Method and system for generating digital model of invisible aligner based on traction force analysis

Abstract

The present application proposes a method and system for generating a digital model of an invisible aligner based on traction force analysis, the method comprising: obtaining a target tooth position, matching initial surface stress parameters and initial anchorage pin traction force parameters from a mechanical simulation parameter library for simulation treatment to obtain a simulated tooth position, calculating displacement deviation and rotation deviation based on the simulated tooth position and the target tooth position, adjusting the anchorage pin traction force parameters in the target rotation direction to obtain target anchorage pin traction force parameters, obtaining the displacement direction force component of the target anchorage pin traction force parameters, adjusting the surface stress parameters in the target displacement direction to obtain target surface stress parameters, and generating an invisible aligner digital model according to the target anchorage pin traction force parameters and the target surface stress parameters. The present application fully considers the influence of rotation direction adjustment on displacement direction deviation, can simultaneously meet the treatment goals of displacement direction and rotation direction, and improves the reliability of orthodontic treatment.

Description

Technical Field

[0001] This invention relates to the field of digital model generation technology for orthodontic appliances, and in particular to a method and system for generating digital models of invisible orthodontic appliances based on traction force analysis. Background Technology

[0002] Orthodontic appliances are an indispensable key technology in the field of orthodontics. During orthodontic treatment, the main considerations are the movement in the direction of displacement and rotation. However, there are complex biomechanical characteristics to consider during the movement in these two directions. Therefore, how to design orthodontic appliances in a reasonable way to ensure the treatment effect has become a problem to be solved in the field.

[0003] Existing patent CN117338453A proposes a design method for bracketless invisible aligners based on biomechanical calculations. The method includes: firstly, designing a digital model of the aligner according to the target dentition position; then, optimizing the digital model of the aligner by analyzing the biomechanical characteristics in the displacement direction, so that the calculated simulated position is consistent with the designed target position. The existing patent also discloses adjusting the structure of the digital model of the aligner through edge design until the biomechanical characteristics in the displacement direction meet the target orthodontic requirements. Only when the biomechanical characteristics of the digital model of the aligner after edge design fail to meet the orthodontic requirements in the displacement direction is the rotation direction compensation design performed to obtain the target aligner model. It is worth noting that existing patents compensate for a single rotational direction. This fails to adequately consider the deviations caused by rotational compensation when the force in the displacement direction meets the target orthodontic requirements. Specifically, existing technology, when the displacement adjustment fails to meet the orthodontic goal, introduces rotational compensation in the rotational direction. This compensation alters the appliance model structure, affecting the force in the displacement direction. Consequently, control in the displacement direction becomes susceptible to the influence of rotational adjustment, making accurate control in all directions difficult and compromising the accuracy of tooth movement control during treatment. Therefore, existing digital model designs for orthodontic appliances remain insufficient due to the influence of complex biomechanical characteristics, impacting the reliability of orthodontic treatment. Summary of the Invention

[0004] To address the aforementioned issues, this invention proposes a method and system for generating digital models of invisible aligners based on traction force analysis. This method fully considers the impact of rotational adjustments on displacement direction deviations, simultaneously meeting the orthodontic goals in both displacement and rotational directions. It also ensures accurate control of tooth movement during treatment, thereby improving the reliability of orthodontic treatment.

[0005] To achieve the above objectives, embodiments of the present invention provide a method for generating a digital model of an invisible aligner based on traction force analysis, comprising: generating a target displacement direction, a target rotation direction, and a target dentition position based on a pre-acquired current dentition position and a preset treatment target; constructing an initial aligner digital model and an initial traction hook digital model based on the target dentition position; selecting the non-overlapping portion of the current dentition position and the target dentition position to obtain the predicted implantation site for the micro-implant; simulating the initial aligner digital model being worn on the current dentition position, calculating the dentition impedance point at the current dentition position, obtaining the traction hook height corresponding to the initial traction hook digital model based on the dentition impedance point and the preset treatment target, connecting the predicted implantation site for the micro-implant and the initial traction hook digital model based on the traction hook height to obtain a first connecting unit; matching initial surface stress parameters and initial anchorage screw traction force parameters from a preset mechanical simulation parameter library based on the initial aligner digital model and the first connecting unit; and based on... The system uses a preset simulated treatment cycle to simulate treatment of the current dentition position using initial surface stress parameters and initial anchorage screw traction force parameters, resulting in a simulated dentition position. Based on the simulated and target dentition positions, displacement and rotational deviations are calculated. Based on the target rotation direction, the initial anchorage screw traction force parameters are rematched from a preset mechanical simulation parameter library until the rotational deviation meets the preset rotational deviation requirements, resulting in the target anchorage screw traction force parameters. The displacement direction force component is obtained based on the target anchorage screw traction force parameters. Based on the displacement direction force component and the target displacement direction, the initial surface stress parameters are rematched from the preset mechanical simulation parameter library until the displacement deviation meets the preset displacement deviation requirements, resulting in the target surface stress parameters. A digital model of the target traction hook is obtained based on the target anchorage screw traction force parameters, and a digital model of the target aligner is obtained based on the target surface stress parameters. Finally, a digital model of the invisible aligner is generated based on the target traction hook digital model and the target aligner digital model.

[0006] In the above scheme, an initial digital model of the orthodontic appliance and the first connecting unit are first constructed. The method of matching the corresponding mechanical parameters from the preset mechanical simulation parameter library and applying them through simulation is adopted instead of the traditional process of mechanical analysis after model optimization design. The displacement and rotational deviation between the simulated dentition position and the target dentition position are calculated. Then, the mechanical simulation application process is divided into rotational direction adjustment and displacement direction adjustment. Traction force analysis is introduced to first apply mechanical simulation in the rotational direction until the rotational deviation meets the preset rotational deviation requirement, and the traction force parameter of the target anchorage screw is obtained. Then, the displacement direction force component is obtained from the traction force parameter of the target anchorage screw, and the affected initial surface stress parameter is compensated. The initial surface stress parameter is then rematched until the displacement deviation meets the preset displacement deviation requirement, and the target surface stress parameter is obtained. Finally, the digital model of the invisible orthodontic appliance is generated, so as to realize the process of considering the possible deviation in the displacement direction after the rotational direction adjustment and making further adjustments.

[0007] This invention proposes a method for generating digital models of invisible aligners based on traction force analysis. It employs a method that considers potential deviations in the displacement direction after adjusting the rotation direction and makes further adjustments. To ensure that the resultant force in the rotation and displacement directions remains constant during treatment, after obtaining the traction force parameters of the target anchorage screw, the displacement force component is acquired and re-matched to the initial surface stress parameters. Thus, by analyzing the traction force, the influence of the rotation direction adjustment on the displacement direction deviation is fully considered, demonstrating the synergy between displacement and rotation direction control. Compared to existing technologies, this method can simultaneously meet the treatment goals in both displacement and rotation directions, ensuring the accuracy of tooth movement control during treatment and improving the reliability of orthodontic treatment. Attached Figure Description

[0008] Figure 1 A flowchart illustrating the steps of a method for generating a digital model of an invisible orthodontic appliance based on traction force analysis, provided in a certain embodiment of the present invention; Figure 2 A data fusion diagram illustrating a method for generating a digital model of an invisible orthodontic appliance based on traction force analysis, provided in a certain embodiment of the present invention; Figure 3 A schematic diagram illustrating the calculation process of dental impedance sites in a digital model generation method for invisible aligners based on traction force analysis, provided in a certain embodiment of the present invention. Figure 4 A schematic diagram of the force analysis of the second connecting unit in the digital model generation method for invisible orthodontic appliances based on traction force analysis provided in a certain embodiment of the present invention. Figure 1 ; Figure 5 A schematic diagram of the force analysis of the second connecting unit in the digital model generation method for invisible orthodontic appliances based on traction force analysis provided in a certain embodiment of the present invention. Figure 2 ; Figure 6 A schematic diagram of the force analysis of the second connecting unit in the digital model generation method for invisible orthodontic appliances based on traction force analysis provided in a certain embodiment of the present invention. Figure 3 ; Figure 7 This diagram illustrates the mechanical relationship analysis of the displacement direction force components, target displacement direction, and surface stress resultant force in a digital model generation method for invisible orthodontic appliances based on traction force analysis, provided for a certain embodiment of the present invention. Figure 7 (a) in the figure is a schematic diagram of the mechanical relationship analysis where the direction of the displacement force component is the same as the target displacement direction and the displacement force component is less than the resultant force of surface stress in the initial surface stress parameters; Figure 7 (b) in the diagram is a schematic diagram of the mechanical relationship analysis where the direction of the force component in the displacement direction is the same as the direction of the target displacement and the force component in the displacement direction is greater than the resultant force of the surface stress in the initial surface stress parameters; Figure 7 (c) in the diagram is a schematic diagram of the mechanical relationship analysis where the direction of the force component in the displacement direction is opposite to the direction of the target displacement. Figure 8 This is a schematic diagram of the module structure of a digital model generation system for invisible orthodontic appliances based on traction force analysis, provided in a certain embodiment of the present invention. Detailed Implementation

[0009] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0010] Example 1 See Figure 1 , Figure 1 This is a flowchart illustrating the steps of a method for generating a digital model of an invisible orthodontic appliance based on traction force analysis, according to a certain embodiment of the present invention; as shown below. Figure 1As shown, this embodiment of the invention proposes a method for generating a digital model of an invisible aligner based on traction force analysis, including steps 101 to 106, each step being as follows: Step 101: Based on the pre-acquired current dentition position and the preset orthodontic target, generate the target displacement direction, target rotation direction, and target dentition position; construct an initial aligner digital model and an initial traction hook digital model based on the target dentition position; Step 102: Select the non-overlapping portion of the current dentition position and the target dentition position to obtain the predicted implantation site for the micro-implant; simulate wearing the initial aligner digital model on the current dentition position, calculate the dentition impedance point at the current dentition position, obtain the traction hook height corresponding to the initial traction hook digital model based on the dentition impedance point and the preset orthodontic target, and connect the predicted implantation site for the micro-implant and the initial traction hook digital model based on the traction hook height to obtain the first connecting unit; Step 103: Based on the initial aligner digital model and the first connecting unit, match the initial surface stress parameters and the initial anchorage screw traction from the preset mechanical simulation parameter library. Force parameters: Based on a preset simulated treatment cycle, the current dentition position is simulated using initial surface stress parameters and initial anchorage screw traction force parameters to obtain the simulated dentition position; Step 104: Based on the simulated dentition position and the target dentition position, the displacement deviation and rotation deviation are calculated. Based on the target rotation direction, the initial anchorage screw traction force parameters are rematched from the preset mechanical simulation parameter library until the rotation deviation meets the preset rotation deviation requirement, thus obtaining the target anchorage screw traction force parameters; Step 105: Based on the target anchorage screw traction force parameters, the displacement direction force component is obtained. Based on the displacement direction force component and the target displacement direction, the initial surface stress parameters are rematched from the preset mechanical simulation parameter library until the displacement deviation meets the preset displacement deviation requirement, thus obtaining the target surface stress parameters; Step 106: Based on the target anchorage screw traction force parameters, a digital model of the target traction hook is obtained. Based on the target surface stress parameters, a digital model of the target aligner is obtained. Based on the target traction hook digital model and the target aligner digital model, a digital model of the invisible aligner is generated.

[0011] One specific implementation method involves using a cone-beam computed tomography (CBCT) scanner to acquire data on the hard tissue structures of the user's jawbone and tooth roots, followed by an intraoral scanner to acquire surface tissue morphology data of the user's tooth crowns and gingiva. Ultrasonic imaging is also used to obtain periodontal soft tissue thickness data. A three-dimensional digital model of the oral cavity is constructed using a multimodal registration algorithm. Based on the generated three-dimensional digital model, the current dentition position is determined. Then, combined with the orthodontic treatment plan determined after communication between the user and the clinician, such as improving tooth alignment, adjusting occlusion, and closing gaps, a preset treatment goal is obtained from the corresponding treatment plan. A path planning algorithm is used to generate a predicted movement path for the teeth to move from the current position to the target position. Then, based on the current dentition position and the predicted movement path, the target dentition position, target displacement direction, and target rotation direction are output. Finally, a shell enclosing each tooth is generated at the target dentition position, and initial traction hook attachment points are set on the outer surface of the shell, thus obtaining the initial digital model of the orthodontic appliance and the initial digital model of the traction hook.

[0012] Next, the current dentition position and the target dentition position are registered. The non-overlapping area is taken as the predicted implantation site for the micro-implant. Typically, this non-overlapping area comprises several regions. The predicted implantation site is determined based on the tooth position requiring overall movement or torque control. This predicted implantation site is usually set on the labial side of the second premolar to the first molar, 10-13 mm from the marginal ridge. Then, the initial digital model of the orthodontic appliance is simulated and worn in the current dentition position. Next, the dentition impedance points at the current dentition position are calculated. Specifically, the impedance center of each tooth is first calculated, and then a weighted average algorithm is used to combine the impedance centers of each tooth into a single dentition impedance point. Based on the dentition impedance points and the preset treatment target, the relationship between the traction hook height and the dentition impedance points is obtained. The relationship between height and dentition resistance points can lead to different orthodontic effects. The final determination of the initial traction hook height corresponds to the digital model of the initial traction hook. Based on this height, the predicted implantation site of the micro-implant and the initial traction hook digital model are connected to obtain the first connecting unit. Specifically, the first connecting unit is obtained by connecting the predicted implantation site of the micro-implant and the initial traction hook digital model. The initial traction hook digital model is set on the initial traction hook attachment point, which is set on the initial orthodontic appliance digital model. Generally, for the molar distalization stage, a traction point can be designed distally from the canine, with a height of 5-7 mm, using the first connecting unit for distal traction. For the anterior retraction stage, a traction point can be designed between the lateral incisor and canine, with a height of 5-7 mm, using the first connecting unit for distal traction. It is worth mentioning that if the predicted implantation site of the micro-implant becomes loose or falls off during the correction process, it is necessary to obtain a new predicted implantation site. Generally, a circle with a radius of 2 mm is drawn with the original predicted implantation site as the center, and the predicted implantation site of the micro-implant is re-determined within the range of this circle.

[0013] Next, from the historical orthodontic case database, cases with good treatment results and complete data are selected. The historical oral 3D digital models of these cases and their corresponding historical appliance models are extracted. The historical appliance models are mechanically simulated using the finite element method to obtain the corresponding preset mechanical simulation parameter library. Then, the initial surface stress parameters and initial anchorage screw traction force parameters are matched from the preset mechanical simulation parameter library to perform the mechanical simulation application process on the initial appliance digital model. After the simulated treatment is performed through mechanical simulation and meets the preset simulated treatment cycle, the simulated dentition position is generated.

[0014] Then, it is determined whether there is any displacement or rotational deviation between the generated simulated dentition position and the target dentition position. If there is no displacement or rotational deviation, the currently matched initial surface stress parameters and initial anchorage screw traction force parameters can be directly used as the target surface stress parameters and target anchorage screw traction force parameters to obtain the target traction hook digital model and the target aligner digital model, thus generating the invisible aligner digital model. If there is a displacement or rotational deviation between the simulated dentition position and the target dentition position, the initial anchorage screw traction force parameters are first rematched from the preset mechanical simulation parameter library according to the target rotation direction, and the rematched initial anchorage screw traction force is used. The parameters are adjusted for the rotational deviation until the rotational deviation meets the preset rotational deviation requirements. The currently matched initial anchorage pin traction force parameters are recorded as the target anchorage pin traction force parameters. Then, in order to fully consider the influence of the displacement direction on the rotational direction adjustment, the anchorage pin traction force in the target anchorage pin traction force parameters is decomposed into displacement direction force components in the target displacement direction. Then, it is determined whether the direction of the displacement direction force components is the same as or opposite to the target displacement direction. The relationship between the displacement direction force components and the resultant force of the surface stress in the initial surface stress parameters is also considered. In this way, the initial surface stress parameters are rematched from the preset mechanical simulation parameter library until the displacement deviation meets the preset displacement deviation requirements, and the target surface stress parameters are obtained.

[0015] Finally, the traction force parameters of the target anchorage nail determine the traction hook height of the initial traction hook digital model, thus obtaining the target traction hook digital model. Then, based on the target surface stress parameters, the corresponding orthodontic digital model is obtained as the target orthodontic digital model. Finally, based on the target traction hook digital model and the target orthodontic digital model, the invisible orthodontic digital model is generated. In this embodiment, the surface stress parameters include not only the surface stress itself, but also the digital model structure of the orthodontic appliance corresponding to the surface stress. The digital model structure of the orthodontic appliance corresponding to the surface stress is determined from historical experience. If the model is not suitable, existing model design methods can be used to iteratively optimize the model, which will not be elaborated here. Similarly, the anchorage screw traction force parameters include not only the anchorage screw traction force, but also the corresponding traction hook height and the tightness of the connection between the micro-implant and the traction hook. For example, the connection can be a rubber band. By adjusting the tightness of the rubber band between the micro-implant and the traction hook, the magnitude of the anchorage screw traction force can be adjusted accordingly. The tightness of the rubber band and the magnitude of the anchorage screw traction force are also learned from historical experience. If they are not suitable, existing model design methods can be used to iteratively optimize the model, which will not be elaborated here.

[0016] In the above scheme, an initial digital model of the orthodontic appliance and the first connecting unit are first constructed. The method of matching the corresponding mechanical parameters from the preset mechanical simulation parameter library and applying them through simulation is adopted instead of the traditional process of mechanical analysis after model optimization design. The displacement and rotational deviation between the simulated dentition position and the target dentition position are calculated. Then, the mechanical simulation application process is divided into rotational direction adjustment and displacement direction adjustment. Traction force analysis is introduced to first apply mechanical simulation in the rotational direction until the rotational deviation meets the preset rotational deviation requirement, and the traction force parameter of the target anchorage screw is obtained. Then, the displacement direction force component is obtained from the traction force parameter of the target anchorage screw, and the affected initial surface stress parameter is compensated. The initial surface stress parameter is then rematched until the displacement deviation meets the preset displacement deviation requirement, and the target surface stress parameter is obtained. Finally, the digital model of the invisible orthodontic appliance is generated, so as to realize the process of considering the possible deviation in the displacement direction after the rotational direction adjustment and making further adjustments.

[0017] This invention proposes a method for generating digital models of invisible aligners based on traction force analysis. It employs a method that considers potential deviations in the displacement direction after adjusting the rotation direction and makes further adjustments. To ensure that the resultant force in the rotation and displacement directions remains constant during treatment, after obtaining the traction force parameters of the target anchorage screw, the displacement force component is acquired and re-matched to the initial surface stress parameters. Thus, by analyzing the traction force, the influence of the rotation direction adjustment on the displacement direction deviation is fully considered, demonstrating the synergy between displacement and rotation direction control. Compared to existing technologies, this method can simultaneously meet the treatment goals in both displacement and rotation directions, ensuring the accuracy of tooth movement control during treatment and improving the reliability of orthodontic treatment.

[0018] A preferred embodiment includes step 101, comprising: acquiring multimodal oral data using a preset data acquisition device to obtain oral CBCT image data, 3D optical surface scan data, and periodontal tissue ultrasound imaging data; aligning the oral CBCT image data, 3D optical surface scan data, and periodontal tissue ultrasound imaging data in a preset spatial coordinate system based on a preset multimodal registration algorithm, and fusing tooth morphology information, root position information, intraoral soft tissue surface morphology information, and jawbone morphology information from the oral CBCT image data, 3D optical surface scan data, and periodontal tissue ultrasound imaging data in the preset spatial coordinate system to construct a three-dimensional digital model of the oral cavity; and obtaining the current dentition based on the three-dimensional digital model of the oral cavity. Position; Based on the current dentition position and the preset orthodontic goal, generate a predicted movement path from the current dentition position to the dentition position corresponding to the preset orthodontic goal; divide the orthodontic process into several path sequences according to the predicted movement path, and assign each path sequence to a predicted dentition stage to obtain several predicted dentition stages; based on the preset historical orthodontic prediction model and several predicted dentition stages, generate the target dentition position, the target displacement direction of the current dentition position, and the target rotation direction of the current dentition position for each predicted dentition stage according to the current dentition position and the predicted movement path of each predicted dentition stage; construct the initial digital model of the appliance and the initial digital model of the traction hook based on the target dentition position.

[0019] One preferred implementation method is described in [reference]. Figure 2 , Figure 2 This is a data fusion diagram illustrating a method for generating a digital model of an invisible aligner based on traction force analysis, provided in a certain embodiment of the present invention; as shown. Figure 2As shown, CBCT scanning equipment is used to collect data on the hard tissue structures of the user's jawbone and tooth roots, and the oral CBCT image data is output in DICOM format; then an intraoral scanner is used to collect surface tissue morphology data of the user's tooth crown and gingival surface, and the 3D optical surface scanning data is usually output in STL or PLY format; it is also necessary to obtain periodontal soft tissue thickness data through ultrasound imaging equipment to obtain soft tissue data such as gingiva and periodontal ligament, that is, periodontal tissue ultrasound imaging data.

[0020] In one interpretable example, firstly, the oral CBCT image data, 3D optical surface scan data, and periodontal tissue ultrasound imaging data are preprocessed, including noise reduction and contrast enhancement. After data preprocessing, the oral CBCT image data, 3D optical surface scan data, and periodontal tissue ultrasound imaging data are input into medical image processing software. Based on a multimodal registration algorithm using feature points, anatomical feature points of the teeth, such as cusps and sockets, are extracted from the oral CBCT image data and 3D optical surface scan data, and corresponding feature points are found in the periodontal tissue ultrasound imaging data. Then, using the tangent of the maxillary sinus as a reference, the image data are aligned in a three-dimensional spatial coordinate system according to the corresponding feature points, ensuring that each image data is registered in the three dimensions of row, column, and thickness. Then, in the three-dimensional spatial coordinate system, existing mature image fusion technology is used to fuse the tooth morphology information, root position information, intraoral soft tissue surface morphology information, and jawbone morphology information in each image. For example, in this embodiment, a weighted average fusion method is used to ensure that the fused model retains the accurate structure of hard tissues and contains detailed information about soft tissues. Finally, 3D reconstruction software is used to process the fused data and construct a 3D digital model of the oral cavity. In this embodiment, the 3D reconstruction software can be Mimics or Geomagic, etc. The 3D digital model of the oral cavity should include complete information on teeth, tooth roots, jawbone, and intraoral soft tissues, such as... Figure 2 The shown three-dimensional digital model of the oral cavity is used for subsequent design of digital models of orthodontic appliances.

[0021] Then, in the 3D digital model of the oral cavity, image segmentation technology is used to automatically identify and extract the positional information of each tooth, including the crown, root, and axial direction. Based on the anatomical features and relative positional relationships of the teeth, the overall arrangement of the current dentition is determined, i.e., the current dentition position, which includes the degree of crowding and misalignment. In this embodiment, the preset orthodontic goal is usually determined after communication between the user and the clinician, such as improving tooth alignment, adjusting occlusion, and closing gaps. The preset orthodontic goal is obtained from the corresponding orthodontic plan. Then, based on the current dentition position and the preset orthodontic goal, a path planning algorithm is used to generate a predicted movement path for the teeth to move from the current position to the target position. Path planning algorithms can include A* and Dijkstra's algorithm. It is worth noting that when applying path planning algorithms, the biological characteristics of the oral cavity, such as the tooth movement speed and the limiting direction of tooth movement, should be considered. Then, the current dentition position and the predicted movement path are input into the preset historical orthodontic prediction model to predict the target dentition position. The preset historical orthodontic prediction model is a model trained from several historical orthodontic cases. This model can predict the orthodontic effect based on the current dentition position and the predicted movement path. Therefore, after inputting the current dentition position and the predicted movement path, it can combine the experience of historical orthodontic cases to infer and generate the target dentition position, the target displacement direction of the current dentition position, and the target rotation direction of the current dentition position corresponding to the three-dimensional digital model of the oral cavity.

[0022] Finally, based on the target dentition position obtained through reasoning, an initial digital model of the orthodontic appliance and an initial digital model of the traction hook are constructed in 3D modeling software. The initial digital model of the orthodontic appliance is obtained by constructing a shell on each tooth and setting key structures such as the attachment point of the traction hook at the corresponding tooth position according to the target dentition position. The initial digital model of the orthodontic appliance can reflect the shape and arrangement of each tooth at the target position. The initial digital model of the traction hook is set on the attachment point of the traction hook, and the traction hook corresponding to the initial digital model of the traction hook has an initial height, and the height of the traction hook can be adjusted according to the preset orthodontic goal.

[0023] A further explanation of a preferred embodiment: Since orthodontic treatment is a long-term process due to limitations in tooth movement speed, this embodiment proposes to discretize the predicted movement path into several dentition stages to improve treatment effectiveness. For example, each stage may have a tooth movement distance of 0.25 mm. In each dentition stage, the target dentition position of the previous stage is used as the current dentition position. The preset treatment target for the current dentition stage is input into a preset historical treatment prediction model to generate the predicted movement path, the target dentition position, the target displacement direction, and the target rotation direction for the current dentition position. Based on the target dentition position, an initial digital model of the appliance and an initial digital model of the traction hook for the current dentition stage are constructed. This process is repeated to obtain the initial digital models of the appliance and the traction hook for all dentition stages.

[0024] In the above scheme, multimodal oral data is collected, and a three-dimensional digital model of the oral cavity is constructed using existing algorithms. This model integrates jawbone and tooth root information from CBCT, detailed crown morphology from intraoral scanning, and soft tissue data from ultrasound, providing a reliable data foundation for subsequent orthodontic appliance design. Furthermore, the processing and analysis of multimodal data provides various modal features. Additionally, by combining the current dentition position and the preset treatment target to predict the dentition movement path, a historical treatment prediction model is introduced. Based on the current dentition position and the predicted movement path, the most biomechanically consistent target dentition position is predicted from historical data, and a corresponding initial digital model of the orthodontic appliance is constructed. The target dentition position is predicted through theoretical prediction combined with historical experience learning, providing a reliable data foundation for subsequent mechanical simulation. This approach solves the problems of insufficient accuracy and missing information in models based on a single data source, enables personalized customization of the oral cavity, improves the reliability of the digital model design of the orthodontic appliance, and ultimately enhances the reliability of orthodontic treatment.

[0025] In a preferred embodiment, during step 102, the pre-setting process of the pre-set historical orthodontic prediction model includes: acquiring several historical orthodontic data sets; from these data sets, acquiring the historical initial dentition position, the historical dentition position movement path, the historical target dentition position, the target displacement direction, and the target rotation direction; using the historical target dentition position as the output target, and using the historical initial dentition position, the historical dentition position movement path, the target displacement direction, and the target rotation direction as the input training set, training the pre-set deep learning model to obtain the pre-set historical orthodontic prediction model.

[0026] One preferred implementation method involves first constructing a historical case dataset. This is achieved by collecting historical orthodontic data from a large number of completed orthodontic treatment cases. The data needs to be de-identified to protect patient privacy. Each case's data package should include: a pre-treatment 3D digital model of the oral cavity, data on each planned or actual tooth movement path during treatment, a post-treatment 3D digital model of the oral cavity, the planned or actual tooth displacement direction and rotation direction during each planned or actual tooth rotation direction during treatment. The data is then cleaned to remove cases with abnormal movement paths or poor results. A high-quality historical orthodontic dataset is formed. In this embodiment, the three-dimensional digital model of the oral cavity before treatment represents the initial position of the dentition; the data of each step of tooth movement path planned or actually executed during treatment represents the historical dentition position movement path; the three-dimensional digital model of the oral cavity after treatment represents the historical target dentition position; the direction of tooth displacement for each step planned or actually executed during treatment represents the target displacement direction of the historical dentition position corresponding to each historical orthodontic data; and the direction of tooth rotation for each step planned or actually executed during treatment represents the target rotation direction of the historical dentition position corresponding to each historical orthodontic data.

[0027] Next, data preprocessing and feature engineering were performed on the historical orthodontic dataset. The historical initial dentition position and historical dentition movement path of each case were used as the input features X of the model. The initial dentition position can be represented as the coordinate matrix of all tooth landmarks, and the movement path can be represented as the sequence of movement transformation matrices at each stage. The historical target dentition position was also represented as the landmark coordinate matrix and used as the output target Y of the model. All historical orthodontic data were normalized to eliminate the influence of dimensions. A deep learning model was designed and trained, using an architecture that integrates a convolutional neural network (CNN) and a long short-term memory network (LSTM). The CNN branch was used to process the static initial 3D dentition model and extract its spatial structure features, while the LSTM branch was used to process the dynamic tooth movement path sequence and capture its temporal dependence. After the output features of the two branches were fused, the final target dentition position was predicted by regression through a fully connected layer. The loss function was the mean squared error (MSE) between the predicted target position and the true target position. The Adam optimizer was used to train the model on the training set, and the performance was monitored on the validation set to prevent overfitting.

[0028] Finally, the trained model is evaluated using an independent test set, and the average error between the predicted and actual positions is calculated. Once the model reaches the preset accuracy requirement, it is deployed as a preset historical orthodontic prediction model. The preset accuracy requirement can be set to a crown center point error of less than 0.2 mm. In this embodiment, at each orthodontic stage, the patient's current dentition position and predicted movement path are input into the preset historical orthodontic prediction model. This yields the target dentition position, target displacement direction, and target rotation direction for each predicted dentition stage, which conforms to biomechanical principles and is more likely to be achieved.

[0029] In the above scheme, the experience of each historical orthodontic case is learned from a number of historical orthodontic data. The initial dentition position, movement path, target displacement direction and target rotation direction are used as inputs, and the target dentition position is used as the output for training. In this way, the target dentition position and target movement direction that conform to the biomechanical law can be output according to the actual situation of the current case. The historical experience is quantified into a reusable algorithm model. In this way, when the preset historical orthodontic prediction model is applied in the future, the target dentition position can be predicted according to the input initial dentition position and predicted movement path, reducing the inaccuracy of human subjective judgment, improving the reliability of the digital model design of the orthodontic appliance, and thus improving the reliability of orthodontic treatment.

[0030] A preferred embodiment involves constructing an initial digital model of the orthodontic appliance and an initial digital model of the traction hook, based on the target dentition position. This includes: obtaining the displacement and rotation angle of each tooth from the current dentition position to the target dentition position based on the current dentition position, the target displacement direction of the current dentition position, and the target rotation direction of the current dentition position; generating a tooth-position enclosure shell along the outer surface of each tooth position with a preset extension distance, based on the target dentition position; setting initial traction hook attachment points on the outer surface of the tooth-position enclosure shell according to the displacement and rotation angle of each tooth position in the target dentition position, and constructing an initial traction hook digital model based on the initial traction hook attachment points; and constructing a negative cavity complementary to the crown morphology on the inner surface of the tooth-position enclosure shell according to the displacement and rotation angle of each tooth position in the target dentition position, thereby constructing an initial digital model of the orthodontic appliance corresponding to the target dentition position.

[0031] One preferred implementation involves comparing the current dentition position with the target dentition position to calculate the required movement parameters for each tooth, including the displacement and rotation angle at each tooth position. These parameters define the rigid body transformation that the tooth needs to complete. It is worth noting that the variables involved in orthodontic treatment are complex, including variables such as intrusion and elongation. In actual treatment, intrusion and elongation affect the displacement and rotation angle of the teeth. Therefore, these variables can also be categorized as displacement in the displacement direction and rotation angle in the rotation direction. In this embodiment, all types of variables can be implemented using the technical solution proposed in this invention to fully consider the displacement in the displacement direction and the rotation angle in the rotation direction. The relationship between them is then established; then, using the outer surface of the crowns of all teeth in the target dentition position as a reference surface, the isometric surface operation of CAD software is used to offset outward by a distance equal to the thickness of the orthodontic appliance material. This distance can usually be set to 0.75 mm to generate a continuous and smooth tooth position wrapping shell. This shell is the inner surface shape of the orthodontic appliance. Then, the initial traction hook attachment point is set on the tooth position wrapping shell. The function of the traction hook is to connect anchorage devices such as micro-implants and provide additional orthodontic force. According to biomechanical principles, the optimal attachment position of the traction hook is located on the outer surface of the crown wrapping shell of the tooth position where the movement mode needs to be controlled. The tooth positions where the movement mode needs to be controlled usually include those that require overall movement or torque control.

[0032] It is worth mentioning that the optimal attachment position of the traction hook should provide the most effective force vector to achieve the desired tooth movement. For example, for upper anterior teeth requiring indentation and retraction, the traction hook is usually placed in the center of the crown. A 3D model of a raised platform or hook-like structure is created at this location, and this model is structurally fused with the tooth-position enclosure shell through Boolean addition. Finally, Boolean subtraction is performed on the crown portion of the target dentition position and the inner surface of the tooth-position enclosure shell, thereby forming a negative cavity inside the appliance that perfectly matches the crown shape. This negative cavity ensures a tight fit between the appliance and the teeth when worn, allowing the rebound force generated after the appliance undergoes elastic deformation to be accurately and efficiently transmitted to the teeth. Thus, the final generated initial digital model of the appliance includes a complete 3D digital model of the internal negative cavity, the external tooth-position enclosure shell structure, and the traction hook attachment point. The initial traction hook digital model is constructed based on the position of the traction hook attachment point, and the traction hook corresponding to the initial traction hook digital model has an initial height, which can be adjusted according to the preset orthodontic goals.

[0033] In the above scheme, a shell is first constructed to enclose the tooth position at the target dentition location. Then, the attachment points of the traction hooks are marked according to the movement parameters of each tooth position to provide a data basis for subsequent mechanical analysis. The attachment points of the traction hooks determine the position of the initial traction hook digital model. The height of the traction hooks corresponding to the initial traction hook digital model can be used to apply traction force and provide a structural basis for subsequent mechanical adjustments. Finally, a negative cavity that complements the morphology is constructed. The negative cavity is used to position the orthodontic appliance and facilitate the effective transmission of force. In this way, the initial orthodontic appliance digital model and the initial traction hook digital model are constructed, providing a data basis for subsequent biomechanical characteristic analysis and helping to improve the reliability of the orthodontic appliance digital model design.

[0034] In a preferred embodiment, step 103, the pre-setting process of the pre-set mechanical simulation parameter library includes: based on several historical orthodontic data, obtaining a historical three-dimensional digital model of the oral cavity, a corresponding historical digital model of the orthodontic appliance, and a historical digital model of the traction hook from the historical orthodontic data; based on a pre-set simulation algorithm, dividing the historical three-dimensional digital model of the oral cavity and the corresponding historical digital model of the orthodontic appliance into several grids; based on historical orthodontic goals, solving the stress distribution generated between the inner surface of the historical digital model of the orthodontic appliance and the tooth surface of the historical three-dimensional digital model of the oral cavity in each grid; obtaining surface stress parameters based on the historical digital model of the orthodontic appliance and the stress distribution; traversing several grids, and according to the historical orthodontic goals... The treatment target and historical traction hook digital model are used to obtain historical micro-implant sites, historical traction hook attachment points, and historical traction hook heights. Based on the historical traction hook attachment points and historical traction hook heights, the position of the historical traction hook is obtained. Based on the position of the historical traction hook, the historical micro-implant sites and historical traction hooks are connected to obtain the second connecting unit. Based on the historical oral cavity three-dimensional digital model, the resistance center of each tooth in the dentition is calculated. Based on the resistance center of each tooth, the dentition impedance point is solved, and the anchorage screw traction force is solved based on the second connecting unit. Based on the dentition impedance point and the anchorage screw traction force, the anchorage screw traction force parameters are obtained. The surface stress parameters and the anchorage screw traction force parameters are integrated into a preset mechanical simulation parameter library.

[0035] One preferred implementation involves selecting cases with good treatment outcomes and complete data from a historical orthodontic case database, extracting historical three-dimensional digital models of the oral cavity and their corresponding historical orthodontic appliance digital models from these cases, and importing the historical orthodontic appliance digital models into finite element analysis software. Precise tetrahedral or hexahedral meshes are then created for the teeth, appliances, periodontal ligament, and jawbone in the historical orthodontic appliance digital models. The meshes are refined for contact areas and stress concentration areas. In this embodiment, the mesh size can be set to 0.2 mm to 0.5 mm. The material properties of the finite element model are then set in the finite element analysis software. The material parameter settings for the finite element model in this embodiment are shown in Table 1. Table 1 Material Parameters for Finite Element Model Then, the frictional contact between the crown and the inner surface of the appliance is defined, with the friction coefficient generally set to 0.2. Next, the historical digital model of the appliance is subjected to displacement loading according to its design deformation, and the stress distribution between the inner surface of the historical digital model of the appliance and the tooth contact surface is solved. The stress cloud map data of the entire dental surface is extracted, as well as the stress values ​​of key points such as the crown center and marginal ridges. The surface stress and the corresponding historical digital model of the appliance are stored as a surface stress parameter set.

[0036] In the historical orthodontic appliance model, historical micro-implant sites, historical traction hook attachment points, and historical traction hook heights are identified. A second connecting unit, representing a rubber chain or elastic band, is established between the historical micro-implant sites and historical traction hooks. A resultant force per unit displacement is applied to this connecting unit. Since this embodiment of the invention needs to consider the height of the historical traction hook, the dental impedance sites need to be solved using a three-dimensional digital model of the oral cavity. Then, the second connecting unit is considered as an anchorage device, and the stress-strain distribution of the teeth and surrounding tissues, as well as the tooth movement trend, are solved under the traction force of the anchorage screw. Finally, based on the relative position of the anchorage screw traction force and the dental impedance sites, the optimal traction force magnitude and direction required to achieve specific tooth movement are recorded. These parameters, along with the corresponding traction hook heights and the relative positions of the dental impedance sites and different traction hook heights, are stored as an anchorage screw traction force parameter set. Finally, all surface stress parameter sets, anchorage screw traction force parameter sets, and corresponding case information are associated and indexed to form a structured and queryable pre-set mechanical simulation parameter library.

[0037] In this embodiment, since the traction force generated by the micro-implant anchorage is produced by the deformation of the traction spring, the resultant force of the anchorage pin traction force can be obtained. Unlike existing mature force analysis processes, this invention proposes a force analysis process that considers the height of the traction hook and dynamic impedance calculations. For details, see [link to relevant documentation]. Figure 3 , Figure 3 This is a schematic diagram illustrating the calculation process of dentition impedance sites in a digital model generation method for invisible aligners based on traction force analysis, provided in a certain embodiment of the present invention; as shown. Figure 3 As shown, the calculation process for dental arch impedance sites includes: S1, obtaining the position of the dental arch curve based on the spatial coordinate system of the three-dimensional digital model of the oral cavity; S2, determining the resistance center coordinates of each tooth in the dental arch based on the position of the dental arch curve; S3, merging the resistance center coordinates of all teeth into a single dental arch impedance site by weighted averaging of the resistance center coordinates of each tooth.

[0038] One specific explanation involves using the spatial coordinate system of the three-dimensional digital model of the oral cavity. A continuous and smooth curve connecting the edges of the teeth represents the position of the dental arch curve. Based on the position of the dental arch curve, the coordinates of the resistance center of each tooth in the dentition are determined. After obtaining the coordinates of the resistance center of each tooth, the composite resistance center of the entire dental arch is further obtained, resulting in the dental arch impedance point. The specific steps are as follows: Since all teeth are rigidly connected to form a whole, the resistance center of this whole can be regarded as a weighted average of the resistance centers of each tooth. Finally, by averaging the coordinates of the resistance centers of each tooth, the coordinates of the resistance centers of all teeth are merged into a single point, namely the dental arch impedance point. Since the root surface area is directly related to the amount of periodontal supporting tissue, a common and feasible example in orthodontic biomechanics is to use the root surface area as the weight for weighted averaging. The above execution scheme simplifies the calculation of the overall resistance center of the dentition into a complex shape centroid calculation process, greatly reducing the difficulty of resistance center calculation.

[0039] Finally, by solving for the dental impedance sites and the anchorage screw traction force (the magnitude of the anchorage screw traction force can be obtained using existing mature algorithms), and then analyzing the relative positions of the dental impedance sites and the anchorage screw traction force, the anchorage screw traction force parameters are obtained. The specific process is as follows: See [link to relevant documentation]. Figure 4 , Figure 5 and Figure 6 , Figure 4 A schematic diagram of the force analysis of the second connecting unit in the digital model generation method for invisible orthodontic appliances based on traction force analysis provided in a certain embodiment of the present invention. Figure 1 ; Figure 5 A schematic diagram of the force analysis of the second connecting unit in the digital model generation method for invisible orthodontic appliances based on traction force analysis provided in a certain embodiment of the present invention. Figure 2 ; Figure 6 A schematic diagram of the force analysis of the second connecting unit in the digital model generation method for invisible orthodontic appliances based on traction force analysis provided in a certain embodiment of the present invention. Figure 3 ;like Figure 4 , Figure 5 and Figure 6 As shown, the yellow sites near the tooth root are the micro-implant sites, the yellow sites on the tooth surface are the attachment points of the traction hooks, the black devices with different heights are the traction hooks 1, the red straight line simulates the second connecting unit 2 connecting the micro-implant and the traction hook 1, and the orange sites are the dental impedance sites. Then, force analysis is performed on the traction hook 1, and the light green force along the direction of the second connecting unit 2 is the anchorage screw traction force. The dark green force is the traction force of the anchor nail. The decomposition force, among which, Characterized as force components in the displacement direction; Figure 4 , Figure 5and Figure 6 These represent three different traction hook heights. When the dental impedance point is located in the direction of the anchorage screw traction force, tooth retraction can be achieved, such as... Figure 4 As shown in the diagram; when the dental impedance point is higher than the direction of the anchorage screw traction force, in addition to achieving dental retraction, it can also pull the dental arch to perform a counterclockwise rotational movement, such as... Figure 5 As shown in the diagram; when the dental resistance point is below the direction of the anchorage screw traction force, in addition to achieving dental retraction, it can also pull the dental arch to perform clockwise rotational movement, such as... Figure 6 The situation is illustrated below. This demonstrates that different orthodontic effects can be achieved by designing different traction hook heights.

[0040] As the above analysis shows, the relative positions of dentition impedance points and different traction hook heights affect the direction of tooth displacement. Therefore, the anchorage screw traction force parameters include: the magnitude of the anchorage screw traction force, the corresponding traction hook height, and the relative positions of dentition impedance points and different traction hook heights. Thus, at different stages of dentition displacement, tooth movement can be achieved by solving for the dentition impedance points and adjusting the traction hook height according to the dentition displacement requirements. This eliminates the need for repeated adjustments to the structure of the orthodontic appliance digital model and repeated collection of user data, thereby improving the reliability of the orthodontic appliance digital model design and consequently, the reliability of orthodontic treatment. It is worth mentioning that, for the sake of simplicity... Figure 4 , Figure 5 and Figure 6 The force analysis in this paper is only an example to explain the relative positions of the tooth row resistance points and different traction hook heights, and does not represent a schematic of the actual traction force.

[0041] In the aforementioned scheme, a pre-defined mechanical simulation parameter library was constructed. Using simulation methods such as finite element analysis, mechanical calculations were performed on the appliances and second connecting units in historical orthodontic cases, extracting surface stress parameters and anchorage screw traction force parameters. This pre-defined mechanical simulation parameter library incorporates mechanical experience from numerous clinical cases, including stress distribution and traction force configuration under different treatment stages and tooth movement patterns. In actual design, mechanical parameters similar to those of the current case can be quickly matched from this pre-defined mechanical simulation parameter library, improving simulation efficiency and accuracy. Therefore, by introducing a biomechanical characteristic simulation mechanism and considering biomechanical characteristics during the design process of the appliance digital model, the reliability of the appliance digital model design is improved, thereby enhancing the reliability of orthodontic treatment.

[0042] In a preferred embodiment, step 103 includes: matching initial surface stress parameters and initial anchorage screw traction force parameters from a preset mechanical simulation parameter library, setting the initial surface stress parameters in the initial orthodontic appliance digital model, and setting the initial anchorage screw traction force parameters in the first connecting unit; based on a preset simulated treatment cycle, simulating the application of the initial surface stress parameters and initial anchorage screw traction force parameters to the current dentition position through the initial orthodontic appliance digital model and the first connecting unit; and obtaining the simulated dentition position corresponding to the preset simulated treatment cycle each time a mechanical simulation application is completed.

[0043] One preferred implementation involves importing the initial orthodontic appliance digital model and the three-dimensional digital model of the oral cavity into finite element analysis software based on the current dentition position. The software then matches the corresponding initial surface stress parameters from a preset mechanical simulation parameter library and sets these parameters on the initial orthodontic appliance digital model. Next, it matches the initial anchorage screw traction force parameters from the preset mechanical simulation parameter library and sets them on the first connecting unit. Finally, it executes a simulated orthodontic process according to a preset simulated treatment cycle. After the simulation is complete, the simulated dentition position corresponding to the preset simulated treatment cycle is output. The simulated dentition position represents the position the teeth will move to after simulated treatment under the action of the initial orthodontic appliance digital model, initial surface stress parameters, the first connecting unit, and the initial anchorage screw traction force parameters. The preset simulated treatment cycle typically corresponds to each treatment stage; that is, one treatment stage corresponds to one simulated treatment cycle.

[0044] In the above scheme, initial surface stress parameters and initial anchorage screw traction force parameters are matched and set in the corresponding structures from a preset mechanical parameter library. Then, simulated orthodontic treatment is performed on the current dentition position according to a preset simulated treatment cycle, gradually obtaining the simulated dentition position at each stage. This standardizes and stages the complex biomechanical simulation process, replacing the traditional inefficient model reconstruction and iterative analysis process with parameterized settings. After each simulation, the corresponding tooth position changes can be obtained, facilitating timely evaluation of treatment effects and adjustment of corresponding parameters. This helps improve the reliability of the digital model design of the orthodontic appliance, thereby improving the reliability of orthodontic treatment.

[0045] In a preferred embodiment, step 104 includes: obtaining displacement and rotational deviations by simulating the position of the dentition and the position of the target dentition; if the rotational deviation does not meet the preset orthodontic target, then rematching the initial anchorage screw traction force parameters from the preset mechanical simulation parameter library according to the target rotation direction, and adjusting the first connecting unit according to the rematched initial anchorage screw traction force parameters until the rotational deviation meets the preset rotational deviation requirement, wherein the initial traction hook digital model is set on the initial traction hook attachment point, and the initial traction hook attachment point is set on the initial orthodontic appliance digital model; adjusting the first connecting unit includes: adjusting the traction hook height corresponding to the initial traction hook digital model and / or adjusting the position of the initial traction hook attachment point; if the rotational deviation meets the preset rotational deviation requirement, then outputting the currently matched initial anchorage screw traction force parameters as the target anchorage screw traction force parameters.

[0046] In one preferred implementation, the simulated dentition position is three-dimensionally overlapped and registered with the target dentition position. The deviation values ​​of each tooth in the displacement and rotation directions are calculated, i.e., displacement deviation and rotation deviation. First, it is determined whether the current initial traction hook digital model needs optimization and adjustment by using a preset rotation deviation requirement. Typically, this preset rotation deviation requirement is set to a rotation deviation of <1°. If the rotation deviation does not meet the preset rotation deviation requirement, it indicates that the initial orthodontic appliance digital model does not control the torque of the teeth well. In this case, it is necessary to rematch the anchorage screw traction force parameters and obtain the connection relationship of the first connecting unit in the initial orthodontic appliance digital model corresponding to the rematched anchorage screw traction force parameters. That is, adjust the traction hook height and / or adjust the attachment point position of the initial traction hook digital model to change the force application point and lever arm, thereby controlling the tooth torque. In this embodiment, the first connecting unit is obtained by connecting the micro-implant predicted implantation site and the initial traction hook. The initial traction hook is set on the initial traction hook attachment point, which is set on the initial orthodontic appliance digital model. After iteratively optimizing and adjusting the connection relationship of the first connecting unit, if the rotation deviation meets the preset rotation deviation requirement, the currently matched anchor nail traction force parameter is output as the target anchor nail traction force parameter.

[0047] In the above scheme, when the detected rotational deviation does not meet the requirements, the traction force parameters of the anchorage screw are rematched from the preset mechanical simulation parameter library, and the height of the traction hook or the position of the attachment point are adjusted accordingly to optimize the mechanical effect of the first connecting unit. Thus, by analyzing the traction force to generate this adjustment mechanism, the rotational torque on the teeth can be accurately controlled, achieving correction of rotational movements such as tilting and twisting. Furthermore, by iteratively adjusting the traction hook structure to gradually approach the preset rotational deviation requirements, the accuracy and stability of rotational correction are ensured, which helps improve the reliability of the digital model design of the orthodontic appliance, thereby improving the reliability of orthodontic treatment.

[0048] A preferred embodiment includes step 105, comprising: based on the target anchorage pin traction force parameters, decomposing the target anchorage pin traction force in the target displacement direction using a preset force decomposition algorithm to obtain displacement direction force components; if the direction of the displacement direction force component is the same as the target displacement direction and the displacement direction force component is less than the resultant surface stress in the initial surface stress parameters, then calculating the difference between the resultant surface stress in the initial surface stress parameters and the displacement direction force component to obtain a first matching value, and re-matching surface stress parameters from a preset mechanical simulation parameter library that are equal in magnitude to the first matching value and have the same direction as the target displacement until the displacement deviation meets the preset displacement deviation requirement; if the direction of the displacement direction force component is the same as the target displacement direction and the displacement direction force component is greater than or equal to the resultant surface stress in the initial surface stress parameters... If the displacement direction force component is opposite to the target displacement direction, the difference between the force component in the displacement direction and the resultant force of the surface stress in the initial surface stress parameters is calculated to obtain a second matching value. Then, surface stress parameters equal in magnitude to the second matching value and opposite in direction to the target displacement are rematched from the preset mechanical simulation parameter library until the displacement deviation meets the preset displacement deviation requirement. If the displacement direction force component is opposite to the target displacement direction, the sum of the resultant force of the surface stress in the initial surface stress parameters and the force component in the displacement direction is calculated to obtain a third matching value. Then, surface stress parameters equal in magnitude to the third matching value and in the same direction as the target displacement are rematched from the preset mechanical simulation parameter library until the displacement deviation meets the preset displacement deviation requirement. If the displacement deviation meets the preset displacement deviation requirement, the currently matched surface stress parameter is output as the target surface stress parameter.

[0049] One preferred implementation method is described in [reference]. Figure 4 , Figure 5 and Figure 6 , Figure 4 A schematic diagram of the force analysis of the second connecting unit in the digital model generation method for invisible orthodontic appliances based on traction force analysis provided in a certain embodiment of the present invention. Figure 1 ; Figure 5 A schematic diagram of the force analysis of the second connecting unit in the digital model generation method for invisible orthodontic appliances based on traction force analysis provided in a certain embodiment of the present invention. Figure 2 ; Figure 6 A schematic diagram of the force analysis of the second connecting unit in the digital model generation method for invisible orthodontic appliances based on traction force analysis provided in a certain embodiment of the present invention. Figure 3 ;like Figure 4 , Figure 5 and Figure 6As shown, the yellow sites near the tooth root are the micro-implant sites, the yellow sites on the tooth surface are the attachment points of the traction hooks, the black devices with different heights are the traction hooks 1, the red straight line simulates the second connecting unit 2 connecting the micro-implant and the traction hook 1, and the orange sites are the dental impedance sites. Then, force analysis is performed on the traction hook 1, and the light green force along the direction of the second connecting unit 2 is the anchorage screw traction force. The dark green force is the traction force of the anchor nail. The decomposition force, among which, Characterized as force components in the displacement direction; Based on the obtained displacement direction force components By determining the force components in the direction of displacement The relationship between the direction of the displacement and the direction of the target displacement, and the force components in the displacement direction. The relationship between the magnitude of the resultant surface stress and the surface stress parameters is used for iterative optimization. One explanation is found in [link to relevant documentation]. Figure 7 , Figure 7 A schematic diagram illustrating the mechanical relationship analysis of the displacement direction force components, target displacement direction, and surface stress resultant force in a digital model generation method for invisible orthodontic appliances based on traction force analysis, provided in a certain embodiment of the present invention; as shown. Figure 7 As shown, Figure 7 (a) in the diagram illustrates the mechanical relationship analysis where the direction of the force component in the displacement direction is the same as the target displacement direction and the force component in the displacement direction is less than the resultant force of the surface stress in the initial surface stress parameters; Figure 7 In (a), This represents the resultant surface stress in the initial surface stress parameters. The direction of this resultant surface stress is consistent with the target displacement direction, and it is indicated by a yellow arrow. The force component in the displacement direction is indicated by a dark green arrow. The first matching value is represented by a red arrow; if the force component in the displacement direction... The direction is the same as the target displacement direction and the force component in the displacement direction The resultant surface stress is less than the initial surface stress parameter. This indicates that the displacement direction force component of the target traction force parameter at this time... This results in a larger force in the direction of the target displacement, in order to ensure the resultant force of surface stress during the overall correction process. Unaffected, the forces acting in the target displacement direction need to be balanced, which is done by calculating the resultant surface stress in the initial surface stress parameters. Force components in the direction of displacement The difference is used to obtain the first matching value. With the first matching value As an adjustment, the surface stress resultant force is rematched from the preset mechanical simulation parameter library. Size and first matching value The magnitudes are equal and the resultant surface stress is equal. The surface stress parameters are in the same direction as the target displacement direction, so that the resultant surface stress force is... Unaffected by force components in the direction of displacement The displacement deviation remains unchanged despite the influence of the surface stress parameters. By optimizing and iterating the surface stress parameters, the displacement deviation can be made to meet the preset displacement deviation requirement. In this embodiment, the preset displacement deviation requirement can be set to a displacement deviation of <0.1mm. like Figure 7 As shown, Figure 7 (b) in the diagram illustrates the mechanical relationship analysis where the direction of the force component in the displacement direction is the same as the target displacement direction and the force component in the displacement direction is greater than the resultant force of the surface stress in the initial surface stress parameters; Figure 7 In (b), This represents the resultant surface stress in the initial surface stress parameters. The direction of this resultant surface stress is consistent with the target displacement direction, and it is indicated by a yellow arrow. The force component in the displacement direction is indicated by a dark green arrow. The second matching value is represented by a red arrow; if the force component in the displacement direction... The direction is the same as the target displacement direction and the force component in the displacement direction Surface stress resultant force greater than the initial surface stress parameter This indicates the displacement direction force component of the target traction force parameter at this time. This results in a larger force in the direction of the target displacement, in order to ensure the resultant force of surface stress during the overall correction process. Unaffected, the forces in the target displacement direction need to be balanced through calculation. Displacement direction force component The resultant force of surface stress in the initial surface stress parameters The difference is used to obtain the second matching value. And rematch the surface stress resultant force from the preset mechanical simulation parameter library. Size and second matching value Equal in size and resultant surface stress The surface stress parameters whose direction is opposite to the target displacement direction are used to ensure that the resultant surface stress force... Unaffected by force components in the direction of displacement The displacement deviation remains unchanged despite the influence of the surface stress parameters. By optimizing and iterating the surface stress parameters, the displacement deviation can be made to meet the preset displacement deviation requirement. In this embodiment, the preset displacement deviation requirement can be set to a displacement deviation of <0.1mm. like Figure 7 As shown, Figure 7 (c) in the diagram illustrates the mechanical relationship analysis where the direction of the force component in the displacement direction is opposite to the direction of the target displacement; Figure 7 In (c), This represents the resultant surface stress in the initial surface stress parameters. The direction of this resultant surface stress is consistent with the target displacement direction, and it is indicated by a yellow arrow. The force component in the displacement direction is indicated by a dark green arrow. The third matching value is represented by a red arrow; if the force component in the displacement direction... The direction is opposite to the target displacement direction, indicating that the displacement force component of the target traction force parameter is at this time. This results in a smaller force in the direction of the target displacement, in order to ensure the resultant force of surface stress during the overall correction process. Unaffected, it is necessary to balance the forces in the direction of the target displacement. It is worth mentioning that when the force components in the displacement direction... When the direction of the force is opposite to the direction of the target displacement, regardless of the displacement direction force component The magnitude of the stress will cause the force in the target displacement direction to be smaller, so there is no need to classify and discuss its magnitude. Specifically, the resultant force of surface stress in the initial surface stress parameters can be calculated. Force components in the direction of displacement The sum of these values ​​yields the third matching value. And rematch the surface stress resultant force from the preset mechanical simulation parameter library. Size and third matching value The magnitudes are equal and the resultant surface stress is equal. The surface stress parameters are in the same direction as the target displacement direction, so that the resultant surface stress force is... Unaffected by force components in the direction of displacement The influence of the surface stress remains unchanged. By optimizing and iterating the surface stress parameters, the displacement deviation can be made to meet the preset displacement deviation requirement. In this embodiment, the preset displacement deviation requirement can be set to a displacement deviation of <0.1mm. It is worth mentioning that surface stress is the force acting on the tooth surface, and the resultant surface stress can be calculated using existing mature methods such as integration. Furthermore, if the force component in the displacement direction... The direction is the same as the target displacement direction and the force component in the displacement direction Equal to the resultant surface stress in the initial surface stress parameters At this time, the force component in the displacement direction Surface stress resultant force The difference is 0, which is equivalent to the force component in the displacement direction. Can replace surface stress resultant force As the force acting in the direction of displacement, the resultant surface stress can be rematched from the preset mechanical simulation parameter library. The surface stress parameter with a magnitude of 0 should be noted; it should be noted that the resultant surface stress... The initial orthodontic appliance digital model corresponding to a surface stress parameter of 0 does not mean that no force is exerted on the teeth; it simply means that the resultant surface stress is zero. The forces generated on the tooth surface by the initial digital model of the orthodontic appliance with a surface stress parameter of magnitude 0 can cancel each other out, and can be represented as the resultant surface stress through integral calculation. The size is 0.

[0050] Finally, if the displacement deviation meets the preset displacement deviation requirement, the current matched surface stress parameter is output as the target surface stress parameter. That is, when the displacement deviation meets the preset displacement deviation requirement, the current surface stress parameter obtained from the last match is used as the target surface stress parameter.

[0051] In the above scheme, after the rotation direction adjustment is completed, the influence of the rotation direction adjustment process on the displacement direction is considered. The displacement direction force component is obtained by decomposing the traction force of the target anchor pin. Based on the relationship between the displacement direction force component and the target displacement direction, and the magnitude of the resultant force with the surface stress, the surface stress parameters are rematched from the preset mechanical simulation parameter library to eliminate displacement deviation. Thus, by analyzing the traction force to generate this displacement direction adjustment mechanism, the influence of rotation adjustment on the mechanical changes in the displacement direction is fully considered. Accurate control of the displacement direction is achieved by dynamically adjusting the surface stress. It also reflects the synergy between displacement direction control and rotation direction control, and considers matching strategies under three different conditions to comprehensively cover possible mechanical relationships, ensuring that the resultant force of the surface stress in the displacement direction meets the control requirements. Finally, by optimizing and iterating the surface stress parameters, the displacement deviation gradually approaches the preset displacement deviation requirement, which helps to improve the reliability of the digital model design of the orthodontic appliance, and thus improves the reliability of orthodontic treatment.

[0052] In a preferred embodiment, step 106 includes: if the rotational deviation meets the preset rotational deviation requirement, then determine the corresponding target traction hook attachment point and the height of the target traction hook according to the target anchorage nail traction force parameter; if the displacement deviation meets the preset displacement deviation requirement, then determine the corresponding target orthodontic digital model according to the target surface stress parameter; mark the target traction hook attachment point in the target orthodontic digital model, and add the target traction hook digital model to the target traction hook attachment point according to the height of the target traction hook, to obtain the invisible orthodontic digital model.

[0053] One preferred implementation involves obtaining the traction hook position parameters, including the target traction hook attachment point, and the traction hook height corresponding to the traction hook digital model, based on the obtained target anchorage screw traction force parameters. The target traction hook digital model is then determined based on the traction hook height. Next, based on the target surface stress parameters, the corresponding orthodontic digital model is obtained as the target orthodontic digital model. The target traction hook attachment point is marked in the target orthodontic digital model. Then, a Boolean addition operation is performed between the target traction hook digital model and the target orthodontic digital model to obtain a complete invisible orthodontic digital model. The target traction hook digital model is positioned at the target traction hook attachment point. Notably, the magnitude of the anchorage screw traction force can be adjusted by changing the tightness of the connector between the micro-implant and the traction hook; this connector is typically a rubber band.

[0054] In the above scheme, the optimized target traction hook digital model is integrated with the target aligner digital model to generate a complete invisible aligner digital model. This invisible aligner digital model includes not only a mechanically optimized aligner shell structure but also an adjustable traction hook system, ensuring that the required displacement and rotation directions can be controlled simultaneously during actual treatment. This helps improve the reliability of the aligner digital model design, thereby improving the reliability of orthodontic treatment.

[0055] Example 2 See Figure 8 , Figure 8 This is a schematic diagram of the module structure of a digital model generation system for invisible orthodontic appliances based on traction force analysis provided in a certain embodiment of the present invention, as shown below. Figure 8As shown, this embodiment of the invention proposes a digital model generation system for invisible aligners based on traction force analysis, comprising: an initial model construction module 201, used to generate target displacement direction, target rotation direction, and target dentition position based on pre-acquired current dentition position and preset orthodontic target, and construct an initial aligner digital model and an initial traction hook digital model according to the target dentition position; a first connection unit acquisition module 202, used to select the non-intersecting part of the current dentition position and the target dentition position to obtain the micro-implant predicted implantation site; simulate wearing the initial aligner digital model on the current dentition position, calculate the dentition impedance point of the current dentition position, obtain the traction hook height corresponding to the initial traction hook digital model according to the dentition impedance point and the preset orthodontic target, and connect the micro-implant predicted implantation site and the initial traction hook digital model according to the traction hook height to obtain the first connection unit; and a simulated dentition position acquisition module 203, used to match initial surface stress parameters and initial anchorage screw traction force parameters from a preset mechanical simulation parameter library based on the initial aligner digital model and the first connection unit, and construct an initial aligner digital model and an initial traction hook digital model based on the preset simulation... The treatment cycle involves simulating the current dentition position using initial surface stress parameters and initial anchorage screw traction force parameters to obtain the simulated dentition position. The rotation direction adjustment module 204 calculates displacement and rotation deviations based on the simulated and target dentition positions. Based on the target rotation direction, it re-matches the initial anchorage screw traction force parameters from a preset mechanical simulation parameter library until the rotation deviation meets the preset rotation deviation requirements, thus obtaining the target anchorage screw traction force parameters. The displacement direction adjustment module 205 obtains the displacement direction force component based on the target anchorage screw traction force parameters. Based on the displacement direction force component and the target displacement direction, it re-matches the initial surface stress parameters from a preset mechanical simulation parameter library until the displacement deviation meets the preset displacement deviation requirements, thus obtaining the target surface stress parameters. The invisible aligner digital model generation module 206 obtains a target traction hook digital model based on the target anchorage screw traction force parameters, obtains a target aligner digital model based on the target surface stress parameters, and generates an invisible aligner digital model based on the target traction hook digital model and the target aligner digital model.

[0056] This invention proposes a digital model generation system for invisible aligners based on traction force analysis. It employs a method that considers potential deviations in the displacement direction after adjusting the rotation direction and makes further adjustments. To ensure that the resultant force in the rotation and displacement directions remains constant during treatment, after obtaining the traction force parameters of the target anchorage screw, the displacement force component is acquired and re-matched to the initial surface stress parameters. Thus, through traction force analysis, the influence of rotation direction adjustments on displacement direction deviations is fully considered, demonstrating the synergy between displacement and rotation direction control. Compared to existing technologies, this system can simultaneously meet the treatment goals in both displacement and rotation directions, ensuring accurate control of tooth movement during treatment and improving the reliability of orthodontic treatment.

[0057] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

[0058] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. Furthermore, the described specific features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of those different embodiments or examples.

[0059] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "a plurality of" means two or more, unless otherwise explicitly specified.

Claims

1. A method for generating digital models of invisible orthodontic appliances based on traction force analysis, characterized in that, include: Based on the pre-acquired current dentition position and preset orthodontic target, the target displacement direction, target rotation direction and target dentition position are generated, and the initial orthodontic appliance digital model and the initial traction hook digital model are constructed according to the target dentition position; The non-overlapping portion between the current dentition position and the target dentition position is selected to obtain the predicted implantation site for the micro-implant; The initial orthodontic appliance digital model is simulated and worn on the current dentition position. The dentition impedance point at the current dentition position is calculated. The traction hook height corresponding to the initial traction hook digital model is obtained based on the dentition impedance point and the preset orthodontic goal. The micro implant predicted implantation site and the initial traction hook digital model are connected based on the traction hook height to obtain the first connection unit. Based on the initial orthodontic appliance digital model and the first connecting unit, the initial surface stress parameters and the initial anchorage screw traction force parameters are matched from the preset mechanical simulation parameter library. Based on the preset simulation treatment cycle, the current dentition position is simulated and treated using the initial surface stress parameters and the initial anchorage screw traction force parameters to obtain the simulated dentition position. Based on the simulated tooth row position and the target tooth row position, the displacement deviation and rotation deviation are calculated. Based on the target rotation direction, the initial anchorage nail traction force parameters are rematched from the preset mechanical simulation parameter library until the rotation deviation meets the preset rotation deviation requirements, thus obtaining the target anchorage nail traction force parameters. Based on the traction force parameters of the target anchor pin, the displacement direction force component is obtained. Based on the displacement direction force component and the target displacement direction, the initial surface stress parameters are rematched from the preset mechanical simulation parameter library until the displacement deviation meets the preset displacement deviation requirements, and the target surface stress parameters are obtained. A digital model of the target traction hook is obtained based on the traction force parameters of the target anchorage nail, a digital model of the target orthodontic appliance is obtained based on the target surface stress parameters, and a digital model of the invisible orthodontic appliance is generated based on the digital model of the target traction hook and the digital model of the target orthodontic appliance.

2. The method for generating a digital model of an invisible aligner based on traction force analysis as described in claim 1, characterized in that, Based on the pre-acquired current dentition position and preset treatment target, the system generates target displacement direction, target rotation direction, and target dentition position. Based on the target dentition position, it constructs an initial digital model of the orthodontic appliance and an initial digital model of the traction hook, including: Multimodal oral data is acquired based on preset data acquisition equipment to obtain oral CBCT image data, 3D optical surface scanning data and periodontal tissue ultrasound imaging data; Based on a preset multimodal registration algorithm, the oral CBCT image data, the 3D optical surface scan data, and the periodontal tissue ultrasound imaging data are aligned in a preset spatial coordinate system. In the preset spatial coordinate system, the tooth morphology information, root position information, intraoral soft tissue surface morphology information, and jawbone morphology information in the oral CBCT image data, 3D optical surface scan data, and periodontal tissue ultrasound imaging data are fused to construct a three-dimensional digital model of the oral cavity. Based on the aforementioned three-dimensional digital model of the oral cavity, the current position of the dental arch is obtained; Based on the current dentition position and the preset orthodontic goal, a predicted movement path is generated to move the current dentition position to the dentition position that satisfies the preset orthodontic goal; Based on the predicted movement path, the orthodontic process is divided into several path sequences, and each path sequence corresponds to a predicted dentition stage, resulting in several predicted dentition stages. Based on the preset historical orthodontic prediction model and several predicted dentition stages, according to the current dentition position and the predicted movement path of each predicted dentition stage, the target dentition position, the target displacement direction of the current dentition position, and the target rotation direction of the current dentition position are generated for each predicted dentition stage. Based on the target dentition position, an initial digital model of the orthodontic appliance and an initial digital model of the traction hook are constructed.

3. The method for generating a digital model of an invisible aligner based on traction force analysis as described in claim 2, characterized in that, In the step of generating the target dentition position, target displacement direction, and target rotation direction for each predicted dentition stage based on a preset historical orthodontic prediction model, for several predicted dentition stages, according to the current dentition position and the predicted movement path for each predicted dentition stage, the preset process of the preset historical orthodontic prediction model includes: Acquire several historical orthodontic data sets, and from these historical orthodontic data sets, obtain the historical initial dentition position, the historical dentition position movement path, the historical target dentition position, the target displacement direction, and the target rotation direction corresponding to each historical dentition position. Using the historical target dentition position corresponding to each historical orthodontic data as the output target, the historical initial dentition position, the historical dentition position movement path, the target displacement direction, and the target rotation direction of the historical dentition position corresponding to each historical orthodontic data are used as the input training set to train the preset deep learning model, thereby obtaining the preset historical orthodontic prediction model.

4. The method for generating a digital model of an invisible aligner based on traction force analysis as described in claim 3, characterized in that, Based on the target dentition position, an initial digital model of the orthodontic appliance and an initial digital model of the traction hook are constructed, including: Based on the current dental arch position, the target displacement direction of the current dental arch position, and the target rotation direction of the current dental arch position, obtain the displacement and rotation angle of each tooth position in the movement from the current dental arch position to the target dental arch position; Based on the target tooth row position, a tooth-enclosing shell is generated along the outer surface of each tooth position with a preset extension distance; Based on the displacement and rotation angle of each tooth position in the target tooth row, initial traction hook attachment points are set on the outer surface of the tooth position enclosure, and an initial traction hook digital model is constructed based on the initial traction hook attachment points. Based on the displacement and rotation angle of each tooth in the target dentition position, a negative cavity complementary to the crown morphology is constructed on the inner surface of the tooth-enclosing shell, thereby constructing an initial digital model of the orthodontic appliance corresponding to the target dentition position.

5. The method for generating a digital model of an invisible aligner based on traction force analysis as described in claim 4, characterized in that, In the step of matching initial surface stress parameters and initial anchorage screw traction force parameters from a preset mechanical simulation parameter library based on the initial orthodontic appliance digital model and the first connecting unit, and simulating orthodontic treatment of the current dentition position based on the initial surface stress parameters and initial anchorage screw traction force parameters according to a preset simulation treatment cycle, to obtain the simulated dentition position, the preset process of the preset mechanical simulation parameter library includes: Based on several historical orthodontic data, a historical three-dimensional digital model of the oral cavity, a historical digital model of the orthodontic appliance corresponding to the historical three-dimensional digital model of the oral cavity, and a historical digital model of the traction hook are obtained from the several historical orthodontic data. Based on a preset simulation algorithm, the historical oral cavity three-dimensional digital model and the corresponding historical orthodontic appliance digital model are divided into several grids. Based on historical orthodontic goals, the stress distribution generated by the inner surface of the historical orthodontic appliance digital model and the tooth surface of the historical oral cavity three-dimensional digital model is solved within each grid; based on the historical orthodontic appliance digital model and the stress distribution, surface stress parameters are obtained. Traverse several of the aforementioned grids, obtain the historical micro-implant sites, historical traction hook attachment points, and historical traction hook heights based on the historical treatment goals and the historical traction hook digital model, and obtain the position of the historical traction hook based on the historical traction hook attachment points and the historical traction hook heights; connect the historical micro-implant sites and historical traction hooks based on the positions of the historical traction hooks to obtain the second connection unit. The resistance center of each tooth in the dentition is calculated based on the historical three-dimensional digital model of the oral cavity. The resistance point of the dentition is solved based on the resistance center of each tooth, and the anchorage screw traction force is solved based on the second connecting unit. The anchorage screw traction force parameter is obtained based on the dentition resistance point and the anchorage screw traction force. The surface stress parameters and the anchor pin traction force parameters are integrated into a preset mechanical simulation parameter library.

6. The method for generating a digital model of an invisible aligner based on traction force analysis as described in claim 1, characterized in that, Based on the initial orthodontic appliance digital model and the first connecting unit, initial surface stress parameters and initial anchorage screw traction force parameters are matched from a preset mechanical simulation parameter library. Based on a preset simulated treatment cycle, the current dentition position is simulated and treated using the initial surface stress parameters and initial anchorage screw traction force parameters to obtain the simulated dentition position, including: The initial surface stress parameters and the initial anchorage screw traction force parameters are matched from the preset mechanical simulation parameter library, and the initial surface stress parameters are set in the initial orthodontic digital model, and the initial anchorage screw traction force parameters are set in the first connection unit; Based on the preset simulated treatment cycle, the initial surface stress parameters and initial anchorage screw traction force parameters are simulated and applied to the current dentition position through the initial orthodontic appliance digital model and the first connection unit; Each time a mechanical simulation is completed, the simulated dentition position for the corresponding preset simulation treatment cycle is obtained.

7. The method for generating a digital model of an invisible aligner based on traction force analysis as described in claim 1, characterized in that, Based on the simulated tooth row position and the target tooth row position, the displacement deviation and rotation deviation are calculated. Based on the target rotation direction, the initial anchorage screw traction force parameters are rematched from the preset mechanical simulation parameter library until the rotation deviation meets the preset rotation deviation requirement, thus obtaining the target anchorage screw traction force parameters, including: The displacement deviation and rotation deviation are obtained by comparing the simulated tooth row position and the target tooth row position; If the rotational deviation does not meet the preset treatment target, the initial anchorage nail traction force parameters are rematched from the preset mechanical simulation parameter library according to the target rotation direction, and the first connecting unit is adjusted according to the rematched initial anchorage nail traction force parameters until the rotational deviation meets the preset rotational deviation requirement. The initial traction hook digital model is set on the initial traction hook attachment point, and the initial traction hook attachment point is set on the initial orthodontic appliance digital model. Adjusting the first connecting unit includes: adjusting the traction hook height corresponding to the initial traction hook digital model and / or adjusting the position of the initial traction hook attachment point. If the rotational deviation meets the preset rotational deviation requirement, the current matched initial anchorage nail traction force parameter is output as the target anchorage nail traction force parameter.

8. The method for generating a digital model of an invisible aligner based on traction force analysis as described in claim 7, characterized in that, Based on the traction force parameters of the target anchor pin, the displacement direction force component is obtained. Based on the displacement direction force component and the target displacement direction, the initial surface stress parameters are rematched from the preset mechanical simulation parameter library until the displacement deviation meets the preset displacement deviation requirement, thus obtaining the target surface stress parameters, including: Based on the target anchorage nail traction force parameters, the target anchorage nail traction force is decomposed in the target displacement direction using a preset force decomposition algorithm to obtain the displacement direction force component; If the direction of the displacement force component is the same as the target displacement direction and the displacement force component is less than the resultant force of surface stress in the initial surface stress parameters, then the difference between the resultant force of surface stress in the initial surface stress parameters and the displacement force component is calculated to obtain a first matching value. Then, surface stress parameters that are equal in magnitude to the first matching value and the same as the target displacement direction are rematched from the preset mechanical simulation parameter library until the displacement deviation meets the preset displacement deviation requirement. If the direction of the displacement force component is the same as the target displacement direction and the displacement force component is greater than the resultant force of surface stress in the initial surface stress parameters, then the difference between the displacement force component and the resultant force of surface stress in the initial surface stress parameters is calculated to obtain a second matching value. Then, surface stress parameters that are equal in magnitude to the second matching value and opposite in direction to the target displacement are rematched from the preset mechanical simulation parameter library until the displacement deviation meets the preset displacement deviation requirement. If the direction of the displacement force component is opposite to the target displacement direction, the sum of the resultant surface stress and the displacement force component in the initial surface stress parameters is calculated to obtain the third matching value. Then, the surface stress parameters that are equal in magnitude to the third matching value and have the same direction as the target displacement are rematched from the preset mechanical simulation parameter library until the displacement deviation meets the preset displacement deviation requirement. If the displacement deviation meets the preset displacement deviation requirement, the currently matched surface stress parameter is output as the target surface stress parameter.

9. The method for generating a digital model of an invisible aligner based on traction force analysis as described in claim 8, characterized in that, The process of obtaining a digital model of the target traction hook based on the traction force parameters of the target anchorage nail, obtaining a digital model of the target orthodontic appliance based on the target surface stress parameters, and generating a digital model of the invisible orthodontic appliance based on the digital model of the target traction hook and the digital model of the target orthodontic appliance includes: If the rotational deviation meets the preset rotational deviation requirement, then the corresponding target traction hook attachment point and the height of the target traction hook are determined according to the target anchor nail traction force parameters. If the displacement deviation meets the preset displacement deviation requirement, then the corresponding target orthodontic digital model is determined according to the target surface stress parameters; The attachment point of the target traction hook is marked in the digital model of the target orthodontic appliance, and the digital model of the target traction hook is added to the attachment point of the target traction hook according to the height of the target traction hook to obtain the digital model of the invisible orthodontic appliance.

10. A digital model generation system for invisible orthodontic appliances based on traction force analysis, characterized in that, The method for generating a digital model of an invisible aligner based on traction force analysis as described in any one of claims 1 to 9 includes: The initial model building module is used to generate the target displacement direction, target rotation direction and target dentition position based on the pre-acquired current dentition position and preset treatment target, and to build the initial orthodontic appliance digital model and the initial traction hook digital model according to the target dentition position; The first connection unit acquisition module is used to select the non-intersecting part of the current dentition position and the target dentition position to obtain the micro-implant predicted implantation site; simulate wearing the initial orthodontic appliance digital model on the current dentition position, calculate the dentition impedance site of the current dentition position, obtain the traction hook height corresponding to the initial traction hook digital model according to the dentition impedance site and the preset orthodontic target, and connect the micro-implant predicted implantation site and the initial traction hook digital model according to the traction hook height to obtain the first connection unit; The simulated dentition position acquisition module is used to match initial surface stress parameters and initial anchorage screw traction force parameters from a preset mechanical simulation parameter library based on the initial orthodontic appliance digital model and the first connection unit, and to simulate orthodontic treatment of the current dentition position based on a preset simulated treatment cycle using the initial surface stress parameters and the initial anchorage screw traction force parameters to obtain the simulated dentition position. The rotation direction adjustment module is used to calculate the displacement deviation and rotation deviation based on the simulated tooth row position and the target tooth row position, and to rematch the initial anchorage nail traction force parameters from the preset mechanical simulation parameter library based on the target rotation direction until the rotation deviation meets the preset rotation deviation requirements, thereby obtaining the target anchorage nail traction force parameters. The displacement direction adjustment module is used to obtain the displacement direction force component based on the target anchor nail traction force parameter, and based on the displacement direction force component and the target displacement direction, rematch the initial surface stress parameter from the preset mechanical simulation parameter library until the displacement deviation meets the preset displacement deviation requirement, thereby obtaining the target surface stress parameter; The invisible aligner digital model generation module is used to obtain a target traction hook digital model based on the target anchorage nail traction force parameters, obtain a target aligner digital model based on the target surface stress parameters, and generate an invisible aligner digital model based on the target traction hook digital model and the target aligner digital model.

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