in the initial cutting line based on the first projection line and the second projection line.

[0119] In one possible implementation, the adjustment module is specifically configured to determine the region between the first projection line and the second projection line that satisfies at least one of the following conditions as the region to be adjusted in the initial cutting line; the at least one condition includes:

[0120] The distance between the first projection line and the second projection line in any region exceeds a first threshold.

[0121] The length difference between the first projection line and the second projection line in any region exceeds the second threshold.

[0122] The area difference between the first projection line and the second projection line in any region exceeds a third threshold.

[0123] In one possible implementation, the area to be adjusted includes at least one tooth and / or the area between two adjacent teeth.

[0124] In one possible implementation, the adjustment module is specifically used to project the tooth regions corresponding to the initial cutting line and the outermost contour line in a preset direction to obtain the first projection line and the second projection line; or,

[0125] Projecting the anterior tooth region and the two posterior tooth regions corresponding to the initial cutting line and the outermost contour line respectively in a preset direction yields the first projection line and the second projection line; or,

[0126] The entire regions of the initial cutting line and the outermost contour line are projected in a preset direction to obtain the first projection line and the second projection line.

[0127] In one possible implementation, the preset direction includes at least one of the following: the long axis direction of the tooth, the disengagement direction of the dental instrument corresponding to the tooth, the direction perpendicular to the occlusal plane, the direction perpendicular to the horizontal plane, the overall disengagement direction of the dental instrument, the direction perpendicular to the plane where the anterior tooth region is located, the overall disengagement direction of the anterior tooth region, the direction perpendicular to the planes where the two posterior tooth regions are located respectively, and the overall disengagement directions of the two posterior tooth regions respectively.

[0128] The adjustment module is specifically used to adjust the initial cutting line corresponding to the area to be adjusted towards the crown direction until the adjusted cutting line and the outermost contour line of the digital tooth model in the crown area satisfy at least one of the following: the distance between the first projection line and the second projection line in any area does not exceed a first threshold; and / or, the length difference between the first projection line and the second projection line in any area does not exceed a second threshold; and / or, the area difference between the first projection line and the second projection line in any area does not exceed a third threshold.

[0129] In one possible implementation, the first threshold, the second threshold, and the third threshold are all determined based on at least one of the following conditions: the material of the dental instrument in any region, the thickness of the dental instrument in any region, the position of the teeth in any region, and the developmental state of the teeth in any region.

[0130] In one possible implementation, the determining module is further configured to, before determining the area to be adjusted in the initial cutting line, project the gingival line and the outermost contour line of the crown region of each tooth in the digital tooth model in a preset direction to obtain a third projection line and a fourth projection line; and determine that the third projection line and the fourth projection line of at least one tooth meet the adjustment requirements of the initial cutting line.

[0131] Eleventhly, embodiments of this application provide an edge line generation method, the method comprising: acquiring a digital dental model of a user; determining the difficulty of removing and wearing the orthodontic appliance corresponding to the edge line of the target orthodontic appliance based on the user's tooth feature data extracted from the digital dental model; the tooth feature data being used to characterize the morphological features of the user's teeth; adjusting the edge line of the target orthodontic appliance according to the difficulty of removing and wearing the appliance to obtain a first orthodontic appliance edge line; the first orthodontic appliance edge line being used to generate the edge morphology of the target orthodontic appliance corresponding to the digital dental model, or the first orthodontic appliance edge line being the edge morphology of the target orthodontic appliance.

[0132] In the above scheme, the difficulty of removing and wearing the aligner is determined by extracting tooth feature data based on the user's digital dental model, with the user's gingival margin as the edge line of the target aligner. Then, the edge line of the target aligner is adjusted based on the determined difficulty of removing and wearing the aligner, so as to obtain a reasonable first aligner edge line. This helps to realize the personalized manufacturing of the aligner, and the target aligner with the first aligner edge line as the edge shape can be easily removed and worn by the user while maintaining sufficient wrapping force and force.

[0133] In one possible implementation, determining the difficulty of appliance insertion and removal corresponding to the edge line of the target appliance with the user's gingival margin as the target appliance includes: for the target tooth in the digital dental model, comparing the parameter values ​​corresponding to the tooth feature data of the target tooth with the threshold values ​​corresponding to the tooth feature data to determine the difficulty of appliance insertion and removal in the area where the target tooth is located; the target tooth is any tooth in the digital dental model.

[0134] In one possible implementation, the method further includes: adjusting the edge line of the target orthodontic appliance to obtain the first edge line of the orthodontic appliance based on the difficulty of removing and inserting the appliance and the edge adjustment strategy; the edge adjustment strategy includes adjusting the edge line of the orthodontic appliance towards the crown direction by an amount that is positively correlated with the difficulty of removing and inserting the appliance.

[0135] In one possible implementation, the edge adjustment strategy includes at least one of the following: the tooth's removal / adoption interval; tooth number; removal / adoption order; removal / adoption priority; and removal / adoption location.

[0136] In one possible implementation, the edge line of the target orthodontic appliance is adjusted to obtain the first edge line of the orthodontic appliance based on the difficulty of removing and wearing the appliance and the edge adjustment strategy. This includes: adjusting the part of the edge line of the target orthodontic appliance corresponding to the target tooth towards the crown direction, based on the fact that the difficulty of removing and wearing the appliance in the area where the target tooth is located is greater than the expected difficulty of removal and wearing, to obtain the first edge line of the orthodontic appliance.

[0137] In one possible implementation, the tooth feature data includes at least one of the following: crown height, undercut depth, crowding, rotation, buccal-lingual tilt, and arch morphology.

[0138] In one possible implementation, the method further includes: determining the edge line of the first orthodontic appliance based on at least one of the user's dental feature data and the performance data of the material used to manufacture the target orthodontic appliance.

[0139] In one possible implementation, the method further includes: establishing a first mapping relationship, the first mapping relationship including the relationship between at least one of preset tooth feature data and material performance data and a preset edge line; determining a first orthodontic appliance edge line based on the user's tooth feature data and at least one of the performance data of the material used to manufacture the user's orthodontic appliance, including: generating a first orthodontic appliance edge line based on the user's tooth feature data and at least one of the performance data of the material used to manufacture the user's orthodontic appliance, and the first mapping relationship.

[0140] In one possible implementation, the first mapping relationship also includes the relationship between a preset edge line and a preset removal force; determining the first orthodontic appliance edge line based on at least one of the user's dental feature data and the performance data of the material used to manufacture the user's orthodontic appliance includes: generating a first orthodontic appliance edge line that satisfies the user's expected removal force based on the user's dental feature data and the performance data of the material used to manufacture the user's orthodontic appliance, the user's expected removal force, and the first mapping relationship.

[0141] In one possible implementation, the tooth feature data also includes the degree of filling of the undercut between adjacent teeth. After obtaining the user's digital dental model, the method further includes: filling the undercut between adjacent teeth in the digital dental model; and determining the degree of filling of the undercut between adjacent teeth based on the filling status of the undercut between adjacent teeth.

[0142] In one possible implementation, the performance data of the material used to manufacture the user's orthodontic appliance includes at least one of the following: the material's thickness, the material's elastic modulus, and the material's flexural stiffness.

[0143] In a twelfth aspect, embodiments of this application provide a method for manufacturing an orthodontic appliance, comprising:

[0144] According to the edge line of the first orthodontic appliance, the orthodontic appliance to be cut corresponding to the digital tooth model is edge-cut to obtain the target orthodontic appliance; wherein, the edge line of the first orthodontic appliance is generated according to the method in the first aspect or any possible implementation of the first aspect, and the orthodontic appliance to be cut is obtained by pressing a membrane based on the solid tooth model corresponding to the digital jaw model.

[0145] In one possible implementation, the orthodontic appliance corresponding to the digital dental model is edge-cut according to the edge line of the first orthodontic appliance to obtain the target orthodontic appliance, including: forming a cutting indicator line on the orthodontic appliance to be cut according to the edge line of the first orthodontic appliance, the cutting indicator line being used to indicate the edge cutting path of the orthodontic appliance to be cut; and edge-cutting the orthodontic appliance to be cut according to the cutting indicator line to obtain the target orthodontic appliance.

[0146] In a thirteenth aspect, embodiments of this application provide a display method, including: displaying a user's digital dental model; and, in response to a command to generate a difficulty rating for wearing and removing the dental model, displaying the difficulty rating for wearing and removing the dental model.

[0147] In a fourteenth aspect, embodiments of this application provide a display method, including:

[0148] Displays the user's digital dental model;

[0149] The first orthodontic appliance edge line is shown, which is obtained according to the method in the first aspect or any possible implementation of the first aspect.

[0150] In a fifteenth aspect, embodiments of this application provide an edge line generation apparatus, comprising:

[0151] The acquisition unit is used to acquire the user's digital dental model.

[0152] The processing unit is used to determine the difficulty of removing and wearing the orthodontic appliance based on the user's tooth feature data extracted from the digital dental model, with the user's gingival margin as the edge line of the target appliance. The tooth feature data is used to characterize the morphological features of the user's teeth. Based on the difficulty of removing and wearing the appliance, the edge line of the target appliance is adjusted to obtain the first edge line of the appliance. The first edge line of the appliance is used to generate the edge morphology of the target appliance corresponding to the digital dental model, or the first edge line of the appliance is the edge morphology of the target appliance.

[0153] In a sixteenth aspect, embodiments of this application provide a display device, including a display unit and a processing unit:

[0154] The display unit is used to display the user's digital dental model;

[0155] The processing unit, in response to the generation command of the difficulty of wearing and removing the tooth, displays the difficulty of wearing and removing the tooth on the digital dental model via the display unit.

[0156] In a seventeenth aspect, embodiments of this application provide a display device, including a display unit, for:

[0157] Displays the user's digital dental model;

[0158] The first orthodontic appliance edge line is shown, which is obtained according to the method in the first aspect or any possible implementation of the first aspect.

[0159] In an eighteenth aspect, embodiments of this application also provide an electronic device comprising modules / units for performing method steps in any of the foregoing aspects or any possible implementations of any of the foregoing aspects. These modules / units may be implemented in hardware or by hardware executing corresponding software.

[0160] In a nineteenth aspect, embodiments of this application also provide a computer-readable storage medium storing computer-readable instructions that, when read and executed by a computer, cause the method described in any of the possible designs of the above-mentioned aspects to be implemented.

[0161] In a twentieth aspect, embodiments of this application also provide a computer program product, the computer program product including computer program code, which, when run on a computer, causes the computer to perform the method described in any of the possible designs of the foregoing aspects. Attached Figure Description

[0162] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying 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.

[0163] Figure 1 is a flowchart illustrating a method for adjusting a cutting path according to an embodiment of this application;

[0164] Figure 2 is a schematic diagram of single-point adjustment and segment adjustment provided in the embodiments of this application;

[0165] Figure 3 is a flowchart illustrating the process of determining the nth correction step that follows the i-th correction step, according to an embodiment of this application.

[0166] Figure 4 is a schematic diagram of the position information of each control point on the cutting path on the dental model provided in the embodiment of this application;

[0167] Figure 5 is a flowchart illustrating a method for generating a cutting line according to an embodiment of this application;

[0168] Figure 6 is a schematic diagram of the structure of a digital dental model provided in an embodiment of this application;

[0169] Figure 7 is a schematic diagram of a virtual tooth and initial cutting line provided in an embodiment of this application;

[0170] Figure 8 is a flowchart illustrating a method for determining a bounding box according to an embodiment of this application;

[0171] Figure 9 is a structural schematic diagram of a bounding box provided in an embodiment of this application;

[0172] Figure 10 is a flowchart illustrating a method for generating a third region sub-line according to an embodiment of this application;

[0173] Figure 11 is a schematic diagram of a virtual tooth and initial cutting line provided in an embodiment of this application;

[0174] Figure 12 is a schematic diagram of an updated cutting line provided in an embodiment of this application;

[0175] Figure 13 is a flowchart of a method for determining the cutting line of an orthodontic appliance according to an embodiment of the present invention;

[0176] Figure 14 is a flowchart of a method for determining an initial cutting line according to an embodiment of the present invention;

[0177] Figure 15 is a schematic diagram of a dental model provided in an embodiment of the present invention;

[0178] Figure 16 is a schematic diagram of contour information provided in an embodiment of the present invention;

[0179] Figure 17 is a schematic diagram of an initial cutting line provided in an embodiment of the present invention;

[0180] Figure 18 is a flowchart of a method for determining the cutting line of an orthodontic appliance according to an embodiment of the present invention;

[0181] Figure 19 is a schematic diagram of an alternative point provided in an embodiment of the present invention;

[0182] Figure 20 is a schematic diagram of a cutting line of an orthodontic appliance provided in an embodiment of the present invention;

[0183] Figure 21 is a schematic diagram of the structure of an orthodontic appliance provided in an embodiment of the present invention;

[0184] Figure 22 is a schematic diagram of a cutting line adjustment process provided in some embodiments of this application;

[0185] Figure 23 is a schematic diagram of the placement and dislocation of a dental instrument provided in some embodiments of this application;

[0186] Figure 24 is a schematic diagram of a tooth and gum provided in some embodiments of this application;

[0187] Figure 25 is a schematic diagram of the overall adjustment of a cutting line provided in some embodiments of this application;

[0188] Figure 26 is a schematic diagram of a partial adjustment of a cutting line provided in some embodiments of this application;

[0189] Figure 27 is a schematic diagram of a first projection line and a second projection line corresponding to a single tooth provided in some embodiments of this application;

[0190] Figure 28a is a schematic diagram of the actual projection of the outermost contour of multiple teeth in the crown region according to some embodiments of this application;

[0191] Figure 28b is a schematic diagram of a second projection line corresponding to multiple teeth provided in some embodiments of this application;

[0192] Figure 29 is a schematic diagram of the first and second projection lines corresponding to another single tooth provided in some embodiments of this application;

[0193] Figure 30 is a schematic diagram of a first projection line and a second projection line corresponding to multiple teeth provided in some embodiments of this application;

[0194] Figure 31 is a schematic diagram of the different tooth placement directions corresponding to a dental instrument provided in some embodiments of this application;

[0195] Figure 32 is a schematic diagram of a projection plane and a positioning direction provided by some embodiments of this application;

[0196] Figure 33 is a schematic diagram of the gingival margin of a user's teeth provided in an embodiment of this application;

[0197] Figure 34 is a flowchart illustrating an edge line generation method provided in an embodiment of this application;

[0198] Figure 35 is a schematic diagram of the undercut provided in an embodiment of this application;

[0199] Figure 36 is a comparative schematic diagram of the dental arch contour provided in the embodiments of this application;

[0200] Figure 37 is a schematic diagram of the edge line of the orthodontic appliance provided in the embodiment of this application;

[0201] Figure 38 is a flowchart illustrating a display method provided in an embodiment of this application;

[0202] Figure 39 is a flowchart illustrating another display method provided in an embodiment of this application;

[0203] Figure 40 is a schematic diagram of the structure of a cutting path adjustment device provided in an embodiment of this application;

[0204] Figure 41 is a schematic diagram of a cutting line generation device provided in an embodiment of this application;

[0205] Figure 42 is a schematic diagram of a device for determining the cutting line of an orthodontic appliance according to an embodiment of the present invention;

[0206] Figure 43 is a schematic diagram of a cutting line adjustment device provided in some embodiments of this application;

[0207] Figure 44 is a schematic diagram of an edge line generation device provided in an embodiment of this application;

[0208] Figure 45 is a schematic diagram of the structure of a display device provided in an embodiment of this application;

[0209] Figure 46 is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. Detailed Implementation

[0210] To make the objectives, technical solutions, and advantages of this application clearer, the application will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0211] In the embodiments of this application, "multiple" refers to two or more. Terms such as "first" and "second" are used only for descriptive purposes and should not be construed as indicating or implying relative importance or order.

[0212] This application can be applied to a three-dimensional modeling system for digital orthodontic appliances. Before implementing the technical solution of this application, the patient's dental and jaw data is first obtained through an oral scanning device. Then, a three-dimensional dental and jaw model is generated based on the patient's dental and jaw data. Finally, the initial cutting path for each orthodontic step is generated according to the treatment plan.

[0213] Figure 1 is a flowchart illustrating a method for adjusting a cutting path according to an embodiment of this application. As shown in Figure 1, the method includes:

[0214] Step 101: Receive adjustment instructions for the first cutting path.

[0215] In this embodiment, the first cutting path is the cutting path corresponding to the tooth model in the i-th orthodontic step, and the i-th orthodontic step is the current adjustment step. Adjustment commands can be issued by the operator through mouse clicks, drags, or other operations on the design interface. For example, if the operator finds that the cutting path of the tooth model in the 5th orthodontic step does not meet the actual orthodontic needs in a certain area, they can click or select that area on the design interface and choose to manually drag or automatically adjust the cutting path of that area. The system will then receive an adjustment command for the cutting path of the specified area in the 5th orthodontic step.

[0216] The adjustment command can be a single-point adjustment command or a segment adjustment command. A single-point adjustment command refers to adjusting only one control point, as shown in Figure 2-1; a segment adjustment command refers to adjusting a local cutting path formed by multiple control points, as shown in Figure 2-2. If the adjustment command is a single-point adjustment command, then receiving the adjustment command for the first cutting path includes: receiving a single-point adjustment command for the fifth control point on the first cutting path. The single-point adjustment command is triggered by a first operation on the fifth control point. The first operation can be triggered by a mouse, keyboard, touch screen, etc., or it can be triggered by voice. This application does not specifically limit this. Taking a mouse as an example, the first operation can be that the operator drags the fifth control point from its original position to a new position using the mouse, or the operator clicks to select the fifth control point and then clicks again to move the fifth control point to the desired position. This application does not specifically limit this.

[0217] If the adjustment command is a segment adjustment command, then receiving the adjustment command for the first cutting path includes: receiving the segment adjustment command for the first cutting path, whereby the segment adjustment command is triggered by a second operation. The second operation can be triggered by a mouse, keyboard, touchscreen, or voice; this application does not specifically limit this. Taking a mouse and keyboard as examples, the second operation could be that the operator presses and holds down a key (e.g., Ctrl, Alt) while dragging the cutting path of a segment to a new position using the mouse; or the operator presses and holds down a key (e.g., Ctrl, Alt) while clicking the cutting path of a segment and then clicking the desired position again. This application does not specifically limit this. When dragging or moving the cutting path of a segment to a new position, the entire cutting path of that segment can be adjusted by directly selecting the cutting path of that segment, or only a control point on the cutting path can be selected, and the system determines the segment that moves with that control point.

[0218] Step 102: Adjust the first cutting path according to the adjustment instructions.

[0219] Specifically, if the adjustment instruction is a single-point adjustment instruction, the first cutting path is adjusted according to the adjustment instruction, including: adjusting the fifth control point according to the single-point adjustment instruction. The system can change the adjusted coordinate value of the fifth control point according to the single-point adjustment instruction, thereby completing the single-point adjustment of the fifth control point on the first cutting path.

[0220] If the adjustment instruction is a segment adjustment instruction, the first cutting path is adjusted according to the instruction, including: adjusting the third sub-cutting path of the corresponding segment of the first cutting path according to the segment adjustment instruction. The system can change the adjusted coordinate values ​​of each control point on the third sub-cutting path according to the segment adjustment instruction, and use the line connecting the adjusted control points as the adjusted third sub-cutting path, thereby completing the segment adjustment of the third sub-cutting path of the corresponding segment of the first cutting path. The third sub-cutting path can be the adjusted segment on the first cutting path indicated in the segment adjustment instruction, or it can be the adjusted segment calculated by the system based on the first control point selected in the segment adjustment instruction.

[0221] For example, if the third sub-cutting path is an adjustment segment calculated based on the first control point selected in the segment adjustment instruction, then the adjusted three-dimensional coordinates of the other control points on the third sub-cutting path can be determined first based on the three-dimensional coordinates of the first control point and other control points on the third sub-cutting path before adjustment, the maximum squared distance between the first control point and other control points on the third sub-cutting path, and the adjusted three-dimensional coordinates of the first control point. For example, for each other control point P on the third sub-cutting path... i The adjusted coordinates P of other control points on the third sub-cutting path can be determined using Formula 1. i ′:

[0222] Among them, P i ′ represents the adjusted 3D coordinates of other control points on the third sub-cutting path; P i P0 represents the 3D coordinates of the first control point before adjustment, while P0' represents the 3D coordinates of the other control points on the third sub-cutting path before adjustment. P0' represents the 3D coordinates of the first control point after adjustment. d represents the coordinates of the first control point P0 relative to other control points P0. i The maximum squared distance.

[0223] Step 103: Based on the adjustment range and adjustment magnitude of the first cutting path, adjust the second cutting path of the dental model for n orthodontic steps accordingly.

[0224] Where n is a positive integer greater than or equal to 1. The n orthodontic steps are the orthodontic steps related to the i-th orthodontic step. Based on the adjustment range and adjustment magnitude of the first cutting path, the second cutting path of the dental model of the n orthodontic steps is adjusted accordingly to achieve the effect of cutting path adjustment.

[0225] The n orthodontic steps can be a pre-defined number of orthodontic steps that follow the i-th orthodontic step. For example, if n equals 5, then after adjusting the first cutting path of the i-th orthodontic step, the second cutting paths of the dental models for the (i+1), (i+2), (i+3), (i+4), and (i+5)-th orthodontic steps will also be adjusted accordingly. It should be noted that this application does not specifically limit the sequential relationship between the n orthodontic steps and the i-th orthodontic step; for example, the second cutting paths of the dental models for the (i-2), (i-1), (i+1), (i+2), and (i+3)-th orthodontic steps can also be adjusted accordingly.

[0226] The n orthodontic steps can also be the number of orthodontic steps that follow the i-th orthodontic step calculated by the system. Before adjusting the second cutting path of the tooth and jaw model of the n orthodontic steps accordingly in step 103, the method further includes: determining the n orthodontic steps that follow the i-th orthodontic step based on the similarity between the first cutting path of the i-th orthodontic step and the second cutting paths of the other orthodontic steps.

[0227] In the above technical solution, n correction steps that follow the i-th correction step are determined based on the similarity of the cutting path. Then, the n correction steps that have high similarity to the i-th correction step in terms of cutting path features are adjusted accordingly, making the adjustment of the cutting path more targeted and accurate.

[0228] For example, Figure 3 is a flowchart illustrating how to determine n correction steps that follow the i-th correction step based on the similarity between the first cutting path of the i-th correction step and the second cutting paths of the other correction steps, according to an embodiment of this application. As shown in Figure 3, the method includes the following steps:

[0229] Step 301: Determine the first sub-cutting path within the adjustment range indicated by the adjustment command from the first cutting path.

[0230] Step 302: For each of the other correction steps, determine the second sub-cutting path that has the same adjustment range from the second cutting paths of the other correction steps.

[0231] In one possible implementation, determining a second sub-cutting path with the same adjustment range from the second cutting paths of other orthodontic steps includes: obtaining the position information of each first control point within the first sub-cutting path on the dental model; determining each second control point in the second cutting paths of other orthodontic steps that has the same position information as the first control points; and using the path formed by each second control point as the second sub-cutting path. The position information may include the region where the control point is located on the dental model (e.g., in the maxilla or mandible; labial or lingual), the tooth number at the location of the control point, etc.

[0232] In the above technical solution, by obtaining the position information of each first control point within the first sub-cutting path on the dental model, second control points with the same position information are determined in the second cutting paths of other orthodontic steps, thus forming a second sub-cutting path. This method ensures that the second sub-cutting path corresponding to the first sub-cutting path can be accurately found in the cutting paths of different orthodontic steps, providing a basis for subsequent accurate similarity calculation and reasonable adjustment of the cutting path, and improving the accuracy and consistency of cutting path adjustment.

[0233] For example, the positional information of each control point on the cutting path on the dental model can be established as follows: For each control point on the cutting path, determine the tooth or gingiva closest to the control point; if the closest control point is a tooth, then set the positional information of the control point to the tooth's sequence number; if the closest control point is the gingiva, then determine the positional information of the control point based on the positional information of the third control point before the control point and the positional information of the fourth control point after the control point. Here, the third control point is the first control point before the control point whose positional information is the tooth's sequence number, and the fourth control point is the first control point after the control point whose positional information is the tooth's sequence number.

[0234] For example, for any control point p on the cutting path, if the closest point to control point p is a tooth, then the position information of control point p is set to the tooth's index, i.e., f(p) = tooth index; if the closest point to control point p is the gum, then f(p) is set to the first value, for example, f(p) = 0. The labels of each control point on the cutting path are shown in Figure 4-1. Then, points with f(p) = 0 are filtered out. For any point with f(p) = 0, the first point p1 with f(p) not equal to 0 (f(p) != 0) is searched forward, and the first point p2 with f(p) not equal to 0 (f(p) != 0) is searched backward. The label of point p is updated based on the position information of p and p2. For example, the label of point p is updated to f(p) = 100 * min(f(p1), f(p2)) + max(f(p1), f(p2)). Referring to 4-2 in Figure 4, the labels for teeth 3 and 4 are 0. The first non-zero point before teeth 3 and 4 is labeled as tooth 3, with a label of 31. The first non-zero point after teeth 3 and 4 is labeled as tooth 5, with a label of 32. Therefore, the labels for teeth 3 and 4 are updated to 3132. After obtaining the final labels for each control point on the cutting path, control points with the same label can be used as control points with the same adjustment range. That is, control points with the same label as the first control point are used as the second control points.

[0235] The above technical solution establishes the position information of each control point on the cutting path on the dental model. This method can accurately locate each control point on the cutting path on the dental model, providing an important foundation for achieving precise matching and adjustment between sub-cutting paths of different orthodontic steps, and helping to improve the accuracy and reliability of the entire cutting path adjustment method.

[0236] Step 303: Calculate the similarity between the first sub-cutting path and the second sub-cutting path.

[0237] Step 304: Select the n correction steps with similarity greater than the set threshold as the n correction steps that follow the i-th correction step.

[0238] Traverse the other correction steps around the i-th correction step. If the similarity between the first sub-cutting path of the i-th correction step and the second sub-cutting path of another correction step is greater than a set threshold, then the correction step is used as the correction step that follows the i-th correction step. The search stops when the similarity between the first sub-cutting path of the i-th correction step and the second sub-cutting path of another correction step is greater than a set threshold. Then, the n correction steps with similarity greater than the set threshold are used as the n correction steps that follow the i-th correction step.

[0239] In the above technical solution, a first sub-cutting path within the adjustment range is determined from the first cutting path, and a second sub-cutting path within the corresponding range is found in the second cutting paths of other correction steps. The similarity between the two is then calculated, and correction steps with a similarity greater than a set threshold are taken as follow-up correction steps. This method makes the process of determining follow-up correction steps more precise and quantifiable, and can more accurately screen correction steps with similar cutting path characteristics to the i-th correction step, thereby ensuring the effectiveness and accuracy of subsequent adjustments to the cutting paths of these correction steps.

[0240] In step 103, if the adjustment instruction is a single-point adjustment instruction, the second cutting path of the dental model with n orthodontic steps is adjusted accordingly based on the adjustment range and adjustment magnitude of the first cutting path. This includes: adjusting the sixth control point of the dental model with n orthodontic steps accordingly based on the adjustment magnitude of the fifth control point, wherein the sixth control point is the control point in the n orthodontic steps that corresponds to the fifth control point.

[0241] In one possible implementation, based on the adjustment range of the fifth control point, the sixth control point of the dental model for n orthodontic steps is adjusted accordingly, including the following steps:

[0242] Step a: Determine the index of the triangular facet on the 3D mesh where the fifth control point is located after adjustment.

[0243] The three-dimensional mesh is either a three-dimensional mesh representing teeth or a three-dimensional mesh representing gums. The three-dimensional mesh includes multiple triangular facets, each of which has its own index. The corresponding triangular facet can be found through the index.

[0244] Step b: Calculate the first position of the fifth control point on the triangular face after adjustment.

[0245] Step c: For each correction step, adjust the position of the sixth control point to the first position on the triangular facet corresponding to the same index.

[0246] In the above technical solution, by determining the index of the triangular facet on the three-dimensional mesh where the fifth control point of the i-th correction step is located after adjustment and the position on the triangular facet, the sixth control points of n correction steps are adjusted to the same position on the triangular facet with the same index. This method makes the adjustment of control points in three-dimensional space more precise and operable, and ensures the consistency and accuracy of single-point adjustment between different correction steps.

[0247] In step 103, if the adjustment instruction is a segment adjustment instruction, the second cutting path of the dental model of n orthodontic steps is adjusted accordingly based on the adjustment range and adjustment magnitude of the first cutting path. This includes: adjusting the second sub-cutting path of the dental model of n orthodontic steps according to the adjustment magnitude of the third sub-cutting path within the adjustment range of the first cutting path. The second sub-cutting path is a sub-cutting path in the n orthodontic steps with the same adjustment range as the third cutting path.

[0248] After calculating the adjusted 3D coordinates of the other control points on the third sub-cutting path based on Formula 1 above, the control points on the second sub-cutting path of the dental model for n orthodontic steps are adjusted accordingly based on the adjustment range of each control point on the third sub-cutting path. Specifically, the index of the triangular facet on the 3D mesh where each control point on the third sub-cutting path is located after adjustment is first determined, and then the position of each control point on the triangular facet after adjustment is calculated. Then, for each orthodontic step, the position of each control point on the second sub-cutting path is adjusted to the same position on the triangular facet corresponding to the same index.

[0249] The above technical solution enables the follow-up adjustment of the cutting path segment by n correction steps. It receives a segment adjustment instruction for the first cutting path and adjusts the third sub-cutting path of the corresponding segment. Simultaneously, based on this, it adjusts the second sub-cutting path with the same adjustment range among the n correction steps accordingly. This method allows the adjustment of the cutting path segment to be effectively transmitted and applied among multiple related correction steps, facilitating the overall optimization and coordination of the cutting paths across multiple correction steps.

[0250] With the continuous development of digital technology in oral healthcare, computer-aided orthodontic treatment has been widely applied. Among the key steps in computer-aided orthodontic treatment, obtaining virtual tooth cutting lines from a complete digital dental model is crucial, directly impacting treatment planning and outcomes.

[0251] The current process of obtaining the cutting lines of virtual teeth generally involves manually drawing or adjusting the initial cutting line data corresponding to the virtual teeth on a digital dental model based on the experience of the design dentist. However, the accuracy of this method depends on the dentist's experience level, and it is difficult to guarantee accuracy and is inefficient.

[0252] Therefore, how to accurately and efficiently determine the cutting line of the virtual tooth remains to be solved.

[0253] Figure 5 is a flowchart illustrating a method for generating a cutting line according to an embodiment of this application. This method can be executed by a cutting line generating device, which can be a terminal device or a module for a terminal device, or a server or a module for a server. This application does not limit the subject of execution of this method.

[0254] The method includes the following steps:

[0255] Step 501: Obtain the initial cutting lines for the entire tooth and gingiva in the digital dental model.

[0256] Optionally, a digital dental model can be obtained by scanning the patient's oral cavity. In practical applications, a plaster model of the patient's teeth and jaw can be made first, and then a digital dental model can be obtained by scanning the plaster model. The specific choice can be made according to the actual application scenario, and no limitation is made here.

[0257] Optionally, the digital dental model can be a triangular patch model as shown in Figure 6. It can be seen that the triangular patch model in Figure 6 includes a mesh composed of numerous triangular patches, each of which includes vertices and edges. The dashed lines composed of black dots are the initial cutting lines, used to distinguish between the crown and gingiva in the digital dental model.

[0258] In one possible implementation, the initial cutting line is determined based on the intersection line of the triangular facet model of the crown region and the triangular facet model of the gingival region in the digital dental model.

[0259] In another possible implementation, the initial cutting line is drawn manually. This application does not limit the method for determining the initial cutting line.

[0260] Step 502: Determine a first sub-line of the region located in the virtual tooth region of the digital dental model and a second sub-line of the region located in the real tooth region adjacent to the virtual tooth from the initial cutting line.

[0261] Optionally, the real teeth adjacent to the virtual tooth are the nearest real teeth on both sides of the virtual tooth, or the real teeth adjacent to the virtual tooth are the real teeth on one side of the virtual tooth.

[0262] Specifically, a virtual tooth refers to a computer-simulated cavity resembling a tooth, designed to fill large gaps between two real teeth, complete the shape of a missing tooth, or reserve space for emerging teeth. Reasons for large gaps between two real teeth include: missing real teeth, extraction of real teeth, no missing teeth between two real teeth, and extraction of teeth with excessively large gaps.

[0263] Since the quality of virtual teeth generation is uncontrollable, that is, sometimes the effect of the generated virtual teeth is very different from that of real teeth, the first sub-line of the virtual tooth area in the digital dental model cannot accurately reflect the cutting line of the virtual tooth area. Therefore, it is necessary to adjust the first sub-line of the virtual tooth area.

[0264] Optionally, as shown in Figure 7, the teeth in Figure 7 represent virtual teeth, the dashed lines composed of points outside the cuboid are the initial cutting lines, and the dashed lines composed of points inside the cuboid are the first region sub-lines. As shown in Figure 7, the first region sub-lines cannot correctly distinguish between the teeth and gums in the virtual tooth region.

[0265] Step 503: Based on the second region sub-line, adjust the first region sub-line to obtain an updated cutting line.

[0266] The above solution, on the one hand, can automatically determine the cutting line of the virtual tooth without the need for manual drawing or adjustment of the initial cutting line corresponding to the virtual tooth, thus improving the efficiency of determining the cutting line of the virtual tooth region; on the other hand, since virtual teeth often have similar features to their adjacent real teeth, adjusting the first sub-line using the second sub-line of the adjacent real tooth region can accurately and effectively determine the cutting line of the virtual tooth region.

[0267] In one possible implementation, the method for determining the first region sub-line of the virtual tooth region in the digital dental model from the initial cutting line in step 502 is shown in Figure 8, and includes the following steps:

[0268] Step 801: Using the centroid of the crown of the virtual tooth in the digital dental model as the origin, extend outward along the axis of the world coordinate system.

[0269] Optionally, the origin can be taken as the center of the crown of the virtual tooth in the digital dental model, and extended outward along the axis of the world coordinate system. This application does not limit this.

[0270] Optionally, the virtual tooth may extend outward along the axis of its own coordinate system; this application does not limit this.

[0271] Optionally, the local coordinate system of the virtual tooth can be transformed to a global coordinate system, with the centroid as the origin, and the coordinate axes extended outward based on the transformed coordinate system. This application does not limit this.

[0272] Step 802: Determine three intersection points based on the intersection positions of the outwardly extending world coordinate axis and the surface of the crown of the virtual tooth.

[0273] Optionally, each axis intersects the virtual tooth at two points (positive axis direction and negative axis direction), and the distance from the origin to the origin is selected from the intersection point that is farther away from the origin (i.e., the centroid) as half of the initial length of the bounding box in that direction.

[0274] Optionally, the initial length in each direction is multiplied by a magnification factor to determine the final length of the bounding box.

[0275] Step 803: The cuboid formed by extending the three intersection points outward is defined as the bounding box of the virtual tooth.

[0276] Optionally, Figure 9 shows the bounding box of the virtual tooth.

[0277] In one possible implementation, for a series of consecutive virtual teeth, a bounding box is determined for each virtual tooth, that is, each virtual tooth corresponds to a bounding box, and multiple consecutive virtual teeth correspond to multiple bounding boxes.

[0278] In another possible implementation, a bounding box is determined for a series of consecutive virtual teeth, that is, a bounding box corresponds to a series of consecutive virtual teeth.

[0279] One possible implementation method for determining a bounding box for multiple consecutive virtual teeth includes: determining a bounding box for each virtual tooth, connecting the bounding boxes corresponding to each virtual tooth, and determining a bounding box for multiple consecutive virtual teeth.

[0280] One possible implementation method for determining a bounding box for a series of virtual teeth includes: determining the center of the series of virtual teeth as the origin and extending it outward along the axis of the world coordinate system; determining three intersection points based on the intersection positions of the outwardly extending world coordinate axis and the crown surfaces of the series of virtual teeth; and defining the cuboid formed by extending the three intersection points outward as the bounding box of the series of virtual teeth.

[0281] Step 804: The initial cutting line located within the bounding box is determined as the first region sub-line located in the virtual tooth region of the digital dental model.

[0282] The above scheme can accurately and effectively determine the bounding box of the virtual tooth.

[0283] In one possible implementation, for the real teeth adjacent to the virtual tooth being the closest real teeth on both sides of the virtual tooth, step 502 above determines the second region sub-line from the initial cutting line to the region of the real teeth adjacent to the virtual tooth, including: taking the region sub-line corresponding to the real tooth within a set distance to the left of the first region sub-line in the initial cutting line as the second region sub-line on the left; and taking the region sub-line corresponding to the real tooth within a set distance to the right of the first region sub-line in the initial cutting line as the second region sub-line on the right.

[0284] Optionally, the distance is set to the number of adjacent real teeth; for example, the distance is set to 1, and the region sub-line corresponding to a real tooth on the left side of the first region sub-line in the initial cutting line is taken as the second region sub-line on the left; or, the distance is set to 2, and the region sub-line corresponding to two real teeth on the left side of the first region sub-line in the initial cutting line is taken as the second region sub-line on the left.

[0285] Optionally, the distance is set to the length of the first region sub-line; for example, the distance is set to 1 cm, and the region sub-line corresponding to the actual tooth 1 cm to the left of the first region sub-line in the initial cutting line is taken as the second region sub-line on the left.

[0286] Optionally, the distance is set as the sampling rate of the initial cutting line; for example, if the distance is set to 10 points, the initial cutting line is sampled according to the sampling rate, and the region sub-line corresponding to the real tooth located within 10 sampling points to the left of the first region sub-line in the initial cutting line is taken as the second region sub-line on the left.

[0287] This application does not limit the choice of the set distance.

[0288] In one possible implementation, for the real teeth adjacent to the virtual tooth being real teeth on one side of the virtual tooth, step 502 above determines a second region sub-line from the initial cutting line that is located in the region of the real teeth adjacent to the virtual tooth, including: taking the region sub-line corresponding to the real teeth located within a set distance to the left or right of the first region sub-line in the initial cutting line as the second region sub-line.

[0289] In one possible implementation, taking the real teeth adjacent to the virtual tooth as the nearest real teeth on both sides of the virtual tooth as an example, the method for adjusting the first region sub-line based on the second region sub-line in step 503 above is shown in Figure 10, and includes the following steps:

[0290] Step 1001: Determine the relative low point in the second region sub-line.

[0291] Among them, the points closer to the gum line in the sub-region are lower.

[0292] In one possible implementation, the relative low point is the lowest point in the second region sub-line. Alternatively, multiple points can be selected near the lowest point in the second region sub-line, and the relative low point in the second region sub-line can be determined based on the weighted values ​​of these multiple points.

[0293] In another possible implementation, the lowest point in the second sub-line within a set distance is selected as the relative low point in the second sub-line; or, within the set distance, multiple points are selected from the second sub-line, and the relative low point in the second sub-line is determined based on the weighted value of the multiple points.

[0294] In another possible implementation, a relative low point in the second region sub-line is determined based on the curvature of the second region sub-line; for example, a point where the curvature of the second region sub-line is close to 0 is determined as a relative low point in the second region sub-line.

[0295] Step 1002: Determine the edge points and midpoints in the first region sub-line.

[0296] The coordinates of the midpoint in the root direction are determined based on the coordinates of the relative low point in the root direction.

[0297] In one possible implementation, the first and last points in the first region sub-line are determined as edge points in the first region sub-line; based on the coordinate values ​​of the first and last points on the tooth surface, the coordinate values ​​of the middle point on the tooth surface are determined.

[0298] In one possible implementation, determining the relative low point in the second region sub-line includes: determining the lowest point in the second region sub-line on the left as the relative low point on the left; and determining the lowest point in the second region sub-line on the right as the relative low point on the right.

[0299] In one possible implementation, the coordinates of the intermediate point in the root direction are determined based on the coordinates of the relative low point in the root direction, including: determining the coordinates of the intermediate point in the root direction based on the coordinates of the relative low point on the left and the relative low point on the right in the root direction.

[0300] Specifically, for virtual teeth on either side of the lips or tongue, a first starting point and a second starting point are determined based on the first region sub-line corresponding to the virtual tooth. The first starting point and the second starting point are located at the beginning and end of the first region sub-line corresponding to the virtual tooth, respectively. As shown in Figure 11, points A and B are the first and second starting points on the labial side of the virtual tooth, and points C and D are the first and second starting points on the lingual side of the virtual tooth.

[0301] The lowest point on the second sub-line corresponding to the adjacent real tooth on the left side of the virtual tooth, with a distance less than a set distance from the first starting point, is selected as the third starting point; the lowest point on the second sub-line corresponding to the adjacent real tooth on the right side of the virtual tooth, with a distance less than a set distance from the second starting point, is selected as the fourth starting point; the third and fourth starting points are respectively located on the second sub-lines corresponding to the adjacent real teeth on the left and right sides of the virtual tooth; the third starting point and the first starting point are located on the same side of the virtual tooth; the fourth starting point and the second starting point are located on the same side of the tooth. As shown in Figure 11, point M is the third starting point and point N is the fourth starting point.

[0302] Determine the first midpoint between the first starting point and the second starting point, and determine the second midpoint between the third starting point and the fourth starting point; determine the X-axis and Y-axis data of the midpoint based on the X-axis and Y-axis data of the first midpoint, and determine the Z-axis data of the midpoint based on the Z-axis data of the second midpoint; project the midpoint onto the surface of the virtual tooth. As shown in Figure 11, point P is the midpoint projected onto the surface of the virtual tooth crown.

[0303] In one possible implementation, the intermediate point is determined to be located above the neck of the virtual tooth and not exceeding the virtual tooth itself. If the intermediate point is located below the neck of the virtual tooth or above the highest point of the virtual tooth, the intermediate point is redefined.

[0304] Optionally, redetermining the intermediate point includes: updating the set distance, redetermining the relative low point in the second region sub-line, and updating the intermediate point based on the redetermined relative low point in the second region sub-line.

[0305] Optionally, redetermining the intermediate point includes: selecting a relative low point of the first region sub-line as a relative low point in the second region sub-line; and updating the intermediate point based on the redetermined relative low point in the second region sub-line.

[0306] Optionally, redetermining the intermediate point includes: manually marking relative low points and updating the intermediate point based on the redetermined relative low points in the second region sub-line.

[0307] This application does not limit the method for redetermining the intermediate point.

[0308] Step 1003: Generate a third region sub-line based on the edge points and the midpoints.

[0309] The third region sub-line is used to replace the first region sub-line.

[0310] The above scheme can accurately determine the center position of the virtual tooth based on the beginning and end points of the first sub-line. For a single tooth, the relative low point of the crown and gingival dividing line is often located at the center of the crown surface. Therefore, the relative low point in the second sub-line can accurately reflect the coordinate value of the midpoint in the root direction, thereby accurately and effectively determining the coordinate value of the cutting line of the virtual tooth in the root direction.

[0311] In one possible implementation, for the real teeth adjacent to the virtual tooth, which are the real teeth on one side of the virtual tooth, in step 503 above, the adjustment of the first region sub-line based on the second region sub-line is similar to steps 1001 to 1003 above, and will not be repeated here. However, if the virtual tooth on one side within the set distance includes multiple real teeth, then the relative low point in the second region sub-line is determined according to the weighted value of the lowest point of the multiple real teeth.

[0312] In one possible implementation, the edge points and the intermediate points are connected and the connection is smoothed; the smoothed connection is sampled according to the sampling rate of the initial cutting line to obtain each sampling point; and a third region sub-line is generated based on each sampling point.

[0313] Specifically, a shortest path passing through the edge point and the midpoint is found in the digital dental model. This shortest path is sampled according to the sampling rate of the initial cutting line, and the sampled points are mapped one by one to the positions corresponding to the initial cutting line. The third sub-line corresponding to the virtual tooth is connected to the second sub-line of the adjacent real tooth region. Simultaneously, the cutting lines on both sides of the starting position of the virtual tooth are smoothed to ensure the updated cutting lines are smooth. The updated cutting lines are shown in Figure 12. As can be seen from Figure 12, the cutting lines that were originally located on the surface of the virtual tooth crown are now located between the crown and the gingiva of the virtual tooth.

[0314] The above scheme samples the smoothed lines according to the sampling rate of the initial cutting line, which can ensure that the sub-lines of the third region and the sub-lines of the second region have the same sampling rate, thereby ensuring that the updated cutting lines have a uniform sampling rate.

[0315] In one possible implementation, after step 503 above, the method further includes: displaying the updated cutting lines. Displaying the updated cutting lines helps humans understand the generation effect of the virtual tooth cutting lines.

[0316] Optionally, one or more of the following may also be displayed: the initial cutting line, the bounding box of the virtual teeth, the relative low point in the second region sub-line, the edge point and midpoint of the second region sub-line, and the third region sub-line.

[0317] In orthodontic treatment, precise fitting of the aligners is crucial for effective treatment. With the widespread application of invisible aligner technology, the rational design of the incision lines plays a decisive role in the fit and stability of the aligners to the teeth.

[0318] Currently, traditional orthodontic appliance cut lines are typically designed to fit snugly against the gum line. However, this type of cut line is not suitable for patients with short crowns. Because patients with short crowns often have incompletely developed erupted teeth or have only a small portion of the crown remaining, the cut lines created using traditional methods result in insufficient coverage by the appliance, making it impossible to achieve effective fixation between the appliance and the teeth.

[0319] In summary, how to adjust the cutting lines of the orthodontic appliance to make the cutting lines more effective in wrapping the appliance is a technical problem that urgently needs to be solved.

[0320] Orthodontics, as a leading technology in the international orthodontic field, involves several steps when a patient undergoes orthodontic treatment. First, the dentist creates a three-dimensional model of the patient's jaw based on their oral condition. Then, a virtual orthodontic system analyzes and processes this digital model. Finally, using technologies such as 3D printing, custom-made aligners are created to straighten the teeth. In the virtual orthodontic system, the segmentation of teeth and gums is a crucial element. The accuracy of this segmentation directly affects the scientific validity of the treatment plan and the fit of the aligners, playing a decisive role in the overall orthodontic outcome.

[0321] Figure 13 shows a flowchart of a method for determining the cutting line of an orthodontic appliance according to an embodiment of the present invention. The method includes the following steps:

[0322] Step 1301: Determine the initial cutting line using a dental model.

[0323] In this embodiment of the invention, the initial cutting line needs to be determined first, and then adjusted to accurately determine the orthodontic appliance cutting line. The initial cutting line is the tooth-gingival boundary line that closely follows the gum line. The following describes how to determine the initial cutting line using a dental model.

[0324] Figure 14 shows a flowchart of a method for determining an initial cutting line according to an embodiment of the present invention. The method includes the following steps:

[0325] Step 1401: Using a dental model, determine the contour information between each tooth crown and the gingiva.

[0326] In this embodiment of the invention, the patient's dental data is first obtained by scanning the patient's teeth and jaw with an oral scanning device, and then a dental model is generated based on the patient's dental data, as shown in Figure 15.

[0327] Using a dental model, the contour information between each tooth crown and the gingiva is determined. The contour information is continuous curve data, as shown in Figure 16.

[0328] Step 1402: Based on the contour information between each tooth crown and the gingiva, sample each initial point.

[0329] In this embodiment of the invention, specifically, the overlapping portions of the contour information between the crowns and gingiva of two adjacent teeth are deleted, and the remaining contour information is sampled to obtain initial points. Various sampling methods can be used, including uniform sampling, adaptive sampling, or other methods, which are not limited here. In one possible case, if the sampling method is uniform sampling, points are selected at fixed intervals at equal distances on the remaining contour information as initial points.

[0330] In another possible scenario, if the sampling method is adaptive sampling, the sampling interval is dynamically adjusted, and points are selected from the remaining contour information as initial points.

[0331] Step 1403: Perform curve fitting on each initial point to obtain the initial cutting line.

[0332] In this embodiment of the invention, curve fitting is performed on each initial point to connect the discrete initial points into a smooth and continuous curve, which is the initial cutting line, as shown in Figure 17.

[0333] As can be seen from steps 1401 to 1403 above, the initial cutting line can be determined more accurately using the dental model, which facilitates subsequent adjustments to the initial cutting line to obtain a cutting line for the orthodontic appliance with better coverage.

[0334] Step 1302: Based on the adjustment information of the initial cutting line, obtain the orthodontic cutting line through the initial cutting line.

[0335] In this embodiment of the invention, during orthodontic treatment, some patients have short tooth crowns, and because the erupting teeth are not fully developed and the crown portion of the residual roots and crowns is small, if the orthodontic appliance is directly generated according to the initial cutting line, the appliance will not cover the teeth sufficiently when the patient wears it. This will prevent the appliance from forming an effective fixation between the appliance and the teeth, leading to loosening and displacement of the appliance. This not only affects the accurate transmission of orthodontic force and prolongs the orthodontic treatment period, but may also cause oral discomfort in the patient, or even cause the appliance to fall off, seriously interfering with the treatment process.

[0336] To address the aforementioned issues, this application adjusts the initial cutting line based on adjustment information to obtain the orthodontic appliance cutting line. The adjustment information indicates the range of adjustment of the initial cutting line towards the gingiva.

[0337] When selecting the cutting line for the orthodontic appliance, it is important to consider that the gums are uneven. If the cutting line is located close to the tooth root, the part of the appliance that covers the gums may cause pressure on the gums during the wearing process.

[0338] Therefore, the cutting line of the orthodontic appliance in this application is located in the gingival protrusion area within the adjustment range, so that when the user wears the orthodontic appliance generated by the cutting line, the orthodontic appliance will not compress the gums, thus improving comfort.

[0339] As can be seen from steps 1301 to 1302 above, by adjusting based on the initial cutting line, the orthodontic appliance cutting line is obtained, which makes the wrapping of the gingival area of ​​the orthodontic appliance cutting line higher than that of the initial cutting line. Therefore, when the user wears the orthodontic appliance generated by the orthodontic appliance cutting line, the wearing comfort can be improved.

[0340] In this embodiment of the invention, there are multiple ways to determine the orthodontic appliance cutting line based on the initial cutting line. It can be determined by moving the initial cutting line towards the gum line with a set step length. Alternatively, multiple cutting lines can be determined corresponding to each point of the initial cutting line, and then the orthodontic appliance cutting line can be generated based on the multiple cutting lines. Other methods can also be used to determine the orthodontic appliance cutting line, which are not limited here.

[0341] To facilitate understanding of this approach, the following describes how the initial cutting line is determined by moving the appliance cutting line in a set step towards the gum line.

[0342] In one possible scenario, since the initial cutting line does not provide strong coverage of the gingiva, the coverage of the appliance cutting line can be improved by considering the distance from the initial cutting line when generating the appliance cutting line. Specifically, based on the distance adjustment range indicated by the adjustment information of the initial cutting line, multiple candidate points on the tooth and model are determined for any initial point in the initial cutting line. The candidate point with the largest distance from the initial point is taken as the cutting point corresponding to that initial point. The angle appliance cutting line is then generated based on the cutting points corresponding to each initial point of the initial cutting line.

[0343] Because the surface of the gums is not smooth and regular, using only the maximum displacement of the initial incision line as the basis for determining the incision line of the orthodontic appliance will result in the incision line being placed too close to the root area. Appliances created in this way are prone to compressing the gums during daily wear and removal, causing discomfort to the patient. Long-term compression may also lead to gum redness, swelling, and pain, affecting the orthodontic experience and oral health.

[0344] Therefore, this approach considers generating the appliance cutting lines based on the curvature of the gingival region where the cutting point is located. Specifically, based on any initial point in the initial cutting line, multiple candidate points are determined on the dental model, all of which are located in the gingival region. The candidate point with the highest curvature is selected as the cutting point based on the curvature of the gingival region where each candidate point is located. Then, the appliance cutting lines are generated based on the cutting points corresponding to the initial points of the initial cutting line.

[0345] Because of the unique morphological characteristics of the gum surface—a convex structure near the crown and a flatter shape near the root—if the cutting line of the orthodontic appliance is set solely based on the curvature of alternative points, the degree of coverage of the teeth will be reduced compared to using only a fixed cutting line based on distance. This reduced coverage may lead to insufficient fit of the appliance during use, thereby affecting the precise transmission of corrective forces and the corrective effect, increasing the risk of appliance displacement, and reducing wearing stability and comfort.

[0346] The following describes an orthodontic appliance cutting line determined by distance and curvature, wherein at least one cutting point in the orthodontic appliance cutting line is determined by distance and curvature, where the distance is the distance between the cutting point and the initial point corresponding to the initial cutting line, and the curvature is the degree of curvature of the gingival region where the cutting point is located.

[0347] Figure 18 shows a flowchart of a method for determining the cutting line of an orthodontic appliance according to an embodiment of the present invention. The method includes the following steps:

[0348] Step 1801: Based on the distance adjustment range indicated by the adjustment information of the initial cutting line, determine multiple alternative points on the dental model for any initial point in the initial cutting line.

[0349] In this embodiment of the invention, for at least one initial point in the initial cutting line, based on the distance adjustment range indicated by the adjustment information of the initial cutting line, sampling is performed on the dental model along the normal direction towards the gingiva from the initial point within the distance adjustment range to obtain multiple candidate points of the initial point on the dental model, as shown in Figure 19.

[0350] Step 1802: Based on the distance between each candidate point and the initial point, and the curvature of the gingival region where each candidate point is located, select the cutting point corresponding to the initial point from multiple candidate points.

[0351] In this embodiment of the invention, for any candidate point, comprehensive information about the candidate point is determined based on the distance between the candidate point and the cutting point, and the curvature of the region where the candidate point is located on the dental model. Candidate points whose comprehensive information meets preset requirements are then designated as the cutting points corresponding to the cutting points. When determining the comprehensive information of the candidate points, the weight of the distance to the candidate point is lower than the weight of the curvature of the region where the candidate point is located.

[0352] Step 1803: Generate the orthodontic cutting line based on the cutting points corresponding to the initial points of the initial cutting line.

[0353] In this embodiment of the invention, the cutting points are connected to obtain the orthodontic appliance cutting line, wherein the orthodontic appliance cutting line is the cutting line formed by each protruding point in the gingival region within the adjustment range, as shown in Figure 20. In Figure 20, the solid line near the crown is the initial cutting line, and the dotted line is the orthodontic appliance cutting line.

[0354] As can be seen from steps 1801 to 1803 above, by finding an orthodontic appliance that meets the curvature requirements within the distance adjustment range as the appliance cutting line, both distance and curvature requirements are considered during the generation of the appliance cutting line. This ensures that the braces generated by the appliance cutting line can achieve both strong coverage and avoid compressing the gums.

[0355] Optionally, the adjustment range includes a distance adjustment range for the anterior teeth region and a distance adjustment range for the posterior teeth region; wherein the distance adjustment range for the anterior teeth region is greater than the distance adjustment range for the posterior teeth region.

[0356] Optionally, the initial cutting line adjustment information is obtained by inputting it through the user interface. Specifically, the initial cutting line adjustment information is obtained by the user inputting the corresponding distance adjustment range through the user interface.

[0357] Optionally, after obtaining the appliance cutting lines, the method also includes: displaying a dental model with the appliance cutting lines on the user interface.

[0358] The following describes how the initial cutting line is determined by moving the appliance in a set step towards the gum line.

[0359] In one possible scenario, due to insufficient coverage of the gingiva by the initial incision line, adjustments are made by moving the initial incision line towards the gum line and using the line that meets the required distance from the initial incision line as the appliance incision line. Specifically, based on the distance adjustment range indicated by the initial incision line adjustment information, multiple adjustment incision lines are obtained by moving the initial incision line towards the gum line by a set step size. The adjustment incision line that meets the required distance from the initial incision line is then used as the appliance incision line. This results in the appliance incision line being closer to the tooth root than the initial incision line, thus providing better coverage of the gum line. For patients with shorter tooth crowns, the appliance generated by the appliance incision line can also better cover the patient's teeth, making the appliance more secure.

[0360] However, considering the unevenness of the gum area, the above method only takes into account the initial incision line movement distance. Determining the aligner incision line based on the maximum movement distance will result in the aligner incision line being located relatively close to the tooth root. This means that aligners created based on incision lines close to the tooth root will cause pressure on the gums during insertion and removal.

[0361] Therefore, in order to avoid the problem of gum compression caused by the braces generated based on the aligner cutting lines, when adjusting the initial cutting lines, the initial cutting lines are moved towards the gums, and the cutting lines that meet the requirements of the gum protrusion area between the initial cutting lines are used as the aligner cutting lines. This ensures that the aligner cutting lines are located in the gum protrusion area compared to the initial cutting lines, thus avoiding the problem of gum compression when the patient wears braces generated based on the aligner cutting lines.

[0362] However, considering that the unevenness of the gum area mainly consists of raised areas near the teeth and sunken areas near the tooth roots, the wrapping effect of the orthodontic appliance cutting line determined solely by the requirements of the raised gum area will be lower than that of the orthodontic appliance cutting line determined solely by the distance requirements.

[0363] Therefore, this scheme, based on the distance adjustment range indicated by the initial cutting line adjustment information, obtains multiple adjustment cutting lines by moving the initial cutting line towards the gum line with a set step size. The adjustment cutting line that meets the requirements of the gum protrusion area is used as the orthodontic appliance cutting line. In this way, by finding the orthodontic appliance that meets the requirements of the gum protrusion area within the distance adjustment range as the appliance cutting line, both distance requirements and gum protrusion requirements are considered. This ensures that the aligners generated by the appliance cutting line achieve both strong coverage and avoidance of gum compression. It should be noted that the weight of the gum protrusion requirement is greater than the weight of the distance adjustment range.

[0364] Figure 21 shows a schematic diagram of the structure of an orthodontic appliance provided in an embodiment of the present invention. The orthodontic appliance is shell-shaped and includes multiple cavities for accommodating teeth. When the orthodontic appliance is worn in the user's oral cavity, the edge line of the orthodontic appliance is located in the user's gingival protrusion area.

[0365] Optionally, the edge line of the appliance is located at each protruding point in the gingival region within the adjustment range; the adjustment range is derived from the adjustment instructions for the initial cutting line.

[0366] Optionally, the edge line of the orthodontic appliance is the appliance cutting line, wherein the appliance cutting line is determined by an initial cutting line based on a dental model; the initial cutting line is used to characterize the boundary between the crown and the gingiva; the appliance cutting line is obtained based on the adjustment information of the initial cutting line, wherein the appliance cutting line is located in the gingival protrusion area within the adjustment range.

[0367] In the field of clinical orthodontics, bracketless shell dental instruments are increasingly used for orthodontic treatment, typically requiring multiple shell instruments for each procedure. The fabrication of shell dental instruments involves reverse engineering a digital model based on the patient's intraoral tooth alignment. This digital model is then used to design orthodontic movements, creating a new digital design model. This design model is 3D printed, then thermo-pressed using a polymer composite material, and finally cut or trimmed according to the gingival margin of the digital model. Typically, the gingival margin of the digital model matches the gingival margin of teeth worldwide, resulting in a shell dental instrument that covers the teeth. Finally, the shell dental instrument is placed in the patient's mouth, allowing the designed tooth movement mechanism to contact and apply force to the teeth for orthodontic correction.

[0368] However, the cross-section of the neck of some teeth is smaller than that of the crown. Furthermore, shell-shaped dental instruments are manufactured using a thermoforming process from the incisal edge to the gingival line at the tooth neck. Therefore, when inserting or removing these shell-shaped instruments, which are cut or trimmed to fit along the gingival line, some teeth may have crowns that are too thick, making them difficult to insert or remove. Forcing them in or out may cause localized deformation of the instrument, which could interfere with normal orthodontic treatment. Additionally, for children undergoing orthodontic treatment, whose teeth are still developing, it is not advisable to wrap the crown too tightly with dental instruments, as this could affect their tooth growth and development.

[0369] Therefore, optimizing dental instruments, reducing the risk of deformation caused by forceful insertion and removal, and minimizing their impact on children's teeth are urgent technical issues that need to be addressed.

[0370] Based on this, this application also provides a dental instrument and a method, device, equipment, and medium for adjusting the cutting line. In this method, an area to be adjusted in the initial cutting line is determined using a digital tooth model; the initial cutting line corresponding to the area to be adjusted is adjusted towards the crown direction so that the adjusted cutting line and the outermost contour line of the crown region in the digital tooth model meet a preset requirement; the preset requirement is a wearing requirement or orthodontic requirement; the adjusted cutting line is used to obtain the dental instrument corresponding to the digital tooth model.

[0371] Figure 22 is a schematic diagram of a cutting line adjustment process provided by some embodiments of this application. As shown in Figure 1, the process includes:

[0372] S2201: Using a digital model of the teeth, determine the area to be adjusted in the initial cutting line.

[0373] The method in this application embodiment is applied to an electronic device, which may be a server, PC, or other such device.

[0374] Figure 23 is a schematic diagram of the placement and removal of a dental instrument according to some embodiments of this application. As shown in Figure 23, the dental instrument needs to pass through the outermost contour of the crown area during placement or removal. Figure 24 is a schematic diagram of a tooth and gingiva according to some embodiments of this application. As shown in Figure 24, the initial cutting line of the dental instrument is generally located at the gingival line that surrounds the neck area of ​​the tooth. To avoid difficulty in inserting and removing the dental instrument due to the crown area being too large compared to the neck area of ​​some teeth, to reduce the risk of deformation of the dental instrument caused by forceful removal, and to reduce the coverage of children's teeth, in this embodiment of the application, the initial cutting line can be adjusted as a whole towards the crown, making the dental instrument shorter, thereby reducing the risk of deformation of the dental instrument and reducing the coverage of children's teeth. Figure 25 is a schematic diagram of the overall adjustment of the cutting line according to some embodiments of this application. As shown in Figure 25, the initial cutting line can be adjusted as a whole towards the crown.

[0375] In order to more accurately adjust the area to be adjusted in the initial cutting line, in this embodiment of the application, the area to be adjusted in the initial cutting line can be determined by the gingival line and the outermost contour line of the crown region of each tooth in the digital tooth model.

[0376] Specifically, for example, by comparing the distance between the outermost contour line of the crown region and the gingival line of the neck region of any tooth in the digital tooth model, it can be determined whether the distance exceeds a preset threshold. If so, it means that the crown region of the tooth is too large and the neck region is too small. If the tooth is cut according to the initial cutting line, i.e. the gingival line corresponding to the tooth, it may be difficult to put on or take off dental instruments in the area where the tooth is located. Therefore, the area where the tooth is located can be determined as the area to be adjusted in the initial cutting line.

[0377] S2202: Adjust the initial cutting line corresponding to the area to be adjusted towards the crown direction so that the adjusted cutting line and the outermost contour line of the crown area in the digital tooth model meet the preset requirements; the preset requirements are wearing requirements or orthodontic requirements; the adjusted cutting line is used to obtain the dental instrument corresponding to the digital tooth model.

[0378] To more accurately adjust the initial cutting line, ensuring a certain level of coverage without being too strong and affecting tooth development or making removal difficult, only a portion of the initial cutting line corresponding to the area to be adjusted can be adjusted towards the crown. This ensures that the adjusted cutting line and the outermost contour of the crown region in the digital tooth model meet preset requirements. These preset requirements can be thresholds determined based on wearing or treatment requirements. For example, a threshold for the area difference between the surface containing the cutting line and the outermost contour, a threshold for the length difference between the cutting line and the outermost contour, or a threshold for the distance between the projection lines of the cutting line and the outermost contour in a preset direction. Figure 5 is a schematic diagram of a partial adjustment of the cutting line according to some embodiments of this application. As shown in Figure 26, a portion of the initial cutting line, i.e., the area to be adjusted, can be adjusted towards the crown.

[0379] The adjusted cutting lines can be used to cut or process dental instruments corresponding to digital tooth models. This can optimize the placement or removal of dental instruments, making them easier to remove or wear, reducing the risk of deformation caused by forceful removal and wear, and appropriately reducing the envelopment of teeth, which is beneficial to tooth growth and development.

[0380] In this embodiment, the area to be adjusted in the initial cutting line is determined by the crown and neck regions of the digital tooth model. The initial cutting line corresponding to the area to be adjusted is then adjusted towards the crown so that the adjusted cutting line and the outermost contour of the crown region meet the wearing or orthodontic requirements. The adjusted cutting line is used to obtain the dental instrument corresponding to the digital tooth model, thereby optimizing the placement or dislocation of the dental instrument, reducing the risk of deformation of the dental instrument caused by forceful insertion and removal, and appropriately reducing the envelopment of the tooth, which is beneficial to the growth and development of the tooth.

[0381] To more accurately determine the area to be adjusted within the initial cutting line, thereby enabling more precise adjustment of the initial cutting line, based on the above embodiments, in this embodiment, determining the area to be adjusted within the initial cutting line using a digital tooth model includes:

[0382] The initial cutting line and the outermost contour line are projected in a preset direction to obtain a first projection line and a second projection line; based on the first projection line and the second projection line, the area to be adjusted in the initial cutting line is determined.

[0383] To more accurately determine the area to be adjusted within the initial cutting line, the initial cutting line (i.e., the gingival line and the outermost contour line of the crown region in the digital tooth model) can be projected in a preset direction to obtain a first projection line corresponding to the initial cutting line and a second projection line corresponding to the outermost contour line. The preset direction can be the direction of removal or insertion of dental instruments, or a direction perpendicular to the jaw plane, etc.

[0384] In one possible implementation, the initial cutting line (gingival line) corresponding to a single tooth and the outermost contour line of the single tooth in the crown region can be projected in a preset direction to obtain a first projection line and a second projection line. Figure 27 is a schematic diagram of a first projection line and a second projection line corresponding to a single tooth provided by some embodiments of this application. As shown in Figure 27, A is the first projection line and B is the second projection line.

[0385] In another possible implementation, the initial cutting lines (gingival lines) corresponding to multiple teeth and the outermost contour lines of the multiple teeth in the crown region can be projected in a preset direction to obtain a first projection line and a second projection line. It should be noted that when projecting multiple teeth, after projecting the outermost contour lines of the multiple teeth in the crown region, the adjacent areas between the teeth need to be smoothed and merged to form a single contour line, i.e., the second projection line. Figure 28a is a schematic diagram of the actual projection of the outermost contour lines of multiple teeth in the crown region provided by some embodiments of this application. As shown in Figure 28a, there are overlapping areas at the adjacent areas between the multiple teeth. Figure 28b is a schematic diagram of the second projection line corresponding to multiple teeth provided by some embodiments of this application. As shown in Figure 28b, the adjacent areas between the multiple teeth need to be smoothed and merged to form a single contour line, i.e., the second projection line.

[0386] Based on the shape difference between the first and second projection lines, the difference between the initial cutting line and the outermost contour line can be compared more accurately and conveniently, thereby determining the area to be adjusted in the initial cutting line. Specifically, the area to be adjusted in the initial cutting line can be determined based on the length difference or spacing difference between the first and second projection lines, or the area difference between the surfaces containing the first and second projection lines.

[0387] In this embodiment, the initial cutting line and the outermost contour line of the crown region can be projected in a preset direction to obtain a first projection line and a second projection line; thus, based on the shape difference between the first projection line and the second projection line, the area to be adjusted in the initial cutting line can be determined more accurately.

[0388] To further improve the accuracy of determining the area to be adjusted, based on the above embodiments, in this embodiment, determining the area to be adjusted in the initial cutting line based on the first projection line and the second projection line includes:

[0389] The region between the first projection line and the second projection line that satisfies at least one of the following conditions is identified as the region to be adjusted in the initial cutting line; the at least one condition includes:

[0390] The distance between the first projection line and the second projection line in any region exceeds a first threshold.

[0391] The length difference between the first projection line and the second projection line in any region exceeds the second threshold.

[0392] The area difference between the first projection line and the second projection line in any region exceeds a third threshold.

[0393] To more accurately determine the area to be adjusted, the area in the initial cutting line can be defined as the region satisfying at least one condition of shape difference between the first projection line and the second projection line. This at least one condition includes, but is not limited to: the distance between the first projection line and the second projection line in any region exceeding a first threshold; the length difference between the first projection line and the second projection line in any region exceeding a second threshold; and the area difference between the first projection line and the second projection line in any region exceeding a third threshold.

[0394] Specifically, the first projection line and the second projection line can be the projection lines of the initial cutting line and the outermost contour line of the crown region corresponding to a single tooth, or they can be the projection lines of the initial cutting line and the outermost contour line of the crown region corresponding to multiple teeth. For example, as shown in Figure 27 above, the first projection line forms a projection shape A on the projection surface, and the second projection line forms a projection shape B on the projection surface. Let the distance between A and B be D. If D is greater than a preset first threshold, then the area corresponding to the single tooth in the cutting line can be determined as the area to be adjusted. The size of the first threshold can be freely set according to actual needs, and this application does not limit it. Preferably, the first threshold is 2mm.

[0395] Figure 29 is a schematic diagram of another first projection line and second projection line corresponding to a single tooth according to some embodiments of this application. As shown in Figure 29, the first projection line forms a projection shape A on the projection surface, and the second projection line forms a projection shape B on the projection surface. Let the length of A be L1, the length of B be L2, and the length difference L = L2 - L1. If L is greater than a preset second threshold, the area corresponding to the single tooth in the cutting line can be determined as the area to be adjusted. The size of the second threshold can be freely set according to actual needs, and this application does not limit it. Preferably, the size of the second threshold can be determined according to the length of the first projection line, for example, L > 1 / 3L1.

[0396] For example, if the area of ​​the first projection line corresponding to a single tooth is M1 and the area of ​​the second projection line is M2, and the area difference between M1 and M2 exceeds a preset third threshold, then the area corresponding to the single tooth in the cutting line can be determined as the area to be adjusted.

[0397] In one possible implementation, for the first and second projection lines corresponding to relatively regular teeth, only conditional judgments based on area difference or length difference can be performed. For the first and second projection lines corresponding to teeth with attachments, conditional judgments based on spacing are also required. If the corresponding conditions are met, the corresponding area of ​​that single tooth in the initial cutting line is determined as the area to be adjusted. This prevents large local differences in teeth with attachments from affecting the dislocation and positioning of dental instruments, while improving the efficiency of determining the area to be adjusted. In another possible implementation, conditional judgments based on spacing difference, length difference, and area difference can be performed on the first and second projection lines corresponding to each tooth in the digital tooth model. If the corresponding conditions are met, the corresponding area of ​​that single tooth in the initial cutting line is determined as the area to be adjusted, further improving the accuracy of the area to be adjusted.

[0398] In this embodiment of the application, the region between the first projection line and the second projection line that satisfies at least one condition is determined as the region to be adjusted in the initial cutting line; wherein at least one condition includes, but is not limited to, the distance between the first projection line and the second projection line in either region exceeding a first threshold, the length difference exceeding a second threshold, and the area difference exceeding a third threshold, so that the region to be adjusted can be determined more accurately from multiple conditions corresponding to the shape difference between the first projection line and the second projection line.

[0399] To further improve the accuracy of adjusting the cutting line, based on the above embodiments, in this embodiment, the area to be adjusted includes at least one tooth and / or the area between two adjacent teeth.

[0400] To further improve the accuracy of adjusting the cutting line, the area to be adjusted includes at least one tooth; that is, the area to be adjusted can be a single tooth, multiple teeth, or even the entire dentition. The area to be adjusted can also be the area between two adjacent teeth. Figure 30 is a schematic diagram of a first projection line and a second projection line corresponding to multiple teeth according to some embodiments of this application. As shown in Figure 30, shape A is the first projection line, and shape B is the second projection line. Among them, adjustment 1 is to adjust the initial cutting line (shown as the first projection line A in the figure) corresponding to the entire set of multiple teeth, that is, to determine the area where the multiple teeth are located as the area to be adjusted for the initial cutting line. Adjustment 2 is to adjust the initial cutting line (shown as the first projection line A in the figure) corresponding to the multiple teeth and the area between two adjacent teeth.

[0401] In this embodiment of the application, the area to be adjusted can be the initial cutting line area corresponding to at least one tooth, or it can be the initial cutting line area corresponding to two adjacent teeth. Based on the above-mentioned area to be adjusted, the initial cutting line can be adjusted more precisely.

[0402] To more accurately adjust the initial cutting line and improve the efficiency of the adjustment, based on the above embodiments, in this embodiment, the step of projecting the initial cutting line and the outermost contour line in a preset direction to obtain a first projection line and a second projection line includes:

[0403] Projecting the tooth regions corresponding to the initial cutting line and the outermost contour line in a preset direction respectively, to obtain the first projection line and the second projection line; or,

[0404] Projecting the anterior tooth region and the two posterior tooth regions corresponding to the initial cutting line and the outermost contour line respectively in a preset direction yields the first projection line and the second projection line; or,

[0405] The entire regions of the initial cutting line and the outermost contour line are projected in a preset direction to obtain the first projection line and the second projection line.

[0406] Figure 31 is a schematic diagram showing the positioning orientation of different teeth corresponding to a dental instrument provided in some embodiments of this application. As shown in Figure 31, different teeth correspond to different positioning orientations. In order to adjust the initial cutting line more accurately and comprehensively, in one possible implementation, the tooth regions corresponding to the initial cutting line and the outermost contour line can be projected in a preset direction to obtain a first projection line and a second projection line. The first projection line and the second projection line can be multiple sets of projection lines corresponding to each tooth, or they can be a set of projection lines obtained by smoothing the intersection area of ​​the projection lines corresponding to each tooth.

[0407] As shown in Figure 23 above, since the positioning directions of the teeth in the anterior region are relatively similar, and the positioning directions of the teeth in the posterior regions on both sides are also relatively similar, in another possible implementation, the anterior region and the posterior regions corresponding to the initial cutting line and the outermost contour line can be projected in a preset direction to obtain a first projection line and a second projection line. The first projection line and the second projection line can be three sets of projection lines corresponding to the anterior region and the posterior regions on both sides, or they can be a set of projection lines obtained by smoothing the intersection area of ​​the projection lines corresponding to the anterior region and the posterior regions on both sides.

[0408] To further improve projection efficiency, in another possible implementation, the entire area of ​​the initial cutting line and the outermost contour line can be projected in a preset direction to obtain the first projection line and the second projection line.

[0409] In this embodiment, the initial cutting line and the outermost contour line can be projected onto different tooth regions to obtain a first projection line and a second projection line. Specifically, projecting the tooth regions corresponding to the initial cutting line and the outermost contour line in a preset direction to obtain the first and second projection lines allows for more precise identification of the area to be adjusted. Projecting the anterior tooth region and the two posterior tooth regions corresponding to the initial cutting line and the outermost contour line in a preset direction to obtain the first and second projection lines improves projection efficiency, thereby increasing the efficiency of adjusting the initial cutting line. Projecting the entire area of ​​the initial cutting line and the outermost contour line in a preset direction to obtain the first and second projection lines further improves projection efficiency, thereby further increasing the efficiency of adjusting the initial cutting line.

[0410] To further improve the efficiency and accuracy of adjusting the initial cutting line, based on the above embodiments, in this application embodiment, the preset direction includes at least one of the following: the long axis direction of the tooth, the disengagement direction of the dental instrument corresponding to the tooth, the direction perpendicular to the occlusal plane, the direction perpendicular to the horizontal plane, the overall disengagement direction of the dental instrument, the direction perpendicular to the plane where the anterior tooth region is located, the overall disengagement direction of the anterior tooth region, the direction perpendicular to the planes where the two posterior tooth regions are located respectively, and the overall disengagement directions of the two posterior tooth regions respectively.

[0411] To further improve the efficiency and accuracy of adjusting the initial cutting line, the preset projection direction can include, but is not limited to, the long axis direction of each tooth and the detachment direction of the dental instrument corresponding to each tooth; as shown in Figure 31 above, there are slight differences in the detachment directions of different teeth. The preset direction can also be a direction perpendicular to the occlusal plane, a direction perpendicular to the horizontal plane, or the overall detachment direction of the dental instrument; or a direction perpendicular to the plane where the anterior tooth region is located, a direction perpendicular to the planes where the two posterior tooth regions are located respectively, the overall detachment direction of the anterior tooth region, or the overall detachment direction of the two posterior tooth regions respectively. As shown in Figure 23 above, there are slight differences in the detachment directions of the anterior tooth region and the posterior tooth region.

[0412] In one possible implementation, when the preset projection direction is the placement or dislocation direction of the dental instrument corresponding to each tooth, the projection direction is different for different teeth, the projection plane is perpendicular to the placement or dislocation direction, and a deviation within a preset threshold is allowed; Figure 32 is a schematic diagram of a projection plane and placement direction provided by some embodiments of this application. As shown in Figure 32, the projection plane is perpendicular to the placement or dislocation direction, and a deviation of ±10° is allowed.

[0413] It should be noted that the specific projection direction can be freely set according to actual needs, and this application does not limit it.

[0414] In the embodiments of this application, the preset projection direction may include, but is not limited to, the long axis direction of each tooth, the disengagement direction of the dental instrument corresponding to each tooth; the direction perpendicular to the occlusal plane, the direction perpendicular to the horizontal plane, the overall disengagement direction of the dental instrument; or the direction perpendicular to the plane where the anterior tooth region is located, the direction perpendicular to the planes where the two posterior tooth regions are located respectively, the overall disengagement direction of the anterior tooth region, and the overall disengagement direction of the two posterior tooth regions respectively, thereby further improving the efficiency and accuracy of adjusting the initial cutting line.

[0415] To more accurately adjust the initial cutting line, based on the above embodiments, in this embodiment, adjusting the initial cutting line corresponding to the area to be adjusted towards the crown direction so that the adjusted cutting line and the outermost contour line of the digital tooth model in the crown region meet preset requirements includes:

[0416] Adjust the initial cutting line corresponding to the area to be adjusted towards the crown direction until the adjusted cutting line and the outermost contour line of the digital tooth model in the crown region satisfy at least one of the following:

[0417] The distance between the first projection line and the second projection line in any region does not exceed a first threshold; and / or, the length difference between the first projection line and the second projection line in any region does not exceed a second threshold; and / or, the area difference between the first projection line and the second projection line in any region does not exceed a third threshold.

[0418] To more accurately adjust the initial cutting line, the initial cutting line corresponding to the area to be adjusted can be adjusted towards the crown direction by a preset step size until the adjusted cutting line and the outermost contour line of the digital tooth model in the crown area meet at least one of the following conditions: the distance between the first projection line of the adjusted cutting line in the preset direction and the second projection line of the outermost contour line in the preset direction in any area does not exceed a first threshold; and / or, the length difference between the first projection line and the second projection line in any area does not exceed a second threshold; and / or, the area difference between the first projection line and the second projection line in any area does not exceed a third threshold.

[0419] Specifically, as shown in Figure 25 above, the cutting line can be adjusted upwards as a whole; or as shown in Figure 26 above, a local part of the cutting line, i.e. the area to be adjusted, can be adjusted upwards until the adjusted first projection line and second projection line meet at least one of the above conditions.

[0420] In this embodiment, the initial cutting line corresponding to the area to be adjusted is adjusted towards the crown direction until the adjusted cutting line and the outermost contour line of the digital tooth model in the crown region satisfy at least one of the following: the distance between the first projection line and the second projection line in any region does not exceed a first threshold; and / or, the length difference between the first projection line and the second projection line in any region does not exceed a second threshold; and / or, the area difference between the first projection line and the second projection line in any region does not exceed a third threshold; thereby ensuring that the dental instrument obtained based on the adjusted cutting line meets the wearing or orthodontic requirements.

[0421] In order to more accurately adjust the initial cutting line, based on the above embodiments, in the embodiments of this application, the first threshold, the second threshold and the third threshold are all determined according to at least one of the following conditions: the material of the dental instrument in any region, the thickness of the dental instrument in any region, the position of the tooth in any region, and the developmental state of the tooth in any region.

[0422] The first, second, and third thresholds are all influenced by numerous factors. Verification tests show that the first, second, and third thresholds are all negatively correlated with the elastic modulus of the dental instrument's material in any given region. The harder the material, the less prone it is to deformation, and the first, second, and third thresholds all need to be appropriately reduced.

[0423] The first, second, and third thresholds are all related to the thickness of the dental instrument in any region. The greater the thickness, the less likely it is to deform. The first, second, and third thresholds should all be appropriately reduced.

[0424] The first, second, and third thresholds are all related to the position of the teeth within any region, with the thresholds for posterior teeth being smaller than those for anterior teeth.

[0425] The first, second, and third thresholds are all related to the developmental state of teeth within any given region. Teeth still developing should not have too much occlusal force, and their corresponding thresholds are smaller compared to teeth that have completed development. The cutting line can be adjusted to make dental instruments shorter, resulting in less encapsulation of the teeth and reducing the impact on children's tooth growth and development. Therefore, a smaller threshold is needed for detection and adjustment compared to adults.

[0426] In this embodiment of the application, a first threshold, a second threshold, and a third threshold can be determined based on the material of the dental instrument in any region, the thickness of the dental instrument in any region, the position of the teeth in any region, and the developmental state of the teeth in any region, thereby enabling more accurate adjustment of the cutting line.

[0427] To more accurately adjust the initial cutting line and improve the efficiency of the adjustment, based on the above embodiments, in this embodiment, before determining the area to be adjusted in the initial cutting line, the following steps are further included:

[0428] The gingival line and the outermost contour line of the crown region of each tooth in the digital tooth model are projected in a preset direction to obtain the third projection line and the fourth projection line; it is determined that the third projection line and the fourth projection line of at least one tooth meet the adjustment requirements of the initial cutting line.

[0429] To improve the efficiency of adjusting the initial cutting line, before determining the area to be adjusted within the initial cutting line, the gingival line and the outermost contour of the crown region of each tooth in the digital tooth model can be projected in a preset direction to obtain a third projection line and a fourth projection line. If the difference in spacing, length, or area between the third and fourth projection lines meets the corresponding threshold, it can be determined that the third and fourth projection lines of the tooth meet the adjustment requirements of the initial cutting line, and the subsequent step of determining the area to be adjusted within the initial cutting line can proceed. If the difference in spacing, length, or area between the third and fourth projection lines does not meet the corresponding threshold, it is indicated that the third and fourth projection lines of the tooth do not meet the adjustment requirements of the initial cutting line, and the subsequent step of determining the area to be adjusted within the initial cutting line is not required.

[0430] In this embodiment of the application, before determining the area to be adjusted in the initial cutting line, the gingival line and the outermost contour line of the crown region of each tooth in the digital tooth model can be projected in a preset direction to obtain a third projection line and a fourth projection line. After determining that the third projection line and the fourth projection line of at least one tooth meet the adjustment requirements of the initial cutting line, the subsequent step of determining the area to be adjusted in the initial cutting line is performed, so as to adjust the initial cutting line more accurately and improve the efficiency of adjusting the initial cutting line.

[0431] Based on the same technical concept, and on the basis of the above embodiments, this application provides a dental instrument, which has a shell-like structure.

[0432] The outline of the opening of the shell-like structure and the outermost outline of the dental instrument in the crown area meet preset requirements; the preset requirements are to meet the wearing requirements or orthodontic requirements of the dental instrument; the opening of the shell-like structure is obtained by cutting lines and the corresponding digital model of the teeth of the dental instrument.

[0433] Specifically, Figure 25 above shows a dental instrument with overall adjusted cutting lines. Figure 26 above also shows a dental instrument with partially adjusted cutting lines. The outline of the opening of the dental instrument in this embodiment is obtained based on the adjusted cutting lines.

[0434] In one possible implementation, the opening contour line and the outermost contour line satisfy a preset requirement by using a first projection line of the opening contour line in a preset direction and a second projection line of the outermost contour line in a preset direction.

[0435] The opening contour line and the outermost contour line meet the requirements. They can be obtained by directly measuring the opening contour line and the outermost contour line, or they can be obtained by the projection of the opening contour line and the outermost contour line in a preset direction, namely the first projection line and the second projection line.

[0436] In one possible implementation, the preset requirement is that the distance between the first projection line and the second projection line in any region does not exceed a first threshold; and / or, the length difference between the first projection line and the second projection line in any region does not exceed a second threshold; and / or, the area difference between the first projection line and the second projection line in any region does not exceed a third threshold.

[0437] In one possible implementation, the preset direction includes at least one of the following: the long axis direction of the tooth, the disengagement direction of the dental instrument corresponding to the tooth, the direction perpendicular to the occlusal plane, the direction perpendicular to the horizontal plane, the overall disengagement direction of the dental instrument, the plane where the anterior tooth region is located, the overall disengagement direction of the anterior tooth region, the planes where the two posterior tooth regions are located respectively, and the overall disengagement directions of the two posterior tooth regions respectively.

[0438] In one possible implementation, the first threshold, the second threshold, and the third threshold are all determined based on at least one of the following conditions: the material of the dental instrument in any region, the thickness of the dental instrument in any region, the position of the teeth in any region, and the developmental state of the teeth in any region.

[0439] During orthodontic treatment, braces are typically worn for treatment or retention. Currently, in the manufacturing process of braces, the edge lines are often designed using a standardized method, with the gingival margin of the user's teeth serving as the edge line. This results in braces that fit snugly against the patient's gums. However, because different users have different tooth shapes, using the gingival margin as the edge line can make it difficult for some users to remove or put on their braces.

[0440] For different users, the design of orthodontic appliances needs to be tailored to their specific dental conditions to ensure effective treatment. Currently, the edge line of the appliance is based on the gingival margin of the user's teeth, as shown in Figure 33. This results in the appliance fitting snugly against the gums when worn. However, due to differences in tooth morphology, using the gingival margin as the appliance's edge line can make it difficult for some users to remove the appliances.

[0441] In view of this, this application provides an edge line generation method to generate a reasonable orthodontic edge line, so that the orthodontic appliance with the generated edge line as the edge shape can maintain sufficient wrapping force and force while being easy for the user to put on and take off.

[0442] Figure 34 is a schematic flowchart of an edge line generation method provided in an embodiment of this application. This edge line generation method can be executed by an electronic device or a component inside the electronic device. For ease of description, the following embodiments use execution by an electronic device as an example. As shown in Figure 34, the edge line generation method includes the following steps:

[0443] Step 3401: The electronic device acquires the user's digital dental model.

[0444] In some embodiments, three-dimensional data of a user's teeth can be obtained by performing oral scanning on the patient using an oral scanning device, computed tomography (CT) scanning technology, etc. Then, an electronic device can acquire the three-dimensional data of the user's teeth and generate a digital dental model of the user based on the three-dimensional data of the user's teeth.

[0445] It should be understood that the edge line generation method provided in this application embodiment can be applied to the manufacturing of orthodontic appliances at any stage of the entire orthodontic process of the user's teeth. The digital dental model in step 3401 above can be a three-dimensional dental model corresponding to the initial position of the user's teeth, or it can be a three-dimensional dental model corresponding to the user's teeth at any stage of orthodontic treatment.

[0446] Step 3402: The electronic device determines the difficulty of removing and inserting the orthodontic appliance based on the user's tooth feature data extracted from the digital dental model, with the user's gingival margin as the target appliance edge line; the tooth feature data is used to characterize the morphological features of the user's teeth.

[0447] In step 3402 above, the difficulty of removing and inserting the orthodontic appliance can be understood as the difficulty of removing and inserting the target orthodontic appliance made with the user's gingival margin as the edge line of the target appliance onto the user's teeth.

[0448] Electronic devices can extract a user’s tooth feature data based on a digital dental model, which includes one or more parameter items.

[0449] In one possible implementation, the tooth characteristic data includes at least one of the following: crown height; undercut depth; crowding; rotation; buccal-lingual tilt; and arch morphology.

[0450] The crown height is the distance from the occlusal surface or incisal edge of the tooth to the gingival margin, which is the outline of the junction between the tooth and the gingiva. The crown height of different teeth of the same user may be the same or different.

[0451] The process of extracting the crown height of a user's teeth based on a digital dental model is described below. First, key markers for each tooth in the digital dental model are identified, including the most prominent point on the occlusal surface or incisal edge, and the gingival margin. Then, for each tooth, the vertical distance from the most prominent point to the gingival margin contour line is calculated; this distance is the crown height of the tooth. This application does not limit the specific numerical value of the crown height for different teeth. Table 1 below exemplarily shows the crown height and tooth characteristics corresponding to different tooth types.

[0452] Table 1

[0453] Table 1 lists the normal range values ​​for the crown height of the maxillary central incisors, maxillary lateral incisors, mandibular central incisors, first premolars, and first molars. These normal range values ​​can be determined based on clinical experience. Since orthodontic appliances are manufactured based on a digital dental model of the user's teeth, the appliances fit the user's teeth closely. The crown height of the user's teeth affects the ease of removing and inserting the appliances; the larger the crown height, the more difficult it is to remove and insert the appliances, and vice versa. By considering the impact of tooth height on the ease of removal and insertion when generating the appliance's edge line, a reasonable edge line can be generated. This ensures that the target appliance, with the generated edge line as its boundary shape, maintains sufficient containment and force while being easy for the user to remove and insert, minimizing difficulties caused by crown height.

[0454] Tooth undercuts include natural depressions on the axial surface of the crown, root depressions exposed after gum recession, and triangular gaps formed below the contact points of adjacent teeth. Generally, tooth tilting or twisting can also create undercuts.

[0455] The following describes the process of extracting the undercut depth of a user's teeth based on a digital dental model. Taking a single tooth as an example, as shown in Figure 35 (undercut diagram), firstly, observation lines are generated on the digital dental model. These observation lines, also known as guide lines, are lines drawn by the tracing lead of the model observer along the axial surface of the tooth crown and the most prominent points of the soft and hard tissues. Then, the concave area on the gingival side of the observation line, i.e., the undercut area, is identified, and the vertical distance from the deepest point of the concave area to the observation line is measured, which is the undercut depth. If the tooth is tilted or twisted, additional undercuts caused by abnormal posture are simultaneously identified and included in the comprehensive calculation of the undercut depth. In this embodiment, the undercut depth of each tooth with undercuts on the digital dental model is extracted.

[0456] The presence of undercuts on teeth increases the difficulty of removing and inserting orthodontic appliances. The greater the undercut depth, the more difficult it is to remove and insert the appliance; conversely, the smaller the undercut depth, the easier it is. This application's embodiments extract the undercut depth of the user's teeth and consider the impact of undercut depth on the ease of appliance removal and insertion when generating the appliance's edge line. This aims to minimize difficulties in appliance removal and insertion caused by undercut depth when generating the appliance's edge line.

[0457] Tooth crowding is used to characterize the degree of crowding in a user's teeth. The following describes the process of extracting a user's tooth crowding based on a digital dental arch model. For example, firstly, the user's dental arch contour and the width of each tooth in the mesiodistal direction are extracted from the digital dental arch model, and the length of the dental arch contour is determined. The first difference between the sum of the widths of all teeth in the maxilla and the length of the maxillary dental arch contour is calculated. The larger this first difference, the higher the crowding of the maxillary teeth; the smaller the first difference, the lower the crowding of the maxillary teeth. Similarly, the second difference between the sum of the widths of all teeth in the mandible and the length of the mandibular dental arch contour can be calculated. The larger this second difference, the higher the crowding of the mandibular teeth; the smaller the second difference, the lower the crowding of the mandibular teeth.

[0458] For the same orthodontic appliance, the higher the degree of tooth crowding, the more difficult it is to insert and remove the appliance. This application's embodiments extract the degree of tooth crowding from the user's teeth and consider the impact of tooth crowding on the ease of appliance insertion and removal when generating the appliance's edge line. This allows for the generation of an appliance edge line that reduces the difficulty of appliance insertion and removal based on tooth crowding, thereby minimizing the problem of difficulty in appliance insertion and removal caused by high tooth crowding when generating the appliance edge line.

[0459] Tooth rotation is a measure of the degree of tooth twisting. It can be represented by the angle between the actual long axis and the ideal long axis of the tooth; the larger the angle, the greater the degree of tooth twisting. The ideal long axis of the tooth is the ideal central axis from the crown tip to the root tip, which can be determined by referring to the physiological posture of a normal tooth.

[0460] The degree of tooth rotation also affects the ease of removing and inserting orthodontic appliances. The greater the tooth rotation, the more difficult it is to remove and insert the appliance; conversely, the smaller the tooth rotation, the easier it is. In this embodiment, the degree of tooth rotation for each tooth of the user is extracted based on a digital dental model. By considering the impact of tooth rotation on the ease of removing and inserting the appliance when generating the appliance's edge line, the problem of difficulty in removing and inserting the appliance due to large tooth rotation is minimized during the generation of the appliance's edge line.

[0461] The buccal-lingual inclination is used to characterize the degree to which a tooth tilts towards the buccal or lingual side. If a tooth tilts towards the lingual side, the buccal-lingual inclination is used to characterize the degree of tilt towards the lingual side; if a tooth tilts towards the buccal side, the buccal-lingual inclination is used to characterize the degree of tilt towards the buccal side. The degree of buccal-lingual inclination can be represented by the angle between the long axis of the tooth and the coronal plane of the dental arch. The larger the angle, the greater the degree of tilt; the smaller the angle, the smaller the degree of tilt.

[0462] In this embodiment, the coronal plane of the dental arch in the digital dental model can be determined first. The coronal plane is a plane perpendicular to the trajectory of the dental arch. Then, the angle between the long axis of each tooth and the coronal plane of the dental arch is determined. In this embodiment, the buccal-lingual inclination of each tooth of the user is extracted based on the digital dental model. By considering the influence of the buccal-lingual inclination on the ease of wearing and removing the aligner when generating the aligner edge line, the problem of difficulty in wearing and removing the aligner due to a high degree of buccal-lingual inclination can be avoided as much as possible when generating the aligner edge line.

[0463] The shape of the dental arch also affects the ease of wearing and removing orthodontic appliances. The dental arch is an arch-shaped structure formed by the continuous arrangement of the maxillary and mandibular teeth on the alveolar bone. It mainly includes the upper dental arch and the lower dental arch. The normal shape of the dental arch is mainly square, oval, and pointed.

[0464] In this embodiment, the dental arch contour lines of the user's maxilla and mandible are extracted based on the user's digital dental model. Taking the maxillary dental arch contour line as an example, the morphology of the maxillary dental arch can be represented by the quantitative value of the difference between the user's maxillary dental arch contour line extracted based on the digital dental model and the ideal maxillary contour line. For example, the quantitative value can be the distance between a series of coordinate points on the two contour lines. The larger the distance, the greater the difficulty of removing and inserting the corresponding orthodontic appliance; the smaller the quantitative value, the easier it is to remove and insert the corresponding orthodontic appliance. The quantitative value corresponding to the mandibular dental arch shape can be referred to the relevant description of the maxillary dental arch shape, which will not be repeated here. For example, the dental arch contour line comparison diagram shown in Figure 36 shows that (a) in Figure 36 is the user's mandibular dental arch contour line, and (b) in Figure 36 is the user's ideal mandibular contour line. Since some coordinate points on the user's dental arch contour line deviate significantly from the ideal contour line, it increases the difficulty of removing and inserting the orthodontic appliance. In this embodiment of the application, by considering the influence of the dental arch shape on the ease of removing and inserting the orthodontic appliance when generating the edge line of the appliance, the problem of difficulty in removing and inserting the appliance caused by the dental arch shape deviating from the ideal dental arch shape can be avoided as much as possible when generating the edge line of the appliance.

[0465] Since orthodontic appliances are made based on the user's digital dental model, the outline of the appliance is in close contact with the outline of the user's teeth. When there are undercuts on the user's teeth, it increases the difficulty of removing and putting on the appliance. To reduce the difficulty of removing and putting on the appliance, the digital dental model can be filled with undercuts, and then the appliance can be made based on the digital dental model after the undercuts are filled. In this way, the appliance will no longer be in close contact with the undercuts on the user's teeth, thus preventing the difficulty of removing and putting on the appliance due to the presence of undercuts.

[0466] In one possible implementation, the tooth feature data also includes the degree of undercut filling in the interdental spaces. After step 3401 above, i.e., after acquiring the user's digital dental model, the electronic device further includes filling the interdental undercuts in the digital dental model; then, the degree of interdental undercut filling is determined based on the filling status. A higher degree of interdental undercut filling makes appliance insertion and removal easier, while a lower degree of filling makes appliance insertion and removal more difficult. In this embodiment, the degree of interdental undercut filling is extracted based on the user's digital dental model. By considering the influence of the degree of interdental undercut filling on the ease of appliance insertion and removal when generating the appliance edge line, the difficulty of appliance insertion and removal due to the presence of interdental undercuts is minimized when generating the appliance edge line.

[0467] In one possible implementation, for a target tooth in a digital dental model, the parameter values ​​corresponding to the tooth feature data of the target tooth are compared with the threshold values ​​corresponding to the tooth feature data to determine the difficulty of appliance insertion and removal in the area where the target tooth is located; the target tooth is any tooth in the digital dental model, and the threshold values ​​corresponding to the tooth feature data can be one or more values ​​or one or more value ranges, which is not limited in this application.

[0468] For example, the difficulty of removing and putting on orthodontic appliances is divided into different difficulty levels: high, medium and low. Different difficulty levels correspond to different thresholds for tooth characteristic data.

[0469] Taking the maxillary central incisor as the target tooth and crown height as an example, the difficulty of removing and inserting the orthodontic appliance in the target tooth area is explained. The threshold corresponding to crown height can be determined based on the normal range of crown height values ​​in Table 1 above. Taking the maxillary central incisor as the target tooth, the threshold corresponding to crown height includes two values: the maximum value of the normal range of crown height, i.e., 12.5mm; and 1.2 times the maximum value of the normal range of crown height, i.e., 12.5mm * 1.2 = 15mm. If the parameter value corresponding to the user's crown height is less than the maximum value of the normal range of crown height, i.e., 12.5mm, the difficulty of removing and inserting the appliance is determined to be low. If the user's crown height is greater than 1.2 times the maximum value of the normal range, i.e., 15mm, the difficulty of removing and inserting the appliance is determined to be high. If the parameter value corresponding to the user's crown height is greater than the maximum value of the normal range but less than 1.2 times the maximum value of the normal range, i.e., greater than 12.5mm but less than 15mm, the difficulty of removing and inserting the appliance is determined to be medium.

[0470] For example, the difficulty of removing and inserting orthodontic appliances can be divided into multiple difficulty levels, such as levels 1 to 4. Different difficulty levels correspond to different thresholds (or threshold ranges) in the tooth feature data. By comparing the parameter values ​​corresponding to the target tooth feature data with the corresponding thresholds, the difficulty level of the target tooth region is determined. For example, if the user's crown height is 0-12.5mm, the difficulty level is level 1; if the user's crown height is 12.5-13.5mm, the difficulty level is level 1; if the user's crown height is 13.5-14.5mm, the difficulty level is level 3; and if the user's crown height is above 14.5mm, the difficulty level is level 4.

[0471] Step 3403: Adjust the edge line of the target orthodontic appliance according to the difficulty of removing and wearing the appliance to obtain the first edge line of the orthodontic appliance; the first edge line of the orthodontic appliance is used to generate the edge shape of the target orthodontic appliance corresponding to the digital tooth model, or the first edge line of the orthodontic appliance is the edge shape of the target orthodontic appliance.

[0472] In one possible implementation, the edge line of the target orthodontic appliance is adjusted to obtain the first edge line of the orthodontic appliance based on the difficulty of removing and inserting the appliance and the edge adjustment strategy; the edge adjustment strategy includes the adjustment range of the edge line of the orthodontic appliance towards the crown direction being positively correlated with the difficulty of removing and inserting the appliance.

[0473] For example, based on the difficulty of removing and wearing the aligner and the edge adjustment strategy, the reference edge line is adjusted to obtain the first aligner edge line, where the reference edge line can be the gingival margin of the user's teeth. Taking the difficulty of removing and wearing the aligner as divided into high, medium, and low difficulty as an example, different difficulty levels correspond to different adjustment ranges. For example, the adjustment range corresponding to low difficulty is 0. If the difficulty of removing and wearing the aligner is low, the gingival margin is used as the aligner edge line, and no adjustment is made. The adjustment range for medium difficulty is 1mm. If the difficulty of removing and wearing the aligner is medium, the gingival margin is adjusted 1mm towards the crown. The adjustment range for high difficulty is 2mm. If the difficulty of removing and wearing the aligner is high, the gingival margin is adjusted 2mm towards the crown.

[0474] In some embodiments, the edge adjustment strategy includes at least one of the following: the tooth's removal / adoption zone; tooth number; removal / adoption order; removal / adoption priority; and removal / adoption location. The removal / adoption zone may include, for example, the anterior tooth zone, posterior tooth zone, lingual side, and labial side.

[0475] In one possible implementation, the first orthodontic edge line is obtained by adjusting the edge line of the target orthodontic appliance according to the difficulty of removing and wearing the appliance and the edge adjustment strategy. This can be achieved by adjusting the edge line of the target orthodontic appliance corresponding to the target tooth towards the crown direction, based on the fact that the difficulty of removing and wearing the appliance in the area where the target tooth is located is greater than the expected difficulty of removal and wearing.

[0476] The expected difficulty of appliance removal and insertion can be the difficulty of appliance removal and insertion corresponding to the normal parameter values ​​of tooth characteristic data, such as the normal parameter values ​​of tooth height as shown in Table 1. If the difficulty of appliance removal and insertion in the target tooth area is less than or equal to the expected difficulty of appliance removal and insertion, the gingival margin of the target tooth is used as the corresponding orthodontic edge line.

[0477] In some embodiments, the difficulty of removing and inserting the orthodontic appliance in the target tooth area compared with the expected removal and insertion difficulty can be determined by judging the relationship between the parameter values ​​of each parameter item included in the tooth feature data and the threshold values ​​corresponding to the parameter items. For any parameter in the tooth feature data, if the value corresponding to the parameter of the target tooth is less than or equal to the threshold value corresponding to the parameter, then the difficulty of removing and inserting the orthodontic appliance in the target tooth area is less than or equal to the expected removal and insertion difficulty, and the edge line of the orthodontic appliance corresponding to the target tooth is the gingival margin line corresponding to the target tooth; if the value corresponding to the parameter of the target tooth is greater than the threshold value corresponding to the parameter, then the difficulty of removing and inserting the orthodontic appliance in the target tooth area is greater than the expected removal and insertion difficulty, and the edge line of the orthodontic appliance corresponding to the target tooth can be adjusted from the gingival margin line corresponding to the target tooth towards the crown direction.

[0478] Taking crown height as an example of a parameter included in tooth feature data, if the parameter value of the crown height of the target tooth is less than or equal to the first threshold, then the edge line of the orthodontic appliance corresponding to the target tooth is the gingival margin line corresponding to the target tooth; if the parameter value of the crown height of the target tooth is greater than the first threshold, the edge line of the orthodontic appliance corresponding to the target tooth is adjusted from the gingival margin line corresponding to this tooth towards the crown.

[0479] Taking the dental arch morphology as an example, if the distance between the dental arch contour line corresponding to the target tooth and the reference contour line corresponding to the target tooth is less than or equal to the second threshold, then the difficulty of removing and wearing the orthodontic appliance in the area where the target tooth is located is less than or equal to the expected removal and wearing difficulty, and the edge line of the orthodontic appliance corresponding to the target tooth is set as the gingival margin line corresponding to the target tooth; if the distance between the dental arch contour line corresponding to the target tooth and the reference contour line corresponding to the target tooth is greater than the second threshold, then the difficulty of removing and wearing the orthodontic appliance in the area where the target tooth is located is greater than the expected removal and wearing difficulty, and the edge line of the orthodontic appliance corresponding to the target tooth can be adjusted from the gingival margin line corresponding to this tooth towards the crown.

[0480] The embodiments of this application are applicable to different orthodontic appliance manufacturing methods, such as diaphragm pressing to obtain orthodontic appliances, or 3D printing to obtain orthodontic appliances. The embodiments of this application do not limit the manufacturing method of orthodontic appliances.

[0481] In one possible implementation, in the method of obtaining an orthodontic appliance by pressing a solid dental model with a diaphragm, the edge line of the first orthodontic appliance is used to generate the edge shape of the target orthodontic appliance corresponding to the digital dental model. For example, after obtaining the orthodontic appliance to be cut by pressing with a diaphragm, the edge of the orthodontic appliance to be cut is cut according to the edge line of the first orthodontic appliance to obtain the target orthodontic appliance.

[0482] In another possible implementation, the orthodontic appliance is manufactured by 3D printing, for example, using resin material. Based on at least one of the user's dental feature data and the performance data of the resin material used to manufacture the user's orthodontic appliance, a target orthodontic appliance corresponding to the digital dental model is generated, that is, the first edge line of the orthodontic appliance in step 203 above is the edge shape of the target orthodontic appliance.

[0483] In this embodiment, the difficulty of removing and wearing the orthodontic appliance is determined by extracting tooth feature data based on the user's digital dental model, with the user's gingival margin as the edge line of the target appliance. Then, the edge line of the target appliance is adjusted based on the determined difficulty of removing and wearing the appliance, thereby obtaining a reasonable first edge line of the appliance. This helps to realize the personalized manufacturing of the appliance, and allows the target appliance with the first edge line as the edge shape to maintain sufficient wrapping force and force while being easy for the user to remove and wear.

[0484] In some embodiments, the electronic device determines the first orthodontic appliance edge line based on at least one of the user's dental feature data and the performance data of the materials used to manufacture the user's orthodontic appliance. Specifically, this can be divided into three cases: Case 1, the electronic device generates the first orthodontic appliance edge line corresponding to the digital dental model based on the user's dental feature data. Case 2, the electronic device generates the first orthodontic appliance edge line corresponding to the digital dental model based on the performance data of the materials used to manufacture the user's orthodontic appliance. Case 3, the electronic device generates the first orthodontic appliance edge line corresponding to the digital dental model based on the user's dental feature data and the performance data of the materials used to manufacture the user's orthodontic appliance.

[0485] The performance data of the materials used to manufacture user orthodontic appliances include at least one of the following: material thickness, material elastic modulus, and material bending stiffness.

[0486] The bending stiffness D of a material can be calculated using the following formula:

[0487] Where E is the elastic modulus, t is the material thickness, and v is Poisson's ratio, for example, the Poisson's ratio of TPU is 0.4.

[0488] In some embodiments, the electronic device may also establish a first mapping relationship, which includes the relationship between at least one of preset tooth feature data and material performance data and a preset edge line; the determination of the first orthodontic appliance edge line based on the user's tooth feature data and at least one of the performance data of the material used to manufacture the user's orthodontic appliance may be achieved by generating the first orthodontic appliance edge line based on the user's tooth feature data and at least one of the performance data of the material used to manufacture the user's orthodontic appliance, and the first mapping relationship.

[0489] For example, the first mapping relationship can be established based on multiple sets of sample data. These multiple sets of sample data can be obtained based on mechanical stress simulation, big data, clinical trial feedback, or physical experiments. Each set of sample data includes at least one of the preset tooth feature data and preset material performance data, as well as a preset edge line.

[0490] In other embodiments, the electronic device further establishes a first mapping relationship, which includes the relationship between at least one of preset tooth feature data and preset material performance data and the coordinates of multiple control points corresponding to the preset edge line. The determination of the first orthodontic appliance edge line based on the user's tooth feature data and at least one of the performance data of the material used to manufacture the user's orthodontic appliance can be achieved in the following manner: the electronic device generates the first orthodontic appliance edge line based on the user's tooth feature data, at least one of the performance data of the material used to manufacture the user's orthodontic appliance, and the first mapping relationship.

[0491] In some embodiments of this application, the first mapping relationship can be established by multiple sets of sample data. The multiple sets of sample data can be obtained based on mechanical stress simulation, big data, clinical trial feedback, or physical experiments. Each set of sample data includes at least one of the preset tooth feature data and preset material performance data, as well as the coordinates of multiple control points corresponding to the preset edge line.

[0492] For example, shell-shaped dental instruments (or shell-shaped instruments with a rigidity greater than 50.0 N·mm) are made by pressing a material with a thickness of 0.8–1.2 mm and an elastic modulus of 1500–2000 MPa. 2 When the crown height of the user's posterior teeth is greater than 8 mm and the undercut depth is greater than 0.5 mm, the control points on the edge trajectory of the aligner are adjusted towards the gum line so that the edge trajectory of the aligner meets the user's expected removal force. This yields a set of sample data, including crown height, undercut depth, material performance data, and coordinates of multiple control points corresponding to the preset edge line.

[0493] Based on any of the above embodiments, the first mapping relationship may include a correspondence relationship. For example, the first mapping relationship may include the relationship between at least one of preset tooth feature data and preset material performance data and the coordinates of multiple control points corresponding to a preset edge line. The relationship between the first mapping relationship including preset tooth feature data and preset material performance data and the preset edge line can be illustrated by the following example, which will not be repeated below. For instance, the first mapping relationship includes the correspondence between at least one of preset tooth feature data and preset material performance data and the coordinates of multiple control points corresponding to a preset edge line. The electronic device generates multiple target control point coordinates based on the user's tooth feature data and at least one of the performance data of the material used to manufacture the user's orthodontic appliance, and this correspondence relationship. Then, based on the multiple target control point coordinates, it generates the coordinates of multiple target control points for the edge line of the first orthodontic appliance. For example, the first mapping relationship may include a functional relationship between at least one of the preset tooth feature data and preset material performance data and the coordinates of multiple control points corresponding to the preset edge line. The electronic device generates multiple target control point coordinates based on the user's tooth feature data and at least one of the performance data of the material used to manufacture the user's orthodontic appliance, as well as the functional relationship, and then generates the first orthodontic appliance edge line based on the multiple target control point coordinates.

[0494] In some embodiments of this application, machine learning can be used to accelerate the calculation of target control point coordinates for the edge line of the first orthodontic appliance. For example, a target model can be used to generate the target control point coordinates for the edge line of the first orthodontic appliance. The target model is used to establish a first mapping relationship between at least one of preset tooth feature data and preset material performance data and the coordinates of multiple control points corresponding to the preset edge line. This application does not limit the type and training method of the target model, and examples include, but are not limited to, neural network models and deep neural network models.

[0495] Taking the example of an electronic device training a target model based on multiple sets of sample data, the multiple sets of sample data include preset tooth feature data and multiple control point coordinates corresponding to preset edge lines. The electronic device inputs the user's tooth feature data into the target model, obtains multiple target control point coordinates output by the model, and then generates the first orthodontic appliance edge line based on the multiple target control point coordinates output by the model, or obtains the first orthodontic appliance edge line output by the model.

[0496] For example, user tooth feature data includes crown height h1 and undercut depth h2. h1 and h2 can be input into the target model to generate multiple target control point coordinates. These multiple target control point coordinates can be used to generate the edge line of the first orthodontic appliance, or the edge line of the first orthodontic appliance can be generated directly through the target model.

[0497] In other embodiments, each set of sample data in any of the above embodiments also includes the expected removal force. Taking the sample data including at least one of the preset tooth feature data and preset material performance data as an example, the first mapping relationship also includes the expected removal force. Therefore, the first mapping relationship includes not only the relationship between the preset tooth feature data and the preset material performance data and the multiple control point coordinates corresponding to the preset edge line, but also the relationship between the preset edge line and the preset removal force. The determination of the first orthodontic appliance edge line based on the user's tooth feature data and at least one of the performance data of the material used to manufacture the user's orthodontic appliance can be achieved in the following way: the electronic device generates a first orthodontic appliance edge line that meets the user's expected removal force based on the user's tooth feature data and at least one of the performance data of the material used to manufacture the user's orthodontic appliance, the user's expected removal force, and the first mapping relationship.

[0498] In this embodiment, the expected removal force for different users can be determined based on the user's dental condition. For example, it can be set according to the user's age; for instance, the expected removal force for adults can be set to 7-10N, and the expected removal force for teenagers can be set to 1-6N. Alternatively, a uniform value can be set for the expected removal force in each age group. Another example is that it can be set based on whether the user has periodontal disease and the severity of the periodontal disease. The expected removal force can also be determined by combining the user's age and the presence or absence of periodontal disease, among other factors. This application does not limit the specific method for determining the user's expected removal force.

[0499] Taking the example of an electronic device training a target model based on multiple sets of sample data, the multiple sets of sample data include preset tooth feature data, multiple control point coordinates corresponding to preset edge lines, and preset removal and wearing force. The electronic device inputs the user's tooth feature data and the user's expected removal and wearing force into the target model, obtains multiple target control point coordinates output by the model, and then generates a first aligner edge line that meets the user's expected removal and wearing force based on the multiple target control point coordinates output by the model, or obtains the first aligner edge line that meets the user's expected removal and wearing force output by the model.

[0500] For example, user tooth feature data includes crown height h1 and undercut depth h2. The user's expected removal force is K. h1, h2, and K can be input into the target model to generate multiple target control point coordinates. These multiple target control point coordinates can be used to generate the first aligner edge line that satisfies the expected removal force K, or directly generate the first aligner edge line that satisfies the expected removal force K.

[0501] When establishing the first mapping relationship in any of the above embodiments based on multiple sets of sample data, the parameters included in at least one of the following in the sample data—the user's dental feature data and the performance data of the materials used to manufacture the user's orthodontic appliance—can be adjusted according to their respective weights. Then, the first mapping relationship is established based on the weighted sample data. The weight corresponding to any parameter represents the proportion of contribution of that parameter to the difficulty of removing and wearing the orthodontic appliance. The larger the weight of a parameter, the greater its contribution to the difficulty of removing and wearing the orthodontic appliance, and the more difficult the appliance is to remove.

[0502] Taking the sample data, which includes the user's tooth feature data and the coordinates of multiple control points corresponding to the preset edge line, as an example, the user's tooth feature data includes the crown height h1 and the undercut depth h2. The weight corresponding to the crown height is w1, and the weight corresponding to the undercut depth is w2. w1*h1 and w2*h2 can be input into the target model to generate multiple target control point coordinates or directly generate the edge line of the first orthodontic appliance.

[0503] The edge line generation method provided in this application embodiment can generate reasonable orthodontic appliance edge lines. For example, the schematic diagram of orthodontic appliance edge lines shown in Figure 37 shows that (a) in Figure 37 is the edge line of user A's orthodontic appliance, which is generated based on extracting user A's tooth feature data from user A's digital dental model, and then generating it according to at least one of user A's tooth feature data and the performance data of the material used to manufacture the user's orthodontic appliance; (b) in Figure 37 is the edge line of user B's orthodontic appliance, which is generated based on extracting user A's tooth feature data from user B's digital dental model, and then generating it according to at least one of user B's tooth feature data and the performance data of the material used to manufacture the user's orthodontic appliance.

[0504] Based on the same concept, this application also provides a method for manufacturing an orthodontic appliance. This method can be performed by an electronic device or a component inside the electronic device. For ease of description, the following embodiments use an electronic device as an example. The electronic device performs edge cutting on the orthodontic appliance to be cut corresponding to the digital dental model according to the first edge line of the orthodontic appliance. The orthodontic appliance to be cut is obtained by pressing material based on a solid dental model corresponding to the digital jaw model. The first edge line of the orthodontic appliance is generated according to the edge line generation method in any of the foregoing embodiments. For specific implementation, please refer to the relevant content of the edge line generation method in the foregoing embodiments, which will not be repeated here. The orthodontic appliance manufactured by this method maintains sufficient wrapping force and application force while being easy for the user to wear and remove.

[0505] In one possible implementation, a physical tooth model is created based on the user's digital dental model. Then, a diaphragm is pressed onto the physical tooth model to form the orthodontic appliance to be cut. The appliance is then edge-cut according to the edge line of the first appliance to obtain the target appliance. This target appliance can be worn on the user's teeth. The edge cutting of the appliance can be performed using cutting and trimming techniques such as scalpels, lasers, water jets, or grinding.

[0506] In this embodiment of the application, the edge cutting of the orthodontic appliance to be cut can be performed automatically or manually.

[0507] In the case of manual cutting, the cutting path needs to be indicated on the orthodontic appliance to be cut. In one possible implementation, a cutting indicator line is formed on the appliance to be cut based on the edge line of the first orthodontic appliance. The appliance is then cut along the edge of the appliance according to the cutting indicator line to obtain the target orthodontic appliance. The cutting indicator line indicates the edge cutting path of the appliance to be cut. This method facilitates manual cutting of the appliance edges.

[0508] Based on the same concept, this application also provides a display method. Figure 38 is a flowchart illustrating a display method provided in an embodiment of this application. This display method can be executed by an electronic device or a component inside an electronic device. For ease of description, the following embodiments use execution by an electronic device as an example. As shown in Figure 38, the display method includes the following steps:

[0509] Step 3801: Display the user's digital dental model.

[0510] Step 3802: In response to the command to generate the difficulty of wearing and removing the appliance, display the difficulty of wearing and removing the appliance on the digital dental model.

[0511] The method for determining the difficulty of wearing and removing the orthodontic appliance can be found in the aforementioned edge line generation method, and will not be repeated here.

[0512] Based on the same concept, this application also provides another display method. Figure 39 is a flowchart illustrating another display method provided in an embodiment of this application. This display method can be executed by an electronic device or a component inside an electronic device. For ease of description, the following embodiments use execution by an electronic device as an example. As shown in Figure 39, the display method includes the following steps:

[0513] Step 3901: Display the user's digital dental model.

[0514] Step 3902: Display the edge line of the first orthodontic appliance.

[0515] The edge line of the first orthodontic appliance is obtained according to the edge line generation method provided in any of the foregoing embodiments.

[0516] The methods provided in the embodiments of this application above are described from the perspective of an electronic device as the executing entity. To implement the functions of the methods provided in the embodiments of this application above, the electronic device may include hardware structures and / or software modules, implementing the above functions in the form of hardware structures, software modules, or a combination of hardware structures and software modules. Whether a particular function is executed in the form of hardware structures, software modules, or a combination of hardware structures and software modules depends on the specific application and design constraints of the technical solution.

[0517] Based on the same technical concept, Figure 40 is a structural schematic diagram of a cutting path adjustment device provided in an embodiment of this application. As shown in Figure 40, the device 4000 includes:

[0518] The receiving module 4001 is used to receive an adjustment instruction for the first cutting path; the first cutting path is the cutting path corresponding to the dental model of the i-th orthodontic step.

[0519] The execution module 4002 is used to adjust the first cutting path according to the adjustment instruction;

[0520] The execution module 4002 is further configured to adjust the second cutting path of the dental model with n orthodontic steps based on the adjustment range and adjustment magnitude of the first cutting path; n is a positive integer greater than or equal to 1.

[0521] In one possible design, the device further includes a processing module 4003, which, before adjusting the second cutting paths of the dental model for the n orthodontic steps, determines the n orthodontic steps that follow the i-th orthodontic step based on the similarity between the first cutting path of the i-th orthodontic step and the second cutting paths of the other orthodontic steps.

[0522] In one possible design, when the processing module 4003 determines the n correction steps that follow the i-th correction step based on the similarity between the first cutting path of the i-th correction step and the second cutting paths of the other correction steps, it is specifically configured to: determine a first sub-cutting path within the adjustment range indicated by the adjustment instruction from the first cutting path; for the other correction steps, determine a second sub-cutting path with the same adjustment range from the second cutting paths of the other correction steps; calculate the similarity between the first sub-cutting path and the second sub-cutting path; and select the n correction steps with a similarity greater than a set threshold as the n correction steps that follow the i-th correction step.

[0523] In one possible design, when the processing module 4003 determines a second sub-cutting path with the same adjustment range from the second cutting paths of other orthodontic steps, it is specifically used to obtain the position information of each first control point in the first sub-cutting path on the dental model; determine each second control point in the second cutting path of other orthodontic steps that has the same position information as the first control point; and take the path formed by the second control points as the second sub-cutting path.

[0524] In one possible design, the processing module 4003 is further configured to establish the position information of each control point on the cutting path on the dental model in the following manner: for each control point on the cutting path, determine the tooth or gingiva closest to the control point; if the closest control point is a tooth, then set the position information of the control point to the tooth's sequence number; if the closest control point is a gingiva, then determine the position information of the control point based on the position information of the third control point before the control point and the position information of the fourth control point after the control point; the third control point is the first control point before the control point whose position information is the tooth's sequence number, and the fourth control point is the first control point after the control point whose position information is the tooth's sequence number.

[0525] In one possible design, when receiving an adjustment instruction for the first cutting path, the receiving module 4001 is specifically used to receive a single-point adjustment instruction for the fifth control point on the first cutting path; the single-point adjustment instruction is triggered by a first operation targeting the fifth control point; when adjusting the first cutting path according to the adjustment instruction, the execution module 4002 is specifically used to perform a single-point adjustment on the fifth control point according to the single-point adjustment instruction; when adjusting the second cutting path of the dental model with n orthodontic steps based on the adjustment range and adjustment magnitude of the first cutting path, the execution module 4002 is specifically used to adjust the sixth control point of the dental model with n orthodontic steps based on the adjustment magnitude of the fifth control point; the sixth control point is the control point corresponding to the fifth control point in the n orthodontic steps.

[0526] In one possible design, when the execution module 4002 adjusts the sixth control point of the dental model for n orthodontic steps based on the adjustment range of the fifth control point, it is specifically used to determine the index of the triangular facet on the three-dimensional mesh where the fifth control point is located after adjustment; the three-dimensional mesh is a three-dimensional mesh representing teeth or a three-dimensional mesh representing gingiva; calculate the first position of the fifth control point on the triangular facet after adjustment; and for each orthodontic step, adjust the position of the sixth control point to the first position on the triangular facet corresponding to the index.

[0527] In one possible design, the receiving module 4001, when receiving an adjustment instruction for the first cutting path, is specifically used to receive a segment adjustment instruction for the first cutting path; the segment adjustment instruction is triggered by a second operation; the execution module 4002, when adjusting the first cutting path according to the adjustment instruction, is specifically used to adjust the third sub-cutting path of the corresponding segment of the first cutting path according to the segment adjustment instruction; the execution module 4002, when adjusting the second cutting path of the dental model for n orthodontic steps according to the adjustment range and adjustment magnitude of the first cutting path, is specifically used to adjust the second sub-cutting path of the dental model for n orthodontic steps according to the adjustment magnitude of the third sub-cutting path within the adjustment range of the first cutting path; the second sub-cutting path is a sub-cutting path in the n orthodontic steps with the same adjustment range as the first cutting path.

[0528] Based on the same technical concept, FIG41 exemplarily illustrates a cutting line generation apparatus 4100 provided in an embodiment of this application. As shown in FIG41, it includes: an acquisition unit 4101 and a determination unit 4102. The acquisition unit 4101 is used to acquire initial cutting lines of the entire tooth and gingiva in a digital dental model; the determination unit 4102 is used to determine, from the initial cutting lines, a first region sub-line located in the virtual tooth region of the digital dental model and a second region sub-line located in the real tooth region adjacent to the virtual tooth; based on the second region sub-line, the first region sub-line is adjusted to obtain an updated cutting line.

[0529] In one possible implementation, the real teeth adjacent to the virtual tooth are the nearest real teeth on both sides of the virtual tooth, or the real teeth adjacent to the virtual tooth are the real teeth on one side of the virtual tooth.

[0530] In one possible implementation, the determining unit 4102 is used to determine the relative low point in the second region sub-line; wherein, the points closer to the gingiva in the region sub-line are lower; determine the edge point and the middle point in the first region sub-line; wherein, the coordinate value of the middle point in the root direction is determined based on the coordinate value of the relative low point in the root direction; generate a third region sub-line based on the edge point and the middle point; the third region sub-line is used to replace the first region sub-line.

[0531] In one possible implementation, the relative low point is the lowest point in the second region sub-line.

[0532] In one possible implementation, the determining unit 4102 is used to determine the first and last points in the first region sub-line as edge points in the first region sub-line; and to determine the coordinate values ​​of the middle point on the tooth surface based on the coordinate values ​​of the first and last points on the tooth surface.

[0533] In one possible implementation, the determining unit 4102 is used to connect the edge points and the intermediate points and smooth the connection; sample the smoothed connection according to the sampling rate of the initial cutting line to obtain each sampling point; and generate a third region sub-line based on each sampling point.

[0534] In one possible implementation, the determining unit 4102 is used to determine that the intermediate point is located above the neck of the virtual tooth and does not exceed the virtual tooth.

[0535] In one possible implementation, the determining unit 4102 is used to determine the bounding box of the virtual tooth; and to determine the initial cutting line located within the bounding box as the first region sub-line located in the virtual tooth region of the digital dental model.

[0536] In one possible implementation, the determining unit 4102 is used to extend outward along the axis of the world coordinate system with the centroid of the crown of the virtual tooth in the digital dental model as the origin; determine three intersection points based on the intersection positions of the outwardly extending world coordinate axis and the surface of the crown of the virtual tooth; and determine the cuboid formed by extending the three intersection points outward as the bounding box of the virtual tooth.

[0537] In one possible implementation, the determining unit 4102 is used to take the region sub-line corresponding to the real tooth located within a predetermined distance to the left of the first region sub-line in the initial cutting line as the second region sub-line on the left; and to take the region sub-line corresponding to the real tooth located within a predetermined distance to the right of the first region sub-line in the initial cutting line as the second region sub-line on the right.

[0538] In one possible implementation, the determining unit 4102 is used to determine the lowest point in the second sub-line of the left side as the relative low point of the left side; determine the lowest point in the second sub-line of the right side as the relative low point of the right side; and determine the coordinate value of the intermediate point in the root direction based on the coordinate values ​​of the relative low point of the left side and the relative low point of the right side in the root direction.

[0539] In one possible implementation, the above-mentioned device further includes a display unit 4103, which is used to display the updated cutting line.

[0540] Figure 42 shows a schematic diagram of a device for determining the cutting line of an orthodontic appliance according to an embodiment of the present invention. The device 4200 includes: an acquisition unit 4201, used to determine an initial cutting line using a dental model; the initial cutting line characterizes the boundary between the crown and the gingiva; and a processing unit 4202, used to obtain the orthodontic appliance cutting line based on adjustment information of the initial cutting line; the adjustment information indicates the adjustment range of the initial cutting line towards the gingiva; and the orthodontic appliance cutting line is located within the gingival protrusion area of ​​the adjustment range.

[0541] Optionally, the appliance cutting line is the cutting line formed by each protruding point in the gingival region within the adjustment range.

[0542] Optionally, at least one cutting point in the orthodontic appliance cutting line is determined by distance and curvature, where the distance is the distance between the cutting point and the initial point corresponding to the initial cutting line, and the curvature is the degree of curvature of the gingival region where the cutting point is located.

[0543] Optionally, curvature is weighted higher than distance.

[0544] Optionally, the processing unit 4202 is specifically used to: based on the distance adjustment range indicated by the adjustment information of the initial cutting line, to obtain multiple adjustment cutting lines by moving the initial cutting line toward the gingiva by a set step size; and to use the adjustment cutting line that meets the requirements of the gingival protrusion area as the orthodontic appliance cutting line.

[0545] Optionally, the processing unit 4202 is specifically used to: determine multiple candidate points on the dental model for any initial point in the initial cutting line based on the distance adjustment range indicated by the adjustment information of the initial cutting line; select the cutting point corresponding to the initial point from the multiple candidate points according to the distance between each candidate point and the initial point, and the curvature of the gingival region where each candidate point is located; and generate the orthodontic appliance cutting line according to the cutting points corresponding to each initial point of the initial cutting line.

[0546] Optionally, the processing unit 4202 is specifically used to: for at least one initial point in the initial cutting line, based on the distance adjustment range indicated by the adjustment information of the initial cutting line, sample along the normal direction towards the gingiva of the initial point on the dental model within the distance adjustment range to obtain multiple candidate points of the initial point on the dental model.

[0547] Optionally, the adjustment range includes a distance adjustment range for the anterior teeth region and a distance adjustment range for the posterior teeth region; wherein the distance adjustment range for the anterior teeth region is greater than the distance adjustment range for the posterior teeth region.

[0548] Optionally, the acquisition unit 4201 is specifically used to: determine the contour information between each crown and the gingiva through the dental model; sample each initial point based on the contour information between each crown and the gingiva; and perform curve fitting on each initial point to obtain the initial cutting line.

[0549] Optionally, the initial cutting line adjustment information is obtained by inputting it into the user interface; and / or; the processing unit also includes: displaying a dental model with the orthodontic appliance cutting lines in the user interface.

[0550] Based on the same technical concept, and building upon the above embodiments, this application provides a cutting line adjustment device. Figure 43 is a schematic diagram of the structure of a cutting line adjustment device provided in some embodiments of this application. As shown in Figure 43, the device includes:

[0551] The module 4301 is used to determine the area to be adjusted in the initial cutting line using the digital model of the teeth.

[0552] The adjustment module 4302 is used to adjust the initial cutting line corresponding to the area to be adjusted towards the crown direction so that the adjusted cutting line and the outermost contour line of the crown area in the digital tooth model meet the preset requirements; the preset requirements are wearing requirements or orthodontic requirements; the adjusted cutting line is used to obtain the dental instrument corresponding to the digital tooth model.

[0553] In one possible implementation, the determining module 4301 is specifically used to project the initial cutting line and the outermost contour line in a preset direction to obtain a first projection line and a second projection line; and to determine the area to be adjusted in the initial cutting line based on the first projection line and the second projection line.

[0554] In one possible implementation, the adjustment module 4302 is specifically configured to determine the region between the first projection line and the second projection line that satisfies at least one of the following conditions as the region to be adjusted in the initial cutting line; the at least one condition includes:

[0555] The distance between the first projection line and the second projection line in any region exceeds a first threshold.

[0556] The length difference between the first projection line and the second projection line in any region exceeds the second threshold.

[0557] The area difference between the first projection line and the second projection line in any region exceeds a third threshold.

[0558] In one possible implementation, the area to be adjusted includes at least one tooth and / or the area between two adjacent teeth.

[0559] In one possible implementation, the adjustment module 4302 is specifically used to project the tooth regions corresponding to the initial cutting line and the outermost contour line in a preset direction to obtain the first projection line and the second projection line; or,

[0560] Projecting the anterior tooth region and the two posterior tooth regions corresponding to the initial cutting line and the outermost contour line respectively in a preset direction yields the first projection line and the second projection line; or,

[0561] The entire regions of the initial cutting line and the outermost contour line are projected in a preset direction to obtain the first projection line and the second projection line.

[0562] In one possible implementation, the preset direction includes at least one of the following: the long axis direction of the tooth, the disengagement direction of the dental instrument corresponding to the tooth, the direction perpendicular to the occlusal plane, the direction perpendicular to the horizontal plane, the overall disengagement direction of the dental instrument, the direction perpendicular to the plane where the anterior tooth region is located, the overall disengagement direction of the anterior tooth region, the direction perpendicular to the planes where the two posterior tooth regions are located respectively, and the overall disengagement directions of the two posterior tooth regions respectively.

[0563] The adjustment module 4302 is specifically used to adjust the initial cutting line corresponding to the area to be adjusted towards the crown direction until the adjusted cutting line and the outermost contour line of the digital tooth model in the crown area satisfy at least one of the following: the distance between the first projection line and the second projection line in any area does not exceed a first threshold; and / or, the length difference between the first projection line and the second projection line in any area does not exceed a second threshold; and / or, the area difference between the first projection line and the second projection line in any area does not exceed a third threshold.

[0564] In one possible implementation, the first threshold, the second threshold, and the third threshold are all determined based on at least one of the following conditions: the material of the dental instrument in any region, the thickness of the dental instrument in any region, the position of the teeth in any region, and the developmental state of the teeth in any region.

[0565] In one possible implementation, the determining module 4301 is further configured to, before determining the area to be adjusted in the initial cutting line, project the gingival line and the outermost contour line of the crown region of each tooth in the digital tooth model in a preset direction to obtain a third projection line and a fourth projection line; and determine that the third projection line and the fourth projection line of at least one tooth meet the adjustment requirements of the initial cutting line.

[0566] In this embodiment, the area to be adjusted in the initial cutting line is determined by the crown and neck regions of the digital tooth model. The initial cutting line corresponding to the area to be adjusted is then adjusted towards the crown so that the adjusted cutting line and the outermost contour of the crown region meet the wearing or orthodontic requirements. The adjusted cutting line is used to obtain the dental instrument corresponding to the digital tooth model, thereby optimizing the placement or dislocation of the dental instrument, reducing the risk of deformation of the dental instrument caused by forceful insertion and removal, and appropriately reducing the envelopment of the tooth, which is beneficial to the growth and development of the tooth.

[0567] Based on the same technical concept, this application provides an edge line generation device, as shown in FIG44. The edge line generation device 4400 includes an acquisition unit 4401 and a processing unit 4402.

[0568] Acquisition unit 4401 is used to acquire the user's digital dental model;

[0569] Processing unit 4402 is used to determine the difficulty of removing and wearing the orthodontic appliance corresponding to the edge line of the target appliance, based on the user's tooth feature data extracted from the digital dental model, wherein the tooth feature data is used to characterize the morphological features of the user's teeth; and to adjust the edge line of the target appliance according to the difficulty of removing and wearing the appliance to obtain a first appliance edge line; the first appliance edge line is used to generate the edge morphology of the target appliance corresponding to the digital dental model, or the first appliance edge line is the edge morphology of the target appliance.

[0570] Optionally, the processing unit 4402 is specifically used to: for a target tooth in the digital dental model, compare the parameter value corresponding to the tooth feature data of the target tooth with the threshold value corresponding to the tooth feature data to determine the difficulty of appliance removal and insertion in the area where the target tooth is located; the target tooth is any tooth in the digital dental model.

[0571] Optionally, the processing unit 4402 is further configured to: adjust the edge line of the target orthodontic appliance to obtain a first orthodontic appliance edge line based on the difficulty of removing and wearing the appliance and the edge adjustment strategy; the edge adjustment strategy includes adjusting the edge line of the appliance towards the crown direction by an amount that is positively correlated with the difficulty of removing and wearing the appliance.

[0572] Optionally, the edge adjustment strategy includes at least one of the following: the tooth's removal / adoption interval; tooth number; removal / adoption order; removal / adoption priority; and removal / adoption location.

[0573] Optionally, the processing unit 4402 is specifically used to: adjust the portion of the edge line of the target orthodontic appliance corresponding to the target tooth towards the crown direction based on the fact that the difficulty of removing and wearing the orthodontic appliance in the area where the target tooth is located is greater than the expected difficulty of removal and wearing, thereby obtaining the first edge line of the orthodontic appliance.

[0574] Optionally, the tooth feature data includes at least one of the following: crown height; tooth undercut depth; tooth crowding; tooth rotation; buccal-lingual tilt; and dental arch morphology.

[0575] Optionally, the processing unit 4402 is further configured to: determine the first orthodontic appliance edge line based on at least one of the user's dental feature data and the performance data of the material used to manufacture the target orthodontic appliance.

[0576] Optionally, the processing unit 4402 is further configured to: establish a first mapping relationship, the first mapping relationship including the relationship between at least one of preset tooth feature data and material performance data and the coordinates of multiple control points corresponding to the preset edge line; and generate a first orthodontic appliance edge line based on the user's tooth feature data and at least one of the performance data of the material used to manufacture the user's orthodontic appliance, and the first mapping relationship.

[0577] Optionally, the first mapping relationship also includes the relationship between the preset edge line and the preset removal force; the processing unit 4402 is specifically used to: generate a first orthodontic appliance edge line that satisfies the user's expected removal force based on at least one of the user's dental feature data and the performance data of the material used to manufacture the user's orthodontic appliance, the user's expected removal force, and the first mapping relationship.

[0578] Optionally, the tooth feature data includes at least one of the following: crown height, undercut depth, crowding, rotation, buccal-lingual tilt, and arch morphology.

[0579] Optionally, the processing unit 4402 is further configured to: fill the undercuts in the adjacent tooth spaces of the digital dental model; and determine the degree of filling of the undercuts in the adjacent tooth spaces based on the filling status of the undercuts.

[0580] Optionally, the performance data of the material used to manufacture the user's orthodontic appliance includes at least one of the following: the thickness of the material, the elastic modulus of the material, and the flexural stiffness of the material.

[0581] Based on the same technical concept, this application embodiment also provides a display device, as shown in FIG45, the display device 4500 including a processing unit 4502 and a display unit 4501.

[0582] When the display device 4500 executes the display mode shown in FIG6 above: the display unit 4501 is used to display the user's digital dental model; the processing unit 4502 is used to display the difficulty of wearing and removing the device on the digital dental model in response to the generation command of the difficulty of wearing and removing the device.

[0583] When the display device 4500 performs the display mode shown in FIG7 above: the display unit 4501 is used to: display the user's digital dental model; display the edge line of the first orthodontic appliance, the edge line of the first orthodontic appliance being obtained by the processing unit 4502 according to the edge line generation method described in any of the foregoing embodiments.

[0584] When implemented in hardware, the hardware implementation of this electronic device can be referred to Figure 46 and its related description.

[0585] Referring to Figure 46, the electronic device includes: a display screen 4601; one or more processors 4602; a memory 4603; one or more application programs (not shown); and one or more computer programs 4604. These devices can be connected via one or more communication buses 4605. The one or more computer programs 4604 are stored in the memory 4603 and configured to be executed by the one or more processors 4602. The one or more computer programs 4604 include instructions that can be used to perform the methods provided in any of the above embodiments.

[0586] This application also provides an orthodontic appliance, which can be single or a series; at least one orthodontic appliance is manufactured using the edge line generation method provided in any of the foregoing embodiments or the first orthodontic appliance edge line in the foregoing display method.

[0587] This application also provides a computer storage medium storing computer instructions. When the computer instructions are executed on an electronic device, the electronic device performs the aforementioned method steps to implement the method provided in any of the above embodiments.

[0588] This application also provides a computer program product that, when run on a computer, causes the computer to perform the aforementioned steps to implement the method provided in any of the above embodiments.

[0589] In addition, embodiments of this application also provide an apparatus, which may specifically be a chip, an analysis item, or a module. The apparatus may include a connected processor and a memory; wherein the memory is used to store computer execution instructions, and when the apparatus is running, the processor may execute the computer execution instructions stored in the memory to cause the chip to execute the methods in the above-described method embodiments.

[0590] In this application, the electronic devices, computer storage media, computer program products or chips provided in the embodiments are all used to execute the corresponding methods provided above. Therefore, the beneficial effects they can achieve can be referred to the beneficial effects in the corresponding methods provided above, and will not be repeated here.

[0591] Through the above description of the embodiments, those skilled in the art will understand that, for the sake of convenience and brevity, 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 can be divided into different functional modules to complete all or part of the functions described above.

[0592] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of modules or units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or analysis items may be combined or integrated into another apparatus, or some features may be ignored or not executed. Furthermore, the mutual coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between apparatuses or units may be electrical, mechanical, or other forms.

[0593] The units described as separate components may or may not be physically separate. A component shown as a unit can be one or more physical units; that is, it can be located in one place or distributed in multiple different locations. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0594] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0595] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a readable storage medium. Based on this understanding, the technical solutions of the embodiments of this application, in essence, or the parts that contribute to the prior art, or all or part of the technical solutions, can be embodied in the form of a software product. This software product is stored in a storage medium and includes several instructions to cause a device (which may be a microcontroller, chip, etc.) or processor to execute all or part of the steps of the methods of the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0596] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A method for adjusting a cutting path, characterized in that, The method includes: Receive adjustment instructions for the first cutting path; the first cutting path is the cutting path corresponding to the dental model of the i-th orthodontic step; The first cutting path is adjusted according to the adjustment instruction; Based on the adjustment range and adjustment magnitude of the first cutting path, the second cutting path of the dental model with n orthodontic steps is adjusted accordingly; n is a positive integer greater than or equal to 1.

2. The method according to claim 1, characterized in that, Before adjusting the second cutting path of the dental model for n orthodontic steps, the following steps are also included: Based on the similarity between the first cutting path of the i-th correction step and the second cutting paths of the other correction steps, n correction steps that follow the i-th correction step are determined.

3. The method according to claim 2, characterized in that, Based on the similarity between the first cutting path of the i-th correction step and the second cutting paths of the other correction steps, n correction steps that follow the i-th correction step are determined, including: From the first cutting path, determine the first sub-cutting path within the adjustment range indicated by the adjustment command; For each of the other correction steps, a second sub-cutting path with the same adjustment range is determined from the second cutting paths of the other correction steps; the similarity between the first sub-cutting path and the second sub-cutting path is calculated; The n correction steps with similarity greater than a set threshold are taken as the n correction steps that follow the i-th correction step.

4. The method according to claim 3, characterized in that, Determining a second sub-cutting path with the same adjustment range from the second cutting paths of other correction steps includes: Obtain the position information of each first control point within the first sub-cutting path on the dental model; Identify the second control points in the second cutting path of other correction steps that have the same positional information as the first control point; The paths formed by the second control points are used as the second sub-cutting paths.

5. The method according to claim 4, characterized in that, The positional information of each control point on the cutting path on the dental model is established using the following method: For each control point on the cutting path, determine the tooth or gingiva that is closest to the control point; If the closest object to the control point is a tooth, then the position information of the control point is set as the sequence number of the tooth; If the closest point to the control point is the gingiva, then the position information of the control point is determined based on the position information of the third control point before the control point and the position information of the fourth control point after the control point; the third control point is the first control point whose position information before the control point is the tooth number, and the fourth control point is the first control point whose position information after the control point is the tooth number.

6. The method according to claim 1, characterized in that, Receive adjustment instructions for the first cutting path, including: Receive a single-point adjustment instruction for the fifth control point on the first cutting path; the single-point adjustment instruction is triggered by a first operation on the fifth control point. Adjusting the first cutting path according to the adjustment instruction includes: The fifth control point is adjusted according to the single-point adjustment instruction. Based on the adjustment range and magnitude of the first cutting path, the second cutting path of the dental model with n orthodontic steps is adjusted accordingly, including: Based on the adjustment range of the fifth control point, the sixth control point of the dental model for n orthodontic steps is adjusted accordingly; the sixth control point is the control point corresponding to the fifth control point in the n orthodontic steps.

7. The method according to claim 6, characterized in that, Based on the adjustment range of the fifth control point, the sixth control point of the dental model for n orthodontic steps is adjusted accordingly, including: Determine the index of the triangular facet on the three-dimensional mesh where the fifth control point is located after adjustment; the three-dimensional mesh is a three-dimensional mesh representing teeth or a three-dimensional mesh representing gingiva; Calculate the first position of the fifth control point on the triangular facet after adjustment; For each correction step, the position of the sixth control point is adjusted to the first position on the triangular facet corresponding to the index.

8. The method according to claim 1, characterized in that, Receive adjustment instructions for the first cutting path, including: Receive a segment adjustment instruction for the first cutting path; the segment adjustment instruction is triggered by a second operation; Adjusting the first cutting path according to the adjustment instruction includes: The third sub-cutting path of the corresponding segment of the first cutting path is adjusted according to the segment adjustment instruction; Based on the adjustment range and magnitude of the first cutting path, the second cutting path of the dental model for n orthodontic steps is adjusted accordingly, including: Based on the adjustment range of the third sub-cutting path within the adjustment range of the first cutting path, the second sub-cutting path of the dental model of n orthodontic steps is adjusted accordingly; the second sub-cutting path is the sub-cutting path in the n orthodontic steps with the same adjustment range as the first cutting path.

9. A method for generating a cutting line, characterized in that, include: Obtain the initial cutting lines for the entire tooth and gingiva in the digital dental model; A first region sub-line located in the virtual tooth region of the digital dental model and a second region sub-line located in the real tooth region adjacent to the virtual tooth are determined from the initial cutting line. Based on the second region sub-line, the first region sub-line is adjusted to obtain an updated cutting line.

10. The method according to claim 9, characterized in that, The real teeth adjacent to the virtual tooth are the nearest real teeth on both sides of the virtual tooth, or The real tooth adjacent to the virtual tooth is the real tooth on one side of the virtual tooth.

11. The method according to claim 9, characterized in that, The adjustment of the first region sub-line based on the second region sub-line includes: Determine the relative low point within the second sub-region; wherein, the points closer to the gum line within the sub-region are lower. Determine the edge points and midpoints in the first region sub-line; wherein the coordinates of the midpoint in the root direction are determined based on the coordinates of the relative low point in the root direction. A third region sub-line is generated based on the edge point and the midpoint; the third region sub-line is used to replace the first region sub-line.

12. The method according to claim 11, characterized in that, The relative low point is the lowest point in the second region sub-line.

13. The method according to claim 9, characterized in that, Determining the edge points and midpoints in the first region sub-line includes: The first and last points in the first region sub-line are determined as the edge points in the first region sub-line; Based on the coordinates of the first and last points on the tooth surface, the coordinates of the middle point on the tooth surface are determined.

14. The method according to claim 11, characterized in that, The step of generating a third region sub-line based on the edge points and the midpoints includes: Connect the edge points and the middle points with a line and smooth the connection. The smoothed connection is sampled according to the sampling rate of the initial cutting line to obtain each sampling point; A third region sub-line is generated based on each sampling point.

15. The method according to claim 11, characterized in that, After determining the edge points and midpoints in the first region sub-line, and before generating the third region sub-line, the process further includes: The midpoint is determined to be located above the neck of the virtual tooth and not exceeding the virtual tooth.

16. The method according to any one of claims 9 to 15, characterized in that, The step of determining the first region sub-line located in the virtual tooth region of the digital dental model from the initial cutting line includes: Determine the bounding box of the virtual teeth; The initial cutting line located within the bounding box is defined as the first region sub-line located in the virtual tooth region of the digital dental model.

17. The method according to claim 16, characterized in that, The process of determining the bounding box of the virtual tooth includes: Taking the centroid of the crown of the virtual tooth in the digital dental model as the origin, extend outward along the axis of the world coordinate system; Based on the intersection of the outwardly extending world coordinate axis with the surface of the crown of the virtual tooth, three intersection points are determined; The cuboid formed by extending the three intersection points outwards is defined as the bounding box of the virtual tooth.

18. The method according to any one of claims 9 to 16, characterized in that, Determining a second region sub-line from the initial cutting line, located in the region of a real tooth adjacent to the virtual tooth, includes: The region sub-line corresponding to the real tooth located within a set distance to the left of the first region sub-line in the initial cutting line is taken as the second region sub-line on the left. The region sub-line corresponding to the actual tooth located within a set distance to the right of the first region sub-line in the initial cutting line is taken as the second region sub-line on the right.

19. The method according to claim 18, characterized in that, Determining the relative low point within the second region sub-line includes: Determine the lowest point in the second sub-line on the left as the relative low point on the left; Determine the lowest point in the second sub-line on the right as the relative low point on the right; The coordinates of the midpoint in the root direction are determined based on the coordinates of the relative low point in the root direction, including: The coordinates of the midpoint in the root direction are determined based on the coordinates of the relative low point on the left and the relative low point on the right in the root direction.

20. The method according to any one of claims 9 to 15, characterized in that, Showing the updated cut line.

21. A method for determining the cutting line of an orthodontic appliance, characterized in that, include: The initial cutting line was determined using a dental model; The initial cutting line is used to characterize the boundary between the crown and the gingiva; Based on the adjustment information of the initial cutting line, the orthodontic appliance cutting line is obtained through the initial cutting line; the adjustment information is used to indicate the adjustment range of the initial cutting line toward the gingiva; the orthodontic appliance cutting line is located in the gingival protrusion area within the adjustment range.

22. The method according to claim 21, characterized in that, The cutting line of the orthodontic appliance is the cutting line formed by each protruding point in the gingival region within the adjustment range.

23. The method according to claim 21, characterized in that, At least one cutting point in the orthodontic appliance cutting line is determined by distance and curvature, wherein the distance is the distance between the cutting point and the initial point corresponding to the initial cutting line, and the curvature is the degree of curvature of the gingival region where the cutting point is located.

24. The method according to claim 23, characterized in that, The curvature has a higher weight than the distance.

25. The method according to claim 21, characterized in that, Based on the adjustment information of the initial cutting line, the orthodontic cutting line is obtained through the initial cutting line, including: Based on the distance adjustment range indicated by the adjustment information of the initial cutting line, multiple adjustment cutting lines are obtained by moving the initial cutting line toward the gum line by a set step size; the adjustment cutting line that meets the requirements of the gum protrusion area is used as the cutting line of the orthodontic appliance.

26. The method according to claim 21, characterized in that, Based on the adjustment information of the initial cutting line, the orthodontic cutting line is obtained through the initial cutting line, including: Based on the distance adjustment range indicated by the adjustment information of the initial cutting line, multiple alternative points are determined on the dental model for any initial point of the initial cutting line. Based on the distance between each candidate point and the initial point, and the curvature of the gingival region where each candidate point is located, the cutting point corresponding to the initial point is selected from the plurality of candidate points; Based on the cutting points corresponding to each initial point of the initial cutting line, the orthodontic cutting line is generated.

27. The method according to claim 26, characterized in that, Based on the distance adjustment range indicated by the adjustment information of the initial cutting line, multiple candidate points on the dental model are determined for any initial point in the initial cutting line, including: For at least one initial point in the initial cutting line, based on the distance adjustment range indicated by the adjustment information of the initial cutting line, sampling is performed on the dental model along the normal direction towards the gingiva from the initial point within the distance adjustment range to obtain multiple alternative points of the initial point on the dental model.

28. The method according to any one of claims 21 to 27, characterized in that, The adjustment range includes a distance adjustment range for the anterior teeth region and a distance adjustment range for the posterior teeth region; wherein the distance adjustment range for the anterior teeth region is greater than the distance adjustment range for the posterior teeth region.

29. The method according to any one of claims 21 to 27, characterized in that, The determination of the initial cutting line using a dental model includes: Using a dental model, the contour information between each tooth crown and the gingiva is determined; Based on the contour information between each tooth crown and the gingiva, each initial point is sampled; Curve fitting is performed on each initial point to obtain the initial cutting line.

30. The method according to any one of claims 21 to 27, characterized in that, The initial cutting line adjustment information is obtained by inputting it into the user interface; and / or After obtaining the orthodontic appliance cutting line, the following is also included: The user interface displays a dental model with the cutting lines of the orthodontic appliance.

31. An orthodontic appliance, characterized in that, The orthodontic appliance is shell-shaped and includes multiple cavities for accommodating teeth; when the orthodontic appliance is worn in the user's mouth, the edge of the orthodontic appliance is located in the user's gingival protrusion area.

32. The orthodontic appliance according to claim 31, characterized in that, The edge line of the orthodontic appliance is located at each protruding point in the gingival region within the adjustment range; the adjustment range is derived from the adjustment instructions for the initial cutting line.

33. The orthodontic appliance according to claim 31, characterized in that, The edge line of the orthodontic appliance is obtained by the orthodontic appliance cutting line obtained by the method described in any one of claims 1 to 30.

34. A method for adjusting cutting lines, characterized in that, The method includes: Using a digital model of the teeth, the area to be adjusted within the initial cutting line is determined; The initial cutting line corresponding to the area to be adjusted is adjusted towards the crown direction so that the adjusted cutting line and the outermost contour line of the crown area in the digital tooth model meet the preset requirements; the preset requirements are wearing requirements or orthodontic requirements; the adjusted cutting line is used to obtain the dental instrument corresponding to the digital tooth model.

35. The method according to claim 34, characterized in that, The process of determining the area to be adjusted within the initial cutting line using a digital model of the teeth includes: The initial cutting line and the outermost contour line are projected in a preset direction to obtain a first projection line and a second projection line; based on the first projection line and the second projection line, the area to be adjusted in the initial cutting line is determined.

36. The method according to claim 35, characterized in that, The step of determining the area to be adjusted in the initial cutting line based on the first projection line and the second projection line includes: The region between the first projection line and the second projection line that satisfies at least one of the following conditions is identified as the region to be adjusted in the initial cutting line; the at least one condition includes: The distance between the first projection line and the second projection line in any region exceeds a first threshold. The length difference between the first projection line and the second projection line in any region exceeds the second threshold. The area difference between the first projection line and the second projection line in any region exceeds a third threshold.

37. The method according to any one of claims 34-36, characterized in that, The area to be adjusted includes at least one tooth and / or the area between two adjacent teeth.

38. The method according to claim 35, characterized in that, The step of projecting the initial cutting line and the outermost contour line in a preset direction to obtain a first projection line and a second projection line includes: Projecting the tooth regions corresponding to the initial cutting line and the outermost contour line in a preset direction respectively, to obtain the first projection line and the second projection line; or, Projecting the anterior tooth region and the two posterior tooth regions corresponding to the initial cutting line and the outermost contour line respectively in a preset direction yields the first projection line and the second projection line; or, The entire regions of the initial cutting line and the outermost contour line are projected in a preset direction to obtain the first projection line and the second projection line.

39. The method according to claim 35 or 38, characterized in that, The preset direction includes at least one of the following: the long axis direction of the tooth, the disengagement direction of the dental instrument corresponding to the tooth, the direction perpendicular to the occlusal plane, the direction perpendicular to the horizontal plane, the overall disengagement direction of the dental instrument, the direction perpendicular to the plane where the anterior tooth region is located, the overall disengagement direction of the anterior tooth region, the direction perpendicular to the planes where the two posterior tooth regions are located respectively, and the overall disengagement direction of the two posterior tooth regions respectively.

40. The method according to claim 34, characterized in that, The step of adjusting the initial cutting line corresponding to the area to be adjusted towards the crown direction, so that the adjusted cutting line and the outermost contour line of the digital tooth model in the crown area meet preset requirements, includes: Adjust the initial cutting line corresponding to the area to be adjusted towards the crown direction until the adjusted cutting line and the outermost contour line of the digital tooth model in the crown region satisfy at least one of the following: The distance between the first projection line and the second projection line in any region does not exceed a first threshold; and / or, the length difference between the first projection line and the second projection line in any region does not exceed a second threshold; and / or, the area difference between the first projection line and the second projection line in any region does not exceed a third threshold.

41. The method according to claim 36 or 40, characterized in that, The first threshold, the second threshold, and the third threshold are all determined based on at least one of the following conditions: the material of the dental instrument in any region, the thickness of the dental instrument in any region, the position of the teeth in any region, and the developmental state of the teeth in any region.

42. The method according to claim 34 or 35, characterized in that, Before determining the area to be adjusted in the initial cutting line, the process also includes: The gingival line and the outermost contour line of the crown region of each tooth in the digital tooth model are projected in a preset direction to obtain the third projection line and the fourth projection line; it is determined that the third projection line and the fourth projection line of at least one tooth meet the adjustment requirements of the initial cutting line.

43. A dental instrument, characterized in that, The dental instrument has a shell-like structure; The outline of the opening of the shell-like structure and the outermost outline of the dental instrument in the crown area meet preset requirements; the preset requirements are to meet the wearing requirements or orthodontic requirements of the dental instrument; the opening of the shell-like structure is obtained by cutting lines and the corresponding digital model of the teeth of the dental instrument.

44. The dental instrument according to claim 43, characterized in that, The opening contour line and the outermost contour line satisfy the preset requirements by obtaining the first projection line of the opening contour line in the preset direction and the second projection line of the outermost contour line in the preset direction.

45. The dental instrument according to claim 44, characterized in that, The preset requirements are that the distance between the first projection line and the second projection line in any region does not exceed a first threshold; and / or, the length difference between the first projection line and the second projection line in any region does not exceed a second threshold; and / or, the area difference between the first projection line and the second projection line in any region does not exceed a third threshold.

46. ​​The dental instrument according to claim 44, characterized in that, The preset direction includes at least one of the following: the long axis direction of the tooth, the disengagement direction of the dental instrument corresponding to the tooth, the direction perpendicular to the occlusal plane, the direction perpendicular to the horizontal plane, the overall disengagement direction of the dental instrument, the plane where the anterior tooth region is located, the overall disengagement direction of the anterior tooth region, the planes where the two posterior tooth regions are located respectively, and the overall disengagement directions of the two posterior tooth regions respectively.

47. The dental instrument according to claim 45, characterized in that, The first threshold, the second threshold, and the third threshold are all determined based on at least one of the following conditions: the material of the dental instrument in any region, the thickness of the dental instrument in any region, the position of the teeth in any region, and the developmental state of the teeth in any region.

48. A method for generating edge lines, characterized in that, include: Obtain the user's digital dental model; Based on the user's dental feature data extracted from the digital dental model, the difficulty of removing and inserting the orthodontic appliance is determined with the user's gingival margin as the target appliance edge line. The dental feature data is used to characterize the morphological features of the user's teeth. Based on the difficulty of wearing and removing the orthodontic appliance, the edge line of the target orthodontic appliance is adjusted to obtain the first edge line of the orthodontic appliance; the first edge line of the orthodontic appliance is used to generate the edge shape of the target orthodontic appliance corresponding to the digital dental model, or the first edge line of the orthodontic appliance is the edge shape of the target orthodontic appliance.

49. The method according to claim 48, characterized in that, The determination of the difficulty of inserting and removing the orthodontic appliance, with the user's gingival margin as the target appliance edge line, includes: For a target tooth in the digital dental model, the parameter values ​​corresponding to the tooth feature data of the target tooth are compared with the threshold values ​​corresponding to the tooth feature data to determine the difficulty of appliance insertion and removal in the area where the target tooth is located; the target tooth is any tooth in the digital dental model.

50. The method according to claim 48 or 49, characterized in that, The method further includes: Based on the difficulty of removing and wearing the orthodontic appliance and the edge adjustment strategy, the edge line of the target orthodontic appliance is adjusted to obtain the first orthodontic appliance edge line; the edge adjustment strategy includes the fact that the adjustment range of the orthodontic appliance edge line towards the crown is positively correlated with the difficulty of removing and wearing the orthodontic appliance.

51. The method according to claim 50, characterized in that, The edge adjustment strategy includes at least one of the following: the tooth's removal / wearing interval; tooth number; removal / wearing order; removal / wearing priority; and removal / wearing location.

52. The method according to claim 50, characterized in that, The step of adjusting the edge line of the target orthodontic appliance to obtain the first orthodontic appliance edge line based on the difficulty of wearing and removing the appliance and the edge adjustment strategy includes: Since the difficulty of removing and wearing the orthodontic appliance in the area where the target tooth is located is greater than the expected difficulty of removal and wearing, the edge line of the target orthodontic appliance corresponding to the target tooth is adjusted towards the crown direction to obtain the first edge line of the orthodontic appliance.

53. The method according to any one of claims 48-52, characterized in that, The dental feature data includes at least one of the following: Crown height; Depth of tooth undercuts; degree of tooth crowding; degree of tooth rotation; The degree of buccal-lingual inclination of the teeth; the shape of the dental arch.

54. The method according to claim 48, characterized in that, The method further includes: The first orthodontic appliance edge line is determined based on at least one of the user's dental feature data and the performance data of the material used to manufacture the target orthodontic appliance.

55. The method according to claim 54, characterized in that, The method further includes: Establish a first mapping relationship, which includes the relationship between at least one of the preset tooth feature data and material property data and a preset edge line; Determining the edge line of the first orthodontic appliance based on at least one of the user's dental feature data and the performance data of the materials used to manufacture the user's orthodontic appliance includes: The first orthodontic appliance edge line is generated based on at least one of the user's dental feature data and the performance data of the material used to manufacture the user's orthodontic appliance, as well as the first mapping relationship.

56. The method according to claim 55, characterized in that, The first mapping relationship also includes the relationship between a preset edge line and a preset removal / wearing force; determining the first orthodontic appliance edge line based on at least one of the user's dental feature data and the performance data of the materials used to manufacture the user's orthodontic appliance includes: Based on at least one of the user's dental feature data and the performance data of the material used to manufacture the user's orthodontic appliance, the user's expected removal force, and the first mapping relationship, a first orthodontic appliance edge line that satisfies the user's expected removal force is generated.

57. The method according to any one of claims 53-56, characterized in that, The tooth feature data also includes the degree of undercut filling in the interdental spaces. After obtaining the user's digital dental model, the following is also included: Fill the undercuts in the adjacent tooth spaces of the digital dental model; The degree of filling of the undercut in the interdental space is determined based on the filling condition of the undercut.

58. The method according to any one of claims 54-57, characterized in that, Performance data for materials used in manufacturing user orthodontic appliances include at least one of the following: The thickness of the material, the elastic modulus of the material, and the bending stiffness of the material.

59. A method for manufacturing an orthodontic appliance, characterized in that, include: The target orthodontic appliance is obtained by edge cutting the orthodontic appliance corresponding to the digital dental model according to the edge line of the first orthodontic appliance; wherein the edge line of the first orthodontic appliance is generated by the method according to any one of claims 48 to 58, and the orthodontic appliance to be cut is obtained by pressing a membrane based on the solid dental model corresponding to the digital dental model.

60. The method according to claim 59, characterized in that, The step of cutting the edge of the orthodontic appliance corresponding to the digital dental model according to the edge line of the first orthodontic appliance to obtain the target orthodontic appliance includes: Based on the edge line of the first orthodontic appliance, a cutting indicator line is formed on the orthodontic appliance to be cut, and the cutting indicator line is used to indicate the edge cutting path of the orthodontic appliance to be cut; According to the cutting indicator line, the edge of the orthodontic appliance to be cut is cut to obtain the target orthodontic appliance.

61. A display method, characterized in that, include: Displays the user's digital dental model; In response to the command to generate the difficulty of wearing and removing the appliance, the difficulty of wearing and removing the appliance is displayed on the digital dental model.

62. A display method, characterized in that, Also includes: Displays the user's digital dental model; The first orthodontic appliance edge line is displayed, which is obtained according to the edge line generation method as described in any one of claims 48 to 58.

63. A cutting path adjustment device, characterized in that, include: A receiving module is used to receive adjustment instructions for the first cutting path; The first cutting path is the cutting path corresponding to the dental model of the i-th orthodontic step; An execution module is used to adjust the first cutting path according to the adjustment instruction; The execution module is further configured to adjust the second cutting path of the dental model with n orthodontic steps according to the adjustment range and adjustment magnitude of the first cutting path; n is a positive integer greater than or equal to 1.

64. A cutting line generating apparatus, characterized in that, Includes an acquisition unit and a determination unit: The acquisition unit is used to acquire the initial cutting lines of the entire tooth and gingiva in the digital dental model; The determining unit is configured to determine, from the initial cutting line, a first region sub-line located in the virtual tooth region of the digital dental model and a second region sub-line located in the real tooth region adjacent to the virtual tooth; based on the second region sub-line, the first region sub-line is adjusted to obtain an updated cutting line.

65. A device for determining the cutting line of an orthodontic appliance, characterized in that, include: Acquisition unit, used to determine the initial cutting line using a dental model; The initial cutting line is used to characterize the boundary between the crown and the gingiva; The processing unit is configured to obtain an orthodontic appliance cutting line based on the adjustment information of the initial cutting line; the adjustment information is used to indicate the adjustment range of the initial cutting line toward the gingiva; the orthodontic appliance cutting line is located in the gingival protrusion area within the adjustment range.

66. A cutting line adjustment device, characterized in that, The device includes: The determination module is used to determine the area to be adjusted in the initial cutting line using a digital model of the teeth; An adjustment module is used to adjust the initial cutting line corresponding to the area to be adjusted towards the crown direction so that the adjusted cutting line and the outermost contour line of the crown area in the digital tooth model meet preset requirements; the preset requirements are wearing requirements or orthodontic requirements; the adjusted cutting line is used to obtain the dental instrument corresponding to the digital tooth model.

67. An electronic device, characterized in that, include: Memory, used to store program instructions; A processor is configured to invoke program instructions stored in the memory and execute the steps of the method according to any one of claims 1-30, 34-42, and 48-62.

68. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program, the computer program including program instructions that, when executed by a computer, cause the computer to perform the method as described in any one of claims 1-30, 34-42, and 48-62.

69. A computer program product, characterized in that, The computer program product includes: computer program code, which, when run on a computer, causes the computer to perform the method described in any one of claims 1-30, 34-42, and 48-62.

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