阅读说明：本技术 一种牙齿矫治器的结构优化方法、装置和系统 (Structure optimization method, device and system of tooth appliance ) 是由 史春宝 史春生 许奎雪 李宁 康树靖 岳术同 王振国 于 2020-05-23 设计创作，主要内容包括：本发明提供了一种牙齿矫治器的结构优化方法、装置和系统,所述方法包括：获取口腔内的图像信息,并基于所述图像信息生成牙颌数字模型；在所述牙颌数字模型的基础上通过位移构建,生成等厚隐形矫治器模型；对所述等厚隐形矫治器模型进行有限元分析,以得到所述等厚隐形矫治器模型中各处的厚度补偿量与该处矫治力大小的线性关系；根据各处的厚度补偿量与该处矫治力大小的线性关系,生成变厚度隐形矫治器,并通过3D打印技术得到所述变厚度隐形矫治器。从而解决了现有技术中缺乏涉及厚度数据支持、热压膜成型无法获知矫治器厚度而导致的矫治精度较低的技术问题。(The invention provides a method, a device and a system for optimizing the structure of a dental appliance, wherein the method comprises the following steps: acquiring image information in an oral cavity, and generating a dental digital model based on the image information; generating an equal-thickness invisible appliance model by displacement construction on the basis of the dental digital model; carrying out finite element analysis on the constant-thickness invisible appliance model to obtain a linear relation between the thickness compensation quantity of each position in the constant-thickness invisible appliance model and the size of the correction force of the position; and generating a variable-thickness invisible appliance according to the linear relation between the thickness compensation quantity of each part and the correction force of the part, and obtaining the variable-thickness invisible appliance through a 3D printing technology. Therefore, the technical problem that the correction precision is low due to the fact that thickness data support is not involved and the thickness of the correction device cannot be known in hot-pressing film forming in the prior art is solved.)

1. A method of structurally optimizing a dental appliance, the method comprising:

acquiring image information in an oral cavity, and generating a dental digital model based on the image information;

generating an equal-thickness invisible appliance model by displacement construction on the basis of the dental digital model;

carrying out finite element analysis on the constant-thickness invisible appliance model to obtain a linear relation between the thickness compensation quantity of each position in the constant-thickness invisible appliance model and the size of the correction force of the position;

and generating a variable-thickness invisible appliance according to the linear relation between the thickness compensation quantity of each part and the correction force of the part, and obtaining the variable-thickness invisible appliance through a 3D printing technology.

2. The method of claim 1, wherein the performing finite element analysis on the constant-thickness invisible appliance model specifically comprises:

tetrahedral elements with intermediate nodes are selected as defining elements for finite element analysis.

3. The method of claim 1, wherein the performing finite element analysis on the constant-thickness invisible appliance model specifically comprises:

and selecting a free mesh division mode as a defined mesh division mode of finite element analysis.

4. The structure optimization method according to claim 1, wherein the linear relationship between the thickness compensation amount and the correction force is as follows:

y＝1.2x；

wherein y is the correcting force, and x is the thickness compensation amount.

5. A device for optimising the configuration of a dental appliance, for use in carrying out the method of any one of claims 1 to 4, the device comprising:

the dental model acquisition unit is used for acquiring image information in the oral cavity and generating a dental digital model based on the image information;

the equal-thickness model building unit is used for generating an equal-thickness invisible appliance model through displacement building on the basis of the dental digital model;

the finite element analysis unit is used for carrying out finite element analysis on the constant-thickness invisible appliance model to obtain the linear relation between the thickness compensation quantity of each position in the constant-thickness invisible appliance model and the size of the correcting force of the position;

and the 3D printing unit is used for generating the variable-thickness invisible appliance according to the linear relation between the thickness compensation quantity at each position and the correction force at the position, and obtaining the variable-thickness invisible appliance through a 3D printing technology.

6. The structural optimization device of claim 5, wherein the finite element analysis unit is specifically configured to:

tetrahedral elements with intermediate nodes are selected as defining elements for finite element analysis.

7. The structural optimization device of claim 5, wherein the finite element analysis unit is specifically configured to:

and selecting a free mesh division mode as a defined mesh division mode of finite element analysis.

8. The apparatus for structural optimization of claim 5, wherein the linear relationship between the thickness compensation amount and the correction force is as follows:

y＝1.2x；

wherein y is the correcting force, and x is the thickness compensation amount.

9. A structural optimization system, characterized in that the system comprises: a processor and a memory;

the memory is to store one or more program instructions;

the processor, configured to execute one or more program instructions to perform the method of any of claims 1-4.

10. A computer storage medium comprising one or more program instructions for execution by a fabric optimization system to perform the method of any one of claims 1-4.

Technical Field

The invention relates to the technical field of orthodontic appliances, in particular to a method, a device and a system for optimizing the structure of a dental appliance.

Background

The invisible orthodontic technology is a technology that orthodontic force generated by the deformation of a polymer membrane under stress acts on teeth to be moved so as to straighten the teeth. The existing technology is mainly to manufacture the orthodontic appliance by a hot-pressing film forming technology, and the thickness of the orthodontic appliance obtained by the method cannot be known, so that the orthodontic effect of teeth cannot be accurately controlled and is influenced. Meanwhile, at present, the related mechanics research on the invisible correction technology at home and abroad is less, the research on how much the thickness of each part of the invisible correction device can accurately move the teeth under different moving modes is less, and data support cannot be provided for designing the variable-thickness invisible correction device, so that the development of the technology to the accurate correction direction is restricted.

Disclosure of Invention

The invention provides a method, a device and a system for optimizing the structure of a tooth appliance, which solve the technical problem of low correction precision caused by the lack of support of thickness data and the incapability of obtaining the thickness of the appliance through hot-pressing film forming in the prior art at least partially.

In order to solve the above technical problems, the present invention provides a method for optimizing a structure of a dental appliance, the method comprising:

acquiring image information in an oral cavity, and generating a dental digital model based on the image information;

generating an equal-thickness invisible appliance model by displacement construction on the basis of the dental digital model;

carrying out finite element analysis on the constant-thickness invisible appliance model to obtain a linear relation between the thickness compensation quantity of each position in the constant-thickness invisible appliance model and the size of the correction force of the position;

and generating a variable-thickness invisible appliance according to the linear relation between the thickness compensation quantity of each part and the correction force of the part, and obtaining the variable-thickness invisible appliance through a 3D printing technology.

Further, the performing finite element analysis on the equal-thickness invisible appliance model specifically includes:

tetrahedral elements with intermediate nodes are selected as defining elements for finite element analysis.

Further, the performing finite element analysis on the equal-thickness invisible appliance model specifically includes:

and selecting a free mesh division mode as a defined mesh division mode of finite element analysis.

Further, the linear relationship between the thickness compensation amount and the correction force at the position is as follows:

y＝1.2x；

wherein y is the correcting force, and x is the thickness compensation amount.

The invention also provides a device for optimising the configuration of a dental appliance, for implementing the method as described above, said device comprising:

the dental model acquisition unit is used for acquiring image information in the oral cavity and generating a dental digital model based on the image information;

the equal-thickness model building unit is used for generating an equal-thickness invisible appliance model through displacement building on the basis of the dental digital model;

the finite element analysis unit is used for carrying out finite element analysis on the constant-thickness invisible appliance model to obtain a linear relation between the thickness compensation quantity of each position in the constant-thickness invisible appliance model and the size of the correction force of the position;

and the 3D printing unit is used for generating the variable-thickness invisible appliance according to the linear relation between the thickness compensation quantity at each position and the correction force at the position, and obtaining the variable-thickness invisible appliance through a 3D printing technology.

Further, the finite element analysis unit is specifically configured to:

tetrahedral elements with intermediate nodes are selected as defining elements for finite element analysis.

Further, the finite element analysis unit is specifically configured to:

and selecting a free mesh division mode as a defined mesh division mode of finite element analysis.

Further, the linear relationship between the thickness compensation amount and the correction force at the position is as follows:

y＝1.2x；

wherein y is the correcting force, and x is the thickness compensation amount.

The present invention also provides a structural optimization system, the system comprising: a processor and a memory;

the memory is to store one or more program instructions;

the processor is configured to execute one or more program instructions to perform the method as described above.

The present invention also provides a computer storage medium having one or more program instructions embodied therein for execution by a configuration optimization system to perform the method as described above.

According to the structure optimization method, device and system of the tooth appliance, provided by the invention, image information in an oral cavity is obtained through scanning, and a dental jaw digital model is generated based on the image information; generating an equal-thickness invisible appliance model by displacement construction on the basis of the digital dental model; carrying out finite element analysis on the constant-thickness invisible appliance model to obtain a linear relation between the thickness compensation quantity of each position in the constant-thickness invisible appliance model and the size of the correction force of the position; and generating a variable-thickness invisible appliance according to the linear relation between the thickness compensation quantity of each part and the correction force of the part, and obtaining the variable-thickness invisible appliance through a 3D printing technology. In this way, the method determines the stress position and size of the teeth by carrying out finite element analysis on the equal-thickness orthodontic appliance, determines the thickness of each part of the orthodontic appliance according to the numerical relationship between the orthodontic force and the thickness of the orthodontic appliance, and applies the appropriate orthodontic force to the teeth to be moved so as to achieve the aim of accurate movement without influencing the posture of the teeth to be immovable; the middle process is omitted, the generation cost and the manufacturing period are shortened, the manufacturing precision is improved, the relation between the correcting force and the thickness is determined, the thickness of the correcting device is convenient to design, and meanwhile, the 3D printing processing correcting device is adopted, so that the processing precision is improved. Therefore, the technical problem that the correction precision is low due to the fact that thickness data support is not involved and the thickness of the correction device cannot be known in hot-pressing film forming in the prior art is solved.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention and not to limit the invention. In the drawings:

FIG. 1 is a flow chart of a method of structural optimization of a dental appliance in accordance with an embodiment of the present invention;

fig. 2 is a flow chart of a specific implementation scenario of the structure optimization method according to the embodiment of the present invention;

FIG. 3 is a schematic structural view of a structural optimization device for a dental appliance in an embodiment of the present invention;

FIG. 4 is a schematic structural view of a structural optimization system for a dental appliance in accordance with an embodiment of the present invention;

fig. 5 is a structural diagram of an appliance under a specific scenario in an embodiment of the present invention.

Detailed Description

The preferred embodiments of the present invention will be described in conjunction with the accompanying drawings, and it will be understood that they are described herein for the purpose of illustration and explanation and not limitation.

According to the structure optimization method of the tooth appliance, the jaw digital model is obtained through an intraoral scanning method, tooth separation and tooth arrangement are carried out on the jaw digital model according to reverse software, an equal-thickness invisible appliance model is constructed, the linear relation between the thickness of each part of the appliance and the size of the appliance force is obtained through finite element analysis, then the variable-thickness appliance digital model is designed and manufactured by means of 3D printing equipment, and through improvement on indirect manufacturing process routes, an intermediate manufacturing process is omitted, so that the process route is shortened, the cost and the period are saved, the thickness of the appliance can be designed in advance to determine the appliance force of each part, the effect of accurate movement of teeth is achieved, and the tooth appliance precision is improved.

In one embodiment, as shown in fig. 1, the method for optimizing the structure of the dental appliance provided by the present invention comprises the following steps:

s1: acquiring image information in an oral cavity, and generating a dental digital model based on the image information; in the actual operation process, image information in the oral cavity can be obtained through oral cavity scanning (for example, taking an intra-oral X-ray film, etc.), the image information at least includes a tooth image to be corrected, generally includes images of all teeth and gums in the whole oral cavity, and the generated digital model of the jaw is a three-dimensional model which includes a tooth model and a gum model.

S2: generating an equal-thickness invisible appliance model by displacement construction on the basis of the dental digital model; according to different dental digital models and in combination with different requirements of users, the construction of the equal-thickness invisible appliance model is pertinently carried out, so that the model is more matched with the tooth shapes and oral cavity structures of different users. That is to say, specifically, the equal-thickness invisible appliance model is generated through displacement construction on the basis of the dental digital model; the method comprises the steps of obtaining a continuous curved surface of the dental crown in Geomagic software, extracting according to an object, smoothing the obtained curved surface to obtain an inner surface of an appliance, offsetting the inner surface of the appliance by a preset thickness, such as 0.6mm, according to a normal direction through an offset command, and combining the two surfaces through a hole filling command to form an equal-thickness invisible appliance model.

S3: carrying out finite element analysis on the equal-thickness invisible appliance model to obtain a linear relation between the thickness compensation quantity of each position in the equal-thickness invisible appliance model and the size of the correction force of the position; the method comprises the steps of determining the stress position and size of teeth by carrying out finite element analysis on an equal-thickness orthodontic appliance, determining the thickness of each part of the orthodontic appliance according to the numerical relationship between the obtained orthodontic force and the thickness of the orthodontic appliance and combining different orthodontic parameters such as different orthodontic positions, required deformation and the like, applying the appropriate orthodontic force to teeth to be moved to achieve the purpose of accurate movement, and not influencing the postures of the teeth to be immovable.

For example, specifically, finite element analysis is carried out on the constant-thickness invisible appliance model; the finite element analysis process comprises the steps of grid division, boundary condition definition, constraint and load addition and calculation processing model. The teeth are evenly divided into three parts from top to bottom, and constraints are applied according to actual conditions. The specific parameter settings may be: the free grid division is defined as SmartSize, accuracy 0.4mm, modulus of elasticity 2.4GPa, density 1.38g/cm³Poisson's ratio of 0.3.

In the finite element analysis, specifically, a tetrahedral unit with an intermediate node is selected as a definition unit of the finite element analysis, and the definition unit attribute of the finite element analysis selects a tetrahedral unit with an intermediate node, so that a high-quality tetrahedron can be better distinguished. The free mesh division mode is selected as the defined mesh division mode of the finite element analysis, and the defined mesh division mode of the finite element analysis is the free mesh division mode, so that the working time of a computer is reduced, and the efficiency is improved.

Specifically, the linear relationship between the thickness compensation amount and the correction force at the position is as follows: y is 1.2 x;

wherein y is the correcting force, and x is the thickness compensation amount.

S4: and generating a variable-thickness invisible appliance according to the linear relation between the thickness compensation quantity of each part and the correction force at the part, and obtaining the variable-thickness invisible appliance through a 3D printing technology. As shown in fig. 2, the initially printed variable-thickness invisible appliance needs to be try-fitted by the patient, and if the fitting comfort is not enough or matched, the procedure returns to step S3 for re-optimization until the try-fitting is successful; if the fitting is successful, the matching of the variable-thickness invisible appliance is prompted to be successful, and the variable-thickness invisible appliance can be generated.

The following supplementary description is made with reference to specific scenarios:

according to the above embodiment, as shown in fig. 5, for example, a tooth 21 of a patient needs to be moved in parallel to the lingual side, the tooth 21 is first segmented and extracted by the geographic software, the extracted surface is offset by 0.6mm by the offset command, and then the extracted surfaces are combined into the equal-thickness invisible appliance model. The teeth 21 require a corrective force of 0.24N when moved, and the thickness compensation amount obtained from the numerical relationship obtained by finite element analysis should be 0.2 mm. The Geomagic software selects the lip side surface of the constant-thickness invisible appliance in a lasso mode and offsets 0.2mm, and finally generates a variable-thickness invisible appliance model.

In a specific embodiment, the structural optimization method of the dental appliance provided by the invention comprises the steps of obtaining image information in an oral cavity through scanning, and generating a dental digital model based on the image information; generating an equal-thickness invisible appliance model by displacement construction on the basis of the dental digital model; carrying out finite element analysis on the equal-thickness invisible appliance model to obtain a linear relation between the thickness compensation quantity of each position in the equal-thickness invisible appliance model and the size of the correction force of the position; and generating a variable-thickness invisible appliance according to the linear relation between the thickness compensation quantity of each part and the correction force at the part, and obtaining the variable-thickness invisible appliance through a 3D printing technology. In this way, the method determines the stress position and size of the tooth by carrying out finite element analysis on the equal-thickness appliance, determines the thickness of each part of the appliance according to the numerical relationship between the obtained correction force and the thickness of the appliance, and applies the appropriate correction force to the tooth to be moved to achieve the purpose of accurate movement without influencing the posture of the tooth to be immovable; the middle process is omitted, the generation cost and the manufacturing period are shortened, the manufacturing precision is improved, the relation between the correcting force and the thickness is determined, the thickness of the correcting device is convenient to design, and meanwhile, the 3D printing processing correcting device is adopted, so that the processing precision is improved. Therefore, the technical problem that the correction precision is low due to the fact that thickness data support is involved and the thickness of the correction device cannot be known in hot-pressing film forming in the prior art is solved.

In addition to the above method, the present invention also provides a device for structurally optimizing a dental appliance for carrying out the method as described above, as shown in fig. 3, which in one embodiment comprises:

a dental model acquisition unit 100 configured to acquire image information in an oral cavity and generate a dental digital model based on the image information; in the actual operation process, image information in the oral cavity can be obtained through oral cavity scanning (for example, taking an X-ray film in the oral cavity, etc.), the image information at least includes a tooth image to be corrected, generally includes images of all teeth and gums in the whole oral cavity, and the generated digital model of the jaw is a three-dimensional model which includes a tooth model and a gum model.

The equal-thickness model building unit 200 is used for building an equal-thickness invisible appliance model through displacement on the basis of the dental digital model; according to different dental digital models and in combination with different requirements of users, the construction of the equal-thickness invisible appliance model is pertinently carried out, so that the model is more matched with the tooth shapes and oral cavity structures of different users.

A finite element analysis unit 300, configured to perform finite element analysis on the equal-thickness invisible appliance model to obtain a linear relationship between the thickness compensation amount at each position in the equal-thickness invisible appliance model and the correction force at the position; finite element analysis is carried out on the equal-thickness orthodontic appliance, the stress position and the size of the tooth are determined, the thickness of each position of the orthodontic appliance is determined according to the numerical relationship between the orthodontic force and the thickness of the orthodontic appliance and by combining different orthodontic positions, required deformation and other orthodontic parameters, the proper orthodontic force for the tooth to be moved is applied to the tooth to be moved, the aim of accurate movement is achieved, and the posture of the tooth to be immovable is not influenced.

In the finite element analysis, specifically, a tetrahedral unit with an intermediate node is selected as a definition unit of the finite element analysis, and the definition unit attribute of the finite element analysis selects a tetrahedral unit with an intermediate node, so that a high-quality tetrahedron can be better distinguished. The free mesh division mode is selected as the defined mesh division mode of the finite element analysis, and the defined mesh division mode of the finite element analysis is the free mesh division mode, so that the working time of a computer is reduced, and the efficiency is improved.

Specifically, the linear relationship between the thickness compensation amount and the correction force at the position is as follows: y is 1.2 x;

wherein y is the correcting force, and x is the thickness compensation amount.

And the 3D printing unit 400 is used for generating the variable-thickness invisible appliance according to the linear relation between the thickness compensation quantity at each position and the correction force at the position, and obtaining the variable-thickness invisible appliance through a 3D printing technology. The primarily printed variable-thickness invisible appliance needs to be tried on by a patient, and if the fitting comfort is not enough or not matched, the step S3 is returned to optimize again until the fitting is successful; if the try-on is successful, the matching success of the variable-thickness invisible appliance is prompted, and the variable-thickness invisible appliance can be generated.

In the above specific embodiment, the structural optimization device of the dental appliance provided by the present invention obtains image information in an oral cavity by scanning, and generates a dental digital model based on the image information; generating an equal-thickness invisible appliance model by displacement construction on the basis of the dental digital model; carrying out finite element analysis on the equal-thickness invisible appliance model to obtain a linear relation between the thickness compensation quantity of each position in the equal-thickness invisible appliance model and the size of the correction force of the position; and generating a variable-thickness invisible appliance according to the linear relation between the thickness compensation quantity of each part and the correction force at the part, and obtaining the variable-thickness invisible appliance through a 3D printing technology. In this way, the method determines the stress position and size of the tooth by carrying out finite element analysis on the equal-thickness appliance, determines the thickness of each part of the appliance according to the numerical relationship between the obtained correction force and the thickness of the appliance, and applies the appropriate correction force to the tooth to be moved to achieve the purpose of accurate movement without influencing the posture of the tooth to be immovable; the middle process is omitted, the generation cost and the manufacturing period are shortened, the manufacturing precision is improved, the relation between the correcting force and the thickness is determined, the thickness of the correcting device is convenient to design, and meanwhile, the 3D printing processing correcting device is adopted, so that the processing precision is improved. Therefore, the technical problem that the correction precision is low due to the fact that thickness data support is involved and the thickness of the correction device cannot be known in hot-pressing film forming in the prior art is solved.

Further, the present invention also provides a structure optimization system, as shown in fig. 4, the system includes: a processor 201 and a memory 202; the memory is to store one or more program instructions; the processor is configured to execute one or more program instructions to perform the method as described above.

The present invention also provides a computer storage medium having one or more program instructions embodied therein for execution by a configuration optimization system to perform the method as described above.

In an embodiment of the invention, the processor may be an integrated circuit chip having signal processing capability. The processor may be a general-purpose processor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA) or other programmable logic device, discrete gate or transistor logic device, discrete hardware component.

The various methods, steps and logic blocks disclosed in the embodiments of the present invention may be implemented or performed. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like. The steps of the method disclosed in connection with the embodiments of the present invention may be directly implemented by a hardware decoding processor, or may be implemented by a combination of hardware and software modules in the decoding processor. The software module may be located in a random access memory, a flash memory, a read only memory, a programmable read only memory or an electrically erasable programmable memory, a register, etc. storage media well known in the art. The processor reads the information in the storage medium and completes the steps of the method in combination with the hardware.

The storage medium may be a memory, for example, which may be volatile memory or nonvolatile memory, or which may include both volatile and nonvolatile memory.

The nonvolatile memory may be a Read-only memory (ROM), a Programmable ROM (PROM), an Erasable PROM (EPROM), an Electrically Erasable EPROM (EEPROM), or a flash memory.

The volatile memory may be a Random Access Memory (RAM) which serves as an external cache. By way of example and not limitation, many forms of RAM are available, such as static random access memory (staticlam, SRAM), dynamic random access memory (dynamic RAM, DRAM), Synchronous Dynamic Random Access Memory (SDRAM), double data rate synchronous dynamic random access memory (DoubleDataRateSDRAM, ddr SDRAM), enhanced synchronous dynamic random access memory (enhanced SDRAM, ESDRAM), synchronous link dynamic random access memory (synchlink DRAM, SLDRAM), and direct memory bus random access memory (DRRAM).

The storage media described in connection with the embodiments of the invention are intended to comprise, without being limited to, these and any other suitable types of memory.

Those skilled in the art will appreciate that the functionality described in the present invention can be implemented in a combination of hardware and software in one or more of the examples described above. When software is applied, the corresponding functionality may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. Computer-readable media includes both computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. A storage media may be any available media that can be accessed by a general purpose or special purpose computer.

It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is intended to include such modifications and variations.