Dental instrument and method of designing the same, method of designing a mounting table

Abstract

This invention provides a dental instrument and its design method, as well as a mounting platform design method. The dental instrument includes a shell-shaped orthodontic appliance and a traction device. The shell-shaped orthodontic appliance is a cavity that accommodates multiple teeth. A mounting platform protrudes from the outer surface of the shell-shaped orthodontic appliance, and the mounting platform has a mounting surface that cooperates with the traction device. The mounting surface is angled to the arch curve section corresponding to the teeth being accommodated. When the dental instrument is worn intraorally for traction, the axis of the traction device undergoes three-dimensional angular compensation, reducing the torsional force generated by the interaction between the traction device and the mounting platform on the shell-shaped orthodontic appliance. The dental instrument provided by this invention can perform angular compensation according to the traction direction of the traction device, making the force on the dental instrument during traction treatment more consistent with the treatment plan and improving treatment accuracy.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of medical devices, and relates to a dental device and a design method thereof, and a design method of a mounting table. BACKGROUND

[0002] Invisible dental aligners are increasingly accepted and used by a large number of orthodontic patients due to their aesthetic, hygienic, convenient, and good orthodontic effect. Some auxiliary orthodontic devices, such as attachments and lingual buckles, are usually used in orthodontic treatment with invisible dental aligners. Currently, the auxiliary orthodontic devices are usually installed on the teeth, and corresponding slots are provided on the invisible dental aligners to avoid the auxiliary orthodontic devices. Alternatively, the invisible dental aligners are provided with assembly parts that cooperate with the auxiliary orthodontic devices, so that the auxiliary orthodontic devices can be installed on the outer surface of the invisible dental aligners or pass through the assembly parts to cooperate with the invisible dental aligners. However, both of the above-mentioned methods have certain limitations. For example, due to individual differences, the conditions in the mouths of different people are different. The same method and installation angle are used in the process of personalized treatment, which is limited by design, such as adjustment of the traction angle.

[0003] Therefore, it is of great significance to study an assembly part provided on an invisible dental aligner and capable of adjusting the traction angle, so as to adaptively adjust the traction angle according to the requirements of the treatment plan. SUMMARY

[0004] The present application aims to overcome the defects in the prior art, and provides a dental device and a design method thereof, and a design method of a mounting table of a shell-shaped dental aligner traction device. Ultimately, the dental device can compensate for the angle according to the traction direction of the traction device, so that the force of the dental device during traction treatment is more consistent with the treatment plan, and the treatment accuracy is improved.

[0005] The present application solves the above technical problems by the following technical solutions:

[0006] A dental device comprises a shell-shaped dental aligner and a traction device. The shell-shaped dental aligner has a cavity for accommodating a plurality of teeth. An installation table is protruded from the outer surface of the shell-shaped dental aligner. An installation surface that cooperates with the traction device is provided on the installation table. The installation surface is arranged at an angle to the tooth curve section corresponding to the teeth. When the dental device is worn in the mouth for traction, the axis of the traction device produces three-dimensional angle compensation, so that the torsional force generated by the interaction between the traction device and the installation table of the shell-shaped dental aligner is reduced.

[0007] Further, the installation surface is arranged at an angle of 1-30° to the tangent plane of the buccal and lingual most point of the corresponding teeth.

[0008] Further, the three-dimensional angle compensation is a three-dimensional angle compensation of the traction device in a three-dimensional space coordinate system in which the dental instrument is located.

[0009] Further, the three-dimensional space coordinate system in which the dental instrument is located includes an X-axis along a tangent direction of a tooth center point, a Y-axis perpendicular to the X-axis on a jaw plane, and a Z-axis along a tooth long axis direction.

[0010] Further, the mounting surface is a plane or a curved surface substantially consistent with the curvature of a tooth surface.

[0011] Further, when the mounting surface is a plane, an axis of the traction device is substantially perpendicular to a surface away from the tooth of the mounting table.

[0012] Further, when the mounting surface is a curved surface, an axis of the traction device is substantially perpendicular to a tangent plane of a highest point of the curved surface.

[0013] Further, the three-dimensional angle compensation is set by a direction of a traction force of the traction device.

[0014] Further, the mounting table includes a mounting table mesial surface and a mounting table distal surface, and the mounting table mesial surface and the mounting table distal surface are convexly arranged on the outer surface of the shell-shaped dental appliance at different heights.

[0015] Further, when the traction device generates a traction force in the mesial direction, the height at which the mounting table mesial surface is convexly arranged on the outer surface of the shell-shaped dental appliance is less than the height at which the mounting table distal surface is convexly arranged on the outer surface of the shell-shaped dental appliance; when the traction device generates a traction force in the distal direction, the height at which the mounting table distal surface is convexly arranged on the outer surface of the shell-shaped dental appliance is less than the height at which the mounting table mesial surface is convexly arranged on the outer surface of the shell-shaped dental appliance.

[0016] Further, the mounting surface of the mounting table is further provided with a through hole for the traction device to pass through, and the traction device passes through the through hole and is fixed with the mounting table.

[0017] Further, the traction device includes a fixed part and a traction part, the fixed part is accommodated in the mounting table, and the traction part is arranged on the outer surface of the mounting table.

[0018] Further, the mounting surface of the mounting table and the traction device are fixedly connected by welding, bonding or riveting.

[0019] The application also provides a design method of a dental instrument, comprising:

[0020] An initial dental arch digital model is obtained, and the initial dental arch model includes a tooth digital model.

[0021] segmenting the tooth digital model to obtain a single complete tooth digital model;

[0022] designing a target treatment position of the target tooth digital model, the target treatment position including specific target positions of the single tooth digital model and a target dental arch curve after the target tooth is aligned;

[0023] designing a dental appliance according to the tooth treatment plan; the dental appliance includes a shell-shaped tooth appliance and a traction device; wherein the treatment plan includes designing the position of a traction device digital model, the traction device digital model interacts with the corresponding shell-shaped tooth appliance model to generate a traction force when performing intraoral / extraoral traction, simulating the movement of teeth to the target position, gradually changing from the relative position of the initial tooth digital model to the relative position of the target tooth digital model, generating a series of intermediate tooth digital models; according to the series of multiple intermediate tooth digital models in the treatment plan, the corresponding shell-shaped tooth appliance is designed; wherein a single shell-shaped tooth appliance includes a shell-shaped tooth appliance and a mounting table protruding from the outer surface of the shell-shaped tooth appliance, the mounting table is provided with a mounting surface matched with the traction device, and the mounting surface is arranged at an angle with the tangent plane of the dental arch curve corresponding to the tooth; when the dental appliance is worn in the mouth for traction, the axis of the traction device generates a three-dimensional angle compensation, so that the torsional force generated by the interaction between the traction device and the mounting table on the shell-shaped tooth appliance is reduced.

[0024] Further, the side of the mounting table away from the tooth is arranged at an angle with the tangent plane of the buccal and lingual most point of the corresponding tooth.

[0025] Further, the mounting surface is arranged at an angle of 1-30° with the tangent plane of the buccal and lingual most point of the corresponding tooth.

[0026] Further, the three-dimensional angle compensation is a three-dimensional angle compensation of the traction device in the three-dimensional space coordinate system of the dental appliance.

[0027] Further, the three-dimensional space coordinate system of the dental appliance includes an X-axis along the tangent direction of the tooth center point, a Y-axis perpendicular to the X-axis in the jaw plane, and a Z-axis along the tooth long axis direction.

[0028] Further, the mounting surface is a plane or a curved surface basically consistent with the tooth surface curvature.

[0029] Further, when the mounting surface is a plane, the axis of the traction device is basically perpendicular to the side of the mounting table away from the tooth.

[0030] Further, when the mounting surface is a curved surface, the axis of the traction device is basically perpendicular to the tangent plane of the highest point of the curved surface.

[0031] Further, the three-dimensional angle compensation is set by the direction of the traction force of the traction device.

[0032] Further, the mounting platform includes a mounting platform mesial surface and a mounting platform distal surface, the mounting platform mesial surface and the mounting platform distal surface are convexly provided on the shell-shaped tooth aligner outer surface at different heights.

[0033] Further, when the traction device generates traction force in the mesial direction, the height of the mounting platform mesial surface convexly provided on the shell-shaped tooth aligner outer surface is less than the height of the mounting platform distal surface convexly provided on the shell-shaped tooth aligner outer surface; when the traction device generates traction force in the distal direction, the height of the mounting platform distal surface convexly provided on the shell-shaped tooth aligner outer surface is less than the height of the mounting platform mesial surface convexly provided on the shell-shaped tooth aligner outer surface.

[0034] Further, the mounting surface of the mounting platform is further provided with a through hole for the traction device to pass through, and the traction device passes through the through hole and is fixed with the mounting platform.

[0035] Further, the traction device includes a fixed part and a traction part, the fixed part is accommodated in the mounting platform, and the traction part is provided on the outer surface of the mounting platform.

[0036] Further, the mounting surface of the mounting platform and the traction device are fixedly connected by welding, bonding or riveting.

[0037] Further, the center point of the single tooth model is selected;

[0038] According to the projection of the center point of the single tooth model to the target dental arch curve, the corresponding projection point of the single tooth model is obtained;

[0039] According to the corresponding projection point, a normal perpendicular to the tangent plane of the surface of the corresponding single tooth model is established, the height of the normal is set, the mounting platform reference point and the long axis direction of the mounting platform are established;

[0040] The angle between the mounting surface and the tangent surface of the dental arch curve of the corresponding accommodated tooth is designed;

[0041] The complete structure of the mounting platform is designed.

[0042] Further, the height of the normal is designed according to the thickness of the traction device.

[0043] Further, the traction device comprises a fixed part and a traction part, the fixed part is accommodated in the mounting table, the traction part is arranged on the outer surface of the mounting table, and the height of the normal convex is designed according to the thickness of the fixed part.

[0044] Further, the design method of the target dental arch curve comprises:

[0045] Determine the jaw plane coordinate system of the digital tooth model, wherein the design y-axis is the center line of the jaw model, and the x-axis is the axis perpendicular to the y-axis on the jaw plane;

[0046] Information input of the triangular mesh of the digital tooth model;

[0047] Calculate the average value of the coordinates of each digital tooth model triangular mesh, and project it on the jaw plane coordinate system to obtain the center point coordinates (x1, y1), …, (xn, yn) of the plurality of digital tooth models, wherein n is the number of teeth; n n );

[0048] Fit the dental arch curve to obtain the target dental arch curve.

[0049] Further, the method for fitting the dental arch curve is to use the algebraic equation of an ellipse to do least squares fitting, that is, to solve

[0050]

[0051] The obtained ellipse equation is the dental arch curve Ax 2 +By 2 =1, and the target dental arch curve is half of the composed ellipse curve, wherein A represents the long semi-axis of the ellipse, and B represents the short semi-axis of the ellipse.

[0052] Further, the step of setting the height of the normal convex according to the thickness of the fixed part comprises the selection of the mounting table reference point position and the determination of the mounting table long axis direction.

[0053] Further, the selection step of the mounting table reference point position comprises the following steps:

[0054] Specify the point (a, b) on the jaw plane;

[0055] Parameterize the dental arch curve obtained by the above method to obtain t is the parameter of the dental arch position;

[0056] Find the point on the dental arch curve closest to the specified point, that is, solve:

[0057] ​

[0058] According to the t0 obtained above, the nearest point is obtained That is the installation base reference point.

[0059] Further, the installation base reference point position determination further includes reference installation base shape, tooth lip / cheek thickness or diaphragm thickness factor determination.

[0060] Further, the installation base long axis direction selection step includes the following steps:

[0061] Designate the point (a, b) on the jaw plane;

[0062] Parameterize the dental arch curve obtained by the above method to obtain t is the parameter of the dental arch position;

[0063] Find the point on the dental arch curve closest to the designated point, that is, solve:

[0064]

[0065] According to the t0 obtained above, the nearest point is obtained

[0066] According to the t0 obtained above, the outer normal of the corresponding point on the dental arch curve is found Get the installation base long axis direction.

[0067] Further, the installation base long axis direction determination further includes installation base shape, tooth lip / cheek side factor determination.

[0068] Further, the series of intermediate dental arch digital models correspond to a series of intermediate shell-shaped tooth aligners; each of the series of intermediate shell-shaped tooth aligners is provided with an installation base, and the series of installation bases can be adjusted in angle in the treatment plan, and the positioning method of the series of installation bases includes:

[0069] Select a single target tooth model;

[0070] According to the step-by-step design in the treatment plan, each step position of the single target tooth model can be represented as a transformation matrix in the homogeneous coordinate system;

[0071]

[0072] where R 3×3 and t 3×1 represent the rotation matrix and the translation, respectively;

[0073] According to each step position of the single target tooth model, the position of the installation table is calculated, i.e. the transfer matrix is multiplied by the coordinates of the cavity model in the homogeneous coordinate system;

[0074]

[0075] wherein v 3×1 represents the coordinates of each vertex in the cavity model.

[0076] Further, the step of designing the angle between the installation surface and the tangent plane of the tooth-arch curve corresponding to the tooth accommodated by the installation surface comprises:

[0077] At each step position, the additional correction force of the installation table and the traction device is estimated;

[0078] The spatial coordinate value of the impedance center of the tooth bound to the installation table is estimated;

[0079] The installation table reference point is projected onto the side of the target tooth model on which the installation table is arranged; the installation table is arranged on the labial / buccal side or the lingual side of the target tooth;

[0080] According to the projection point, the impedance center and the correction force, the pose change of the tooth is calculated;

[0081] When the simulated tooth movement does not match the correction plan, the angle of the three-dimensional axis of the long axis of the installation table or the coordinate position of the installation table reference point is adjusted until the calculated position change of the tooth model is within the threshold range.

[0082] The application also provides a design method of a shell-shaped tooth corrector traction device installation table, the traction device installation table is applied to a shell-shaped tooth corrector, and the traction device is fixed to the traction device installation table, and the installation table design method comprises the following steps: selecting a center point of the single tooth model;

[0083] According to the center point of the single tooth model, a corresponding projection point of the single tooth model is obtained by projecting the center point onto the target tooth-arch curve;

[0084] According to the corresponding projection point, a normal perpendicular to the tangent plane corresponding to the surface of the single tooth model is established, the height of the normal protrusion is designed, the installation table reference point and the long axis direction of the installation table are established;

[0085] The angle between the installation surface and the tangent plane of the tooth-arch curve corresponding to the tooth accommodated by the installation surface is designed;

[0086] The complete structure of the installation table is designed.

[0087] Further, the height of the normal protrusion is designed according to the partial thickness of the traction device.

[0088] Further, the traction device comprises a fixed part and a traction part, the fixed part is accommodated in the mounting table, the traction part is arranged on the outer surface of the mounting table, and the height of the normal convex is designed according to the thickness of the fixed part.

[0089] Further, the design method of the target dental arch curve comprises:

[0090] Determine the jaw plane coordinate system of the digital tooth model, wherein the design y-axis is the center line of the jaw model, and the x-axis is the axis perpendicular to the y-axis on the jaw plane;

[0091] Information input of the triangular mesh of the digital tooth model;

[0092] Calculate the average value of the coordinates of each digital tooth model triangular mesh, and project it on the jaw plane coordinate system to obtain the center point coordinates (x1, y1), …, (xn, yn) of the plurality of digital tooth models, wherein n is the number of teeth; n n );

[0093] Fit the dental arch curve to obtain the target dental arch curve.

[0094] Further, the method for fitting the dental arch curve is to use the algebraic equation of an ellipse to do least squares fitting, that is, to solve

[0095]

[0096] The obtained ellipse equation is the dental arch curve Ax 2 +By 2 =1, and the target dental arch curve is half of the composed ellipse curve, wherein A represents the long semi-axis of the ellipse, and B represents the short semi-axis of the ellipse.

[0097] Further, the step of setting the height of the normal convex according to the thickness of the fixed part comprises the selection of the mounting table reference point position and the determination of the mounting table long axis direction.

[0098] Further, the selection step of the mounting table reference point position comprises the following steps:

[0099] Specify the point (a, b) on the jaw plane;

[0100] Parameterize the dental arch curve obtained by the above method to obtain t is the parameter of the dental arch position;

[0101] Find the point on the dental arch curve closest to the specified point, that is, solve:​

[0102]

[0103] According to the t0 obtained above, the nearest point is obtained That is the installation base reference point.

[0104] Further, the installation base reference point position determination further includes reference installation base shape, tooth lip / cheek thickness or diaphragm thickness factor determination.

[0105] Further, the installation base long axis direction selection step includes the following steps:

[0106] Designate the point (a, b) on the jaw plane;

[0107] Parameterize the dental arch curve obtained by the above method to obtain t is the parameter of the dental arch position;

[0108] Find the point on the dental arch curve closest to the designated point, that is, solve:

[0109]

[0110] According to the t0 obtained above, the nearest point is obtained

[0111] According to the t0 obtained above, the outer normal of the corresponding point on the dental arch curve is found Get the installation base long axis direction.

[0112] Further, the installation base long axis direction determination further includes installation base shape, tooth lip / cheek side factor determination.

[0113] Further, the series of intermediate dental arch digital models correspond to a series of intermediate shell-shaped tooth aligners; each of the series of intermediate shell-shaped tooth aligners is provided with an installation base, and the series of installation bases can be adjusted in angle in the treatment plan, and the positioning method of the series of installation bases includes:

[0114] Select a single target tooth model;

[0115] According to the step-by-step design in the treatment plan, each step position of the single target tooth model can be represented as a transformation matrix in the homogeneous coordinate system;

[0116]

[0117] Where R 3×3 and t 3×1 represent the rotation matrix and the translation, respectively;

[0118] According to each step position of the single target tooth model, the position of the mounting table is calculated, that is, the transfer matrix is multiplied by the coordinates of the cavity model in the homogeneous coordinate system.

[0119]

[0120] wherein v 3×1 represents the coordinates of each vertex in the cavity model.

[0121] Further, the step of designing the angle between the mounting surface and the tooth-arc curve section of the corresponding contained tooth comprises:

[0122] At each step position, the additional correction force of the mounting table and the traction device is estimated.

[0123] The spatial coordinate value of the impedance center of the tooth bound to the mounting table is estimated.

[0124] The mounting table reference point is projected onto the side of the mounting table set on the target tooth model; the mounting table is set on the labial / buccal side or the lingual side of the target tooth.

[0125] According to the projection point, the impedance center and the correction force, the pose change of the tooth is calculated.

[0126] When the simulated tooth movement does not match the correction plan, the angle of the three-dimensional axis of the mounting table long axis or the coordinate position of the mounting table reference point is adjusted until the calculated tooth model position change is within the threshold range.

[0127] Compared with the prior art, the beneficial effects of the present application at least include:

[0128] The dental instrument provided by the present application comprises a shell-shaped tooth corrector and a traction device. The shell-shaped tooth corrector is a cavity containing multiple teeth and can have a correction effect on the teeth, so that the teeth gradually change from an initial position to a target correction position. In addition, the shell-shaped tooth corrector further protrudes an installation table on the outer surface. The installation table is provided with a mounting surface cooperating with the traction device. The mounting surface is arranged at an angle to the tooth-arc curve section of the corresponding contained tooth. When the dental instrument is worn in the mouth for traction, the axis of the traction device produces three-dimensional angle compensation, so that the torsional force generated by the interaction between the traction device and the installation table on the shell-shaped tooth corrector is reduced. When traction is performed, the traction direction of the traction device can be angle-compensated, so that the force during the traction correction of the dental instrument is more consistent with the correction plan, and the correction accuracy is improved.

[0129] The dental instrument design method provided by this invention is to perform personalized design based on the patient's real tooth model, and the designed mounting platform is angle-compensated in three dimensions. During traction orthodontic treatment, the traction is more precise and better matches the treatment plan, thereby improving the efficiency of orthodontic treatment.

[0130] This invention also provides a design method for a mounting platform for a shell-shaped orthodontic appliance traction device. This design method can specifically create a mounting platform on the shell-shaped orthodontic appliance that matches the traction angle of the traction device. The designed mounting platform can be applied to dental instruments, enabling the traction device to generate three-dimensional angle compensation when performing traction operations in conjunction with the shell-shaped orthodontic appliance. During traction orthodontic treatment, the traction is more precise and more consistent with the treatment plan, thereby improving treatment efficiency. Attached Figure Description

[0131] Figure 1 This is a schematic diagram of the structure of a dental instrument according to a specific embodiment of the present invention.

[0132] Figure 2 for Figure 1 A-A' sectional view of one embodiment.

[0133] Figure 3 for Figure 2 A diagram illustrating the usage status.

[0134] Figure 4 for Figure 1 A-A' section view of another embodiment.

[0135] Figure 5 for Figure 4 A diagram illustrating the usage status.

[0136] Figure 6 This is a schematic diagram of the traction device 20.

[0137] Figure 7 This is a schematic diagram of the structure of another dental instrument in a specific embodiment of the present invention.

[0138] Figure 8 for Figure 7 A cross-sectional view along line B-B' of one embodiment.

[0139] Figure 9 for Figure 8 A diagram illustrating the usage status.

[0140] Figure 10 for Figure 7 A cross-sectional view along line B-B' of another embodiment.

[0141] Figure 11 for Figure 10 A diagram illustrating the usage status.

[0142] Figure 12 Flow chart for the design method of dental appliance. DETAILED DESCRIPTION

[0143] For the purposes of the present invention, the technical solutions and advantages thereof will be more apparent from the following detailed description of the embodiments thereof, taken in conjunction with the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of the present invention. Unless otherwise defined, the technical terms or scientific terms used herein should be understood as the common meanings thereof by those of ordinary skill in the art to which the present invention belongs. The terms such as “comprise” and the like used herein are intended to encompass the elements or objects recited before the terms as well as equivalents thereof, and do not exclude other elements or objects.

[0144] When orthodontic treatment is performed with a clear aligner (the same product as the shell-shaped aligner described below), some auxiliary treatment devices such as attachments, lingual buttons, etc. are usually used. At present, the auxiliary treatment devices are usually used in cooperation with the clear aligner in the following two ways: the auxiliary treatment devices are installed on the teeth, and corresponding slots are provided on the clear aligner to avoid the auxiliary treatment devices; or the clear aligner is provided with an assembly part cooperating with the auxiliary treatment devices, so that the auxiliary treatment devices can be installed on the outer surface of the clear aligner or pass through the assembly part to cooperate with the clear aligner. However, both of the above-mentioned ways have certain limitations. For example, due to individual differences, the conditions in the mouths of different people are different, and the same way and installation angle are used in the process of individualized treatment, which is limited by design, such as adjustment of the traction angle. The dental appliance provided by the present invention can compensate for the angle according to the traction direction of the traction device, so that the force of the dental appliance during traction treatment is more consistent with the treatment plan, and the treatment accuracy is improved.

[0145] EMBODIMENT

[0146] A dental appliance 1, such as Figures 1-5As shown, the dental appliance 1 includes a shell-shaped dental appliance 10 and a traction device 20. The shell-shaped dental appliance 10 has a cavity for accommodating a plurality of teeth. The shell-shaped dental appliance 10 further has a mounting platform 11 protruding from an outer surface thereof. The mounting platform 11 has a mounting surface 111 configured to cooperate with the traction device 20. The mounting surface 111 is arranged at an angle to a tooth curve section corresponding to the teeth accommodated in the cavity. When the dental appliance 1 is worn in the mouth for traction, the axis of the traction device 20 produces three-dimensional angle compensation, so that the torsional force generated by the interaction between the traction device 20 and the mounting platform 11 of the shell-shaped dental appliance 10 is reduced. The dental appliance 1 can compensate for the angle according to the traction direction of the traction device 20, so that the force acting on the dental appliance 1 during traction is more consistent with the treatment plan, thereby improving the accuracy of treatment. In one specific embodiment, the mounting surface 111 is arranged at an angle a to the tangent plane of the corresponding tooth 30, where a is 1-30°. In another embodiment, the tangent plane of the tooth 30 is the tangent plane of the most outward point in the labial / buccal direction or the lingual direction. In another embodiment, the center point of the mounting surface 111 is mapped to the tangent plane of the corresponding tooth 30.

[0147] In one embodiment, the three-dimensional angle compensation is three-dimensional angle compensation of the traction device 20 in a three-dimensional coordinate system of the dental appliance 1. The three-dimensional coordinate system includes an X-axis along the tangent direction of the center point of the tooth, a Y-axis perpendicular to the X-axis in the jaw plane, and a Z-axis along the long axis of the tooth. Since the mounting platform is a three-dimensional structure, the mounting platform has a convex three-dimensional shape in the three-dimensional coordinate system compared to the tangent plane of the corresponding tooth 30. The three-dimensional shape can produce a deviation from the axis of the traction device 20 on the corresponding different surfaces in the three-dimensional coordinate system. One of the three-dimensional surfaces can produce a deviation, or all of the three-dimensional surfaces can produce a deviation. The actual traction angle is adjusted and set accordingly.

[0148] In one embodiment, the mounting surface 111 is a flat surface or a curved surface substantially consistent with the curvature of the tooth surface. When the mounting surface 111 is a flat surface, the axis L of the traction device 20 is substantially perpendicular to the surface of the mounting platform 11 away from the tooth. As shown in FIG. 2, the mounting surface 111 is a flat surface, and the axis L of the traction device 20 is substantially perpendicular to the surface of the mounting platform 11 away from the tooth. Figure 3As shown, when a traction connector, such as a traction elastic element, is hooked onto the traction device 20, the traction direction is consistent with the direction of the mounting surface 111. At this time, the axis L of the traction device 20 is substantially perpendicular to the mounting surface 111, maximizing the traction force during traction and preventing the traction force from being dispersed due to angular deviation. The axis L of the traction device 20 is substantially perpendicular to the side of the mounting platform 11 away from the teeth; in one embodiment, the angle between the two is 80°-100°. When the mounting surface 111 is curved, the axis L of the traction device 20 is substantially perpendicular to the tangent plane at the highest point of the curved surface. When the mounting surface 111 is curved, the surface formed by the tangent plane at the highest point of the curved surface is substantially perpendicular to the axis L of the traction device 20, maximizing the traction force during traction and preventing the traction force from being dispersed due to angular deviation; in one embodiment, the angle between the two is 80°-100°.

[0149] In one embodiment, the three-dimensional angle compensation is set by the direction of the traction force of the traction device. When using a traction device for orthodontic treatment in the oral cavity, it may be intramaxillary traction, i.e., traction between two teeth / alveolar bone in a single maxillary / mandibular jaw; or intermaxillary traction, i.e., traction between two teeth / alveolar bone in both maxillary and mandibular jaws; or extramaxillary traction, i.e., traction between teeth / alveolar bone in both extramaxillary and intramaxillary jaws. Regardless of the traction method, adjustments to the traction angle may occur during traction; that is, the direction of the traction force of the traction device may not be parallel to the tangent plane of the highest point of the corresponding tooth surface, potentially causing angular deviation. Three-dimensional angle compensation compensates for this angular deviation, reducing the torsional force generated by the interaction between the traction device and the mounting platform on the shell-shaped orthodontic appliance. This prevents gaps from forming between the shell-shaped orthodontic appliance and the teeth due to inaccurate traction force direction during traction, thus reducing the appliance's fit and affecting the treatment outcome.

[0150] In one implementation, such as Figures 2-5 As shown, the mounting platform 11 includes a mesial surface 112 and a distal surface 113, with the mesial surface 112 and the distal surface 113 protruding from the outer surface of the shell-shaped orthodontic appliance at different heights. In one specific embodiment, when the traction device 20 generates traction force in the mesial direction, the height of the mesial surface 112 protruding from the outer surface of the shell-shaped orthodontic appliance 10 is less than the height of the distal surface 113 protruding from the outer surface of the shell-shaped orthodontic appliance 10; when the traction device 20 generates traction force in the distal direction, the height of the distal surface 113 protruding from the outer surface of the shell-shaped orthodontic appliance 10 is less than the height of the mesial surface 112 protruding from the outer surface of the shell-shaped orthodontic appliance 10. In both of these embodiments, the inclination direction of the mounting surface 111 is related to the traction force generated by the traction device 20.

[0151] In one embodiment, as shown in Figure 4 and Figure 5 , the mounting surface 111 of the mounting platform 11 is further provided with a through hole 1111 for the traction device 20 to pass through, and the traction device 20 passes through the through hole 1111 and is fixed with the mounting platform 11. This arrangement makes the fixation of the traction device 20 with the mounting platform 11 more secure. The traction device 20 can be a one-piece structure or a split structure. When the traction device 20 is a split structure, one part of the traction device passes through the mounting platform 11 and is fixedly connected with the other part, thereby achieving fixed connection with the mounting platform 11. When the traction device 20 is a one-piece structure, the traction device is clamped in the through hole 1111 of the mounting platform 11, thereby achieving fixed connection with the mounting platform 11. In a more specific embodiment, as shown in Figure 5 and Figure 6 , the traction device 20 includes a fixed part 21 and a traction part 22. The fixed part 21 is accommodated in the mounting platform 11, and the traction part 22 is arranged on the outer surface of the mounting platform 11. At this time, part of the traction device 20 is arranged in the mounting platform 11, so that the overall traction device 20 protrudes less on the outer surface of the shell-shaped dental appliance 10, the foreign body sensation in the mouth is smaller, and the patient wears it more comfortably.

[0152] In one embodiment, as shown in Figure 2 and Figure 3 , the mounting surface 111 of the mounting platform 11 is fixedly connected with the traction device 20 by welding, bonding, riveting, etc. Another way to fix the mounting platform 11 with the traction device 20 is that the mounting surface 111 arranged on the mounting platform 11 is fixedly connected with the bottom surface of the traction device 20, such as by welding, bonding, riveting, etc. This mounting method makes the fixation of the traction device 20 with the mounting platform 11 more secure and less likely to fall off, thereby reducing the risk of accidental swallowing.

[0153] Another dental instrument 3, as shown in Figures 7-11 , includes a shell-shaped dental appliance 30 and a traction device 40. The shell-shaped dental appliance 30 has a cavity for accommodating multiple teeth. The outer surface of the shell-shaped dental appliance 30 further protrudes a mounting platform 31. The mounting platform 31 is provided with a mounting surface 311 that cooperates with the traction device 40. The mounting surface 311 is arranged at an angle β with the tooth-arch-curve cross section, where β can be 1-30°. When the dental instrument 3 is worn in the mouth for traction, the axis of the traction device 40 produces a three-dimensional angle compensation, so that the torsional force generated by the interaction between the traction device 40 and the mounting platform 31 on the shell-shaped dental appliance 30 is reduced. The dental instrument 3 can compensate for the angle according to the traction direction of the traction device 40, so that the force acting on the dental instrument 3 during traction is more consistent with the treatment plan, thereby improving the accuracy of treatment. In another embodiment, as shown in Figures 7-11As shown in FIG. 1, the dental appliance 3, when the traction device 40 generates a traction force in the direction of the facial surface of the jaw, the height of the mounting platform facial surface 312 protruding from the outer surface of the shell-shaped dental appliance 30 is less than the height of the mounting platform gum margin surface 313 protruding from the outer surface of the shell-shaped dental appliance 10; when the traction device 40 generates a traction force in the direction of the gum, the height of the mounting platform facial surface 312 protruding from the outer surface of the shell-shaped dental appliance 30 is less than the height of the mounting platform gum margin surface 313 protruding from the outer surface of the shell-shaped dental appliance 30. In one embodiment, the mounting surface 311 of the mounting platform 31 is further provided with a through hole 3111 for the traction device 40 to pass through, and the traction device 40 passes through the through hole 3111 and is fixed with the mounting platform 31. This arrangement makes the fixation of the traction device 40 and the mounting platform 31 more secure, wherein the traction device 40 can be a one-piece structure or a split structure, when the traction device 40 is a split structure, one part of the traction device 40 passes through the mounting platform 31 and is fixedly connected with the other part, thereby achieving fixed connection with the mounting platform 31; when the traction device 40 is a one-piece structure, the traction device is clamped in the through hole 3111 of the mounting platform 31 to be fixedly connected with the mounting platform 31.

[0154] In one embodiment, as shown in FIG. 1, Figure 8 and Figure 9 the mounting surface 311 of the mounting platform 31 is fixedly connected with the traction device 40 by welding, bonding or riveting. Another way to fix the mounting platform 31 and the traction device 40 is to fix the mounting surface 311 provided on the mounting platform 31 with the bottom surface of the traction device 40, such as by welding, bonding or riveting. This mounting method makes the fixation of the traction device 40 and the mounting platform 31 more secure, and it is not easy to fall off and cause misphagia.

[0155] The present embodiment also provides a design method for a dental appliance, as shown in FIG. 1, Figure 12 comprising:

[0156] Step S11: obtaining an initial dental arch digital model, the initial dental arch model comprising a dental digital model; wherein the dental digital model can be an upper / lower dental digital model, and the dental digital model can be obtained from initial dental arch digital model information or intermediate state dental arch digital model information during treatment. The initial dental arch digital model information or the intermediate state dental arch digital model information can be obtained by intraoral scanning, or by scanning the user's dental arch model. The initial dental state information can specifically include tooth shape, gum position, etc., and can further include root information obtained from CBCT data (Cone beam CT, also known as cone beam CT).

[0157] Step S12: segmenting the tooth digital model to obtain a single complete tooth digital model; the segmentation method can adopt any existing method, for example, the following steps are adopted:

[0158] S121: selecting a first type of feature point on the digital tooth model to be segmented, wherein the digital tooth model is a triangular facet model.

[0159] S122: classifying a second type of feature point in the digital tooth model according to the first type of feature point to determine the tooth to which each second type of feature point belongs.

[0160] S123: merging the second type of feature point belonging to each tooth respectively to obtain the digital tooth region of each single tooth after segmentation of the digital tooth model;

[0161] The first type of feature point is a triangular facet vertex selected based on the digital tooth model and used to guide the segmentation of each single tooth in the tooth row, and the second type of feature point is a triangular facet vertex selected based on the digital tooth model and used to represent the overall shape of the digital tooth model; that is, the first type of feature point is used to guide the segmentation of the tooth row, and the second type of feature point is a feature point for specific segmentation of the tooth row; through the segmentation guidance of the first type of feature point, the second type of feature point can be accurately classified into each tooth, thereby improving the segmentation accuracy of the tooth row.

[0162] By selecting the first type of feature point on the digital tooth model, and then classifying and collecting the second type of feature point on the digital tooth model according to the first type of feature point, the segmentation of a single tooth is realized. Since the two types of feature points are selected based on the overall digital tooth model, the classification information of the feature points covers the classification features of the overall digital tooth model, so even if the model has noise data, the noise data will be evenly distributed to the global data, making the entire segmentation method have high fault tolerance, the single tooth can be segmented more accurately, and the integrity of each tooth is ensured.

[0163] Step S13: designing a target treatment position of a target tooth digital model, wherein the target treatment position includes a specific target position of a single tooth digital model and a target dental arch curve after alignment of the target tooth; wherein the target treatment position can be determined according to the treatment target position determined by the clinician and the patient, and after determining each target treatment position of the single jaw, the target dental arch curve after alignment of the target tooth can be obtained.

[0164] In a specific embodiment, the design method of the target dental arch curve includes the following steps:

[0165] Step S131: Determine the jaw plane coordinate system of the digital tooth model, wherein the design y-axis is the center line of the dental model, and the x-axis is the axis perpendicular to the y-axis on the jaw plane; so that the digital tooth model is placed in the jaw plane coordinate system.

[0166] Step S132: Information input of the triangular mesh of the digital tooth model; the digital tooth model is composed of a plurality of triangular meshes, and the obtained digital tooth model is converted into a triangular mesh and placed in the jaw plane coordinate system.

[0167] Step S133: Calculate the average value of the coordinates of each digital tooth model triangular mesh, and project it onto the jaw plane coordinate system to obtain the center point coordinates (x1, y1), …, (x n ,y n ), wherein n is the number of teeth;

[0168] Step S134: Fit the dental arch curve to obtain the target dental arch curve. The specific method of fitting the dental arch curve is to use the algebraic equation of an ellipse to do least squares fitting, that is, to solve

[0169]

[0170] The obtained ellipse equation is the dental arch curve Ax 2 +By 2 =1, and the target dental arch curve is half of the ellipse curve, wherein A represents the long semi-axis of the ellipse, B represents the short semi-axis of the ellipse, and i represents the ith tooth.

[0171] Step S14: designing dental appliances according to the dental treatment plan; the dental appliances include shell-shaped dental appliances and traction devices; wherein the treatment plan includes designing the positions of the digital model of the traction device, the digital model of the traction device interacts with the corresponding shell-shaped dental appliance model to generate a traction force when performing intraoral / extraoral traction, simulating the movement of teeth to the target position, gradually changing the relative position from the initial dental digital model to the relative position of the target tooth digital model to generate a series of intermediate dental digital models; designing the corresponding shell-shaped dental appliance according to the series of intermediate dental digital models in the treatment plan; wherein a single shell-shaped dental appliance includes a shell-shaped dental appliance and a mounting table protruding from the outer surface of the shell-shaped dental appliance, the mounting table is provided with a mounting surface matched with the traction device, and the mounting surface is arranged at an angle with the tooth curve section of the corresponding tooth receiving dental arch; when the dental appliance is worn in the mouth for traction, the axis of the traction device generates a three-dimensional angle compensation, so that the torsional force generated by the interaction between the traction device and the mounting table on the shell-shaped dental appliance is reduced. More specifically, the dental appliance can compensate for the angle according to the traction direction of the traction device, so that the force of the dental appliance during traction treatment is more consistent with the treatment plan, improving the accuracy of treatment.

[0172] In one embodiment, the specific method of the mounting table includes:

[0173] S141: selecting the center point of the single tooth model; wherein the center point is the center point of the single tooth, and the single jaw tooth includes multiple teeth, so the center points corresponding to the multiple teeth have multiple.

[0174] S142: projecting the center point of the single tooth model to the target dental arch curve to obtain the corresponding projection point of the single tooth model; according to the target dental arch curve determined in the above step, the center point of the single tooth model is projected and set, so there are multiple projection points corresponding to the number of teeth on the target dental arch curve.

[0175] S143: establishing a normal perpendicular to the tangent plane of the outermost point of the surface of the corresponding single tooth model according to the corresponding projection point, setting the height of the normal protrusion, and establishing the mounting table reference point and the long axis direction of the mounting table; in one embodiment, the height of the normal protrusion can be set according to the thickness of part of the traction device, such as the traction device including a fixed part and a traction part, the height of the normal protrusion can be set according to the thickness of the fixed part, so that the mounting table can accommodate the fixed part of the traction device, and when worn, the shell-shaped dental appliance can be more closely fitted to the tooth surface, reducing the generation of gaps and improving the wrapping rate of the shell-shaped dental appliance, thereby improving the treatment efficiency.

[0176] The selection of the mounting table reference point position and the determination of the long axis direction of the mounting table include the following specific steps:

[0177] S1431: specify a point (a, b) on the jaw plane;

[0178] S1432: parameterize the dental arch curve obtained by the above method to obtain where t is the parameter of the dental arch position;

[0179] S1433: find the point on the dental arch curve closest to the specified point, that is, solve

[0180]

[0181] S1434: according to the t0 obtained by the above solution, find the closest point which is the reference point of the mounting platform.

[0182] S1435: The reference point position of the mounting platform also includes the determination of the shape of the mounting platform, the lip / buccal thickness of the tooth, or the film thickness factor.

[0183] S1436: According to the t0 obtained by the above solution, find the outer normal of the corresponding point on the dental arch curve which is the direction of the long axis of the mounting platform;

[0184] S1437: The direction of the long axis of the mounting platform also includes the determination of the shape of the mounting platform, the lip / buccal surface of the tooth.

[0185] S144: Design the angle between the mounting surface and the tangent plane of the corresponding dental arch curve; When using the traction device for traction correction in the oral cavity, it may be intra-arch traction, that is, the traction between two teeth / alveolar bones in the upper / lower jaw single jaw; or inter-arch traction, that is, the traction between two teeth / alveolar bones in the upper and lower jaws of the upper and lower jaws; or extra-arch traction, that is, the traction between the extra-arch and intra-arch teeth / alveolar bones. Regardless of the above traction method, the traction angle may be adjusted during traction, that is, the direction of the traction force of the traction device may not be parallel to the tangent plane of the highest point of the corresponding tooth surface, and the three-dimensional angle compensation may be used to compensate for the angle deviation, so that the torsional force generated by the interaction between the traction device and the mounting platform on the shell-shaped tooth corrector is reduced. The gap between the shell-shaped tooth corrector and the tooth caused by the inaccurate direction of the traction force during the traction process, which reduces the wrapping of the shell-shaped tooth corrector on the tooth and affects the correction effect. More specifically, the angle between the mounting surface and the tangent plane of the corresponding dental arch curve is designed according to the actual traction requirement.

[0186] In one specific embodiment, the additional correction force of the mounting platform and the traction device is estimated at each step position;

[0187] Estimate the spatial coordinate value of the impedance center of the tooth bound to the installation platform;

[0188] Project the installation platform reference point onto the bound target tooth model to set the side of the installation platform; the installation platform is set on the labial / buccal side or the lingual side of the target tooth;

[0189] According to the projection point, the impedance center and the orthodontic force, the pose change of the tooth is calculated;

[0190] When the simulated tooth movement does not match the treatment plan, the angle of the long axis three-dimensional axis of the installation platform or the coordinate position of the installation platform reference point is adjusted until the calculated tooth digital model position change is within the threshold range.

[0191] S145: design the complete structure of the installation platform. The installation platform is a complete three-dimensional structure, which is convex on the outer surface of the shell-shaped tooth appliance. After the installation surface is determined, the remaining connection surface of the shell-shaped tooth appliance and the installation surface are smoothly connected. The final installation platform has less foreign body sensation in the mouth and the patient wears it more comfortably.

[0192] The dental instrument designed by the above design method can realize the specific structure in the specific implementation of the above dental instrument, and the specific structure of the dental instrument is described above and will not be repeated here.

[0193] A design method of a shell-shaped tooth appliance traction device installation platform, the traction device installation platform is applied to a shell-shaped tooth appliance, and the traction device is fixed to the traction device installation platform. The installation platform design method comprises:

[0194] S241: Select the center point of the single tooth model; wherein the center point is the center point of the single tooth, and the single jaw tooth comprises a plurality of teeth, so the center points corresponding to the plurality of teeth have a plurality of center points.

[0195] S242: Project the center point of the single tooth model to the target dental arch curve to obtain the projection point corresponding to the single tooth model; according to the target dental arch curve determined in the above step, the center point of the single tooth model is projected and set, so there are a plurality of projection points corresponding to the number of teeth on the target dental arch curve.

[0196] S243: According to the corresponding projection point, a normal perpendicular to the tangent plane of the outermost point of the corresponding single tooth model surface is established, the height of the protrusion towards the normal is set, and the installation table reference point and the long axis direction of the installation table are established; in one of the embodiments, the height of the protrusion towards the normal can be set according to the thickness of part of the traction device, such as the traction device including a fixed part and a traction part, the height of the protrusion towards the normal can be set according to the thickness of the fixed part, so that the installation table can accommodate the fixed part of the traction device, and when worn, the shell-shaped dental appliance is more closely attached to the tooth surface, reduces the generation of gaps, improves the wrapping rate of the shell-shaped dental appliance, and thus improves the treatment efficiency.

[0197] Wherein, the selection of the installation table reference point position and the determination of the long axis direction of the installation table include the following specific steps:

[0198] S2431: specifying a point (a, b) on the jaw plane;

[0199] S2432: parameterizing the dental arch curve obtained by the above method to obtain Wherein, t is the parameter of the dental arch position;

[0200] S2433: find the point on the dental arch curve closest to the specified point, that is, solve

[0201]

[0202] S2434: according to the t0 obtained by the above solution, find the nearest point That is, the installation table reference point.

[0203] S2435: The installation table reference point position determination also includes reference to the shape of the installation table, the lip / buccal thickness of the tooth or the diaphragm thickness factor determination.

[0204] S2436: According to the t0 obtained by the above solution, find the outer normal of the corresponding point on the dental arch curve That is, the direction of the long axis of the installation table;

[0205] S2437: The direction of the long axis of the installation table also includes the shape of the installation table, the lip / buccal side factor of the tooth.

[0206] S244: design the angle between the installation surface and the tangent plane of the dental arch curve corresponding to the tooth to be accommodated; when traction is performed in the oral cavity using the traction device, it can be intramaxillary traction, i.e., traction between two teeth / alveolar bones in a single jaw of the upper / lower jaw; or intermaxillary traction, i.e., traction between two teeth / alveolar bones in the upper jaw and the lower jaw; or extramaxillary traction, i.e., traction between the teeth / alveolar bones inside and outside the jaw. Regardless of the above-mentioned traction mode, the traction angle can be adjusted during traction, i.e., the direction of the traction force of the traction device can not be parallel to the tangent plane of the highest point of the surface of the corresponding tooth, and an angle deviation can occur. Three-dimensional angle compensation compensates for the angle deviation, so that the torsional force generated by the interaction between the traction device and the installation platform on the shell-shaped tooth appliance is reduced, and the gap between the shell-shaped tooth appliance and the tooth caused by the inaccurate direction of the traction force during traction is avoided, which reduces the wrapping of the shell-shaped tooth appliance on the tooth and affects the treatment effect. More specifically, the angle between the installation surface and the tangent plane of the dental arch curve corresponding to the tooth to be accommodated is designed according to the actual traction requirement.

[0207] In one specific embodiment, the additional treatment force of the installation platform and the traction device is estimated at each step position;

[0208] The spatial coordinate value of the impedance center of the tooth bound to the installation platform is estimated;

[0209] The installation platform reference point is projected onto the side of the target tooth model where the installation platform is set; the installation platform is set on the labial / buccal side or the lingual side of the target tooth;

[0210] According to the projection point, the impedance center and the treatment force, the pose change of the tooth is calculated;

[0211] When the simulated tooth movement does not match the treatment plan, the angle of the three-dimensional axis of the long axis of the installation platform or the coordinate position of the installation platform reference point is adjusted until the calculated tooth digital model position change is within the threshold range.

[0212] S245: design the complete structure of the installation platform. The installation platform is a complete three-dimensional structure, which is convex on the outer surface of the shell-shaped tooth appliance. After the installation surface is determined, the remaining connection surface of the shell-shaped tooth appliance and the installation surface is smoothly connected, and finally the obtained installation platform has less foreign body sensation in the mouth, and the patient wears it more comfortably.

[0213] After the installation platform is designed, it can be applied to the shell-shaped tooth appliance and used in cooperation with the traction device. The specific application method is described in the design method of dental instruments, which is not repeated here.

[0214] Although the specific embodiments of the present application have been described above, it is understood by those skilled in the art that the present application is only illustrated by way of example, and the scope of protection of the present application is defined by the appended claims. Those skilled in the art can make various changes or modifications to the embodiments without departing from the principles and essence of the present application, and such changes and modifications fall within the scope of protection of the present application.

Claims

1. A dental appliance comprising a shell-like tooth aligner and a traction device, the shell-like tooth aligner being a cavity accommodating a plurality of teeth, characterized in that, The outer surface of the shell-shaped tooth appliance is further provided with a mounting table, and the mounting table is provided with a mounting surface matched with the traction device, and the mounting surface is arranged at an angle with a tooth-arch-curve tangent plane corresponding to the tooth. The mounting surface is arranged at an angle of 1-30° with a tangent plane of a buccal-lingual outermost point of the tooth.

2. The dental instrument of claim 1, wherein, The three-dimensional angle compensation is a three-dimensional angle compensation of the traction device in a three-dimensional space coordinate system of the dental appliance.

3. The dental instrument of claim 2, wherein, The three-dimensional space coordinate system of the dental appliance includes an X-axis along a tangent direction of a tooth center point, a Y-axis perpendicular to the X-axis on a jaw plane, and a Z-axis along a tooth long-axis direction.

4. The dental instrument of claim 1, wherein, When the mounting surface is a plane, the axis of the traction device is substantially perpendicular to a far-tooth side of the mounting table.

5. The dental instrument of claim 1, wherein, When the mounting surface is a curved surface, the axis of the traction device is substantially perpendicular to a tangent plane of a highest point of the curved surface.

6. The dental instrument of claim 1, wherein, The three-dimensional angle compensation is set by a traction force direction of the traction device.

7. The dental instrument of claim 1, wherein, The mounting table includes a mounting table mesial surface and a mounting table distal surface, and the mounting table mesial surface and the mounting table distal surface are provided at different heights on the outer surface of the shell-shaped tooth appliance.

8. The dental instrument of claim 7, wherein, When the traction device generates a traction force in the mesial direction, the height of the mounting table mesial surface provided on the outer surface of the shell-shaped tooth appliance is smaller than the height of the mounting table distal surface provided on the outer surface of the shell-shaped tooth appliance; when the traction device generates a traction force in the distal direction, the height of the mounting table distal surface provided on the outer surface of the shell-shaped tooth appliance is smaller than the height of the mounting table mesial surface provided on the outer surface of the shell-shaped tooth appliance.

9. The dental instrument of claim 1, wherein, The mounting surface of the mounting table is further provided with a through hole for the traction device to pass through, and the traction device passes through the through hole and is fixed with the mounting table.

10. The dental instrument of claim 9, wherein, The traction device includes a fixed part and a traction part, the fixed part is accommodated in the mounting table, and the traction part is arranged on the outer surface of the mounting table.

11. The dental instrument of claim 1, wherein, The mounting surface of the mounting table and the traction device are fixedly connected by welding, bonding or riveting.

12. A method of designing a dental instrument, characterized by, The method comprises: an initial dental arch digital model is obtained, and the initial dental arch model includes a tooth digital model; the tooth digital model is segmented to obtain a single complete tooth digital model; a target treatment position of a target tooth digital model is designed, and the target treatment position includes a specific target position of a single tooth digital model and a target tooth-arch curve after the target tooth is aligned; According to a dental appliance design method, a dental appliance is designed according to a dental treatment plan; the dental appliance comprises a shell-shaped dental appliance and a traction device; wherein the treatment plan comprises designing the position of a traction device digital model, the traction device digital model interacts with a corresponding shell-shaped dental appliance model, generates a traction force when performing intraoral / extraoral traction, simulates the movement of teeth to a target position, gradually changes from the relative position of the initial dental digital model to the relative position of the target dental digital model, and generates a series of intermediate dental digital models; a corresponding shell-shaped dental appliance is designed according to a series of multiple intermediate dental digital models in the treatment plan; wherein a single shell-shaped dental appliance comprises a shell-shaped dental appliance and a mounting table protruding from the outer surface of the shell-shaped dental appliance, the mounting table is provided with a mounting surface matched with the traction device, and the mounting surface is arranged at an angle with the tooth curve section surface corresponding to the tooth; when the dental appliance is worn in the mouth for traction, the axis of the traction device generates a three-dimensional angle compensation, so that the torsional force generated by the interaction between the traction device and the mounting table on the shell-shaped dental appliance is reduced. The mounting surface is arranged at an angle of 1-30° with the tangent plane corresponding to the buccal and lingual most outer point of the tooth, and the mounting surface is a plane or a curved surface substantially consistent with the tooth surface curvature.

13. The method of designing a dental appliance according to claim 12, wherein, The three-dimensional angle compensation is a three-dimensional angle compensation of the traction device in a three-dimensional space coordinate system of the dental appliance.

14. The method of designing a dental instrument according to claim 13, wherein, The three-dimensional space coordinate system of the dental appliance comprises an X-axis along the tangent direction of the tooth center point, a Y-axis perpendicular to the X-axis in the jaw plane, and a Z-axis along the tooth long axis direction.

15. The method of designing a dental appliance of claim 12, wherein, When the mounting surface is a plane, the axis of the traction device is substantially perpendicular to the side of the mounting table away from the tooth.

16. The method of designing a dental appliance of claim 12, wherein, When the mounting surface is a curved surface, the axis of the traction device is substantially perpendicular to the tangent plane of the highest point of the curved surface.

17. The method of designing a dental appliance of claim 13, wherein, The three-dimensional angle compensation is set by the direction of the traction force of the traction device.

18. The method of designing a dental appliance of claim 12, wherein, The mounting table comprises a mounting table mesial surface and a mounting table distal surface, and the mounting table mesial surface and the mounting table distal surface protrude from the outer surface of the shell-shaped dental appliance at different heights.

19. The method of designing a dental appliance according to claim 18, wherein, When the traction device generates a traction force in the mesial direction, the height of the mounting table mesial surface protruding from the outer surface of the shell-shaped dental appliance is less than the height of the mounting table distal surface protruding from the outer surface of the shell-shaped dental appliance; when the traction device generates a traction force in the distal direction, the height of the mounting table distal surface protruding from the outer surface of the shell-shaped dental appliance is less than the height of the mounting table mesial surface protruding from the outer surface of the shell-shaped dental appliance.

20. The method of designing a dental appliance of claim 12, wherein, The mounting surface of the mounting table is further provided with a through hole for the traction device to pass through, and the traction device passes through the through hole and is fixed with the mounting table.

21. The method of designing a dental appliance of claim 20, wherein, The traction device comprises a fixed part and a traction part, the fixed part is accommodated in the mounting table, and the traction part is arranged on the outer surface of the mounting table.

22. The method of designing a dental appliance of claim 12, wherein, The mounting surface of the mounting table and the traction device are fixedly connected by welding, bonding or riveting.

23. The method of designing a dental appliance of claim 12, wherein, The design method of the mounting table comprises: selecting the center point of the single tooth model; According to the center point of the single tooth model projected to the target dental arch curve, a corresponding projection point of the single tooth model is obtained; A normal is established which is perpendicular to the tangent plane of the surface of the corresponding single tooth model according to the corresponding projection point, and the height of the normal is set, and the reference point of the mounting table and the long axis direction of the mounting table are established; The angle between the mounting surface and the tangent section of the dental arch curve corresponding to the tooth contained is designed; The complete structure of the mounting table is designed.

24. The method of designing a dental appliance of claim 23, wherein, The height of the normal is designed according to the thickness of the traction device.

25. The method of designing a dental appliance of claim 24, wherein, The traction device comprises a fixed part and a traction part, the fixed part is accommodated in the mounting table, the traction part is arranged on the outer surface of the mounting table, and the height of the normal is designed according to the thickness of the fixed part.

26. The method of designing a dental appliance of claim 23, wherein, The design method of the target dental arch curve comprises: Determine the jaw plane coordinate system of the digital tooth model, wherein the designed y-axis is the center line of the tooth model, and the x-axis is the axis perpendicular to the y-axis on the jaw plane; Information input of the triangular mesh of the digital tooth model; The average value of the triangular mesh coordinates of each digitized tooth model is calculated, and is projected onto the jaw plane coordinate system to obtain the center point coordinates (x1, y1), …, (xn, yn) of the plurality of digitized tooth models, wherein n is the number of the plurality of teeth. n n ​​ Fitting the dental arch curve to obtain the target dental arch curve.

27. The method of designing a dental appliance of claim 26, wherein, The method for fitting the dental arch curve is to use the algebraic equation of an ellipse to do least square fitting, that is, to solve The obtained ellipse equation is the dental arch curve Ax 2 +By 2 = 1, the target dental arch curve is half of the ellipse curve, wherein A represents the reciprocal of the square of the long semi-axis of the ellipse, and B represents the reciprocal of the square of the short semi-axis of the ellipse.

28. The method of designing a dental appliance of claim 25, wherein, The step of establishing the normal which is perpendicular to the tangent plane of the surface of the corresponding single tooth model according to the corresponding point and setting the height of the normal protruding to the normal according to the thickness of the fixed part comprises the selection of the reference point position of the mounting table and the determination of the long axis direction of the mounting table.

29. The method of designing a dental appliance of claim 27, wherein, The selection step of the reference point position of the mounting table comprises the following steps: Specifying a point (a, b) on the jaw plane; Parametrizing the dental arch curve obtained by the above method, we obtain t is a parameter of the dental arch position. Finding the point on the dental arch curve closest to the specified point, that is, solving: According to the value of t obtained above, denoted as t0, the closest point is obtained That is, the installation base reference point.

30. The method of designing a dental appliance of claim 29, wherein, The determination of the reference point position of the mounting table further comprises the determination of the shape of the mounting table, the lip / buccal thickness of the tooth or the diaphragm thickness factor.

31. The method of designing a dental appliance of claim 27, wherein, The selection step of the long axis direction of the mounting table comprises the following steps: Specifying a point (a, b) on the jaw plane; Parametrizing the dental arch curve obtained by the above method, we obtain t is a parameter of the dental arch position. Finding the point on the dental arch curve closest to the specified point, that is, solving: From the value of t thus solved, denoted t0, the closest point is found According to the t0 solved above, the external normal of the corresponding point on the dental arch curve is found The long axis direction of the mounting table is obtained.

32. The method of designing a dental appliance of claim 31, wherein, The determination of the direction of the long axis of the mounting table further comprises the determination of the shape of the mounting table, the lip / buccal side of the tooth factor.

33. The method of designing a dental appliance of claim 12, wherein, The series of intermediate tooth-jaw digital models correspond to a series of intermediate shell-shaped tooth correctors; the series of intermediate shell-shaped tooth correctors are all provided with mounting tables, and the mounting tables in the series can be adjusted in angle in the correction plan, and the positioning method of the series of mounting tables comprises: Selecting a single target tooth model; According to the steps in the correction plan design, the position of the single target tooth model at each step is obtained, which can be represented as a transfer matrix in the homogeneous coordinate system; where R 3×3 and t 3×1 represent the rotation matrix and translation, respectively; According to the position of the single target tooth model at each step, the position of the mounting table is respectively solved, that is, the transfer matrix is multiplied by the coordinates of the cavity model in the homogeneous coordinate system; where v 3×1 represents the coordinates of each vertex in the cavity model.

34. The method of designing a dental appliance of claim 23, wherein, The step of designing the angle between the mounting surface and the tangent section of the dental arch curve corresponding to the tooth contained comprises: At each step position, the additional correction force of the mounting table and the traction device is estimated; The spatial coordinate value of the impedance center of the tooth bound to the mounting table is estimated; Projecting the mounting base reference point to the binding target tooth model to set one side of the mounting base, and obtaining a projection point; the mounting base is set on the labial / buccal side or the lingual side of the target tooth; According to the projection point, the impedance center and the orthodontic force, calculating the pose change of the tooth; When the simulation tooth movement process does not match the orthodontic plan, adjusting the angle of the long axis three-dimensional axis of the mounting base or the coordinate position of the mounting base reference point until the calculated tooth model position change is within the threshold range.

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