Design method of digital model of expander and invisible orthodontic appliance

Abstract

The application relates to a method for manufacturing an expander and a hidden orthodontic device, and relates to the technical field of oral orthodontics. A single-tooth digital dental model is obtained based on a digital dental model, and a vertical height of a top of a palate and a bite plane is obtained based on the single-tooth digital dental model, a connecting position of the expander and the device is determined, a digital expander model is obtained based on a software method, the obtained digital expander model has strong technical universality, does not need to excessively depend on personal experience, and the manufactured expander is more comfortable to wear.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of orthodontics, in particular to a design method of a digital model of an arch expander, a manufacturing method of a target tooth model, a manufacturing method of a clear aligner and the clear aligner. BACKGROUND

[0002] Malocclusion refers to a malformation of teeth, jaws and craniofacial features caused by congenital genetic factors or postnatal environment such as diseases, bad oral habits and abnormal tooth replacement during growth and development. Dental arch constriction is a common malocclusion in orthodontic clinics. Many patients have upper dental arch constriction and need to expand the upper dental arch.

[0003] In the existing design method of a digital model of an arch expander, either a metal spiral arch expander is manufactured, which has a large overall volume and is uncomfortable to wear, or measurement and judgment are made based on X-ray films, which requires the personal experience of technicians for measurement and judgment and has a strong dependence on personal technical level and experience. SUMMARY

[0004] The present application mainly solves the technical problem of providing a design method of a digital model of an arch expander and a clear aligner, which has low manufacturing difficulty, low dependence on personal technology, and the manufactured arch expander and clear aligner are more comfortable to wear.

[0005] According to a first aspect, a design method of a digital model of an arch expander is provided in an embodiment, comprising:

[0006] obtaining a digital dental arch model of the upper jaw, the digital dental arch model comprising a digital tooth model and a digital upper jaw model;

[0007] segmenting the digital dental arch model into single-tooth digital dental arch models, the single-tooth digital dental arch models comprising single-tooth digital tooth models and digital upper jaw models;

[0008] obtaining an occlusal plane according to the single-tooth digital dental arch models;

[0009] obtaining an upper jaw apex according to the single-tooth digital dental arch models;

[0010] calculating the vertical height of the upper jaw apex and the occlusal plane;

[0011] obtaining the horizontal distance between the central fossae of two first premolars as a first distance according to the single-tooth digital tooth models;

[0012] obtaining the horizontal distance between the central fossae of two first molars as a second distance according to the single-tooth digital tooth models;

[0013] According to the single-tooth digital tooth model, the width of each incisor tooth is obtained, and the sum of the widths of the upper jaw incisor teeth is calculated;

[0014] The sum of the widths is weighted to obtain a weighted sum of the widths;

[0015] According to the size relationship between the first distance, the second distance and the weighted sum of the widths, the connection position of the expander and the appliance is determined;

[0016] According to the expansion distance, the target expansion distance is calculated;

[0017] Based on the target expansion distance and the connection position, an expander digital model is set, including an arched expander arched upward on the upper jaw side, the highest point of the arched expander being located between the upper jaw vertex and the occlusal plane, and being close to the upper jaw vertex.

[0018] In one embodiment, the occlusal plane is obtained according to the single-tooth digital tooth model, comprising:

[0019] The highest point of the mesial lingual cusp of each side of the bilateral molar is taken as the first highest point;

[0020] The mesial incisal point of the two central incisors is taken as the second highest point;

[0021] The occlusal plane is obtained according to the first highest point and the second highest point.

[0022] In one embodiment, the upper jaw vertex is obtained according to the single-tooth digital tooth model, comprising:

[0023] A parallel plane parallel to the occlusal plane is obtained, and the parallel plane is moved in the upper jaw direction, when the parallel plane is tangent to the upper jaw, the tangent point is taken as the upper jaw vertex;

[0024] The vertical height of the upper jaw vertex and the occlusal plane is calculated, comprising:

[0025] The distance between the parallel plane tangent to the upper jaw and the occlusal plane is taken as the vertical height of the upper jaw vertex and the occlusal plane.

[0026] In one embodiment, the sum of the widths is weighted to obtain a weighted sum of the widths, comprising:

[0027] A first weighted width is obtained according to the sum of the widths and a first weighting coefficient, and the size relationship between the first distance and the first weighted width is determined;

[0028] A second weighted width is obtained according to the sum of the widths and a second weighting coefficient, and the size relationship between the second distance and the second weighted width is determined.

[0029] In one embodiment, the step of determining the connection position of the expander and the aligner according to the size relationship between the first distance, the second distance and the sum of the weighted widths after calculation comprises:

[0030] determining the size relationship between the first distance and the first weighted width and the size relationship between the second distance and the second weighted width;

[0031] if the first distance is less than the first weighted width, setting the connection position of the expander and the aligner at the lingual edge of the two first premolars;

[0032] if the second distance is less than the second weighted width, setting the connection position of the expander and the aligner at the lingual edge of the two first molars.

[0033] In one embodiment, the step of determining the connection position of the expander and the aligner according to the size relationship between the first distance, the second distance and the sum of the weighted widths after calculation comprises:

[0034] determining the size relationship between the first distance and the first weighted width and the size relationship between the second distance and the second weighted width;

[0035] if the first distance is less than the first weighted width and the second distance is less than the second weighted width, setting the connection position of the expander and the aligner at the lingual edge of the two second premolars.

[0036] In one embodiment, the step of calculating the target expansion distance according to the expansion distance comprises: calculating the total expansion distance, and calculating the target expansion distance of each step according to the total expansion distance and the expansion distance of each step.

[0037] The step of setting the expander digital model based on the target expansion distance and the connection position comprises: setting the one-to-one corresponding expander digital model according to the target expansion distance of each step and the connection position.

[0038] In one embodiment, the step of calculating the total expansion distance comprises: calculating the total expansion distance according to the difference between the horizontal distance of the central fossa of the two teeth where the connection position of the expander and the aligner is located and the width.

[0039] According to the second aspect, in one embodiment, a target tooth model manufacturing method is provided, comprising: adding the expander digital model to the target digital tooth model to obtain the target tooth model through 3D printing; the expander digital model is obtained based on the above-mentioned design method of the expander digital model.

[0040] According to the third aspect, in one embodiment, a manufacturing method of a clear aligner is provided, comprising:

[0041] obtaining a target tooth model based on the target tooth model manufacturing method described above;

[0042] manufacturing a bracket-free aligner based on the target tooth model.

[0043] In an embodiment, the bracket-free aligner based on the target tooth model comprises:

[0044] obtaining a bracket-free aligner containing tooth and expander shape by hot forming on a target tooth model;

[0045] cutting the bracket-free aligner containing tooth and expander shape along the gum line or adjacent to the gum line to obtain a bracket-free aligner capable of accommodating teeth.

[0046] According to a fourth aspect, an embodiment provides an aligner comprising an expander; the expander comprises an arch-shaped structure arching upward on the palate side; the expander is realized according to the aligner manufacturing method described above.

[0047] A computer-readable storage medium, the medium storing a program executable by a processor to implement any of the above-mentioned expander digital model design method, and / or target tooth model manufacturing method, and / or aligner manufacturing method.

[0048] According to the expander digital model design method of the above-mentioned embodiment, a single tooth digital dental model is obtained based on a digital dental model, and a vertical height of the palate apex and the occlusal plane is obtained based on the single tooth digital dental model, and the connection position of the expander and the aligner is determined, so that the expander digital model is obtained based on the software method. The expander digital model obtained has strong technical universality and does not need to rely too much on personal experience, and the manufactured expander is more comfortable to wear. BRIEF DESCRIPTION OF DRAWINGS

[0049] Figure 1 Schematic diagram of numbering and classification of human teeth;

[0050] Figure 2 Flowchart of the expander digital model design method of an embodiment of the present application;

[0051] Figure 3 Flowchart of obtaining the occlusal plane of an embodiment of the present application;

[0052] Figure 4 Flowchart of the method of determining the connection position of the expander and the aligner of an embodiment of the present application;

[0053] Figure 5The method flow chart for determining the connection position of the expander and the appliance according to another embodiment of the present application;

[0054] Figure 6 The method flow chart for manufacturing the invisible appliance according to an embodiment of the present application;

[0055] Figure 7 The method flow chart for manufacturing the invisible appliance according to an embodiment of the present application;

[0056] Figure 8 The structure diagram of the invisible appliance according to an embodiment of the present application. DETAILED DESCRIPTION

[0057] The application will be further described in details through specific embodiments and the accompanying drawings. In different embodiments, similar elements are marked with similar element numbers. In the following embodiments, many details are described in order to make the present application better understood. However, those skilled in the art can easily recognize that some features can be omitted in different cases, or can be replaced by other elements, materials or methods. In some cases, some operations related to the present application are not shown or described in the specification in order to avoid the core part of the present application being overwhelmed by too much description, and it is not necessary to describe these related operations in details for those skilled in the art according to the description in the specification and the general technical knowledge in the art.

[0058] In addition, the features, operations or characteristics described in the specification can be combined in any appropriate manner to form various embodiments. Meanwhile, the steps or actions in the method description can also be sequentially adjusted or adjusted in a manner that is obvious to those skilled in the art. Therefore, the various sequences in the specification and the drawings are only for the purpose of clearly describing a certain embodiment, and do not mean that the sequence is necessary, unless otherwise stated that a certain sequence must be followed.

[0059] The serial numbers of components in this paper, such as "first", "second", etc., are only used to distinguish the described objects, and have no sequence or technical meaning. Unless otherwise specified, the "connection" and "coupling" in the present application include direct and indirect connection (coupling).

[0060] In order to accurately understand the technical solutions and inventive concepts of the present application, some orthodontic techniques will be briefly described.

[0061] Please refer to Figure 1 According to the classification of shape and function, there are incisors, which are located in the front of the oral cavity, a total of 8, such as Figure 1The teeth numbered 11, 12, 21, 22, 31, 41, 32 and 42, wherein 11, 12, 21 and 22 are upper jaw incisors; canines, located at the corners of the mouth, a total of 4, such as Figure 1 The teeth numbered 13, 23, 33 and 43; first premolars, located behind the canines, a total of 4, such as Figure 1 The teeth numbered 14, 24, 34 and 44, wherein 14 and 24 are upper jaw first premolars; second premolars, located behind the first premolars, a total of 4, such as Figure 1 The teeth numbered 15, 25, 35 and 45, wherein 15 and 25 are upper jaw second premolars; first molars, located behind the first premolars, a total of 4, such as Figure 1 The teeth numbered 16, 26, 36 and 46, wherein 16 and 26 are upper jaw first molars; second molars, located behind the first molars, a total of 4, such as Figure 1 The teeth numbered 17, 27, 37 and 47, wherein 17 and 27 are upper jaw second molars; third molars, located behind the second molars, a total of 4, such as Figure 1 The teeth numbered 18, 28, 38 and 48, wherein 18 and 28 are upper jaw third molars.

[0062] In the existing design method of the digital model of the expander, either a metal spiral expander is manufactured, the overall volume is large, and the wearing is not comfortable, or the measurement and judgment are based on X-ray films, and the measurement and judgment need to depend on the personal experience of the technician, and the dependence on the personal technical level experience is strong. In order to obtain more comfortable wearing and technical universality, and not to depend too much on the personal level experience, please refer to Figure 2 The present application provides a design method of a digital model of an expander in an embodiment, comprising:

[0063] Step S01, obtaining a digital maxillary dental model, the digital dental model comprising a digital tooth model and a digital maxillary model.

[0064] Specifically, the patient's oral cavity can be scanned by a digital oral scanner, so as to obtain the digital maxillary dental model of the patient through the oral scanning software.

[0065] Step S02, dividing the digital dental model into a single tooth digital dental model, the single tooth digital dental model comprising a single tooth digital tooth model and a digital maxillary model.

[0066] Step S03, obtaining the occlusal plane according to the single tooth digital dental model.

[0067] In one specific embodiment, please refer to Figure 3 The specific method for obtaining the occlusal plane comprises:

[0068] Step S0301, the highest point of the mesial lingual cusp of each side of the bilateral molar is taken as the first highest point.

[0069] A straight line that bisects the craniofacial part into two equal parts is called the midline, and similarly, the midline also divides the dental arch into two symmetrical parts. We call the position of the teeth near the midline as the mesial position. In this specific embodiment, the highest point of the mesial lingual cusp of each side of the bilateral first molar is taken as the first highest point, and two first highest points are obtained. In the specific embodiment, the highest point of the mesial lingual cusp of each side of the bilateral first molar can be taken as the first highest point. Figure 1 The two teeth numbered 16 and 26, i.e. the highest points of the mesial lingual cusp of the bilateral first molar, are taken as the first highest point.

[0070] Step S0302, the mesial incisal point of the two incisors is taken as the second highest point.

[0071] The mesial incisal point of the two incisors is taken as the second highest point, and one second highest point is obtained.

[0072] Step S0303, the occlusal plane is obtained according to the first highest point and the second highest point.

[0073] The plane obtained based on the two first highest points and one second highest point is taken as the occlusal plane.

[0074] Step S04, the palatal apex is obtained according to the single-tooth digital dental model.

[0075] In one specific embodiment, the specific method for obtaining the palatal apex includes:

[0076] A parallel plane parallel to the above-mentioned occlusal plane is obtained, and the parallel plane is moved in the direction of the palate. When the parallel plane is tangent to the palate, the tangent point is taken as the palatal apex.

[0077] Step S05, the vertical height of the palatal apex from the occlusal plane is calculated.

[0078] In one specific embodiment, the vertical height of the palatal apex from the occlusal plane is calculated, including:

[0079] The distance between the parallel plane tangent to the palate and the occlusal plane is taken as the vertical height of the palatal apex from the occlusal plane. In one specific embodiment, a plane parallel to the occlusal plane is defined, and the plane is moved from the direction away from the palate to the direction of the occlusal plane. When the plane is tangent to the palate, the distance between the plane and the occlusal plane is the vertical height we need.

[0080] Step S06, the horizontal distance between the two central fossae of the first premolar is taken as the first distance according to the single-tooth digital dental model.

[0081] Referring to Fig. 1, the horizontal distance between the two first premolar central fossae numbered 14 and 24 is obtained as the first distance, which is denoted as D1 herein. Figure 1

[0082] Step S07, the horizontal distance between the two first molar central fossae is obtained as the second distance according to the single-tooth digital tooth model.

[0083] Referring to Fig. 1, the horizontal distance between the two first molar central fossae numbered 16 and 26 is obtained as the second distance, which is denoted as D2 herein. Figure 1

[0084] Step S08, the width of each incisor is obtained according to the single-tooth digital tooth model, and the sum of the widths of the upper incisors is calculated.

[0085] Referring to Fig. 1, the widths of the four incisors numbered 11, 12, 21 and 22 are obtained, and the sum of the widths of the four incisors is calculated and denoted as P. Figure 1

[0086] Step S09, the sum of the widths is weighted to obtain the weighted sum of the widths.

[0087] In one embodiment, the weighting coefficient of the first distance is 1 / 0.8, and the weighting coefficient of the second distance is 1 / 0.64. Then, the first weighted width P1=P / 0.8 can be obtained according to the sum of the widths and the first weighting coefficient, and the second weighted width P2=P / 0.64 can be obtained according to the sum of the widths and the second weighting coefficient. Thus, the size relationship between D1 and P1 and the size relationship between D2 and P2 can be obtained.

[0088] Step S10, the size relationship between the first distance and the weighted sum of the widths and the size relationship between the second distance and the weighted sum of the widths are determined to determine the connection position of the expander and the appliance.

[0089] Referring to Fig. 1, the method for determining the connection position of the expander and the appliance includes: Figure 4

[0090] Step S1001, the size relationship between the first distance and the first weighted width and the size relationship between the second distance and the second weighted width are determined.

[0091] Step S1002, if the first distance is less than the first weighted width, the connection position of the expander and the appliance is set at the lingual side edge of the two first premolars.

[0092] Step S1003, if the second distance is less than the second weighted width, the connection position of the expander and the appliance is set at the lingual side edge of the two first molars.

[0093] ​​​​In one embodiment, the size relationship between D1 and P1 is determined, the size relationship between D2 and P2 is determined, if D1 is less than P1 and D2 is greater than P2, the connecting position of the expander and the appliance is set on the lingual edge of teeth numbered 14 and 24, if D1 is greater than P1 and D2 is less than P2, the connecting position of the expander and the appliance is set on the lingual edge of teeth numbered 16 and 26.

[0094] Please refer to Figure 5 The method for determining the connecting position of the expander and the appliance comprises:

[0095] In step S1011, the size relationship between the first distance and the first weighted width and the size relationship between the second distance and the second weighted width are determined.

[0096] In step S1012, if the first distance is less than the first weighted width and the second distance is less than the second weighted width, the connecting position of the expander and the appliance is set on the lingual edge of the two second premolars.

[0097] In one embodiment, the size relationship between D1 and P1 is determined, the size relationship between D2 and P2 is determined, if D1 is less than P1 and D2 is less than P2, the connecting position of the expander and the appliance is set on the lingual edge of teeth numbered 15 and 25, i.e. in the case of simultaneous narrowness, the connecting position of the expander and the appliance is set on the lingual edge of the middle teeth.

[0098] In step S11, the target expansion distance is calculated according to the expansion distance.

[0099] In one embodiment, the specific method for calculating the target expansion distance comprises calculating the total expansion distance, and calculating the target expansion distance of each step according to the total expansion distance and the expansion distance of each step. In one embodiment, the expansion distance of each step is 0.5mm, and assuming that the total expansion distance is 2.8mm, at least 6 expansions are required, and a total of 6 expanders are required. The total expansion distance can be obtained according to L=P-D, wherein L is the total expansion distance, and D is the horizontal distance of the central fossa of the two teeth where the connecting position of the expander and the appliance is located.

[0100] In step S12, the expander digital model is set based on the target expansion distance and the connecting position, including an arched expander arched upward on the palatal side, and the highest point of the arched expander is located between the palatal apex and the occlusal plane and close to the palatal apex.

[0101] In one embodiment, the expander digital model is set based on the target expansion distance and the connecting position, comprising: setting an expander digital model corresponding to each target expansion distance and connecting position.

[0102] The digital model of the expander obtained based on the method has strong versatility, does not need to rely on personal experience too much, and the manufactured expander is more comfortable to wear.

[0103] In an embodiment, the application provides a target tooth model manufacturing method, including: adding the digital model of the expander to the target digital tooth model, and obtaining the target tooth model through 3D printing; the digital model of the expander is obtained based on the design method of the digital model of the expander.

[0104] For reference Figure 6 In an embodiment of the application, a method for manufacturing a clear aligner is provided, including:

[0105] In step S21, a target tooth model is obtained, and the target tooth model is obtained based on the target tooth model manufacturing method.

[0106] In step S22, a clear aligner without a bracket is manufactured based on the target tooth model.

[0107] For reference Figure 7 In an embodiment of the application, the method steps of step S22 include:

[0108] In step S2201, a clear aligner without a bracket containing the shape of a tooth and an expander is obtained through hot forming on the target tooth model.

[0109] In step S2202, the clear aligner without a bracket containing the shape of a tooth and an expander is cut along the gum line or adjacent to the gum line to obtain a clear aligner without a bracket capable of accommodating a tooth.

[0110] In an embodiment of the application, a clear aligner is provided, including an expander; the expander includes an arch-shaped structure arched upward on the side of the palate; and the expander is manufactured according to the method for manufacturing a clear aligner.

[0111] In an embodiment of the application, a computer-readable storage medium is provided, and the medium stores a program which can be executed by a processor to implement any of the design methods of the digital model of the expander, the target tooth model manufacturing method, and / or the clear aligner manufacturing method.

[0112] Those skilled in the art can understand that all or part of the functions of various methods in the above embodiments can be realized by hardware or by a computer program. When all or part of the functions in the above embodiments are realized by a computer program, the program can be stored in a computer readable storage medium, which can include a read-only memory, a random access memory, a magnetic disk, an optical disk, a hard disk, and the like. The above functions are realized by executing the program by a computer. For example, the program is stored in a memory of a device, and the above functions are realized by executing the program in the memory by a processor. In addition, when all or part of the functions in the above embodiments are realized by a computer program, the program can also be stored in a storage medium such as a server, another computer, a disk, an optical disk, a flash disk, or a mobile hard disk, and is saved in a memory of a local device by downloading or copying, or the system of the local device is updated, and the above functions are realized by executing the program in the memory by a processor.

[0113] The above application of specific examples to the present application is described, which is only used to help understand the present application and does not limit the present application. For those skilled in the art, according to the idea of the present application, a number of simple deductions, deformations or substitutions can be made.

Claims

1. A method for designing a digital model of an expander, characterized in that, The method comprises the following steps: acquiring a digital dental model of the upper jaw, the digital dental model comprising a digital tooth model and a digital upper jaw model; segmenting the digital dental model into a plurality of single-tooth digital dental models, the plurality of single-tooth digital dental models comprising a plurality of single-tooth digital tooth models and the digital upper jaw model; acquiring an occlusal plane according to the plurality of single-tooth digital dental models; acquiring an upper jaw vertex according to the plurality of single-tooth digital dental models; calculating the vertical height of the upper jaw vertex and the occlusal plane; acquiring the horizontal distance between the central fossae of two first premolars as a first distance according to the single-tooth digital tooth models corresponding to the two first premolars respectively; acquiring the horizontal distance between the central fossae of two first molars as a second distance according to the single-tooth digital tooth models corresponding to the two first molars respectively; acquiring the width of each incisor according to the single-tooth digital tooth models corresponding to each incisor respectively, and calculating the sum of the widths of all upper jaw incisors; performing weighted calculation on the sum of the widths to obtain a weighted sum of the widths; determining the connection position of the expander and the appliance according to the size relationship between the first distance, the second distance, and the weighted sum of the widths respectively; calculating a target expansion distance according to the expansion distance; setting an expander digital model based on the target expansion distance and the connection position, the expander digital model comprising an arched expander that is arched upward toward the upper jaw, the highest point of the arched expander being located between the upper jaw vertex and the occlusal plane and being close to the upper jaw vertex.

2. The method of designing a digital model of a palatal expander according to claim 1, wherein, The method of acquiring an occlusal plane according to the plurality of single-tooth digital dental models comprises the following steps: taking the highest point of the mesial lingual cusp of each side of the molar as a first highest point; taking the mesial incisal point of the two central incisors as a second highest point; acquiring the occlusal plane according to the first highest point and the second highest point.

3. The method of designing a digital model of a palatal expander according to any one of claims 1 to 2, wherein, The method of acquiring an upper jaw vertex according to the plurality of single-tooth digital dental models comprises the following steps: acquiring a parallel plane parallel to the occlusal plane, moving the parallel plane upward toward the upper jaw, and taking the tangent point when the parallel plane is tangent to the upper jaw as the upper jaw vertex. The method of calculating the vertical height of the upper jaw vertex and the occlusal plane comprises the following steps: taking the distance between the parallel plane tangent to the upper jaw and the occlusal plane as the vertical height of the upper jaw vertex and the occlusal plane.

4. The method of designing a digital model of a palatal expander according to claim 1, wherein, The method of performing weighted calculation on the sum of the widths to obtain a weighted sum of the widths comprises the following steps: acquiring a first weighted width according to the sum of the widths and a first weighting coefficient, and determining the size relationship between the first distance and the first weighted width; acquiring a second weighted width according to the sum of the widths and a second weighting coefficient, and determining the size relationship between the second distance and the second weighted width.

5. The method of designing a digital model of a palatal expander according to claim 4, wherein, The method of determining the connection position of the expander and the appliance according to the size relationship between the first distance, the second distance, and the weighted sum of the widths respectively comprises the following steps: determining the size relationship between the first distance and the first weighted width and the size relationship between the second distance and the second weighted width; if the first distance is less than the first weighted width, the connecting position of the expander and the appliance is set at the lingual edge of the two first premolars; if the second distance is less than the second weighted width, the connecting position of the expander and the appliance is set at the lingual edge of the two first molars.

6. The method of designing a digital model of a palatal expander according to claim 4, wherein, The connecting position of the expander and the appliance is determined according to the size relationship between the first distance, the second distance and the sum of the weighted widths. The size relationship between the first distance and the first weighted width and the size relationship between the second distance and the second weighted width are determined. if the first distance is less than the first weighted width, and the second distance is less than the second weighted width, the connecting position of the expander and the appliance is set at the lingual edge of the two second premolars.

7. The method of designing a digital model of a palatal expansion device of claim 1, wherein, The target expander distance is calculated according to the total expander distance and the distance of each step. The digital model of the expander is set according to the target expander distance and the connecting position.

8. The method of designing a digital model of a palatal expander according to claim 7, wherein, The total expander distance is calculated according to the difference between the sum of the horizontal distance of the central fossa of the two teeth where the connecting position of the expander and the appliance is located and the width.

9. A method of manufacturing a target dental model, the method comprising: The method comprises: The digital model of the expander is added to the target digital tooth model to obtain the target tooth model by 3D printing; the digital model of the expander is obtained based on the method of any one of claims 1 to 8.

10. A method of manufacturing a clear aligner, the method comprising: The method comprises: The target tooth model is obtained based on the method of claim 9; The method comprises:

11. The method of claim 10, wherein, The target tooth model is obtained based on the method of claim 9; The method comprises: The target tooth model is obtained based on the method of claim 9; 12. A clear aligner, characterized in that, The method comprises:

13. A computer-readable storage medium, characterized in that, The target tooth model is obtained based on the method of claim 9; The method comprises: The target tooth model is obtained based on the method of claim 9; The medium stores a program, and the program can be executed by a processor to implement the method of any one of claims 1-11. The medium stores a program, and the program can be executed by a processor to implement the method of any one of claims 1-11.

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