Three-dimensional dental crown data generation method and apparatus, and electronic device and storage medium

Abstract

The present invention relates to the technical field of tooth model digitalization. Provided are a three-dimensional dental crown data generation method and apparatus, and an electronic device and a storage medium. By means of performing spherical depth projection on three-dimensional tooth position data and three-dimensional surrounding tooth structure data of a target tooth position, tooth position depth data and surrounding tooth structure depth data can be obtained, which involves higher accuracy and reliability than other depth data acquisition means. Moreover, in the method, a dental crown depth data prediction model is used to determine dental crown depth data of the target tooth position, such that the prediction efficiency and accuracy of the dental crown depth data can be improved. Finally, in the method, the dental crown depth data is used to generate three-dimensional dental crown data of the target tooth position, such that the generation efficiency and accuracy of the three-dimensional dental crown data can be improved, automated generation of the three-dimensional dental crown data can be realized, and labor costs incurred by generating the three-dimensional dental crown data can thus be reduced.

Description

Crown three-dimensional data generation method and device, electronic equipment and storage medium

[0001] The present application claims priority to the Chinese patent application No. 202410867952.7, filed on July 01, 2024, and entitled "Crown three-dimensional data generation method and device, electronic equipment and storage medium", the whole content of which is incorporated herein by reference. TECHNICAL FIELD

[0002] The present application relates to the technical field of tooth model digitization, and in particular to a crown three-dimensional data generation method and device, electronic equipment and storage medium. BACKGROUND

[0003] In the process of tooth repair, the doctor needs to reasonably design a crown to repair the prepared tooth. In the process of tooth implantation, the doctor needs to design a crown for the implant tooth. The acquisition of the crown includes two processes, which are the generation of the crown three-dimensional model and the production of the crown entity. Among them, the generation of the crown three-dimensional model is a relatively complex process, which needs to ensure that the shape of the crown adapts to the user's tooth arrangement, meets the chewing function while maintaining the appearance.

[0004] In the prior art, a professional needs to first visually observe the tooth shape and arrangement of the user, and then use the observed information to operate a three-dimensional design software to design a crown three-dimensional model. This scheme requires high professional skills of the professional, needs to train the professional, and has high labor cost. Moreover, this process is not automatically completed, and manual operation of the professional not only reduces the generation efficiency of the crown three-dimensional model, but also easily introduces artificial errors in the crown three-dimensional model, making the crown three-dimensional model inaccurate. SUMMARY

[0005] The present application provides a crown three-dimensional data generation method and device, electronic equipment and storage medium to solve the defects in the prior art.

[0006] The present application provides a crown three-dimensional data generation method, comprising: acquiring tooth site three-dimensional data of a target tooth site and surrounding tooth three-dimensional data of the target tooth site, performing spherical depth projection on the tooth site three-dimensional data and the surrounding tooth three-dimensional data to obtain tooth site depth data and surrounding tooth depth data; based on the tooth site depth data and the surrounding tooth depth data, applying a crown depth data prediction model to determine crown depth data of the target tooth site; and based on the crown depth data of the target tooth site, generating crown three-dimensional data of the target tooth site.

[0007] The application further provides a dental crown three-dimensional data generation device, comprising: an acquisition module configured to acquire dental site three-dimensional data of a target dental site and surrounding dental body three-dimensional data of the target dental site, perform spherical depth projection on the dental site three-dimensional data and the surrounding dental body three-dimensional data to obtain dental site depth data and surrounding dental body depth data; a prediction module configured to determine dental crown depth data of the target dental site based on the dental site depth data and the surrounding dental body depth data by applying a dental crown depth data prediction model; and a generation module configured to generate dental crown three-dimensional data of the target dental site based on the dental crown depth data of the target dental site.

[0008] The application further provides an electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, and the processor implements the dental crown three-dimensional data generation method of any of the above when executing the computer program.

[0009] The application further provides a non-transitory computer-readable storage medium having a computer program stored thereon, and the computer program implements the dental crown three-dimensional data generation method of any of the above when executed by a processor.

[0010] The application further provides a computer program product comprising a computer program, and the computer program implements the dental crown three-dimensional data generation method of any of the above when executed by a processor.

[0011] The dental crown three-dimensional data generation method, device, electronic device, and storage medium provided by the application can obtain dental site depth data and surrounding dental body depth data by performing spherical depth projection on dental site three-dimensional data of a target dental site and surrounding dental body three-dimensional data, which is more accurate and reliable than other ways of obtaining depth data. Moreover, the method determines dental crown depth data of the target dental site by using a dental crown depth data prediction model, which can improve the prediction efficiency and accuracy of the dental crown depth data. Finally, the method generates dental crown three-dimensional data of the target dental site by using the dental crown depth data, which can improve the generation efficiency and accuracy of the dental crown three-dimensional data, realize the automatic generation of the dental crown three-dimensional data, and reduce the labor cost caused by generating the dental crown three-dimensional data. Overall, the method determines each depth data by the spherical depth projection method, predicts the dental crown depth data with the help of the prediction model, and generates the dental crown three-dimensional data by the spherical depth inverse projection method, which is simple, direct, and efficient. BRIEF DESCRIPTION OF DRAWINGS

[0012] In order to more clearly illustrate the technical solutions in the application or prior art, the following will briefly introduce the drawings needed in the embodiments or prior art description. Obviously, the drawings in the following description can also be used to obtain other drawings without creative labor by those skilled in the art.

[0013] Fig. 1 is a flow chart of the method for generating three-dimensional data of a dental crown according to the present application.

[0014] Fig. 2 is a schematic diagram of three-dimensional data of a dental site in a three-dimensional rectangular coordinate system according to the present application.

[0015] Fig. 3 is a schematic diagram of a dental site depth image according to the present application.

[0016] Fig. 4 is a schematic diagram of three-dimensional data of a target dental site in a three-dimensional rectangular coordinate system according to the present application.

[0017] Fig. 5 is a schematic diagram of a counter dental site depth image according to the present application.

[0018] Fig. 6 is a schematic diagram of three-dimensional data of a neighboring dental site of a target dental site in a three-dimensional rectangular coordinate system according to the present application.

[0019] Fig. 7 is a schematic diagram of a neighboring dental site depth image according to the present application.

[0020] Fig. 8 is a flow chart of a process for obtaining a dental crown depth image of a target dental site by inputting a superimposition result into a dental crown depth data prediction model according to the present application.

[0021] Fig. 9 is a schematic diagram of three-dimensional data of a dental site edge of a target dental site in a three-dimensional rectangular coordinate system according to the present application.

[0022] Fig. 10 is a schematic diagram of a two-dimensional line of a dental site edge according to the present application.

[0023] Fig. 11 is a schematic diagram of a correction mask according to the present application.

[0024] Fig. 12 is a flow chart of a process for obtaining three-dimensional data of a dental crown of a target dental site by performing spherical depth back-projection on corrected dental crown depth data according to the present application.

[0025] Fig. 13 is a schematic diagram of the morphology of a dental arch before and after the determination of three-dimensional data of a dental crown of a target dental site according to the present application.

[0026] Fig. 14 is a schematic diagram of a structure of a device for generating three-dimensional data of a dental crown according to the present application.

[0027] Fig. 15 is a schematic diagram of a structure of an electronic device according to the present application. DETAILED DESCRIPTION

[0028] In order to make the objects, technical solutions and advantages of the present application clearer, the technical solutions in the present application will be described clearly and completely below in conjunction with the drawings in the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work belong to the protection scope of the present application. The terms "first", "second" in the specification and claims of the present application can include one or more features explicitly or implicitly. In the description of the application, unless otherwise specified, the meaning of "a plurality of" is two or more. In addition, "and / or" in the specification and claims indicates at least one of the connected objects, and the character " / ", generally indicates that the front and rear associated objects are in an "or" relationship. In the related art, in the process of generating a three-dimensional crown model, it is usually necessary to give a user an intraoral scanning model with a tooth preparation or a base connected with an implant. A professional person first visually observes the tooth shape and arrangement of the intraoral scanning model, and then uses the observed information to operate a three-dimensional design software to design a three-dimensional crown model. This scheme not only has high labor cost, but also limits the generation efficiency and accuracy of the three-dimensional crown model. Based on this, the embodiments of the present application provide a three-dimensional crown data generation method to solve the problems of high labor cost, low generation efficiency and poor accuracy in the process of generating a three-dimensional crown model.

[0029] Fig. 1 is a flowchart of a three-dimensional crown data generation method provided in the embodiments of the present application. As shown in Fig. 1, the method comprises the following steps: S1, obtaining tooth site three-dimensional data of a target tooth site and surrounding tooth three-dimensional data of the target tooth site, performing spherical depth projection on the tooth site three-dimensional data and the surrounding tooth three-dimensional data to obtain tooth site depth data and surrounding tooth depth data; S2, based on the tooth site depth data and the surrounding tooth depth data, applying a crown depth data prediction model to determine the crown depth data of the target tooth site; S3, based on the crown depth data of the target tooth site, generating three-dimensional crown data of the target tooth site.

[0030] Specifically, the three-dimensional crown data generation method provided in the embodiments of the present application has a processor as an execution subject. The processor can be configured in a computer, which can be a local computer or a cloud computer. The local computer can be a computer, a tablet, etc., which is not specifically limited here.

[0031] In the step S1, the tooth site three-dimensional data of the target tooth site and the surrounding tooth three-dimensional data of the target tooth site are acquired. The target tooth site refers to a tooth site for which the three-dimensional data of the tooth crown is to be determined, and at the target tooth site, a target object can be included, which can be a target tooth prepared by polishing the surrounding tooth of a natural tooth of a patient, or a base connected with an implant installed for a dental implant of the patient. It can be seen that the three-dimensional data generation method of the tooth crown provided in the embodiment of the application can be applied to a dental restoration scene to design a tooth crown for a prepared tooth, and can also be applied to a dental implant scene to design a tooth crown for a dental implant.

[0032] When applied to the dental restoration scene, the acquired tooth site three-dimensional data of the target tooth site is three-dimensional scanning data of the target tooth site in which the target prepared tooth already exists.

[0033] When applied to the dental implant scene, the acquired tooth site three-dimensional data of the target tooth site is three-dimensional scanning data of the target tooth site in which the base is installed.

[0034] The tooth site three-dimensional data refers to three-dimensional data of a target object at a target tooth site, which can be a three-dimensional model or a three-dimensional point cloud, and the form of the three-dimensional data of the target tooth site is not specifically limited.

[0035] The surrounding tooth three-dimensional data refers to three-dimensional data of the surrounding tooth of the target tooth site, which can also be a three-dimensional model or a three-dimensional point cloud, and the form of the three-dimensional data of the surrounding tooth is also not specifically limited. The surrounding tooth of the target tooth site can include at least one of the adjacent tooth and the opposite tooth of the target tooth site, and the opposite tooth of the target tooth site can include the directly opposite tooth of the target tooth site, and can also include the adjacent tooth of the directly opposite tooth. The adjacent tooth of the target tooth site can include at least one, and the opposite tooth of the target tooth site can also include at least one.

[0036] The tooth site three-dimensional data and the surrounding tooth three-dimensional data can be obtained by means of artificial intelligence (AI) technology, by performing intraoral scanning on a user to obtain intraoral three-dimensional data, then dividing the intraoral three-dimensional data into tooth three-dimensional data and non-tooth three-dimensional data, and finally dividing from the tooth three-dimensional data, or can be obtained by manually taking a mold by using alginate and silicone rubber and the like. In addition, the surrounding tooth three-dimensional data can also be obtained through historical scanning data of the user, and the tooth site three-dimensional data can be obtained by scanning the target tooth site.

[0037] The tooth site depth data and the surrounding tooth body depth data can be obtained by spherical depth projection on the tooth site three-dimensional data and the surrounding tooth body three-dimensional data. Here, the spherical depth projection can be performed on the tooth site three-dimensional data and the surrounding tooth body three-dimensional data simultaneously, or the spherical depth projection can be performed on the tooth site three-dimensional data and the surrounding tooth body three-dimensional data respectively, i.e. the tooth site depth data is obtained by spherical depth projection on the tooth site three-dimensional data, and the surrounding tooth body depth data is obtained by spherical depth projection on the surrounding tooth body three-dimensional data.

[0038] The spherical depth projection refers to the process of converting the three-dimensional data to the depth data. In general, a fixed point can be selected as the center of the sphere, and then the three-dimensional data points can be converted to the depth data points according to the distance from the fixed point to the three-dimensional data points and the direction of the line connecting the fixed point and the three-dimensional data points. The depth data points can represent the distance from the fixed point to the three-dimensional data points in the direction of the line connecting the fixed point and the three-dimensional data points. Here, the depth data can be a depth image, and the depth data points can be pixel points in the depth image. The fixed point can be selected as needed, and is preferably a point other than the three-dimensional data.

[0039] Therefore, the tooth site depth data can be the depth data of the target object at the target tooth site, and the tooth site depth data points can represent the distance from the first fixed point to the tooth site three-dimensional data points in the direction of the line connecting the first fixed point and the tooth site three-dimensional data points. The surrounding tooth body depth data can be the depth data of the surrounding tooth body of the target tooth site, and the surrounding tooth body depth data points can represent the distance from the second fixed point to the surrounding tooth body three-dimensional data points in the direction of the line connecting the second fixed point and the surrounding tooth body three-dimensional data points. The first fixed point and the second fixed point can be the same or different, and are not limited here.

[0040] In step S2, a pre-trained crown depth data prediction model is introduced. The crown depth data prediction model is trained to learn the corresponding relationship between the tooth site depth data, the surrounding tooth body depth data and the crown depth data of the target tooth site, and then the tooth site depth data and the surrounding tooth body depth data are input into the crown depth data prediction model to obtain the crown depth data of the target tooth site output by the crown depth data prediction model.

[0041] The crown depth data prediction model can be constructed by a neural network model to obtain an initial prediction model, and then a suitable training sample is selected to perform supervised training on the initial prediction model. The specific structure of the neural network model can be set as needed, for example, it can be a convolutional neural network, a Transformer, etc., and is not limited here. The crown depth data of the target tooth site refers to the depth data of the crown of the target tooth site, and its representation form can be a depth image.

[0042] It should be noted that since the surrounding teeth of the target tooth site include at least one of the adjacent teeth and the opposite teeth of the target tooth site, when the surrounding teeth only have the opposite teeth without the adjacent teeth, the adjacent teeth depth data is missing in the surrounding teeth depth data obtained by the spherical surface depth projection. Therefore, when applying the crown depth data prediction model, the adjacent teeth depth data can be introduced on the basis of the tooth site depth data and the surrounding teeth depth data, and the tooth site depth data, the surrounding teeth depth data and the adjacent teeth depth data are all input into the crown depth data prediction model, and the crown depth data of the target tooth site is output by the crown depth data prediction model. Here, the adjacent teeth depth data can be the mean value of the adjacent teeth depth data of the target tooth site determined in advance, or can be predicted by AI technology in combination with the tooth site depth data and the surrounding teeth depth data, for example, the missing adjacent teeth depth data can be predicted by inputting the tooth site depth data and the surrounding teeth depth data into an AI model.

[0043] When the surrounding teeth only have the adjacent teeth without the opposite teeth, the opposite teeth depth data is missing in the surrounding teeth depth data obtained by the spherical surface depth projection. Therefore, when applying the crown depth data prediction model, the opposite teeth depth data can be introduced on the basis of the tooth site depth data and the surrounding teeth depth data, and the tooth site depth data, the surrounding teeth depth data and the opposite teeth depth data are all input into the crown depth data prediction model, and the crown depth data of the target tooth site is output by the crown depth data prediction model. Here, the opposite teeth depth data can be the mean value of the opposite teeth depth data of the target tooth site determined in advance, or can be predicted by AI technology in combination with the tooth site depth data and the surrounding teeth depth data, for example, the missing opposite teeth depth data can be predicted by inputting the tooth site depth data and the surrounding teeth depth data into an AI model.

[0044] In particular, when the target prepared tooth or the abutment at the target tooth site is missing or the shape of the target prepared tooth or the abutment is too special, the tooth site depth data can be the fixed depth data of the target tooth site determined in advance, or the mean value of the depth data of the target tooth site, which is not limited here.

[0045] When step S3 is performed, the crown three-dimensional data of the target tooth site is generated by using the crown depth data of the target tooth site, i.e. the depth data of the crown of the target tooth site. Here, the crown three-dimensional data of the target tooth site can include the outer surface three-dimensional data and / or the inner surface three-dimensional data of the crown of the target tooth site, i.e. the crown three-dimensional data of the target tooth site can only include the outer surface three-dimensional data of the crown of the target tooth site, or only include the inner surface three-dimensional data of the crown of the target tooth site, or include both the outer surface three-dimensional data and the inner surface three-dimensional data of the crown of the target tooth site.

[0046] The outer surface three-dimensional data is a three-dimensional model or a three-dimensional point cloud of the outer surface of the dental crown of the target tooth site, which can be obtained by performing spherical depth back projection on the dental crown depth data of the target tooth site. The inner surface three-dimensional data is a three-dimensional model or a three-dimensional point cloud of the inner surface of the dental crown of the target tooth site, which can be directly obtained by taking the outer surface three-dimensional data of the target tooth site as the inner surface three-dimensional data of the dental crown of the target tooth site.

[0047] When applied to a dental restoration scene, the dental crown three-dimensional data of the target tooth site can be used to manufacture or 3D print the dental crown of the target tooth site. When applied to a dental implant scene, the dental crown three-dimensional data of the target tooth site can be used to design a threaded hole for the dental crown.

[0048] It can be understood that the spherical depth back projection is the inverse process of the spherical depth projection, i.e., the process of converting the depth data to three-dimensional data. In general, a fixed point selected in the spherical depth projection can be determined first, and then each data point in the three-dimensional data can be determined according to the continuous direction and distance corresponding to each data point in the depth data.

[0049] If there is only the adjacent tooth and no opposite tooth around the tooth body, and the input of the dental crown depth data prediction model also has no adjacent tooth depth data, the adjacent tooth can be used to constrain the width of the dental crown of the target tooth site. Therefore, the dental crown width data can be introduced when performing the spherical depth back projection on the dental crown depth data of the target tooth site, so that the obtained dental crown three-dimensional data of the target tooth site meets the requirement of the dental crown width. The dental crown width data can be a predetermined mean value of the dental crown width of the target tooth site.

[0050] If there is only the opposite tooth and no adjacent tooth around the tooth body, and the input of the dental crown depth data prediction model also has no opposite tooth depth data, the opposite tooth can be used to constrain the height of the dental crown of the target tooth site. Therefore, the dental crown height data can be introduced when performing the spherical depth back projection on the dental crown depth data of the target tooth site, so that the obtained dental crown three-dimensional data of the target tooth site meets the requirement of the dental crown height. The dental crown height data can be a predetermined mean value of the dental crown height of the target tooth site.

[0051] If the target tooth site is missing or the shape of the target tooth site is too special, the predetermined dental crown fixed height data and width data of the target tooth site can be introduced when performing the spherical depth back projection on the dental crown depth data of the target tooth site, which is not limited here.

[0052] In addition, the crown depth data of the target tooth site can be screened first, and data points with large distance values are filtered out from the crown depth data of the target tooth site, and the three-dimensional crown data of the target tooth site is obtained by spherical depth back-projection on the screening result, which is not specifically limited here.

[0053] The three-dimensional crown data generation method provided in the embodiments of the present application can obtain tooth site depth data and surrounding tooth depth data by spherical depth projection on the three-dimensional tooth site data and the three-dimensional surrounding tooth data of the target tooth site, which is more accurate and reliable than other ways of obtaining depth data. Moreover, the method determines the crown depth data of the target tooth site by using the crown depth data prediction model, which can improve the prediction efficiency and accuracy of the crown depth data. Finally, the method generates the three-dimensional crown data of the target tooth site by using the crown depth data, which can improve the generation efficiency and accuracy of the three-dimensional crown data, realize the automatic generation of the three-dimensional crown data of the target tooth site, and reduce the labor cost caused by generating the three-dimensional crown data.

[0054] In some optional embodiments, the three-dimensional crown data of the target tooth site is generated based on the crown depth data of the target tooth site, including: obtaining three-dimensional tooth site edge data of the target tooth site; correcting the crown depth data of the target tooth site based on the three-dimensional tooth site edge data to obtain corrected crown depth data; and performing spherical depth back-projection on the corrected crown depth data to obtain the three-dimensional crown data of the target tooth site.

[0055] Specifically, when generating the three-dimensional crown data of the target tooth site, the three-dimensional tooth site edge data of the target tooth site can be obtained, which is the three-dimensional data of the edge closed line of the target object at the target tooth site, and can be obtained by preprocessing the three-dimensional crown data of the target tooth site.

[0056] Thereafter, the three-dimensional tooth site edge data can be used to correct the crown depth data of the target tooth site to obtain corrected crown depth data. Since the crown depth data of the target tooth site is two-dimensional data, the three-dimensional tooth site edge data can be first converted into two-dimensional tooth site edge lines, and then the two-dimensional tooth site edge lines are used to correct the crown depth data of the target tooth site. For example, the crown depth data of the target tooth site can be corrected by the area enclosed by the two-dimensional tooth site edge lines in the two-dimensional space, and the corrected crown depth data is obtained. It can be understood that the correction process of the crown depth data of the target tooth site, i.e., the filtering process of the crown depth data of the target tooth site by the area enclosed by the two-dimensional tooth site edge lines in the two-dimensional space, is to filter out data points with large distance values in the crown depth data of the target tooth site.

[0057] Further, by performing spherical depth back-projection on the corrected crown depth data, the obtained crown three-dimensional data of the target tooth site can be more accurate, and the influence of error data points in the crown depth data of the target tooth site on the determination of the crown three-dimensional data of the target tooth site can be reduced.

[0058] In some optional embodiments, the tooth site edge three-dimensional data at least includes one of the maximum circumference data and the cervical margin line data of the target object at the target tooth site. Specifically, the tooth site edge three-dimensional data used in the embodiments of the present application can include the maximum circumference data of the target tooth site, or the cervical margin line data of the target tooth site, or both the maximum circumference data and the cervical margin line data of the target tooth site.

[0059] The maximum circumference data of the target tooth site refers to the three-dimensional data of the edge closed line of the maximum circumference of the target object at the target tooth site in each cross section perpendicular to the tooth height direction. The cervical margin line data of the target tooth site refers to a thin line around the neck of the target object at the target tooth site, which is located at the gum edge and is the boundary line between the crown and the root of the target tooth site.

[0060] The maximum circumference data and the cervical margin line data of the target tooth site can both be obtained by artificial intelligence technology. For example, the tooth site depth data of the target tooth site can be input into a pre-trained edge data prediction model to obtain tooth site edge three-dimensional data output by the edge data prediction model, which at least includes the maximum circumference data and the cervical margin line data of the target tooth site. The edge data prediction model is at least trained by tooth samples carrying maximum circumference data labels and / or cervical margin line data labels.

[0061] In the embodiments of the present application, the content of the tooth site edge three-dimensional data (such as the maximum circumference data and the cervical margin line data) is given, which not only provides a basis for the correction of the crown depth data of the target tooth site, but also improves the flexibility of the correction of the crown depth data of the target tooth site. Moreover, the use of the maximum circumference data of the target tooth site can make the obtained crown of the target tooth site and the size of the target object at the target tooth site more matched. The use of the cervical margin line data of the target tooth site can make the obtained crown of the target tooth site and the target object at the target tooth site more closely fit at the neck.

[0062] In some optional embodiments, based on the tooth site edge three-dimensional data, the crown depth data of the target tooth site is corrected to obtain corrected crown depth data, including: determining a correction mask based on the tooth site edge three-dimensional data; determining the data in the selected area in the correction mask in the crown depth data of the target tooth site as the corrected crown depth data.

[0063] Specifically, when correcting the crown depth data of the target tooth site, a correction mask can be determined by using the tooth site edge three-dimensional data. The correction mask can be a two-dimensional image, and the size of the correction mask can be the same as the size of the region of the crown depth data of the target tooth site. The correction mask can be obtained by converting the tooth site edge three-dimensional data into tooth site edge two-dimensional lines and constructing the correction mask by using the tooth site edge two-dimensional lines.

[0064] The selected region of the correction mask can be a transparent region surrounded by the tooth site edge two-dimensional lines, and the region of the correction mask other than the selected region can be a non-transparent region, for example, a full black region.

[0065] After the correction mask is determined, the correction mask can be overlaid on the crown depth data of the target tooth site, the data in the crown depth data of the target tooth site in the selected region of the correction mask is screened out, and the data is determined as the corrected crown depth data.

[0066] In the embodiments of the present application, the correction mask corresponding to the tooth site edge three-dimensional data is used to screen the crown depth data of the target tooth site, which can filter out the noise data in the crown depth data of the target tooth site, so that the corrected crown depth data is more accurate, and the accuracy of the crown three-dimensional data of the target tooth site can be further improved.

[0067] In some optional embodiments, the spherical depth projection is performed on the tooth site three-dimensional data and the surrounding tooth three-dimensional data to obtain tooth site depth data and surrounding tooth depth data, including: determining a common sphere center; based on the common sphere center, performing spherical depth projection on the tooth site three-dimensional data and the surrounding tooth three-dimensional data to obtain the tooth site depth data and the surrounding tooth depth data.

[0068] Specifically, the sphere center is determined due to the implementation requirements of the spherical depth projection, and in the embodiments of the present application, the common sphere center can be determined first, that is, the same sphere center is used for spherical depth projection of different depth data. The position of the common sphere center can be set according to requirements, for example, the position of the common sphere center can be determined by the position information of the cervical line data of the target tooth site. The position determination standard of the common sphere center can be that the common sphere center is on the same vertical line as the center point of the target tooth site and slightly lower than the minimum value of the cervical line data of the target tooth site.

[0069] Thereafter, the common sphere center can be used to perform spherical depth projection on the tooth site three-dimensional data and the surrounding tooth three-dimensional data to obtain the tooth site depth data and the surrounding tooth depth data. For example, the tooth site depth data and the surrounding tooth depth data can be determined according to the distance from the common sphere center to each data point in the tooth site three-dimensional data and the surrounding tooth three-dimensional data, and the direction of the connecting line of the common sphere center and each data point in the tooth site three-dimensional data and the surrounding tooth three-dimensional data.

[0070] In the embodiment of the present application, the tooth site three-dimensional data and the surrounding tooth three-dimensional data are projected on a spherical surface with a common sphere center, so that the obtained surrounding tooth depth data and the tooth site depth data can be quickly and accurately combined and used together to determine the crown depth data of the target tooth site.

[0071] In some optional embodiments, the tooth site depth data and the surrounding tooth depth data are represented based on depth images; and the spherical surface depth projection on the tooth site three-dimensional data and the surrounding tooth three-dimensional data to obtain the tooth site depth data and the surrounding tooth depth data comprises: constructing a three-dimensional rectangular coordinate system; and for any one of the tooth site three-dimensional data and the surrounding tooth three-dimensional data, performing the following operations: sampling a plurality of first rays with the origin of the three-dimensional rectangular coordinate system as a fixed point, and determining the position information of each pixel point in the depth image corresponding to the object and having a mapping relationship with each first ray based on the unit direction of each first ray; and determining the distance information from the intersection point of each first ray and the three-dimensional data of the object to the origin, and determining the pixel value of each pixel point in the depth image corresponding to the object and having a mapping relationship with each first ray based on the distance information.

[0072] Specifically, in the embodiment of the present application, the tooth site depth data and the surrounding tooth depth data can both be represented in the form of depth images, so that when the tooth site three-dimensional data and the surrounding tooth three-dimensional data are projected on a spherical surface, a three-dimensional rectangular coordinate system can be constructed first. The construction of the three-dimensional rectangular coordinate system can be determined according to requirements, and only the origin and three coordinate axes thereof need to be determined. The three coordinate axes include a horizontal axis (i.e., an X axis), a vertical axis (i.e., a Y axis), and a vertical axis (i.e., a Z axis).

[0073] To save the calculation cost, the construction standard of the three-dimensional rectangular coordinate system can be that the vertical axis of the three-dimensional rectangular coordinate system is perpendicular to the intraoral occlusal plane, and the three-dimensional data of each type of object is in the positive direction of the vertical axis. Here, each type of object can include a target object such as a target tooth preparation or an abutment at a target tooth site, and surrounding teeth such as adjacent teeth.

[0074] Thereafter, a spherical surface with the origin of the three-dimensional rectangular coordinate system as a sphere center can be determined, and a plurality of rays on the spherical surface can be obtained from the origin. In particular, if the three-dimensional data of each type of object is in the positive direction of the three-dimensional rectangular coordinate system, a plurality of rays on a half-spherical surface with the origin as a sphere center and facing the positive direction of the vertical axis can be determined.

[0075] For any one of the target object or the surrounding tooth, a plurality of first rays with the origin as the fixed point can be sampled, and the position information of each pixel point in the depth image corresponding to the object and having the mapping relationship with each first ray can be determined by using the unit direction of each first ray.

[0076] The process of spherical depth projection can be understood as a process of determining the pixel value of each pixel point in the depth image corresponding to each object by using the three-dimensional data in the three-dimensional rectangular coordinate system. In the process of spherical depth projection, each pixel point in the depth image corresponding to each object has a mapping relationship with each first ray corresponding to the object. For any first ray, the unit direction of the first ray is (Rx, Ry, Rz), and the coordinate of the pixel point in the depth image corresponding to the object and having the mapping relationship with the first ray is (Px, Py). The mapping relationship between the first ray and the pixel point can be expressed as:

[0077] wherein H is the size of the depth image, and the depth image is a square, so the length and width of the depth image are both H.

[0078] According to the unit direction of the first ray, the position information of the pixel point in the depth image and having the mapping relationship with the first ray can be determined by using the above mapping relationship, and vice versa. It should be noted that in the mapping relationship satisfying the above formula, not all pixel points in the depth image can be mapped to the same first ray.

[0079] Thereafter, the intersection point of each first ray and the three-dimensional data of the object can be determined. Each first ray and the three-dimensional data of the object can have no intersection point, one intersection point or multiple intersection points.

[0080] The distance information between each intersection point and the origin of the three-dimensional rectangular coordinate system can be determined, and the distance information can be calculated by using the coordinates of the intersection point and the coordinates of the origin in the three-dimensional rectangular coordinate system.

[0081] Finally, by using the calculated distance information, the pixel value of each pixel point in the depth image corresponding to the object and having the mapping relationship with each first ray can be determined, i.e. the calculated distance information corresponding to each first ray can be used as the pixel value of the pixel point having the mapping relationship with the first ray.

[0082] As shown in FIG. 2, it is a schematic diagram of the dental site three-dimensional data in the three-dimensional rectangular coordinate system. The dental site depth data obtained by the spherical depth projection of the dental site three-dimensional data can be represented as the dental site depth image as shown in FIG. 3.

[0083] In the embodiment of the present application, by converting each data point in the three-dimensional data of each object in the three-dimensional rectangular coordinate system to the pixel value of each pixel point in the depth image in the two-dimensional space, the spherical depth projection can be realized to improve the accuracy of the depth image.

[0084] In some optional embodiments, the three-dimensional rectangular coordinate system is constructed, including: determining the coordinate axis direction of the three-dimensional rectangular coordinate system based on the dental site three-dimensional data and the surrounding dental three-dimensional data, or based on the intraoral tooth three-dimensional data where the target dental site is located; and determining the origin of the three-dimensional rectangular coordinate system based on the data range of the cervical margin line data of the target dental site in the vertical axis direction of the three-dimensional rectangular coordinate system.

[0085] Specifically, when constructing the three-dimensional rectangular coordinate system, if the intraoral teeth where the target dental site is located are missing more, the coordinate axis direction of the three-dimensional rectangular coordinate system can be determined by using the dental site three-dimensional data and the surrounding dental three-dimensional data. If the intraoral teeth where the target dental site is located are missing less, the coordinate axis direction of the three-dimensional rectangular coordinate system can be determined by using the intraoral tooth three-dimensional data where the target dental site is located.

[0086] For example, the intraoral occlusal plane can be determined by using the dental site three-dimensional data and the surrounding dental three-dimensional data, or the intraoral tooth three-dimensional data, and then the normal direction of the intraoral occlusal plane is taken as the vertical axis direction of the three-dimensional rectangular coordinate system, and the horizontal axis direction and the longitudinal axis direction of the three-dimensional rectangular coordinate system are selected in the intraoral occlusal plane. The determination of the occlusal plane by using the full-mouth tooth three-dimensional data with at least one occlusal state can simplify the step of determining the coordinate system and accelerate the calculation efficiency.

[0087] Thereafter, the origin of the three-dimensional rectangular coordinate system is determined by using the data range of the cervical margin line data of the target dental site in the vertical axis direction of the three-dimensional rectangular coordinate system, and taking the dental site three-dimensional data in the positive direction of the vertical axis as the standard. For example, the origin can be set at a position slightly lower than the lowest point of the data range of the cervical margin line data of the target dental site in the vertical axis direction of the three-dimensional rectangular coordinate system.

[0088] In the embodiment of the present application, the coordinate axis direction of the three-dimensional rectangular coordinate system is determined by using the dental site three-dimensional data and the surrounding dental three-dimensional data, which can improve the construction efficiency of the three-dimensional rectangular coordinate system and facilitate the unified calculation of the data.

[0089] In some optional embodiments, the surrounding tooth three-dimensional data comprises the opposite tooth three-dimensional data of the target tooth site and the adjacent tooth three-dimensional data of the target tooth site; and the coordinate axis directions of the three-dimensional rectangular coordinate system are determined based on the tooth site three-dimensional data and the surrounding tooth three-dimensional data, comprising: determining the center point of the target tooth site based on the tooth site three-dimensional data, and determining the center points of each surrounding tooth of the target tooth site based on the surrounding tooth three-dimensional data; determining a tooth fitting plane based on the center point of the target tooth site and the center points of each surrounding tooth, and determining the normal direction of the tooth fitting plane as the horizontal axis direction of the three-dimensional rectangular coordinate system; determining at least two objects in the same dental arch from the target tooth site and each surrounding tooth, and determining the line direction of the center points of the at least two objects as the vertical axis direction of the three-dimensional rectangular coordinate system; and determining the vertical axis direction of the three-dimensional rectangular coordinate system based on the horizontal axis direction and the vertical axis direction.

[0090] Specifically, in the case where the surrounding tooth comprises the adjacent tooth and the opposite tooth of the target tooth site, i.e., the surrounding tooth three-dimensional data comprises the opposite tooth three-dimensional data of the target tooth site and the adjacent tooth three-dimensional data of the target tooth site, when determining the coordinate axis directions of the three-dimensional rectangular coordinate system, the center point of the target tooth site can be determined first by using the tooth site three-dimensional data. The center point of the target tooth site refers to the center point of the target object at the target tooth site, which can be extracted by AI technology by extracting the feature points of the tooth site three-dimensional data. For example, the tooth site three-dimensional data can be input into a feature point extraction model to obtain the feature points of the tooth site three-dimensional data output by the feature point extraction model. The feature point extraction model can be obtained by training the three-dimensional data of the tooth site sample carrying the feature point label.

[0091] Then, the center point of the target tooth site is obtained by the difference between the feature points.

[0092] Similarly, the center points of each surrounding tooth of the target tooth site, i.e., the center points of each adjacent tooth and the center points of each opposite tooth of the target tooth site, can be determined by using the surrounding tooth three-dimensional data. For example, the surrounding tooth three-dimensional data can also be input into a feature point extraction model to obtain the feature points of the surrounding tooth three-dimensional data output by the feature point extraction model. Then, the center points of the surrounding tooth are obtained by the difference between the feature points.

[0093] Thereafter, the tooth fitting plane can be determined by the principle of determining a plane by three points by using the center point of the target tooth site and the center points of each surrounding tooth. Thereafter, the normal direction of the tooth fitting plane can be determined as the horizontal axis direction of the three-dimensional rectangular coordinate system.

[0094] Thereafter, at least two objects in the same dental arch can be determined from the target tooth site and each surrounding tooth, for example, the target object and its adjacent tooth, or the opposite tooth of the target object and the adjacent tooth of the opposite tooth. The line direction of the center points of the at least two objects in the same dental arch is determined as the vertical axis direction of the three-dimensional rectangular coordinate system.

[0095] At this time, the normal direction of the dental fitting plane and the direction of the connecting line of the center points of at least two objects in the same dental arch, that is, the horizontal axis direction and the vertical axis direction of the three-dimensional rectangular coordinate system, can be used to construct the occlusal plane in the mouth.

[0096] The vertical axis direction of the three-dimensional rectangular coordinate system is determined by using the horizontal axis direction and the vertical axis direction of the three-dimensional rectangular coordinate system. That is, the direction perpendicular to the horizontal axis direction and the vertical axis direction, that is, the normal direction of the occlusal plane in the mouth, is taken as the vertical axis direction.

[0097] In the embodiments of the present application, the coordinate axis direction of the three-dimensional rectangular coordinate system is determined by the center points, which can simplify the construction process of the coordinate system and improve the generation efficiency of the crown three-dimensional data.

[0098] In some optional embodiments, the surrounding dental three-dimensional data includes the opposite tooth three-dimensional data of the target tooth site and the adjacent tooth three-dimensional data of the target tooth site; and the surrounding dental depth data is determined by performing spherical depth projection on the opposite tooth three-dimensional data and the adjacent tooth three-dimensional data to obtain the opposite tooth depth data of the target tooth site and the adjacent tooth depth data of the target tooth site, respectively.

[0099] Specifically, the surrounding dental of the target tooth site can include the opposite tooth of the target tooth site and the adjacent tooth of the target tooth site. Therefore, the surrounding dental three-dimensional data can include the opposite tooth three-dimensional data of the target tooth site and the adjacent tooth three-dimensional data of the target tooth site.

[0100] On this basis, when determining the surrounding dental depth data, the opposite tooth three-dimensional data and the adjacent tooth three-dimensional data can be subjected to spherical depth projection to obtain the opposite tooth depth data of the target tooth site and the adjacent tooth depth data of the target tooth site, respectively. For example, the opposite tooth three-dimensional data can be subjected to spherical depth projection to obtain the opposite tooth depth data of the target tooth site, the adjacent tooth three-dimensional data can be subjected to spherical depth projection to obtain the adjacent tooth depth data of the target tooth site, or the opposite tooth three-dimensional data and the adjacent tooth three-dimensional data can be subjected to spherical depth projection to obtain the opposite tooth depth data of the target tooth site and the adjacent tooth depth data of the target tooth site, respectively.

[0101] As shown in FIG. 4, it is a schematic diagram of the opposite tooth three-dimensional data of the target tooth site in the three-dimensional rectangular coordinate system. The opposite tooth depth data obtained by performing spherical depth projection on the opposite tooth three-dimensional data can be represented as the opposite tooth depth image shown in FIG. 5.

[0102] As can be seen from FIGS. 4 and 5, the opposite tooth of the target tooth site includes the directly opposite tooth and the two adjacent teeth on the left and right sides of the directly opposite tooth.

[0103] As shown in FIG. 6, it is a schematic diagram of the three-dimensional data of the adjacent teeth of the target tooth position in the three-dimensional rectangular coordinate system. The adjacent tooth depth data obtained by spherical depth projection of the three-dimensional data of the adjacent teeth can be represented as the adjacent tooth depth image shown in FIG. 7.

[0104] As can be seen from FIG. 6 and FIG. 7, the adjacent teeth of the target tooth position include one adjacent tooth on the left side of the target tooth position and one adjacent tooth on the right side of the target tooth position.

[0105] In the process of determining the crown depth data of the target tooth position by using the crown depth data prediction model, the tooth position depth image, the tooth depth image and the adjacent tooth depth image of the target tooth position can be superimposed by channel, and then the superimposed result is input into the crown depth data prediction model to obtain the crown depth image of the target tooth position output by the crown depth data prediction model. As shown in FIG. 8, it is a schematic diagram of the crown depth image of the target tooth position.

[0106] In the embodiment of the present application, the types of the surrounding teeth of the target tooth position are specifically refined, which can make the crown three-dimensional data of the target tooth position more accurate.

[0107] In some optional embodiments, based on the intraoral tooth three-dimensional data of the target tooth position, the coordinate axis direction of the three-dimensional rectangular coordinate system is determined, including: determining the occlusal plane of the intraoral teeth based on the intraoral tooth three-dimensional data; determining the vertical axis direction of the three-dimensional rectangular coordinate system based on the occlusal plane of the intraoral teeth, and determining the tooth fitting plane, and determining the normal direction of the tooth fitting plane as the horizontal axis direction of the three-dimensional rectangular coordinate system; determining the longitudinal axis direction of the three-dimensional rectangular coordinate system based on the horizontal axis direction and the vertical axis direction.

[0108] Specifically, in the process of determining the coordinate axis direction of the three-dimensional rectangular coordinate system by using the intraoral tooth three-dimensional data of the target tooth position, the occlusal plane of the intraoral teeth can be determined by using the intraoral tooth three-dimensional data first. The intraoral tooth three-dimensional data can be the three-dimensional data of all teeth obtained under the intraoral occlusion condition. The occlusal plane of the intraoral teeth can be obtained by fitting the contact positions of the upper jaw teeth and the lower jaw teeth in the three-dimensional data of all teeth.

[0109] Then, the vertical axis direction of the three-dimensional rectangular coordinate system can be determined by using the occlusal plane of the intraoral teeth. Here, the normal of the occlusal plane of the intraoral teeth can be directly taken as the vertical axis direction of the three-dimensional rectangular coordinate system.

[0110] Further, the normal plane of the occlusal plane of the intraoral teeth can be taken as the tooth fitting plane, or the tooth fitting plane can be determined by the center point of the target tooth position and the center points of the surrounding teeth, which is not limited here. The normal direction of the tooth fitting plane is the horizontal axis direction of the three-dimensional rectangular coordinate system.

[0111] Finally, the vertical relationship of the coordinate axes of the three-dimensional rectangular coordinate system can be used to determine the longitudinal axis direction of the three-dimensional rectangular coordinate system.

[0112] In the embodiment of the present application, the three-dimensional data of the teeth in the mouth can be used to quickly and concisely determine the coordinate axis direction of the three-dimensional rectangular coordinate system.

[0113] In some optional embodiments, the vertical axis direction is from the jaw where the target tooth site is located to the opposite jaw, and the position information of the origin in the vertical axis direction is less than the minimum position information of the neck line data of the target tooth site in the vertical axis direction.

[0114] Specifically, the vertical axis direction of the three-dimensional rectangular coordinate system can be positive from the jaw where the target tooth site is located to the opposite jaw.

[0115] Meanwhile, the position information of the origin of the three-dimensional rectangular coordinate system in the vertical axis direction can be less than the minimum position information of the neck line data of the target tooth site in the vertical axis direction, so that the vertical coordinates of each data point in the three-dimensional data of any type of object are greater than 0, facilitating subsequent data calculation.

[0116] In some optional embodiments, based on the distance information, the pixel values of the pixel points in the depth image corresponding to each first ray and having a mapping relationship with the first ray are determined, including: for any first ray, if the intersection of the first ray and the three-dimensional data of the object includes multiple, the minimum value of the distance information from the multiple intersection points to the origin is determined, and the minimum value is taken as the pixel value of the pixel point in the depth image corresponding to the first ray and having a mapping relationship with the first ray.

[0117] Specifically, when the distance information is used to determine the pixel values of the pixel points in the depth image corresponding to each first ray and having a mapping relationship with the first ray, the same operation can be performed for any first ray, that is, to determine whether the intersection of the first ray and the three-dimensional data of the object includes multiple, if the object includes multiple, the three-dimensional data of each object in the object can intersect with the first ray, that is, the intersection of the first ray and the three-dimensional data of the object can include multiple, the distance information between the multiple intersection points and the origin of the three-dimensional rectangular coordinate system can be determined, and the minimum value can be selected as the pixel value of the pixel point in the depth image corresponding to the first ray and having a mapping relationship with the first ray, so that the situation that one pixel point in the depth image has a mapping relationship with multiple first rays and has multiple pixel values can be avoided. Moreover, selecting the minimum value as the pixel value of the pixel point having a mapping relationship with the first ray can make the obtained crown depth data of the target tooth site more accurate.

[0118] In some optional embodiments, the modified mask is determined based on the tooth position edge three-dimensional data, including: performing spherical projection on the tooth position edge three-dimensional data to obtain tooth position edge two-dimensional lines; and determining the modified mask based on the tooth position edge two-dimensional lines.

[0119] Specifically, when determining the modified mask, the tooth position edge three-dimensional data can be first projected on a sphere to obtain tooth position edge two-dimensional lines. The tooth position edge two-dimensional lines refer to two-dimensional data of the edge of the target object at the target tooth position, which can include at least one of the maximum circumference line and the neck line of the target tooth position.

[0120] The spherical projection refers to a process of converting three-dimensional data to two-dimensional data, which can generally first select a fixed point, and then convert each data point in the three-dimensional data to a data point in the two-dimensional data according to the direction of the connecting line between the fixed point and each data point in the three-dimensional data. Each data point in the two-dimensional data can represent the direction of the connecting line between the fixed point and each data point in the three-dimensional data. Here, each data point in the two-dimensional data can be each pixel point in a two-dimensional image. The fixed point can be the same as the fixed point used in the spherical depth projection.

[0121] When the tooth position edge three-dimensional data includes both the maximum circumference data and the neck line data of the target tooth position, the maximum circumference data and the neck line data can be respectively projected on a sphere to obtain the maximum circumference line and the neck line.

[0122] Finally, when the tooth position edge three-dimensional data includes the maximum circumference data of the target tooth position, the tooth position edge two-dimensional lines can include the maximum circumference line, and the modified mask can be determined using the maximum circumference line.

[0123] When the tooth position edge three-dimensional data includes the neck line data of the target tooth position, the tooth position edge two-dimensional lines can include the neck line, and the modified mask can be determined using the neck line.

[0124] When the tooth position edge three-dimensional data includes both the maximum circumference data and the neck line data of the target tooth position, the tooth position edge two-dimensional lines can include the maximum circumference line and the neck line, and the modified mask can be determined using the maximum circumference line and the neck line. For example, the modified mask can be determined by selecting the line with a larger enclosed area from the maximum circumference line and the neck line.

[0125] In the embodiments of the present application, by performing spherical projection on the tooth position edge three-dimensional data and determining the modified mask using the obtained tooth position edge two-dimensional lines, the accuracy of the modified mask can be improved, and the noise data in the crown depth data of the target tooth position can be accurately filtered out.

[0126] In some optional embodiments, the tooth position edge three-dimensional data comprises a plurality of line segments; the spherical projection of the tooth position edge three-dimensional data to obtain the tooth position edge two-dimensional line comprises: determining a second ray from the origin of the three-dimensional rectangular coordinate system of the target tooth position to the end point of each line segment in the plurality of line segments, and determining the position information of each pixel point in the two-dimensional image having a mapping relationship with the second ray based on the unit direction of the second ray; connecting each pixel point in the two-dimensional image according to the connection relationship between the end points of each line segment in the tooth position edge three-dimensional data to obtain the tooth position edge two-dimensional line; wherein the pixel value of the pixel point in the two-dimensional image located within a preset range around the tooth position edge two-dimensional line is set to 1, and the pixel value of the pixel point outside the preset range is set to 0.

[0127] Specifically, the tooth position edge three-dimensional data can be composed of a plurality of line segments, so when the spherical projection of the tooth position edge three-dimensional data is performed, the second ray from the origin of the three-dimensional rectangular coordinate system of the target tooth position to the end point of each line segment can be determined first. Then the position information of each pixel point in the two-dimensional image having a mapping relationship with the second ray is determined by using the unit direction of the second ray. In the spherical projection process, there is a mapping relationship between each pixel point in the two-dimensional image and the second ray. The mapping relationship can be represented by the same formula as the mapping relationship between the first ray and the pixel point, that is, the formula of Px and Py as described above.

[0128] After that, each pixel point in the two-dimensional image is connected according to the connection relationship between the end points of each line segment in the tooth position edge three-dimensional data, and the tooth position edge two-dimensional line can be obtained.

[0129] Finally, the pixel value of the pixel point in the two-dimensional image located within a preset range around the tooth position edge two-dimensional line can be set to 1, and the pixel value of the remaining pixel points in the two-dimensional image can be set to 0. It can be understood that the preset range can be set as needed, for example, it can be the area formed by the tooth position edge two-dimensional line and at least one pixel point around it.

[0130] In the embodiments of the present application, the spherical projection method of the tooth position edge three-dimensional data is provided, which is simple and easy to use, and can improve the calculation efficiency.

[0131] In some optional embodiments, the corrected crown depth data is based on a corrected crown depth image representation; the spherical depth back projection is performed on the corrected crown depth data to obtain the crown three-dimensional data of the target tooth site, including: based on the position information of the target pixel point with a non-zero pixel value on the corrected crown depth image, determining a plurality of third rays with the origin of the three-dimensional rectangular coordinate system of the target tooth site as a fixed point and having a mapping relationship with the target pixel point; for any third ray, determining a three-dimensional point in the unit direction of the third ray, and the distance information between the three-dimensional point and the origin is the pixel value of the pixel point having a mapping relationship with the third ray; based on the three-dimensional point corresponding to the target pixel point and the three-dimensional point corresponding to the designated neighborhood pixel point of the target pixel point, determining the crown three-dimensional data of the target tooth site; the designated neighborhood pixel point is a non-zero pixel value pixel point in the neighborhood range of the target pixel point.

[0132] Specifically, in the embodiments of the present application, the depth data can all be represented as depth images, i.e., the corrected crown depth data can be represented as a corrected crown depth image. When performing spherical depth back projection on the corrected crown depth data, since spherical depth back projection is the inverse process of spherical depth projection, the position information of the target pixel point with a non-zero pixel value on the corrected crown depth image can be used to determine a plurality of third rays with the origin of the three-dimensional rectangular coordinate system of the target tooth site as a fixed point and having a mapping relationship with the target pixel point, by means of the mapping relationship between the pixel point and the first ray in the spherical depth projection process.

[0133] Thereafter, for any third ray, a three-dimensional point having the distance information between the three-dimensional rectangular coordinate system of the target tooth site and the origin in the unit direction of the third ray can be determined according to the pixel value of the pixel point having a mapping relationship with the third ray.

[0134] Thereafter, the three-dimensional point corresponding to the target pixel point and the three-dimensional point corresponding to the neighborhood pixel point of the target pixel point can be used to determine the crown three-dimensional data of the target tooth site. For example, the three-dimensional point corresponding to the target pixel point and the three-dimensional point corresponding to the neighborhood pixel point of the target pixel point can be connected to form a patch. All the patches corresponding to the target pixel points can constitute the crown three-dimensional data of the target tooth site.

[0135] It can be understood that the neighborhood pixel point can include the right side adjacent non-zero pixel value pixel point and the upper side adjacent non-zero pixel value pixel point of the target pixel point, and can also include the left side adjacent non-zero pixel value pixel point and the lower side adjacent non-zero pixel value pixel point of the target pixel point.

[0136] In the embodiments of the present application, the spherical depth back projection method is simple and easy to implement, and can improve the calculation efficiency.

[0137] In some optional embodiments, the dental crown depth data prediction model is trained based on the depth data of the dental site sample, the surrounding dental depth data of the dental site sample, and the dental crown depth data label of the dental site sample.

[0138] Specifically, in the training process of the dental crown depth data prediction model, the depth data of the dental site sample and the surrounding dental depth data of the dental site sample can be input into an initial prediction model to obtain a prediction result output by the initial prediction model, then a loss function value is calculated according to the prediction result and the dental crown depth data label of the dental site sample, and finally the structure parameters of the initial prediction model are updated according to the loss function value; the above input process and calculation process are iteratively performed until the loss function converges or reaches a preset iteration number, and the dental crown depth data prediction model is obtained.

[0139] It can be understood that the initial prediction model can be a deep learning model or any other type of machine learning model.

[0140] In the embodiments of the present application, the dental crown depth data prediction model is obtained by model training, which can enable the dental crown depth data prediction model to learn the ability to generate dental crown depth data, and thus the dental crown depth data of the target dental site can be quickly generated through the dental crown depth data prediction model.

[0141] As shown in FIG. 9, it is a schematic diagram of the dental site edge three-dimensional data of the target dental site in a three-dimensional rectangular coordinate system. The dental site edge two-dimensional line obtained by spherical projection of the dental site edge three-dimensional data is shown in FIG. 10. The correction mask determined according to the dental site edge two-dimensional line is shown in FIG. 11.

[0142] The data in the selected area within the correction mask in the dental crown depth data of the target dental site is determined as the corrected dental crown depth data, and the corrected dental crown depth data is subjected to spherical depth back-projection to obtain the dental crown three-dimensional data of the target dental site. The process is shown in FIG. 12.

[0143] As shown in FIG. 13, if the target dental site is the dental site of the third tooth on the left side of the upper jaw, the three-dimensional data of the upper jaw before the target dental site is determined (i.e., the pre-design upper jaw), the three-dimensional data of the lower jaw before the target dental site is determined (i.e., the pre-design lower jaw), and the three-dimensional data of the upper jaw after the target dental site is determined (i.e., the post-design upper jaw) are shown in FIG. 13.

[0144] In summary, in the embodiment of the present application, the target tooth position and its adjacent teeth and opposite teeth are expressed by a single depth image through spherical depth projection technology, so that the prediction model for the depth image can be fully utilized to reduce the calculation loss. The method has good robustness for different oral environments and different positions of the affected teeth. Moreover, in the embodiment of the present application, the predicted depth image is subjected to spherical depth back projection to directly obtain the crown three-dimensional data of the target tooth position, without the need for complex post-processing steps, which is simple, direct and efficient. In addition, in the embodiment of the present application, the prediction model can be used to realize pixel-level prediction of the crown depth data of the target tooth position, which is equivalent to predicting the vertex position of the crown three-dimensional data of the target tooth position in the order of millions, thereby ensuring the detail retention capability of the generated crown. Compared with the method of manually designing a crown, the speed of the method is greatly improved, and the method can complete the design of a crown in a few seconds on a general personal computer.

[0145] As shown in FIG. 14, the embodiment of the present application further provides a crown three-dimensional data generation device, which comprises: an acquisition module 141 configured to acquire tooth position three-dimensional data of a target tooth position and surrounding tooth three-dimensional data of the target tooth position, and perform spherical depth projection on the tooth position three-dimensional data and the surrounding tooth three-dimensional data to obtain tooth position depth data and surrounding tooth depth data; a prediction module 142 configured to determine the crown depth data of the target tooth position by applying a crown depth data prediction model based on the tooth position depth data and the surrounding tooth depth data; and a generation module 143 configured to generate the crown three-dimensional data of the target tooth position based on the crown depth data of the target tooth position.

[0146] In some optional embodiments, the generation module of the crown three-dimensional data generation device provided in the embodiment of the present application is specifically configured to: acquire tooth edge three-dimensional data of the target tooth position; the tooth edge three-dimensional data at least includes one of the maximum circumference data and the cervical margin line data of the target tooth position; correct the crown depth data of the target tooth position based on the tooth edge three-dimensional data to obtain corrected crown depth data; and perform spherical depth back projection on the corrected crown depth data to obtain the crown three-dimensional data of the target tooth position.

[0147] In some optional embodiments, the generation module of the crown three-dimensional data generation device provided in the embodiment of the present application is specifically configured to: determine a correction mask based on the tooth edge three-dimensional data; and determine the data in the selected area of the correction mask in the crown depth data of the target tooth position as the corrected crown depth data.

[0148] In some optional embodiments, the crown three-dimensional data generation apparatus provided in the embodiments of the present application, the acquisition module is specifically configured to: determine a common sphere center; perform spherical depth projection on the tooth site three-dimensional data and the surrounding tooth three-dimensional data based on the common sphere center to obtain tooth site depth data and surrounding tooth depth data.

[0149] In some optional embodiments, the crown three-dimensional data generation apparatus provided in the embodiments of the present application, the tooth site depth data and the surrounding tooth depth data are represented based on depth images; the acquisition module is specifically configured to: construct a three-dimensional rectangular coordinate system; for any one object in the tooth site three-dimensional data and the surrounding tooth three-dimensional data, perform the following operations: sample a plurality of first rays with the origin of the three-dimensional rectangular coordinate system as a fixed point, and determine the position information of each pixel point in the depth image corresponding to the object and having a mapping relationship with each first ray based on the unit direction of each first ray; and determine the distance information of the intersection point of each first ray and the three-dimensional data of the object to the origin, and determine the pixel value of each pixel point in the depth image corresponding to the object and having a mapping relationship with each first ray based on the distance information.

[0150] In some optional embodiments, the crown three-dimensional data generation apparatus provided in the embodiments of the present application, the acquisition module is specifically configured to: determine the coordinate axis direction of the three-dimensional rectangular coordinate system based on the tooth site three-dimensional data and the surrounding tooth three-dimensional data, or based on the intraoral tooth three-dimensional data where the target tooth site is located; determine the origin of the three-dimensional rectangular coordinate system based on the data range of the cervical line data of the target tooth site in the vertical axis direction of the three-dimensional rectangular coordinate system.

[0151] In some optional embodiments, the crown three-dimensional data generation apparatus provided in the embodiments of the present application, the surrounding tooth three-dimensional data includes the opposite tooth three-dimensional data of the target tooth site and the adjacent tooth three-dimensional data of the target tooth site; the acquisition module is specifically configured to: determine the center point of the target tooth site based on the tooth site three-dimensional data, and determine the center point of each surrounding tooth of the target tooth site based on the surrounding tooth three-dimensional data; determine a tooth fitting plane based on the center point of the target tooth site and the center point of each surrounding tooth, and determine the normal direction of the tooth fitting plane as the horizontal axis direction of the three-dimensional rectangular coordinate system; determine at least two objects in the same dental arch in the target tooth site and each surrounding tooth, and determine the line direction of the center points of the at least two objects as the vertical axis direction of the three-dimensional rectangular coordinate system; determine the vertical axis direction of the three-dimensional rectangular coordinate system based on the horizontal axis direction and the vertical axis direction.

[0152] In some optional embodiments, the crown three-dimensional data generation apparatus provided in the embodiments of the present application, the acquisition module is specifically configured to: perform spherical depth projection on the opposite tooth three-dimensional data and the adjacent tooth three-dimensional data to obtain the opposite tooth depth data of the target tooth site and the adjacent tooth depth data of the target tooth site, respectively.

[0153] In some optional embodiments, the crown three-dimensional data generation apparatus provided in the embodiments of the present application, the acquisition module is specifically configured to: determine an intraoral tooth occlusal plane based on the intraoral tooth three-dimensional data; determine a vertical axis direction of a three-dimensional rectangular coordinate system based on the intraoral tooth occlusal plane, and determine a dental fitting plane, and determine a normal direction of the dental fitting plane as a horizontal axis direction of the three-dimensional rectangular coordinate system; and determine a longitudinal axis direction of the three-dimensional rectangular coordinate system based on the horizontal axis direction and the vertical axis direction.

[0154] In some optional embodiments, the crown three-dimensional data generation apparatus provided in the embodiments of the present application, the vertical axis direction is from the jaw where the target tooth site is located to the opposite jaw; and the position information of the origin in the vertical axis direction is less than the minimum position information of the cervical margin line data of the target tooth site in the vertical axis direction.

[0155] In some optional embodiments, the crown three-dimensional data generation apparatus provided in the embodiments of the present application, the acquisition module is specifically configured to: for any first ray, if the intersection of the first ray and the three-dimensional data of the object includes multiple, determine the minimum value of the distance information from the multiple intersection points to the origin, and take the minimum value as the pixel value of the pixel point in the depth image corresponding to the object and having a mapping relationship with the first ray.

[0156] In some optional embodiments, the crown three-dimensional data generation apparatus provided in the embodiments of the present application, the generation module is specifically configured to: perform spherical projection on the tooth site edge three-dimensional data to obtain tooth site edge two-dimensional lines; and determine a correction mask based on the tooth site edge two-dimensional lines.

[0157] In some optional embodiments, the crown three-dimensional data generation apparatus provided in the embodiments of the present application, the tooth site edge three-dimensional data includes multiple line segments; and the generation module is specifically configured to: determine a second ray from the origin of the three-dimensional rectangular coordinate system to the end point of each line segment in the multiple line segments, and determine the position information of each pixel point in the two-dimensional image having a mapping relationship with each second ray based on the unit direction of each second ray; connect each pixel point in the two-dimensional image according to the connection relationship between the end points of each line segment in the tooth site edge three-dimensional data to obtain the tooth site edge two-dimensional lines; wherein the pixel value of the pixel point in the two-dimensional image located within a preset range around the tooth site edge two-dimensional lines is set to 1, and the pixel value of the pixel point outside the preset range is set to 0.

[0158] In some optional embodiments, the crown three-dimensional data generation apparatus provided in the embodiments of the present application, the corrected crown depth data is based on a corrected crown depth image; the generation module is specifically configured to: based on position information of a target pixel point with a non-zero pixel value on the corrected crown depth image, determine a plurality of third rays with the origin of the three-dimensional rectangular coordinate system as a fixed point and having a mapping relationship with the target pixel point; for any third ray, determine a three-dimensional point in the unit direction of the third ray, and the distance information between the three-dimensional point and the origin is the pixel value of the pixel point having a mapping relationship with the third ray; based on the three-dimensional point corresponding to the target pixel point and the three-dimensional point corresponding to the designated neighborhood pixel point of the target pixel point, determine the crown three-dimensional data of the target tooth site; the designated neighborhood pixel point is a pixel point with a non-zero pixel value in the neighborhood range of the target pixel point.

[0159] In some optional embodiments, the crown three-dimensional data generation apparatus provided in the embodiments of the present application, the crown depth data prediction model is trained based on the depth data of the tooth site sample, the surrounding tooth depth data of the tooth site sample and the crown depth data label of the tooth site sample.

[0160] Specifically, the roles of each module in the crown three-dimensional data generation apparatus provided in the embodiments of the present application are one-to-one corresponding to the operation processes of each step in the method embodiment, and the effects achieved are consistent. For details, refer to the above embodiments, and the embodiments of the present application will not be repeated here.

[0161] FIG. 15 illustrates an entity structure diagram of an electronic device, as shown in FIG. 15, the electronic device can include: a processor (Processor) 1510, a communication interface (Communications Interface) 1520, a memory (Memory) 1530 and a communication bus 1540, wherein the processor 1510, the communication interface 1520, the memory 1530 complete the communication among each other through the communication bus 1540. The processor 1510 can invoke the logical instructions in the memory 1530 to execute the crown three-dimensional data generation method provided in each of the above embodiments.

[0162] In addition, the logic instructions in the memory 1530 described above can be implemented in the form of software function units and sold or used as independent products, and can be stored in a computer readable storage medium. Based on such understanding, the technical solutions of the present application essentially or the part that contributes to the prior art or part of the technical solutions can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for making a computer device (which can be a personal computer, a server, or a network device, etc.) execute all or part of the steps of the embodiments of the method of the present application. The aforementioned storage medium includes: a U disk, a mobile hard disk, a read-only memory (Read-Only Memory, ROM), a random access memory (Random Access Memory, RAM), a magnetic disk or an optical disk, and various media that can store program codes.

[0163] In another aspect, the present application also provides a computer program product, the computer program product comprising a computer program, the computer program being stored in a non-transitory computer readable storage medium, and the computer program being executable by a processor to cause a computer to perform the crown three-dimensional data generation method provided in the above embodiments.

[0164] In yet another aspect, the present application also provides a non-transitory computer readable storage medium having a computer program stored thereon, the computer program being executable by a processor to cause a computer to perform the crown three-dimensional data generation method provided in the above embodiments.

[0165] The device embodiments described above are only schematic, and the units shown as separate components can or can not be physically separate, and the components shown as units can or can not be physical units, i.e. they can be located in one place or distributed on multiple network units. Part or all of the modules can be selected to achieve the purpose of the present embodiment according to actual needs. Those skilled in the art can understand and implement it without creative labor.

[0166] Those skilled in the art can clearly understand from the above description of the embodiments that each embodiment can be realized by means of software plus necessary universal hardware platforms, and of course can also be realized by hardware. Based on such understanding, the above technical solutions, essentially or in other words, the part that contributes to the prior art, can be embodied in the form of a software product. The computer software product can be stored in a computer readable storage medium, such as a ROM / RAM, a magnetic disk, an optical disk, and the like, and includes a number of instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods of the various embodiments or some parts of the embodiments. Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, rather than limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacements to some technical features; and these modifications or replacements do not cause the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present application. Industrial applicability

[0167] The present disclosure can obtain the tooth site depth data and the surrounding tooth depth data by performing spherical depth projection on the tooth site three-dimensional data of the target tooth site and the surrounding tooth three-dimensional data, which is more accurate and reliable than other ways of obtaining depth data. Moreover, the present disclosure can determine the crown depth data of the target tooth site by using the crown depth data prediction model, which can improve the prediction efficiency and accuracy of the crown depth data. Finally, the present disclosure can generate the crown three-dimensional data of the target tooth site by using the crown depth data, which can improve the generation efficiency and accuracy of the crown three-dimensional data, realize the automatic generation of the crown three-dimensional data, and reduce the labor cost caused by generating the crown three-dimensional data. Overall, the present disclosure can determine each depth data by the spherical depth projection, predict the crown depth data by means of the prediction model, and generate the crown three-dimensional data by the spherical depth inverse projection, which is simple, direct, efficient, and has strong industrial applicability.

Claims

1. A method of generating three-dimensional data of a dental crown, wherein, The method comprises: obtaining tooth site three-dimensional data of a target tooth site and surrounding tooth three-dimensional data of the target tooth site, performing spherical depth projection on the tooth site three-dimensional data and the surrounding tooth three-dimensional data to obtain tooth site depth data and surrounding tooth depth data; based on the tooth site depth data and the surrounding tooth depth data, applying a crown depth data prediction model to determine the crown depth data of the target tooth site; based on the crown depth data of the target tooth site, generating crown three-dimensional data of the target tooth site.

2. The crown three-dimensional data generating method according to claim 1, wherein The method comprises: obtaining tooth site edge three-dimensional data of the target tooth site; the tooth site edge three-dimensional data at least includes one of the maximum circumference data and the neck margin line data of the target tooth site; based on the tooth site edge three-dimensional data, correcting the crown depth data of the target tooth site to obtain corrected crown depth data; performing spherical depth inverse projection on the corrected crown depth data to obtain the crown three-dimensional data of the target tooth site.

3. The crown three-dimensional data generating method according to claim 2, wherein The method comprises: based on the tooth site edge three-dimensional data, determining a correction mask; determining the data in the selected area of the correction mask in the crown depth data of the target tooth site as the corrected crown depth data.

4. The crown three-dimensional data generating method according to claim 1, wherein The method comprises: determining a common sphere center; based on the common sphere center, performing spherical depth projection on the tooth site three-dimensional data and the surrounding tooth three-dimensional data to obtain the tooth site depth data and the surrounding tooth depth data.

5. The crown three-dimensional data generating method of claim 1, wherein, The tooth site depth data and the surrounding tooth depth data are based on depth images; The method comprises: constructing a three-dimensional rectangular coordinate system; for any object in the tooth site three-dimensional data and the surrounding tooth three-dimensional data, performing the following operations: sampling a plurality of first rays with the origin of the three-dimensional rectangular coordinate system as a fixed point, and based on the unit direction of each first ray, determining the position information of each pixel point in the depth image corresponding to the object which has a mapping relationship with each first ray; and determining the distance information from the intersection point of each first ray and the three-dimensional data of the object to the origin, and based on the distance information, determining the pixel value of each pixel point in the depth image corresponding to the object which has a mapping relationship with each first ray.

6. The crown three-dimensional data generating method according to claim 5, wherein The method comprises: based on the tooth site three-dimensional data and the surrounding tooth three-dimensional data, or based on the intraoral tooth three-dimensional data where the target tooth site is located, determining the coordinate axis direction of the three-dimensional rectangular coordinate system; based on the data range of the neck margin line data of the target tooth site in the vertical axis direction of the three-dimensional rectangular coordinate system, determining the origin of the three-dimensional rectangular coordinate system.

7. The crown three-dimensional data generating method according to claim 6, wherein The peripheral tooth three-dimensional data comprises the interproximal tooth three-dimensional data of the target tooth site and the adjacent tooth three-dimensional data of the target tooth site; The coordinate axis direction of the three-dimensional rectangular coordinate system is determined based on the tooth site three-dimensional data and the peripheral tooth three-dimensional data, comprising: The center point of the target tooth site is determined based on the tooth site three-dimensional data, and the center points of the peripheral teeth of the target tooth site are determined based on the peripheral tooth three-dimensional data; The tooth fitting plane is determined based on the center point of the target tooth site and the center points of the peripheral teeth, and the normal direction of the tooth fitting plane is determined as the horizontal axis direction of the three-dimensional rectangular coordinate system; At least two objects in the same dental arch among the target tooth site and the peripheral teeth are determined, and the connecting line direction of the center points of the at least two objects is determined as the vertical axis direction of the three-dimensional rectangular coordinate system; The vertical axis direction of the three-dimensional rectangular coordinate system is determined based on the horizontal axis direction and the vertical axis direction.

8. The crown three-dimensional data generating method according to claim 7, wherein The peripheral tooth depth data is determined by the following method: The spherical depth projection is performed on the interproximal tooth three-dimensional data and the adjacent tooth three-dimensional data to obtain the interproximal tooth depth data of the target tooth site and the adjacent tooth depth data of the target tooth site, respectively.

9. The crown three-dimensional data generating method according to claim 6, wherein The coordinate axis direction of the three-dimensional rectangular coordinate system is determined based on the intraoral tooth three-dimensional data, comprising: The intraoral tooth occlusal plane is determined based on the intraoral tooth three-dimensional data; The vertical axis direction of the three-dimensional rectangular coordinate system is determined based on the horizontal axis direction and the vertical axis direction. The vertical axis direction is from the dental arch where the target tooth site is located to the opposite dental arch; 10. The crown three-dimensional data generating method according to claim 7, wherein The position information of the origin in the vertical axis direction is less than the minimum position information of the cervical line data of the target tooth site in the vertical axis direction. The pixel value of each pixel point in the depth image corresponding to the object and having a mapping relationship with each first ray is determined based on the distance information, comprising:

11. The crown three-dimensional data generating method of claim 5, wherein, For any first ray, if the intersection point of the first ray and the three-dimensional data of the object comprises multiple, the minimum value of the distance information from the multiple intersection points to the origin is determined, and the minimum value is taken as the pixel value of the pixel point in the depth image corresponding to the object and having a mapping relationship with the first ray. The correction mask is determined based on the tooth site edge three-dimensional data, comprising:

12. The crown three-dimensional data generating method according to claim 3, wherein The spherical projection is performed on the tooth site edge three-dimensional data to obtain the tooth site edge two-dimensional line; The correction mask is determined based on the tooth site edge two-dimensional line. The tooth site edge three-dimensional data comprises multiple line segments; 13. The crown three-dimensional data generating method according to claim 12, wherein The spherical projection is performed on the tooth site edge three-dimensional data to obtain the tooth site edge two-dimensional line, comprising: The second rays from the origin of the three-dimensional rectangular coordinate system to the end points of each line segment in the multiple line segments are determined, and the position information of each pixel point in the two-dimensional image and having a mapping relationship with the second rays is determined based on the unit direction of the second rays. ​ connecting the pixel points in the two-dimensional image according to the connection relationship between the end points of each line segment in the tooth site edge three-dimensional data, to obtain the tooth site edge two-dimensional line; wherein the pixel value of the pixel point in the two-dimensional image located in the preset range around the tooth site edge two-dimensional line is set to 1, and the pixel value of the pixel point outside the preset range is set to 0.

14. The crown three-dimensional data generating method of claim 2, wherein, The corrected crown depth data is based on a corrected crown depth image representation; The spherical depth de-projection of the corrected crown depth data obtains the crown three-dimensional data of the target tooth site, including: Based on the position information of the target pixel point with a non-zero pixel value on the corrected crown depth image, a plurality of third rays are determined with the origin of the three-dimensional rectangular coordinate system as the fixed point and having a mapping relationship with the target pixel point. For any third ray, a three-dimensional point in the unit direction of the third ray is determined, and the distance information between the three-dimensional point and the origin is the pixel value of the pixel point having a mapping relationship with the third ray. Based on the three-dimensional point corresponding to the target pixel point and the three-dimensional point corresponding to the designated neighborhood pixel point of the target pixel point, the crown three-dimensional data of the target tooth site is determined; the designated neighborhood pixel point is the pixel point with a non-zero pixel value within the neighborhood range of the target pixel point.

15. The crown three-dimensional data generating method according to any one of claims 1 to 14, wherein, The crown depth data prediction model is trained based on the depth data of the tooth site sample, the surrounding tooth depth data of the tooth site sample, and the crown depth data label of the tooth site sample.

16. A crown three-dimensional data generating apparatus, wherein, including: The acquisition module is configured to acquire tooth site three-dimensional data of a target tooth site and surrounding tooth three-dimensional data of the target tooth site, and perform spherical depth projection on the tooth site three-dimensional data and the surrounding tooth three-dimensional data to obtain tooth site depth data and surrounding tooth depth data; The prediction module is configured to apply a crown depth data prediction model based on the tooth site depth data and the surrounding tooth depth data to determine the crown depth data of the target tooth site; The generation module is configured to generate the crown three-dimensional data of the target tooth site based on the crown depth data of the target tooth site.

17. An electronic device comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, wherein, The processor executes the computer program to realize the crown three-dimensional data generation method of any one of claims 1-15.

18. A non-transitory computer readable storage medium having stored thereon a computer program, wherein, The computer program is executed by the processor to realize the crown three-dimensional data generation method of any one of claims 1-15.

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