An appliance orthodontic force assessment display system

Abstract

The application provides an appliance orthodontic force evaluation and display system, comprising: a preprocessing unit configured to preprocess oral orthodontic data to generate a dynamic dental arch digital model; a retrieval unit configured to retrieve a candidate appliance digital model from a database according to the dynamic dental arch digital model and an orthodontic prescription; a simulation unit configured to simulate a wearing process using the dynamic dental arch digital model and the candidate appliance digital model and obtain a distribution of orthodontic force on the dental arch after the dental arch wears the appliance; an evaluation unit configured to evaluate whether the distribution of orthodontic force meets the orthodontic prescription and biomechanical limit conditions; and a display unit configured to visually display the dynamic dental arch digital model, the candidate appliance digital model, the wearing process, and the distribution of orthodontic force. The appliance orthodontic force evaluation and display system provided by the application can accurately evaluate and display orthodontic force of an appliance and obtain a digital model of the appliance used for orthodontics.

Description

Technical Field

[0001] This application relates to the field of orthodontic technology, specifically, to provide a system for evaluating and displaying the orthodontic force of an orthodontic appliance. Background Technology

[0002] Orthodontics is a general term for treatment methods that correct various deformities in the oral cavity, such as orthodontic treatment for malocclusion, arch expansion for crowding, and bite guidance training for malocclusion. In addition to medication and surgery, orthodontic treatment often requires the wearing of appropriate orthodontic appliances, such as shell-shaped appliances (also known as invisible aligners) to align teeth. These appliances are generally designed and manufactured using digital methods, and their orthodontic effects need to be demonstrated and evaluated during the design phase to analyze whether the appliance can achieve the expected orthodontic goals. For example, patent 201380007617.X virtually places dental instruments onto a set of virtual teeth to determine one or more forces applied to the teeth, and then demonstrates and evaluates these forces.

[0003] The existing systems described above are generally suitable for demonstrating and evaluating the orthodontic forces exerted on teeth by shell-shaped orthodontic appliances. However, these systems are not suitable for demonstrating and evaluating the orthodontic forces generated by occlusal guiding appliances, which have combined orthodontic functions. The main reasons are as follows: First, the methods described above are generally based on force-torque theory, using linear finite element methods to calculate the orthodontic forces and displacements caused by shell-shaped orthodontic appliances (invisible aligners). However, simulating the orthodontic effects of such appliances requires incorporating the jawbone into the biomechanical simulation analysis to more accurately determine the forces between the orthodontic appliance and human tissues such as teeth, gums, alveolar bone, and maxillae, as well as the effects on soft tissues such as muscles. Such biomechanical models have… The orthodontic process involves complex nonlinear interactions, so simply using the linear finite element method for simulation cannot reflect the complex biomechanical responses and the interaction between the appliance and human tissues. Secondly, for occlusal guiding appliances made of soft silicone material, different occlusal relationships and occlusal forces will cause different changes in the appliance during the dynamic wearing process of occluding the upper and lower teeth, resulting in different orthodontic force distributions on the oral tissues. Therefore, it is necessary to incorporate the appliance wearing process into the simulation to improve the accuracy of the simulation results and thus enhance the credibility of the orthodontic effect assessment. Finally, it is necessary to optimize various processes such as model generation / retrieval and simulation of the dynamic wearing process to accelerate the calculation speed of orthodontic force distribution. Summary of the Invention

[0004] To address the problems in the prior art, the purpose of this application is to provide a system capable of comprehensively assessing and demonstrating the orthodontic forces experienced by various parts of the oral cavity after the teeth and jaws are fitted with orthodontic appliances, and quickly determining the appropriate orthodontic appliance for oral orthodontics.

[0005] The embodiments of this application can be implemented through the following technical solutions: An orthodontic force assessment and display system for orthodontic appliances is provided for assessing and displaying the orthodontic forces experienced by the teeth and jaws after wearing orthodontic appliances and for obtaining a digital model of the orthodontic appliance used for orthodontics. The orthodontic forces include orthodontic forces on at least one tooth, orthodontic forces on the maxilla and / or mandible, and traction forces on the condyles. The orthodontic force assessment and display system includes: The preprocessing unit is used to preprocess orthodontic data to generate a dynamic digital model of the jaw, which is generated based on the actual occlusal relationship of the upper and lower jaws. The retrieval unit is used to retrieve alternative orthodontic appliance digital models from the database based on the dynamic dental digital model and orthodontic prescription. The simulation unit uses the dynamic dental digital model and the alternative orthodontic appliance digital model to simulate the wearing process, and obtains the distribution of orthodontic forces on the dental jaw after wearing the orthodontic appliance based on the simulation. The evaluation unit is used to evaluate whether the distribution of the orthodontic force meets the orthodontic prescription and biomechanical constraints. If the evaluation result is met, the digital model of the candidate orthodontic appliance is determined as the digital model of the orthodontic appliance used for orthodontics. If the evaluation result is not met, the digital model of the candidate orthodontic appliance is optimized and re-simulated by the simulation unit or re-searched by the retrieval unit. The display unit is used to visually display the dynamic digital model of the jaw, the digital model of the alternative orthodontic appliance, the wearing process, and the distribution of the orthodontic force.

[0006] Furthermore, the preprocessing unit includes: The data retrieval module is used to retrieve orthodontic data from the database. The orthodontic data includes a digital model of the dentition to be treated, the actual occlusal relationship of the dentition to be treated, and the orthodontic prescription. The positioning and binding module positions and binds the digital model of the dentition to be treated to the actual occlusal relationship in order to generate a dynamic digital model of the dentition.

[0007] Preferably, the actual occlusal relationship includes: the relative positional relationship of the upper and lower jaws in a non-occlusal state, the relative positional relationship of the upper and lower jaws in an occlusal state, and the motion parameters of the condyle during the occlusal process.

[0008] Preferably, the motion parameters of the condyle during occlusion include: the inclination angle and / or the motion trajectory curve of the condyle during occlusion.

[0009] Furthermore, the dynamic dental digital model and the orthodontic appliance digital model are digital finite element models, and the simulation unit includes: The constitutive parameter setting module is used to set the finite element constitutive parameters of the dynamic dental digital model and the alternative orthodontic appliance digital model; The calculation parameter setting module is used to set the finite element calculation parameters; The initial state setting module is used to set the initial values ​​of the wearing parameters; The finite element calculation module, based on the initial values ​​of the wearing parameters and the calculation parameters, simulates the wearing process using the finite element calculation method to determine the wearing parameters and the distribution of the orthodontic force at any time during the simulation.

[0010] Furthermore, the finite element constitutive parameters include: material parameters, element parameters, and model type.

[0011] Furthermore, the wearing parameters include: the morphology of the candidate orthodontic appliance digital model, the morphology of the dynamic dental digital model, the relative positional relationship between the candidate orthodontic appliance digital model and the dynamic dental digital model during the wearing process, the movement parameters of the condyle during the wearing process, and the biting force of the upper and lower jaws during the wearing process.

[0012] The motion parameters of the condyle during the wearing process include: the tilt angle and / or the motion trajectory curve of the condyle during the wearing process.

[0013] Preferably, the finite element calculation method uses a nonlinear calculation method.

[0014] Furthermore, the calculation parameters include: the contact conditions and boundary conditions between the digital model of the candidate orthodontic appliance and the dynamic digital model of the jaw.

[0015] Preferably, the boundary condition includes the loading speed.

[0016] Preferably, the loading speed is 0.001 m / s to 3 m / s; the calculation parameters also include damping parameters.

[0017] Preferably, the distribution of the orthodontic force includes the magnitude and direction of the orthodontic force experienced by at least one part of the dynamic digital dental model.

[0018] Preferably, optimizing the digital model of the candidate orthodontic appliance specifically involves adjusting the shape of the digital model of the candidate orthodontic appliance or adjusting at least one of the following parameters: The initial values ​​of the finite element constitutive parameters, the finite element calculation parameters, and the wearing parameters.

[0019] Preferably, the biomechanical constraints include at least one of the following constraints: The maximum orthodontic force that each tooth can withstand, the maximum arch expansion force that the maxilla and / or mandible can withstand, the maximum traction force that the condyle can withstand, and the maximum range of space for condyle movement.

[0020] Preferably, the preprocessing unit further includes a precision adjustment module for adjusting the model precision of the dynamic dental digital model.

[0021] Preferably, the display unit includes one or more of the following devices: a desktop computer and laptop screen, a smart tablet, a smartphone, or a display terminal for an AR / VR device.

[0022] Preferably, the actual occlusal relationship is obtained by measuring the teeth to be treated using an articulator.

[0023] The orthodontic force assessment and demonstration system for orthodontic appliances provided by the embodiments of this application has at least the following beneficial effects: (1) The orthodontic force assessment and display system for orthodontic appliances provided in this application binds the independent digital models of the maxilla and mandible through three-dimensional registration and binding of occlusal relationships to form a dynamic digital model of the dentition and jaw, so that the relative movement of the maxilla and mandible can be realistically reproduced when simulating the wearing process of the orthodontic appliance, thereby improving the credibility of the finite element simulation results. (2) The orthodontic force evaluation and display system provided in this application uses a nonlinear finite element calculation method to calculate the distribution of orthodontic force at any time during the wearing process. Through this method, the changes in the orthodontic force applied to different parts of the jaw and the changes in the shape of the orthodontic appliance during the wearing process can be dynamically obtained. Based on the above information, the orthodontic effect of the candidate orthodontic appliance and its deviation from the orthodontic goal can be evaluated and displayed more accurately. (3) By judging whether the orthodontic force applied by the candidate orthodontic appliance meets the orthodontic prescription and exceeds the biomechanical limits, the orthodontic appliance that meets the orthodontic needs can be quickly identified and the potential discomfort or pain caused by the orthodontic appliance can be effectively avoided. Attached Figure Description

[0024] Figure 1 This is an architecture diagram of the orthodontic force assessment system for orthodontic appliances provided according to embodiments of this application; Figure 2A and Figure 2B A three-dimensional digital model of the maxillary and mandibular parts of the dentition to be treated, established based on measurement information of various parts of the oral cavity. Figure 3 A schematic diagram illustrating the actual occlusal relationship of the upper and lower jaws using an articulator; Figure 4 A schematic diagram of the maxilla, mandible, and temporomandibular joint; Figure 5A This is a schematic diagram illustrating the movement patterns of the mandible relative to the maxilla. Figure 5B This is a diagram illustrating the opening and closing of the lower jaw relative to the upper jaw. Figure 5C A schematic diagram showing the protrusion and retraction of the mandible relative to the maxilla; Figure 5D This is a schematic diagram of the lateral movement of the mandible relative to the maxilla; Figure 6 A flowchart illustrating the implementation of the positioning and binding module for generating a dynamic digital model of the jaw according to an embodiment of this application; Figures 7A to 7C This is a schematic diagram of a dynamic digital model of the jawbone during an opening process according to a specific embodiment of this application; Figure 8 A flowchart illustrating the implementation of the retrieval unit for retrieving digital models of candidate orthodontic appliances according to an embodiment of this application; Figure 9A A perspective view of a digital model of an alternative orthodontic appliance according to an embodiment of this application; Figure 9B A rear view of a digital model of an alternative orthodontic appliance according to an embodiment of this application; Figure 9C A top view of a digital model of an alternative orthodontic appliance according to an embodiment of this application; Figure 9D , Figure 9E They are respectively Figure 9C Cross-sectional views in the CC and DD directions; Figure 10A , Figure 10B The different wearing effects produced by setting different initial values ​​for the motion parameters of the condyle during the wearing process, obtained through finite element simulation, are shown respectively. Figure 11 This document compares the structural oscillations of the digital model of the orthodontic appliance before and after adding mass damping, according to embodiments of this application. Figures 12A to 12C The results of finite element simulation show the changes in orthodontic forces on the jaws at different stages of a specific wearing process; Figure 13 The results of finite element simulation show the changes in traction force on the condyle at different stages of a specific wearing process; Figure 14The stress-strain curves and corresponding deformation limits of the orthodontic appliance material obtained through finite element simulation are shown. Figure 15 This is a schematic diagram of a graphical user interface displayed on a display unit according to an embodiment of this application. Detailed Implementation

[0025] The present application will now be further described based on preferred embodiments and with reference to the accompanying drawings.

[0026] Furthermore, for ease of understanding, various components on the drawings have been enlarged or reduced, but this is not intended to limit the scope of protection of this application.

[0027] Singular forms of words also include plural meanings, and vice versa.

[0028] In the description of the embodiments of this application, it should be noted that if terms such as "upper," "lower," "inner," or "outer" are used to indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this application is in use, they are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application. In addition, in the description of this application, in order to distinguish different units, the terms "first," "second," etc. are used in this specification, but these are not limited by the manufacturing order, nor should they be construed as indicating or implying relative importance. Their names may differ in the detailed description and claims of this application.

[0029] The vocabulary used in this specification is for illustrative purposes and is not intended to limit the scope of this application. It should also be noted that, unless otherwise expressly specified and limited, the terms "set," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection, a direct connection, or an indirect connection via an intermediate medium; or they can refer to the internal communication between two components. Those skilled in the art will understand the specific meaning of these terms in this application.

[0030] This application provides a system for evaluating and displaying the orthodontic force of an orthodontic appliance. Figure 1 This is an architectural diagram of an orthodontic force assessment and demonstration system for an orthodontic appliance provided according to an embodiment of this application, such as... Figure 1 As shown, the orthodontic force assessment and demonstration system for orthodontic appliances provided in this application includes: The preprocessing unit is used to preprocess orthodontic data to generate a dynamic digital model of the jaw, which is generated based on the actual occlusal relationship of the upper and lower jaws. The retrieval unit is used to retrieve alternative orthodontic appliance digital models from the database based on the dynamic dental digital model and orthodontic prescription. The simulation unit uses the dynamic dental digital model and the alternative orthodontic appliance digital model to simulate the wearing process, and obtains the distribution of orthodontic forces on the dental jaw after wearing the orthodontic appliance based on the simulation. The evaluation unit is used to evaluate whether the distribution of the orthodontic force meets the orthodontic prescription and biomechanical constraints. If the evaluation result is met, the digital model of the candidate orthodontic appliance is determined as the digital model of the orthodontic appliance used for orthodontics. If the evaluation result is not met, the digital model of the candidate orthodontic appliance is optimized and re-simulated by the simulation unit or re-searched by the retrieval unit. The display unit is used to visually display the dynamic digital model of the jaw, the digital model of the alternative orthodontic appliance, the wearing process, and the distribution of the orthodontic force.

[0031] The orthodontic force assessment and display system provided in this application can be used to assess and display the orthodontic force experienced by the teeth and jaws after wearing orthodontic appliances and to obtain a digital model of the orthodontic appliance used for orthodontics. The orthodontic force includes the orthodontic force experienced by at least one tooth, the orthodontic force experienced by the maxilla and / or mandible, and the traction force experienced by the condyle.

[0032] The following describes in detail each unit of the orthodontic force assessment and demonstration system for orthodontic appliances provided in this application, with reference to the accompanying drawings and specific embodiments.

[0033] The preprocessing unit is primarily used to process orthodontic data from patients undergoing orthodontic treatment, generating a dynamic digital model of the jaw that can move according to the actual occlusal relationship for subsequent orthodontic force assessment. In some preferred embodiments of this application, the preprocessing unit includes a data retrieval module and a positioning and binding module.

[0034] The data retrieval module is used to retrieve orthodontic data from the database. The orthodontic data includes a digital model of the dentition to be treated, the actual occlusal relationship of the dentition to be treated, and the orthodontic prescription.

[0035] Specifically, for patients requiring orthodontic treatment, various existing oral medical testing equipment can be used to examine the appearance, internal structure, and relative relationships of various parts and tissues of the oral cavity. Common oral medical testing equipment includes devices such as 3D oral scanners for measuring the appearance of various parts of the oral cavity, X-ray / ultrasound imaging, CT scans, or MRI for measuring the internal structure of various parts of the oral cavity, and articulators for measuring the relative relationships of various parts of the oral cavity (such as the occlusal relationship of the upper and lower jaws). Based on the data obtained from the above measurements, digital modeling of various parts of the oral cavity can be performed, and measurement landmarks, lines, and surfaces of various parts of the oral cavity can be measured and calibrated, or information such as the relative relationships of various parts of the oral cavity can be obtained. Based on the above information, the attending physician can diagnose the type and severity of the patient's oral deformity, and formulate an orthodontic treatment plan and expected orthodontic goals, ultimately forming an orthodontic prescription for the patient. All the above information and orthodontic prescriptions can be stored as orthodontic data in various digital medical databases (the database can be a local database or a remote database) and accessed through a data retrieval module.

[0036] Figure 2A and Figure 2B The diagrams show three-dimensional digital models of the maxillary and mandibular portions of the dentition to be treated, built based on measurement information from various parts of the oral cavity. A typical three-dimensional digital model of the maxilla or mandible can further include multiple teeth, periodontal tissues (such as gingiva and periodontal ligament), and a three-dimensional digital model of the maxillary or mandibular bone. The data format and level of detail of the digital models can be adjusted according to specific application needs. For example, in some digital teaching scenarios, where only a schematic representation of the appearance and structure of the dentition is required, a triangular or quadrangular facet format can be used, and the number of faces can be appropriately reduced to improve real-time rendering speed. When a detailed study of the structure of the dentition and existing oral problems is required, it may be necessary to increase the modeling accuracy and the number of faces to meet the research needs. In other applications, such as finite element simulation of orthodontic treatment or virtual oral surgery navigation, it is necessary to materialize the various parts and assign them different parameters to form models of teeth, gingiva, periodontal ligament, and jawbone that can be physically interacted with. In the embodiments of this application, the aforementioned digital model of the teeth and jaws to be treated is stored as orthodontic data in various digital medical databases and is accessed through a data retrieval module.

[0037] Figure 3This diagram illustrates an articulator and its use to obtain the actual occlusal relationship between the upper and lower jaws. When performing orthodontic treatment on patients with malocclusion, special attention needs to be paid to the occlusal relationship between the upper and lower jaws, and traction force is applied to gradually adjust the occlusion towards the correct position. Figure 3 The jaw frame 500 shown can measure and record the position and posture data of the upper and lower jaws under different occlusal relationships, as well as the corresponding condylar movement data (through measurement point 530). The above data reflecting the actual occlusal relationship is also stored as orthodontic data in various digital medical databases and can be accessed through the data retrieval module.

[0038] In addition, orthodontic data also includes the orthodontic prescription issued by the dentist after diagnosing the teeth and jaws to be treated. A typical orthodontic prescription generally includes the diagnosis of various oral malocclusions of the teeth and jaws to be treated, the expected goals to be achieved through orthodontic procedures (such as the shape or parameters of the aligned teeth, the expected width of the dental arch after expansion, the adjusted occlusal relationship of the upper and lower jaws, etc.), the range of orthodontic forces to be applied to various parts of the teeth and jaws to achieve the above goals, the duration of orthodontic procedures, the duration of daily appliance wearing during orthodontic treatment, and the range of additional bite training forces required.

[0039] The preprocessing unit also includes a positioning and binding module, which positions and binds the digital models of the maxilla and mandible to generate a dynamic digital model of the teeth and jaws.

[0040] Existing technologies already include "integrated" digital models of the jaw that simultaneously include the maxillary and mandibular portions. However, in these existing "integrated" digital models, the positional relationship between the maxilla and mandible is often fixed and cannot accurately reproduce the various dynamic occlusal processes of the mandible relative to the maxilla.

[0041] Therefore, in this embodiment of the application, the digital models of the maxilla and mandible of the teeth to be treated are positioned according to their actual occlusal relationship through a positioning and binding module, and their motion trajectories in various types of occlusal processes are bound, thereby obtaining a dynamic digital model of the teeth that can accurately reproduce the real motion state of the teeth to be treated.

[0042] In some preferred embodiments of this application, the actual occlusal relationship of the maxilla and mandible may include the following: the relative positional relationship of the maxilla and mandible in a non-occlusal state, the relative positional relationship of the maxilla and mandible in an occlusal state, and the motion parameters of the condyle during occlusion. As described above regarding the jawbone system, the relative positional relationship of the maxilla and mandible in both occlusal and non-occlusal states can be obtained by measuring the jawbone system. Simultaneously, the motion parameters of the condyle during various occlusal processes can also be calculated based on the measurement data from the jawbone system.

[0043] The condyles, also known as condylar processes or articular processes, are the two protrusions at the end of the mandibular ramus of the mandible, located in the glenoid fossa of the temporomandibular joint. During various types of occlusion between the mandible and the maxilla, the condyles can perform large-angle, wide-range rotation and translation movements after being pulled. By recording the motion parameters of these movements, the actual occlusal relationship between the mandible and maxilla can be accurately obtained. Figure 4 A schematic diagram of the maxilla and mandible connected by the temporomandibular joint is shown. Figures 5A to 5D It illustrates various movements of the mandible. For example... Figure 4 and Figures 5A to 5D As shown, when the mandible 320 (generally, the mandible 320 includes the mandible bone and the mandibular dentition contained therein, as well as soft tissues such as the gingiva and periodontal ligament not shown in the figure) is subjected to force by different muscle groups such as the masseter muscle, temporalis muscle, medial pterygoid muscle, and lateral pterygoid muscle, that is, when various biting movements are performed relative to the maxilla 310 (generally, the maxilla 310 includes the maxilla bone and the maxillary dentition contained therein, as well as soft tissues such as the gingiva and periodontal ligament not shown in the figure), the condyle 330 is also pulled and rotated and translated accordingly, thereby forming a specific movement trajectory or movement curve.

[0044] In some specific embodiments of this application, the movement of the condyle 330 can be simplified to a rotational and translational movement along a straight line. That is, the movement parameter of the condyle during occlusion is the tilt angle of the movement trajectory of the condyle 330 during occlusion (the tilt angle can be the angle between the straight line of the movement trajectory of the condyle 330 and the horizontal plane or a specific measurement marker line of the maxilla). In other specific embodiments of this application, the movement parameter of the condyle 330 during occlusion can also be the movement trajectory curve of the condyle 330 during occlusion.

[0045] Figure 6 A flowchart illustrating the implementation of a positioning and binding module generating a dynamic digital model of the jaw according to a specific embodiment of this application is shown, as follows: Figure 6 As shown, the positioning and binding module first marks multiple positioning markers on the imported digital models of the maxilla and mandible; then, using the relative positional relationship of the maxilla and mandible in the occlusal state obtained by the articulator, it uses three-dimensional registration technology to achieve the registration of the maxilla and mandible; based on this, it further uses the relative positional relationship of the maxilla and mandible in the non-occlusal state obtained by the articulator and the corresponding condylar motion parameters to determine the motion trajectory of the mandible in various types of occlusion processes; finally, it binds it to the digital model of the mandible, thus obtaining a dynamic digital model of the dentition based on the actual occlusal relationship.

[0046] Figures 7A to 7C A specific embodiment of reproducing the actual mouth-opening process using a dynamic digital model of the jaw is shown, such as... Figures 7A to 7CAs shown, the dynamic digital model of the jaw includes a maxillary model 410 and a mandibular model 420. In some preferred embodiments, the maxillary model 410 and the mandibular model 420 can be further subdivided according to different parts into multiple maxillary tooth models 411, maxillary gingival models 412, multiple mandibular tooth models 421, mandibular gingival models 422, and models of parts not shown within the gingiva, such as the maxillary bone, mandibular bone, maxillary periodontal ligament, and mandibular periodontal ligament. In addition, in some specific embodiments, the dynamic digital model of the jaw also includes an upper abutment model 413 and a lower abutment model 423 adapted to tooling fixtures to facilitate assembly and manufacturing in subsequent orthodontic procedures.

[0047] In some embodiments, the digital models of the different parts can be assigned corresponding materials to form finite element models that can be used for simulation. Obviously, when performing finite element simulation of orthodontic forces on the jawbone, the upper abutment model and the lower abutment model do not need to be converted into finite element models, nor do they need to participate in the finite element simulation.

[0048] To more clearly demonstrate various occlusal processes, in some preferred embodiments, the actual occlusal relationships described above can be visualized, such as... Figures 7A to 7C The condyle 430 is visualized (i.e., the point represented by AX in the diagram). Furthermore, the inclination angle and / or trajectory curve of the condyle 430 during actual occlusion can also be visualized, such as... Figures 7A to 7C As shown, during the actual opening process, as the relative positional relationship between the mandibular model 420 and the maxillary model 410 gradually changes from an occlusal state to a non-occlusal state, the condyle 430 translates along the dotted line in the figure (which forms a fixed angle with the horizontal line OP), while the mandibular model 420 rotates around the condyle 430, thus completing the opening process.

[0049] In some preferred embodiments of this application, the preprocessing unit further includes a precision adjustment module for adjusting the model precision of the dynamic dental digital model. For example, in some specific embodiments of this application, the precision adjustment module can re-divide the mesh size and mesh density of the dynamic dental digital model through mesh reconstruction. The principle of re-dividation is to reduce the number of meshes by 50% to 80% while maintaining the precision of the original model, so as to improve the computational efficiency of subsequent simulations and the loading speed of the display. In some other embodiments of this application, those skilled in the art can also use other algorithms to further optimize the precision of the dynamic dental digital model.

[0050] After the preprocessing unit preprocesses the orthodontic data and generates a dynamic digital model of the dentition, the retrieval unit retrieves alternative digital models of orthodontic appliances from the database based on the dynamic digital model of the dentition to be treated and the orthodontic prescription issued by the doctor. Figure 8 This illustration shows a flowchart of an implementation of a retrieval unit retrieving alternative orthodontic digital models from a database according to a specific embodiment of this application. Figure 8 As shown, the retrieval unit obtains information from the orthodontic prescription regarding the expected goals of the orthodontic operation (such as the morphology or parameters of the dentition after tooth alignment, the expected morphology or width of the dental arch after expansion, and the expected occlusal relationship of the maxilla and mandible after adjustment) and / or the range of various types of orthodontic forces that need to be applied to various parts of the dentition to achieve the above goals. Then, based on the above information and combined with the morphology, structure, and actual occlusal relationship of each part of the dynamic dentition digital model, it retrieves candidate orthodontic appliance digital models from multiple appliance digital models stored in the database for further simulation and evaluation.

[0051] Figure 9A Schematic diagrams of digital models of alternative orthodontic appliances for evaluation and demonstration according to some preferred embodiments of this application are shown. This type of orthodontic appliance is also known as an occlusal guiding appliance. Figure 9B and 9C These are its rear view and top view, respectively. Figure 9D and Figure 9E These are cross-sectional views in the CC and DD directions, respectively. As shown in the figure, the candidate orthodontic appliance digital model 200 includes an outer wall 210 and an inner wall 220 that are approximately U-shaped, as well as an occlusal pad 230 connecting the inner wall 210 and the outer wall 220. Furthermore, the outer wall 210 can be subdivided into an upper outer wall 211 and a lower outer wall 212, and the inner wall 220 can be subdivided into an upper inner wall 221 and a lower inner wall 222. The inner surfaces of the upper outer wall 211, the upper inner wall 221, and the upper surface of the occlusal pad 230 form the upper alveolar ridge 240 for accommodating the maxillary dentition, and the inner surfaces of the lower outer wall 212, the lower inner wall 222, and the lower surface of the occlusal pad 230 form the lower alveolar ridge 250 for accommodating the mandibular dentition.

[0052] These orthodontic appliances with bite guidance functions are generally made of soft medical-grade silicone or similar materials. They are easily deformed under force and have less resilience compared to resin materials. They apply various types of orthodontic forces to the teeth, jawbone, and soft tissues in different parts of the oral cavity. The labial and lingual inner surfaces of the alveolar bone are designed to match the crown surfaces of ideally aligned teeth to apply corrective forces to at least one misaligned tooth. They extend along the mesiodistal direction according to the desired dental arch curve (e.g., ...). Figure 9C (As shown by the dotted line in the figure) to apply corrective force to the maxilla and / or mandible with abnormal dental arch development; at the same time, by adjusting the relative position of the upper and lower alveoli and parameters such as the thickness and inclination angle of the occlusal pad at different locations, traction force is applied to the condyle to adjust the occlusal relationship of the upper and lower jaws.

[0053] Apart from Figures 9A to 9EBesides the appliances shown, other types of orthodontic appliances can also simultaneously apply multiple types of orthodontic forces to various parts of the jaw. For example, an orthodontic system consisting of two shell-shaped appliances worn on the maxilla and mandible, an arched reinforcing structure on the palatal side of the shell-shaped appliances, and paired attachments on the occlusal, labial, buccal, or lingual sides of the two shell-shaped appliances can also apply different types of orthodontic forces to different parts and tissues in the oral cavity, including the orthodontic force applied to the teeth by the shell-shaped cavity, the arch-expanding force applied to the jawbone by the arched reinforcing structure, and the traction force applied to the condyles by the paired attachments that traction the maxilla and mandible. Those skilled in the art should understand that the orthodontic force assessment and demonstration system during treatment provided in this application embodiment can also simulate and evaluate such an orthodontic system.

[0054] After generating a dynamic digital model of the jaw and retrieving digital models of candidate orthodontic appliances, the simulation unit uses the aforementioned dynamic digital model of the jaw and the retrieved digital models of candidate orthodontic appliances to simulate the wearing process to obtain the distribution of orthodontic forces on the jaw after wearing the orthodontic appliances.

[0055] As analyzed above, the orthodontic appliance in this embodiment needs to accommodate both the maxilla and mandible to achieve the purpose of adjusting the occlusal relationship. Therefore, only by simulating the different wearing results caused by different wearing angles, speeds, and applied biting forces during the wearing / assembly process can the distribution of orthodontic forces applied by the appliance to various parts of the jaw be obtained to the greatest extent. Otherwise, it will greatly increase the error in analyzing and evaluating the orthodontic effect after wearing.

[0056] In some preferred embodiments of this application, the aforementioned dynamic dental digital model and orthodontic appliance digital model are digital finite element models. The simulation unit includes a constitutive parameter setting module, a calculation parameter setting module, an initial state setting module, and a finite element calculation module. The simulation unit sets (or assigns) the initial values ​​of the finite element constitutive parameters, finite element calculation parameters, and wearing parameters through the aforementioned modules, and simulates the wearing process of the orthodontic appliance using finite element calculation methods to obtain the wearing parameters and the distribution of orthodontic forces at any given time during the simulation.

[0057] In some embodiments of this application, the finite element constitutive parameters include material parameters, element parameters, and model types of the dynamic dental digital model and the alternative orthodontic appliance digital model. Further, in some preferred embodiments, the maxillary and mandibular models included in the dynamic dental digital model can be further subdivided into models of multiple teeth, models of soft tissues such as the gingiva and periodontal ligament, and models of the jawbone, and finite element constitutive parameters can be set for each. For example, the tooth model type can be set as a rigid body, its material parameters can be set to an elastic modulus of 10-30 GPA and a Poisson's ratio of 0.29-0.35, and the model's element parameters can be set as multi-mesh solid elements. Similarly, the model type of the silicone material used in the orthodontic appliance can be set as a deformable body, and constitutive parameters consistent with its properties can be set. The methods for setting finite element constitutive parameters according to the properties of different materials and the range of values ​​for the finite element constitutive parameters corresponding to different materials are known to those skilled in the art and will not be elaborated further here.

[0058] In some embodiments of this application, the finite element calculation parameters include the contact conditions and boundary conditions between the dynamic dental digital model and the alternative orthodontic appliance digital model.

[0059] In some specific embodiments of this application, contact conditions can be set according to the finite element model type of different parts. For example, the contact conditions between the teeth and the orthodontic appliance can be set as surface-to-surface or line-to-line contact between a rigid body and a deformable body; or the contact conditions between the gingiva and the orthodontic appliance can be set as surface-to-surface or line-to-line contact between deformable bodies. Those skilled in the art can flexibly set contact conditions according to the constitutive parameters of the jaw model and the orthodontic appliance model.

[0060] In some specific embodiments of this application, boundary conditions such as loading and constraints can be set according to the actual situation of wearing the orthodontic appliance. For example, the digital model of the candidate orthodontic appliance can be fixed, fixing the five translational / rotational degrees of freedom of the maxillary model of the dynamic dental digital model while releasing only its translational degree of freedom along the Z-axis (vertical direction); fixing the four translational / rotational degrees of freedom of the mandibular model of the dynamic dental digital model while releasing its translational degree of freedom along the Z-axis (vertical direction) and its translational degree of freedom along the X-axis (horizontal direction). Under this boundary condition, the maxillary model of the dynamic dental digital model will enter the candidate orthodontic appliance digital model vertically downwards, while the mandibular model will enter the candidate orthodontic appliance digital model with translational movement in the XZ plane without rotation. Alternatively, while keeping other degrees of freedom unchanged, the mandibular model's rotational degree of freedom around the Y-axis with the condyle as the center can be further released. The above settings enable the dynamic dental digital model to more accurately reproduce different occlusal processes such as opening and closing of the mouth and mandibular protrusion and retraction during finite element simulation. For example, the degrees of freedom of the mandible can be further increased, such as by increasing the degree of freedom of translation of the mandibular model along the Y-axis. The above settings enable the dynamic digital dental model to more accurately reproduce the lateral occlusion process in the finite element simulation.

[0061] It is important to note that releasing the aforementioned multiple degrees of freedom does not mean that the maxillary and mandibular parts can move relative to each other without restraint, thereby exceeding the limits of temporomandibular joint movement or the biomechanical constraints imposed on various parts of the oral cavity. To avoid the aforementioned problems, in the embodiments of this application, the initial values ​​of the wearing parameters can be set through the initial state setting module to further constrain the relative movement of the maxillary model, mandibular model, and alternative orthodontic appliance digital model.

[0062] Specifically, wearing parameters are used to characterize the various dynamically changing states of the dynamic dental digital model and the candidate orthodontic appliance digital model during the simulation of the entire wearing process. In some preferred embodiments of this application, wearing parameters include the morphology of the candidate orthodontic appliance digital model, the morphology of the dynamic dental digital model, the relative positional relationship between the candidate orthodontic appliance digital model and the dynamic dental digital model during the wearing process, the condylar motion parameters during the wearing process, and the occlusal forces of the maxilla and mandible during the wearing process. These wearing parameters continuously change from their initial values ​​throughout the wearing process, and through these changes, they exert complex influences on the distribution of orthodontic forces.

[0063] The movement parameters of the condyle during the wearing process include the tilt angle and / or curve of the movement trajectory. Clearly, before the upper and lower jaws contact the digital model of the alternative appliance, the movement parameters of the condyle are the same as those during occlusion without any appliance. That is, the initial values ​​of the movement parameters of the condyle during wearing can be set to be the same as those during occlusion, so that the condyle moves along the same angle or path as during occlusion without an appliance before the upper and lower jaws contact the digital model of the alternative appliance, and then changes in the movement angle and path occur after the upper and lower jaws begin to contact the digital model of the alternative appliance.

[0064] Figure 10A , Figure 10B The figures illustrate the different wearing effects resulting from setting different initial values ​​for the motion parameters of the condyle during the wearing process. As can be seen from the figures, for the same dynamic dental digital model and the same alternative appliance digital model 600, when different initial values ​​are set for the motion parameters, the positions of the maxillary dentition included in the maxillary model 410 and the mandibular dentition included in the mandibular model 420 entering the upper alveolar bone 640 and lower alveolar bone 650 of the appliance digital model 600 differ significantly, further resulting in significantly different force distributions between the maxillary model 410 and the mandibular model 420.

[0065] Furthermore, the bite force used by the upper and lower jaws during the wearing of orthodontic appliances varies, resulting in different final appliance positions. Specifically, a reasonable range of bite force can be set according to the orthodontic prescription provided by the doctor. For example, for a bite-inducing appliance primarily used for daytime muscle training, the bite force during wearing can be set within the muscle training bite force range; while for appliances that need to be worn during sleep, since multiple unconscious biting processes may occur during sleep, setting the bite force within the nocturnal bruxism bite force range is also acceptable.

[0066] In some preferred embodiments of this application, the occlusal force of the upper and lower jaws during wear can be obtained by sensors mounted on the dynamic digital model of the dental arch. These sensors are virtual sensors capable of simulating real force sensors, typically placed on the occlusal surface of the teeth or the contact surface where occlusion occurs. When a force is applied to the maxillary and mandibular models of the dynamic digital model of the dental arch to bring them into the digital model of the alternative orthodontic appliance, the sensors can obtain the occlusal force information and further adjust the applied force accordingly based on whether it is within an acceptable range.

[0067] The finite element method (FEM) module is used to simulate the wearing process of the candidate orthodontic appliance after determining the above parameters, in order to determine the wearing parameters at any time during the wearing process and the distribution of the orthodontic force. Specifically, the distribution of the orthodontic force includes the magnitude and direction of the orthodontic force experienced by at least one part of the dynamic digital model of the dentition.

[0068] In addition, in some embodiments of this application, finite element simulation can not only obtain the magnitude and direction of the orthodontic force on different parts of the dynamic digital model of the teeth and jaws, but also further obtain the torque exerted by the orthodontic appliance on the teeth, jaws and other parts. For example, based on the orthodontic force on a tooth model and combined with the position of the impedance center obtained by measurement or theoretical calculation, the torque applied to the tooth model can be easily determined.

[0069] Most existing methods for finite element simulation of the orthodontic effects of orthodontic appliances only perform static analysis of the interaction between teeth and orthodontic appliances, and the finite element calculation methods used are linear calculation methods. In the embodiments of this application, the finite element calculation method uses a nonlinear calculation method to perform dynamic analysis of the process of the appliance being worn onto the jawbone.

[0070] In some preferred embodiments of this application, the boundary conditions of the finite element calculation parameters also include loading conditions. Specifically, the loading condition can be a loading speed, for example, the loading speed can be set to 0.001 m / s to 3 m / s. By setting the above loading speed conditions, the process of wearing an orthodontic appliance at different occlusal speeds can be simulated. At the same time, appropriately increasing the loading speed can improve the calculation efficiency of simulating the orthodontic appliance wearing process.

[0071] The aforementioned loading speed can also be replaced by other loading conditions that can achieve the same effect. For example, in some embodiments of this application, the loading conditions can be loading displacement, loading rotation, loading force, muscle force, and other loading conditions that can be equivalent to a loading speed of 0.001 m / s to 3 m / s.

[0072] It should be noted that setting loading conditions such as loading speed may cause structural oscillations in the digital model of the orthodontic appliance, resulting in unreasonable changes in the shape of the appliance. Therefore, in some preferred embodiments of this application, the finite element calculation parameters set in step S32 also include damping parameters. Specifically, the damping parameters can be mass damping or other equivalent parameters, and the effective time range of the damping parameters is between 1 and 1000 times the time step of the finite element model. Figure 11 This illustration shows a comparison of structural oscillations in the digital model of the orthodontic appliance before and after adding mass damping in a specific embodiment. Figure 11As can be seen, increasing mass damping can significantly reduce the error in calculation results caused by structural oscillations.

[0073] Figures 12A to 12C The simulation results show the distribution of orthodontic forces on various parts of the maxillary model 410 of the dynamic digital model of the dentition at different stages of a specific wearing process. Multiple black arrows of different lengths indicate the magnitude and direction of the orthodontic forces on different parts. Similarly, the distribution of orthodontic forces on the mandibular part can also be obtained through finite element simulation. Figure 13 This illustrates the changes in traction force experienced by the condyle at different stages of a specific wearing process.

[0074] In the embodiments of this application, various judgment conditions can be set to terminate the simulation of the wearing process. For example, the simulation can be terminated when the biting force of the upper and lower jaws during the wearing process exceeds the average value of the maximum biting force limit in a human awake state; or the simulation can be terminated when the biting force exceeds the maximum biting force during human chewing (or the maximum biting force in an unconscious state). Furthermore, whether the changes in wearing parameters during the wearing process exceed the limitations of human biomechanics or the material limitations of the orthodontic appliance can be taken into consideration. For example, in some preferred embodiments, if the movement trajectory of the condyle during the wearing process exceeds the allowable range of motion of the temporomandibular joint, or if the traction force it experiences exceeds its tolerable limit, the finite element calculation should be terminated; similarly, if the force, torque, or movement of at least one tooth during the wearing process exceeds its tolerable limit, the finite element calculation should be terminated. Figure 14 The stress-deformation curves and corresponding deformation limits of different orthodontic appliance materials are shown. If the shape of the orthodontic appliance changes beyond the deformation limit of the material used during wear, phenomena such as appliance breakage will occur, and finite element calculations should be stopped at this time.

[0075] The evaluation unit is used to assess the distribution of orthodontic forces on various parts of the jaw during and after the wearing process, as obtained from simulation, and to determine whether it meets the orthodontic prescription and biomechanical constraints. In a preferred embodiment of this application, the biomechanical constraints include the maximum orthodontic force that each tooth can withstand, the maximum arch expansion force that the maxilla and / or mandible can withstand, the maximum traction force that the condyle can withstand, and the maximum spatial range of condylar movement.

[0076] Specifically, in some embodiments, the evaluation unit can compare the simulated orthodontic force distribution with the orthodontic forces required to be applied to various parts of the jaw to achieve the orthodontic purpose as described in the orthodontic prescription, in order to determine whether the requirements of the orthodontic prescription can be met after wearing the alternative appliance. At the same time, the evaluation unit also judges whether the orthodontic forces applied to various parts of the jaw during the entire wearing process exceed the above-mentioned biomechanical limits, so as to avoid potential discomfort or pain that may be caused by wearing the alternative appliance.

[0077] The simulation results can be evaluated in various ways. For example, the orthodontic force distribution obtained from the simulation results can be displayed simultaneously with the target orthodontic force recorded in the orthodontic prescription to show the difference. Alternatively, a corresponding scoring table can be established to accumulate the scores of the candidate orthodontic appliances by summing up the various orthodontic force deviations. Those skilled in the art can also use other methods to evaluate the above simulation results.

[0078] If, after evaluation, the simulation results are determined to meet the orthodontic prescription and biomechanical constraints, the candidate orthodontic appliance digital model can be identified as the digital model for orthodontic use, and the appliance can then be manufactured using this digital model. If the evaluation results do not meet the requirements, the candidate orthodontic appliance digital model can be optimized, and the optimized model can be re-simulated using the simulation unit. Furthermore, if the simulation results deviate significantly from the orthodontic prescription, a new search can be performed using the search unit.

[0079] The display unit is used to visually display the aforementioned dynamic digital model of the jaw, digital models of alternative orthodontic appliances, the wearing process, and the distribution of orthodontic forces. Various display terminals can serve as the display unit. For example, in some embodiments of this application, the display unit may include the screen of a desktop computer or laptop computer, a smart tablet, a smartphone, an AR / VR device, etc., and the information is displayed visually on the display terminal in the form of a graphical user interface. In some embodiments of this application, the displayed content can also be interactively controlled by operating a mouse, keyboard, or through touch, gestures, voice, etc. Furthermore, in some preferred embodiments of this application, the display unit can also synchronously display orthodontic prescriptions or medical records on the display device.

[0080] Figure 15 A schematic diagram of a graphical user interface 700 displayed on a display unit in a specific embodiment is shown. For example... Figure 15As shown, the graphical user interface 700 includes multiple tabs 701 that can be switched to display different content. In this embodiment, tab 701 displays a specific dynamic digital dental model 400. Through the window 702 on the left, the corresponding patient identity information, orthodontic prescription, and medical records can be provided. In addition, through the operation controls 703 below, the mandibular model 420 of the dynamic digital dental model 400 can be interactively controlled to perform various biting movements relative to the maxillary model 410, or videos of the mandibular model 420 performing various biting movements relative to the maxillary model 410 can be played.

[0081] The specific embodiments of this application have been described in detail above. For those skilled in the art, several improvements and modifications can be made to this application without departing from the principle of this application, and these improvements and modifications also fall within the protection scope of the claims of this application.

Claims

1. A system for evaluating and displaying orthodontic force on an orthodontic appliance, used to evaluate and display the orthodontic force experienced by the teeth after wearing an orthodontic appliance and to obtain a digital model of the orthodontic appliance used for orthodontics, characterized in that, The orthodontic force includes the corrective force on at least one tooth, the corrective force on the maxilla and / or mandible, and the traction force on the condyle. The orthodontic force assessment and display system includes: The preprocessing unit is used to preprocess orthodontic data to generate a dynamic digital model of the jaw. The dynamic digital model of the jaw is generated based on the actual occlusal relationship of the upper and lower jaws. The actual occlusal relationship includes the movement parameters of the condyle during the occlusal process, specifically including the inclination angle and / or movement trajectory curve of the condyle during the occlusal process. The retrieval unit is used to retrieve candidate orthodontic appliance digital models from the database based on the dynamic dental digital model and orthodontic prescription. The candidate orthodontic appliance digital model includes an upper alveolar and a lower alveolar formed by an outer wall, an inner wall, and an occlusal pad connecting the inner wall and the outer wall. The upper alveolar is formed by the inner surface of the upper part of the outer wall, the inner surface of the upper part of the inner wall, and the upper surface of the occlusal pad. The lower alveolar is formed by the inner surface of the lower part of the outer wall, the inner surface of the lower part of the inner wall, and the lower surface of the occlusal pad. The simulation unit uses the dynamic dental digital model and the alternative orthodontic appliance digital model to simulate the wearing process using the finite element method. It determines the wearing parameters and the distribution of orthodontic forces at any time during the simulation, and obtains the distribution of orthodontic forces after the dental appliance is worn based on the simulation. The wearing parameters include the condyle's motion parameters during the wearing process, specifically including the condyle's motion trajectory tilt angle and / or motion trajectory curve during the wearing process. The evaluation unit is used to evaluate whether the distribution of the orthodontic force meets the orthodontic prescription and biomechanical constraints. If the evaluation result is met, the digital model of the candidate orthodontic appliance is determined as the digital model of the orthodontic appliance used for orthodontics. If the evaluation result is not met, the digital model of the candidate orthodontic appliance is optimized and re-simulated by the simulation unit or re-searched by the retrieval unit. The display unit is used to visually display the dynamic digital model of the jaw, the digital model of the alternative orthodontic appliance, the wearing process, and the distribution of the orthodontic force.

2. The orthodontic force assessment and display system for an orthodontic appliance according to claim 1, characterized in that, The preprocessing unit includes: The data retrieval module is used to retrieve orthodontic data from the database. The orthodontic data includes a digital model of the dentition to be treated, the actual occlusal relationship of the dentition to be treated, and the orthodontic prescription. The positioning and binding module positions and binds the digital model of the dentition to be treated to the actual occlusal relationship in order to generate a dynamic digital model of the dentition.

3. The orthodontic force assessment and display system for an orthodontic appliance according to claim 1, characterized in that, The actual bite relationship also includes: The relative positional relationship between the upper and lower jaws in a non-occlusal state and the relative positional relationship between the upper and lower jaws in an occlusal state.

4. The orthodontic force assessment and display system for an orthodontic appliance according to claim 1, characterized in that, The dynamic dental digital model and the orthodontic appliance digital model are digital finite element models, and the simulation unit includes: The constitutive parameter setting module is used to set the finite element constitutive parameters of the dynamic dental digital model and the alternative orthodontic appliance digital model; The calculation parameter setting module is used to set the finite element calculation parameters; The initial state setting module is used to set the initial values ​​of the wearing parameters; The finite element calculation module, based on the initial values ​​of the wearing parameters and the calculation parameters, simulates the wearing process using the finite element calculation method to determine the wearing parameters and the distribution of the orthodontic force at any time during the simulation.

5. The orthodontic force assessment and display system for an orthodontic appliance according to claim 4, characterized in that, The finite element constitutive parameters include: Material parameters, element parameters, and model type.

6. The orthodontic force assessment and display system for an orthodontic appliance according to claim 4, characterized in that, The wearing parameters also include: The morphology of the digital model of the candidate orthodontic appliance, the morphology of the dynamic dental digital model, the relative positional relationship between the digital model of the candidate orthodontic appliance and the dynamic dental digital model during the wearing process, and the biting force of the upper and lower jaws during the wearing process.

7. The orthodontic force assessment and display system for an orthodontic appliance according to claim 4, characterized in that: The finite element method described uses a nonlinear calculation method.

8. The orthodontic force assessment and display system for an orthodontic appliance according to claim 7, characterized in that, The calculation parameters include: Contact and boundary conditions between the digital model of the alternative orthodontic appliance and the dynamic digital model of the dentition.

9. The orthodontic force assessment and display system for an orthodontic appliance according to claim 8, characterized in that: The boundary conditions include the loading speed.

10. The orthodontic force assessment and display system for an orthodontic appliance according to claim 9, characterized in that: The loading speed is 0.001 m / s to 3 m / s; The calculation parameters also include damping parameters.

11. The orthodontic force assessment and display system for an orthodontic appliance according to claim 1, characterized in that, The distribution of the orthodontic force includes: The magnitude and direction of orthodontic forces acting on at least one part of a dynamic digital model of the dentition.

12. The orthodontic force assessment and display system for an orthodontic appliance according to claim 1, characterized in that, Optimizing the digital model of the candidate orthodontic appliance specifically involves adjusting the shape of the digital model of the candidate orthodontic appliance or adjusting at least one of the following parameters: The initial values ​​of the finite element constitutive parameters, the finite element calculation parameters, and the wearing parameters.

13. The orthodontic force assessment and display system for an orthodontic appliance according to claim 1, characterized in that, The biomechanical constraints include at least one of the following constraints: The maximum orthodontic force that each tooth can withstand, the maximum arch expansion force that the maxilla and / or mandible can withstand, the maximum traction force that the condyle can withstand, and the maximum range of space for condyle movement.

14. The orthodontic force assessment and display system for an orthodontic appliance according to claim 1, characterized in that: The preprocessing unit also includes a precision adjustment module for adjusting the model precision of the dynamic dental digital model.

15. The orthodontic force assessment and display system for an orthodontic appliance according to claim 1, characterized in that, The display unit includes one or more of the following devices: Display terminals for desktop and laptop computer screens, smart tablets, smartphones, and AR / VR devices.

16. The orthodontic force assessment and display system for an orthodontic appliance according to claim 1, characterized in that: The actual occlusal relationship is obtained by measuring the teeth to be treated using an articulator.

Images