Virtual reality technology-based edentulous jaw implantation operation teaching system and method thereof

Abstract

The invention provides an edentulous jaw implantation operation teaching system and method based on a virtual reality technology, and the teaching system is a tooth implantation operation training system based on a VR technology, and comprises a personal model module, a virtual operating room module, a user interaction module, and an equipment display module. The personal model module is used for constructing a personalized anatomical model containing an edentulous jaw bone, a neural tube and a safety area by using CT data of a patient; the virtual operating room module builds a scene through Unity and builds a high-precision surgical instrument model through three-dimensional design software; the user interaction module is connected with the personal model module and the virtual operating room module, and integrates a collision detection algorithm in a Unity engine to realize virtual instrument interaction and feedback; the equipment display module obtains and displays operation parameters in real time through calculation and early warns risks; according to the invention, key operation parameters can be fed back in real time, students are assisted to deepen understanding of operation procedures, and practical skills and comprehensive ability are improved.

Description

Technical Field

[0001] The present invention relates to the technical fields of virtual reality technology and medical education equipment technology, in particular to an edentulous jaw implant surgery teaching system and method based on virtual reality technology, that is, an edentulous jaw implant surgery teaching system and method combining personalized modeling, real-time parameter feedback, and risk warning. Background Art

[0002] With the increasing aging of the global population, the number of edentulous patients has increased, and the demand for edentulous jaw implant surgery has been growing. Edentulous jaw implant surgery involves complex anatomical structures such as the nerve canal, etc., with high surgical operation difficulty and extremely high requirements for doctors' professional skills. However, traditional dental teaching methods, such as head model simulation and observational learning, have many limitations. These methods are difficult to truly restore the dynamics of the clinical surgical scene and patient individual differences. Students lack sufficient practical operation opportunities and cannot obtain real-time feedback during the learning process, making it difficult to effectively transform theoretical knowledge into practical operation skills, resulting in poor training effects and unable to meet the needs of modern dental education for high-quality teaching.

[0003] With the continuous development of VR technology, its application in the education field has been gradually widespread. VR technology can create an immersive virtual environment, making users feel as if they are on the scene, providing a new opportunity to solve the problems in dental teaching. Currently, although there have been some application studies of VR technology in the dental field, the VR system for edentulous jaw implant surgery teaching is still imperfect, with problems such as insufficiently realistic simulation scenarios, insufficiently rich interaction functions, and inability to accurately evaluate surgical operations, and further improvement and innovation are urgently needed. Summary of the Invention

[0004] The present invention proposes an edentulous jaw implant surgery teaching system and method based on virtual reality technology, integrating modeling and interaction technologies to create an immersive training environment. This system can provide real-time feedback on key surgical parameters, helping students deepen their understanding of the surgical process and improve their practical skills and comprehensive abilities.

[0005] The present invention adopts the following technical solutions.

[0006] Toothless jaw implant surgery teaching system based on virtual reality technology. The teaching system is a tooth implant surgery training system based on VR technology, including a personal model module, a virtual operating room module, a user interaction module, and a device display module. The personal model module constructs a personalized anatomical model containing the edentulous jawbone, nerve canal, and safe area using the patient's CT data. The virtual operating room module builds a scene through Unity and constructs high-precision surgical instrument models using 3D design software. The user interaction module connects the personal model module and the virtual operating room module, and integrates a collision detection algorithm in the Unity engine to achieve virtual instrument interaction and feedback. The device display module calculates and displays surgical parameters in real time and warns of risks.

[0007] The personal model module uses Mimics software to perform threshold segmentation, cavity filling, and three-dimensional reconstruction on DICOM-format CT data to generate an edentulous jaw model containing the nerve canal orientation and safe area division.

[0008] The edentulous jaw model separates the nerve canal from the jawbone through Boolean operations and uses the plane cutting function to divide the surgical safe area, non-safe area, and dangerous area.

[0009] In this method, the virtual operating room module constructs high-precision surgical instrument models using SolidWorks software. The user interaction module connects to virtual reality devices based on SteamVR.

[0010] The surgical instrument models in the virtual operating room module include precision drills, guide drills, spiral step drills, implants, and cover screws, and the precision error of the surgical instrument models is less than 0.1 mm.

[0011] The user interaction module connects to HTC VIVE devices through the SteamVR protocol.

[0012] In the teaching system, the personalized model module: is used to obtain the patient's CT image data, and perform three-dimensional reconstruction through the medical image processing software Mimics and the 3D scanning analysis software Geomagic wrap to generate a personalized anatomical model containing the edentulous jawbone, nerve canal, and safe area division;

[0013] The virtual operating room module: constructs an immersive virtual environment containing an operating table, an instrument trolley, and virtual surgical tools. The virtual surgical tools include a round bur, a pilot drill, a reamer, a tapping drill, a depth gauge, a holder, and a cover screw;

[0014] The user interaction module: integrates a head-mounted display device and a handle controller, and realizes the picking up, assembling, and operation of virtual instruments through a collision detection algorithm, and real-time feedback on the position and angle of the instruments;

[0015] Equipment display module: displays surgical parameters in real time, including the distance between the instrument tip and the nerve canal, implantation angle and parallelism, and provides operation risk warnings through the UI interface.

[0016] The virtual instrument interaction and feedback method of the edentulous jaw implant surgery teaching system based on virtual reality technology, the specific method of realizing collision detection and assembly in Unity is executed by combining C# code with Unity's physics engine to realize the dynamic assembly, disassembly and parameter feedback functions of surgical instruments, as follows:

[0017] Method 1: Design collision body components. Specifically, in the user interaction module, add Box Collider components to different surgical instruments (such as turbines and drills) and combine them with Rigidbody components to implement physical collision detection. The collision body is used to trigger assembly and disassembly logic;

[0018] Method 2: Set the collision trigger logic OnTriggerEnter, specifically: when different surgical instruments (such as turbine Object B and drill Object A) come into contact, the OnTriggerEnter function in the C# script (belonging to the MonoBehaviour class of Unity) is triggered to detect the contact event; align the local coordinate system of Sphere A and Sphere B with the world coordinate system through the preset feature objects, and establish a parent-child relationship through C# code (for example, set the drill as the child object of the turbine) to achieve the assembly effect;

[0019] Method 3: Coordinate system alignment algorithm, specifically: calculate the position and rotation difference of collision-related components (turbine and drill bit); move Sphere A to the position of Sphere B, and synchronously adjust the position of related components (such as the drill bit); align the local x-axis of Sphere A with the local x-axis of Sphere B through rotation operation to ensure that the directions of related components (such as the drill bit and turbine) are consistent;

[0020] Method 4: disassembly logic implementation, specifically: when the assembled instrument contacts the preset "disassembly area" (ObjectC), the collision detection is triggered, the parent-child relationship of the assembly process is released through the code, and the assembly-related components (drill bit) are restored to the initial position and rotation state so that the new instrument can be replaced;

[0021] Method 5: Real-time parameter verification, specifically: In the device display module, use the ClosestPoint function of the collision body to calculate the closest distance between the model components to be verified (for example, between the tip of the drill bit ObjectA and the neural tube plane Object C), and verify whether it meets the safety standard (such as distance > 2mm) through the Euclidean distance formula. At the same time, calculate the pose of the model components to be verified for verification (for example, the angle between the drill bit and the vertical vector to ensure that the implantation angle error is within 5°).

[0022] In the above-mentioned Method 5, the device display module uses the following algorithms:

[0023] Distance verification algorithm: Calculate the Euclidean distance between the tip of the dental drill and the closest point on the surface of the neural tube. If the distance is less than 2mm, an alarm will be triggered;

[0024] Angle verification algorithm: Evaluate the perpendicularity of the dental drill to the jaw plane through the vector angle formula. If the deviation exceeds 5°, the operation is determined to be incorrect;

[0025] When the edentulous jaw implant surgery teaching system performs virtual instrument interaction, the specific method for real-time monitoring of the angle and distance between the tip of the virtual instrument drill bit and the neural tube of the personalized anatomical model is as follows:

[0026] Angle calculation: Use the vector dot product formula to calculate the angle between the vector connecting the tip of the drill bit ObjectA and the turbine assembly point Object B and the vertical vector. The formula is as follows:

[0027]

[0028] In the formula, the vector represents the spatial connection direction from the turbine assembly point to the tip of the drill bit, which is used to describe the actual implantation path of the drill bit; the vector represents the preset ideal vertical direction. In unity, the vertical direction is the Y-axis. θ represents the angle between the two vectors, which is used to quantify the deviation between the drill bit holding direction and the target vertical direction. The ideal angle is 0°, that is, completely vertical;

[0029] When performing parameter verification on the angle, use 5° as the threshold to judge whether the implantation angle meets the clinical standard, that is, when the angle error ≤ 5°, it is regarded as qualified and the verification passes;

[0030] Distance calculation method: Obtain the closest point p of the tip of the drill bit to the surface of the neural tube through the c1osestPoint function of the collision body closest =ClosestPoint(p A ), where p A and p closest are the three-dimensional space coordinates of the tip of the drill bit and the closest point on the surface of the neural tube respectively, and apply the Euclidean distance formula to calculate the distance between the two points:

[0031]

[0032] When performing parameter verification, the verification basis is that the required distance must be ≥ 2 mm to avoid damaging the neural tube;

[0033] The real-time verification process is specifically as follows: The angle and distance parameters are synchronously displayed in the Unity UI. When the angle deviation exceeds 5° or the distance is less than 2 mm, an alarm prompt is triggered. At the same time, the detection results are updated frame by frame through the update function provided by the MonoBehaviour class of Unity to ensure real-time performance.

[0034] The method includes a training method for edentulous jaw implant surgery based on VR technology. The training method for edentulous jaw implant surgery based on VR technology includes the following steps;

[0035] Step S1: Personalized model construction, specifically including the following steps;

[0036] Step S11: Obtain the patient's CT data, import it into Mimics software for threshold segmentation (gray range 900 - 2800 Hu), and generate a jaw mask;

[0037] Step S12: Eliminate the mask holes through intelligent filling and reconstruct the three-dimensional jaw model;

[0038] Step S13: Separate the neural tube model and divide the safe area, and export it in OBJ format for Unity to call;

[0039] Step S2: Virtual surgery scene construction, specifically including the following steps;

[0040] Step S21: Import the 3D model of the operating room into Unity, and arrange the dental treatment bed, instrument trolley, and lighting equipment;

[0041] Step S22: Import the surgical tool model built by SolidWorks into the Unity resource library and bind the physical collision attributes;

[0042] Step S3: User interaction initialization, specifically including the following steps;

[0043] Step S31: Connect the HTC VIVE headset and controller, and configure the SteamVR plugin;

[0044] Step S32: Add a rigid body and a box collider to the surgical tool to implement the handle grasping and moving functions;

[0045] Step S4: Surgical operation training, specifically including the following steps;

[0046] Step S41: The operator selects a tool through the handle and proceeds with the following steps:

[0047] a. Drilling positioning: Reduce the transparency of the jawbone and use a ball drill to mark the cortical bone;

[0048] b. Reaming and shaping: Switch the drilling guide of the pioneer drill and gradually ream to the preset depth;

[0049] c. Implant placement: Adjust the implant angle to parallel arrangement and screw in the retainer;

[0050] Step S42: Real-time trigger the distance and angle verification algorithm, and if the parameters exceed the limit, prompt an error through the UI interface; Step S5: Operation evaluation and feedback, specifically including the following steps;

[0051] Step S51: The system records the operation time, the number of errors, and the implant position data;

[0052] Step S52: Generate a comprehensive score report, including operation standardization, efficiency, and risk avoidance ability.

[0053] The present invention proposes an edentulous jaw implant surgery teaching system based on VR technology, which consists of four major modules: a personalized model, a virtual operating room, user interaction, and device display. The personalized model module obtains the patient's CT data to construct a realistic 3D model; the virtual operating room module creates a real scene and meticulously models the surgical instruments; the user interaction module designs a natural and smooth human-computer interaction method; the device display module obtains the key position information of the instruments in real time. The four major modules operate in coordination, integrating modeling and interaction technologies to create an immersive training environment. This system can provide real-time feedback on key surgical parameters, helping students deepen their understanding of the surgical process, improve their practical skills, and enhance their comprehensive abilities.

[0054] Compared with the prior art, the present invention has the following beneficial effects: The VR edentulous jaw implant surgery teaching system of the present invention has significant advantages: First, it constructs a highly realistic virtual environment, generates a personalized model using the patient's CT data, combines the virtual scene and real instrument models, enhances the learning realism and interest, and helps students understand the surgical process and anatomical structure; Second, it has rich interaction functions, students can interact with the surgical instruments naturally, and can also master the assembly and disassembly methods of the instruments during operation; Third, the device display module can evaluate the operation parameters in real time, provide timely feedback to correct errors, and the system's recording and evaluation of operations help teachers provide targeted guidance and improve teaching quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] The following further details the present invention in conjunction with the drawings and specific embodiments:

[0056] Appendix Figure 1Schematic structural diagram of an edentulous jaw implant surgery teaching system and its implementation method according to an embodiment of the present invention;

[0057] Appendix Figure 2 Schematic diagram showing a three-dimensional model display of the edentulous jaw bone and its nerve canals according to an embodiment of the present invention (in the figure, area a is the three-dimensional model display of the edentulous jaw bone with intelligent expansion function, area b is the mandible and nerve canal model (only the nerve canal model) presented after Boolean operation, area c is the schematic diagram of the three-dimensional trajectory of the mandibular nerve canal presented in the jaw bone using the "Create thin structure" function, and area d is the key area of the mandibular implant surgery drawn using the "Plane cut three-dimensional object" function);

[0058] Appendix Figure 3 Schematic diagram showing a virtual operating room and its equipment display according to an embodiment of the present invention (in the figure, area a is the virtual operating room, area b is the Nobel active dental drill component toolbox, and area c is the virtual dental drill component toolbox);

[0059] Appendix Figure 4 Schematic diagram of part of the process of surgical operation training according to an embodiment of the present invention (in the figure, area a is the assembly of the dental drill and the turbine, area b is the schematic diagram of the detection of the distance and angle of the dental drill, and area c is the schematic diagram of the detection of the position and angle of the implant). Detailed implementation method

[0060] As shown in the figure, the edentulous jaw implant surgery teaching system based on virtual reality technology is a dental implant surgery training system based on VR technology, including a personal model module, a virtual operating room module, a user interaction module, and a device display module; the personal model module constructs a personalized anatomical model containing the edentulous jaw bone, nerve canals, and safety areas using patient CT data; the virtual operating room module builds a scene through Unity and constructs high-precision surgical instrument models using three-dimensional design software; the user interaction module connects the personal model module and the virtual operating room module, and integrates a collision detection algorithm in the Unity engine to achieve virtual instrument interaction and feedback; the device display module calculates and displays surgical parameters in real time and warns of risks.

[0061] The personal model module uses Mimics software to perform threshold segmentation, hole filling, and three-dimensional reconstruction on DICOM format CT data to generate an edentulous jaw model including the nerve canal trend and safety area division.

[0062] The edentulous jaw model separates the nerve canals from the jaw bone through Boolean operation, and uses the plane cutting function to divide the surgical safety area, non-safety area, and dangerous area.

[0063] In the described method, the virtual operating room module constructs a high-precision surgical instrument model using SolidWorks software; the user interaction module connects to a virtual reality device based on SteamVR.

[0064] The surgical instrument model in the virtual operating room module includes a precision drill, a guide drill, a spiral step drill, an implant, and a covering screw, and the precision error of the surgical instrument model is less than 0.1 mm.

[0065] The user interaction module connects to an HTC VIVE device through the SteamVR protocol.

[0066] In the teaching system, the personalized model module: is used to obtain the CT image data of the patient, and performs three-dimensional reconstruction through the medical image processing software Mimics and the 3D scanning analysis software Geomagic wrap to generate a personalized anatomical model including the edentulous jawbone, the nerve canal, and the safety area division;

[0067] The virtual operating room module: constructs an immersive virtual environment including an operating table, an instrument cart, and virtual surgical tools, and the virtual surgical tools include a ball drill, a pioneer drill, a reamer, a tapping drill, a depth measuring rod, a holding forceps, and a closure screw;

[0068] The user interaction module: integrates a head-mounted display device and a handle controller, realizes the picking up, assembling, and operating of virtual instruments through a collision detection algorithm, and real-time feedbacks the position and angle of the instruments;

[0069] The device display module: displays the surgical parameters in real time, including the distance between the tip of the instrument and the nerve canal, the implanting angle and parallelism of the implant, and provides an operation risk warning through the UI interface.

[0070] For the virtual instrument interaction and feedback method of the edentulous jaw implant surgery teaching system based on virtual reality technology, the specific method for realizing collision detection and assembly in Unity is executed by combining C# code with the physical engine of Unity to realize the dynamic assembly, disassembly, and parameter feedback functions of surgical instruments, specifically as follows:

[0071] Method 1. Design a collider component. Specifically: in the user interaction module, by adding a Box Collider component to different surgical instruments (such as a turbine, a drill bit), and combining with a Rigidbody component to realize physical collision detection. The collider is used to trigger the assembly and disassembly logic;

[0072] Method 2: Set the collision trigger logic OnTriggerEnter, specifically: when different surgical instruments (such as turbine Object B and drill bit Object A) come into contact, the OnTriggerEnter function in the C# script (belonging to the MonoBehaviour class of Unity) is triggered to detect the contact event; align the local coordinate systems and world coordinate systems of both by the preset feature objects Sphere A and Sphere B, and establish a parent-child relationship through C# code (such as setting the drill bit as a child object of the turbine) to achieve the assembly effect;

[0073] Method 3: Coordinate system alignment algorithm, specifically: calculate the position and rotation differences of the collision-related devices (turbine and drill bit); move Sphere A to the position of Sphere B and synchronously adjust the positions of the relevant devices (such as the drill bit); align the local x-axis of Sphere A with the local x-axis of Sphere B through rotation operations to ensure that the directions of the relevant devices (such as the drill bit and the turbine) are consistent;

[0074] Method 4: Disassembly logic implementation, specifically: when the assembled instrument contacts the preset "disassembly area" (Object C), trigger collision detection, release the parent-child relationship in the assembly process through code, and restore the assembled relevant devices (drill bit) to the initial position and rotation state for replacing new instruments;

[0075] Method 5: Real-time parameter verification, specifically: in the device display module, use the ClosestPoint function of the collider to calculate the closest distance between the model components to be verified (such as between the tip of the drill bit Object A and the neural tube plane Object C), and verify whether it meets the safety standard (such as distance > 2mm) through the Euclidean distance formula. At the same time, calculate the posture of the model components to be verified for verification (such as the angle between the drill bit and the vertical vector to ensure that the implantation angle error is within 5°).

[0076] In the above Method 5, the device display module uses the following algorithms:

[0077] Distance verification algorithm: Calculate the Euclidean distance between the tip of the dental drill and the closest point on the surface of the neural tube. If the distance is less than 2mm, trigger an alarm;

[0078] Angle verification algorithm: Evaluate the perpendicularity of the dental drill to the jaw plane through the vector angle formula. If the deviation exceeds 5°, it is determined that the operation is incorrect;

[0079] When the edentulous jaw implant surgery teaching system conducts virtual instrument interaction, the specific method for real-time monitoring of the angle and distance between the tip point of the virtual instrument drill bit and the neural tube of the personalized anatomical model is as follows:

[0080] Angle calculation: Use the vector dot product formula to calculate the angle between the vector connecting the drill tip ObjectA and the turbine assembly point Object B and the perpendicular vector. The formula is as follows:

[0081]

[0082] In the formula, the vector represents the spatial connection direction from the turbine assembly point to the drill tip, which is used to describe the actual implantation path of the drill; the vector represents the preset ideal perpendicular direction. In unity, the perpendicular direction is the Y-axis. θ represents the angle between the two vectors, which is used to quantify the deviation between the drill holding direction and the target perpendicular direction. The ideal angle is 0°, that is, completely perpendicular;

[0083] When performing parameter verification on the angle, 5° is used as the threshold to determine whether the implantation angle meets the clinical standard, that is, when the angle error ≤ 5°, it is regarded as qualified and the verification passes;

[0084] Distance calculation method: Obtain the closest point p from the drill tip to the surface of the nerve canal through the closestPoint function of the collider closest =ClosestPoint(p A ), where p A and p closest are the three-dimensional space coordinates of the drill tip and the closest point on the surface of the nerve canal respectively, and the Euclidean distance formula is applied to calculate the distance between the two points:

[0085]

[0086] In the formula, D represents the three-dimensional space distance from the drill tip to the closest point on the surface of the nerve canal, P A,x is the coordinate component of the drill tip on the X-axis, P A,y is the coordinate component of the drill tip on the Y-axis, P A,z is the coordinate component of the drill tip on the Z-axis, P closest,x is the coordinate component of the closest point on the surface of the nerve canal on the X-axis, P closest,y is the coordinate component of the closest point on the surface of the nerve canal on the Y-axis, P closest,z is the coordinate component of the closest point on the surface of the nerve canal on the Z-axis;

[0087] When performing parameter verification, the verification basis is that the distance must be ≥ 2mm to avoid damaging the nerve canal;

[0088] The specific real-time verification process is as follows: Synchronously display the angle and distance parameters in UnityUI. When the angle deviation exceeds 5° or the distance is less than 2mm, an alarm prompt is triggered. At the same time, the detection results are updated frame by frame through the update function provided by the MonoBehaviour class of Unity to ensure real-time performance.

[0089] The method includes a training method for edentulous jaw implant surgery based on VR technology, and the training method for edentulous jaw implant surgery based on VR technology includes the following steps;

[0090] Step S1: Construction of a personalized model, specifically including the following steps;

[0091] Step S11: Obtain the patient's CT data, import it into Mimics software for threshold segmentation (gray range 900 - 2800 Hu), and generate a jaw mask;

[0092] Step S12: Eliminate mask holes through intelligent filling and reconstruct a three-dimensional jaw model;

[0093] Step S13: Separate the nerve canal model and divide the safe area, and export it in OBJ format for Unity to call;

[0094] Step S2: Construction of a virtual surgery scene, specifically including the following steps;

[0095] Step S21: Import a 3D model of the operating room in Unity, and arrange a dental treatment bed, an instrument trolley, and lighting equipment;

[0096] Step S22: Import the surgical tool model constructed by SolidWorks into the Unity resource library and bind physical collision attributes;

[0097] Step S3: Initialization of user interaction, specifically including the following steps;

[0098] Step S31: Connect the HTC VIVE headset and controller, and configure the SteamVR plugin;

[0099] Step S32: Add a rigid body and a box collider to the surgical tool to achieve the functions of handle grasping and movement;

[0100] Step S4: Surgical operation training, specifically including the following steps;

[0101] Step S41: The operator selects a tool through the controller and performs the following steps:

[0102] a. Drilling positioning: Reduce the transparency of the jaw, and use a round bur to mark points on the cortical bone;

[0103] b. Reaming and shaping: Switch the drilling guide of the pioneer drill and gradually ream to the preset depth;

[0104] c. Implant insertion: Adjust the implant angle to be parallel and screw in the retainer;

[0105] Step S42: Trigger the distance and angle verification algorithm in real time. If the parameters exceed the limit, an error will be prompted through the UI interface; Step S5: Operation evaluation and feedback, which specifically includes the following steps;

[0106] Step S51: The system records the operation time, the number of errors, and the implant position data;

[0107] Step S52: Generate a comprehensive score report, including operation standardization, efficiency, and risk aversion ability.

[0108] Example 1:

[0109] Refer to Figure 1 , the present invention provides an edentulous jaw implant surgery teaching system based on VR technology, including a personal model module, a virtual operating room module, a user interaction module, and a device display module. Figure 2 The personalized model module obtains the CT data of the patient and constructs a 3D model. Figure 3 The virtual operating room module creates a virtual operating room scene and models surgical instruments. Figure 4 Design the interaction method with the instruments for the user interaction module. The device display module obtains the key position information of the instruments, and all modules are integrated to form a comprehensive teaching system. This system combines modeling and interaction technologies to create an immersive training environment. This system can provide real-time feedback on key surgical parameters, thereby improving students' understanding of the surgical process, practical skills, and overall capabilities.

[0110] The present invention demonstrates an edentulous jaw implant surgery teaching system based on VR technology, which consists of four major modules: a personalized model, a virtual operating room, user interaction, and device display. The personalized model module obtains the patient's CT data to construct a realistic 3D model; the virtual operating room module creates a real scene and meticulously models surgical instruments; the user interaction module designs a natural and smooth human-computer interaction method; the device display module obtains the key position information of the instruments in real time. The four major modules operate in coordination, integrating modeling and interaction technologies to create an immersive training environment. This system can provide real-time feedback on key surgical parameters to help students deepen their understanding of the surgical process and improve their practical skills and comprehensive capabilities.

[0111] To achieve the above object, the technical solution of the present invention is: an edentulous jaw implant surgery teaching system and method based on virtual reality, including a personal model module, a virtual operating room module, a user interaction module, and a device display module. The personalized model module obtains the CT data of the patient and constructs a 3D model. The virtual operating room module creates a virtual operating room scene and models surgical instruments. The user interaction module designs the interaction method with the instruments. The device display module obtains the key position information of the instruments, and all modules are integrated to form a comprehensive teaching system.

[0112] Personalized model module: Obtain the patient's CT data and build a 3D model. Specifically, it includes case selection and data acquisition, selecting eligible patient data from the hospital imaging database, and obtaining informed consent from the patient. The CT data is processed using software such as Mimics, Geomagic wrap, and SolidWorks. First, the DICOM file direction of the edentulous maxilla and mandible is adjusted in the Mimics software to achieve a three-dimensional effect display; the mask is generated by threshold segmentation by adjusting the image grayscale, and the mask is edited using the region selection function to remove the mask corresponding to irrelevant tissue; the cavity in the mask is filled using the automatic fill function, and finally a three-dimensional reconstruction is performed to generate a three-dimensional digital model of the jaw. When making a neural tube model, the grayscale value range and intelligent filling distance are adjusted according to its characteristics. After similar threshold segmentation, mask processing, and Boolean operations, the final mandibular model with a hollow neural tube is obtained, providing an accurate anatomical structure model for subsequent surgical simulation.

[0113] Virtual operating room module: Create a virtual operating room scene and model surgical instruments. Import and arrange basic surgical facilities in Unity, such as operating rooms, carts, and dental comprehensive treatment beds, to create an immersive virtual reality experience. Refer to surgical instruments widely used in clinical practice, such as the NobelActive dental drill component toolbox, and use SolidWorks software to create models of surgical instruments such as ball drills, pilot drills, reamer drills, tapping drills, depth measuring rods, nail holders, and closed screws, so that students can be exposed to various instruments used in real surgeries in a virtual environment.

[0114] User interaction module: Design the interaction mode with the instrument. The handle installed on the HTC VIVE virtual reality headset is used as a tool for the operator to interact with the virtual reality environment. The connection between the computer and the virtual reality headset is established through SteamVR to ensure that the computer runs as a display device in Unity. In Unity, the VIVE input utility plug-in is used to combine the rigid body and box collider components to realize the picking and moving operations of objects such as dental drills in virtual space. In order to realize the assembly and disassembly of different types of dental drills, a collision body component is designed, and the collision trigger function is realized by combining it with the collider component through C# code. When the turbine contacts the drill bit, the OnTriggerEnter function is triggered, so that the local coordinate system of the dental drill and the turbine is aligned with the world coordinate system and the parent-child relationship is maintained, so that the assembly of the dental drill is realized; when the dental drill contacts the "disassembly area", the parent-child relationship between the turbine and the dental drill is automatically released, and the disassembly operation is realized.

[0115] Device display module: Obtain the key position information of the instrument. By developing a method that combines display information with Unity UI, it can evaluate in real time whether the operation skills of the operator meet the required parameters. Design two indicators to measure the implanting posture of the operator. One is to calculate the vector angle between the tip of the dental drill and the assembly position of the turbine, and use an angle of 5° as the evaluation standard to determine whether the current grip of the dental drill meets the implanting standard; the other is to calculate the Euclidean distance between the tip of the dental drill and the plane where the nerve canal is located to ensure that the distance between the tip of the dental drill and the nerve canal is greater than 2 mm. For the case of multiple implants, design an algorithm for determining the angles of various implants to help the operator control the implanting angle, ensure the parallelism between implants, and improve the success rate of implant surgery.

[0116] A virtual edentulous jaw implant surgery teaching system based on VR technology and its implementation method, characterized by including the following steps: Step S1: Personalized model construction

[0117] S11: Obtain the patient's CT data, import it into Mimics software for threshold segmentation (gray scale range 900 - 2800 Hu), and generate a jaw mask;

[0118] S12: Eliminate the mask holes through intelligent filling and reconstruct the three-dimensional jaw model;

[0119] S13: Separate the nerve canal model and divide the safe area, and export it in OBJ format for Unity to call;

[0120] Step S2: Virtual surgery scene construction

[0121] S21: Import the 3D model of the operating room into Unity, and arrange the dental treatment bed, instrument cart and lighting equipment;

[0122] S22: Import the surgical tool model built by SolidWorks into the Unity resource library and bind the physical collision attributes;

[0123] Step S3: User interaction initialization

[0124] S31: Connect the HTC VIVE headset and controller, and configure the SteamVR plugin;

[0125] S32: Add a rigid body and a box collider to the surgical tool to implement the handle grabbing and moving functions;

[0126] Step S4: Surgical operation training

[0127] S41: The operator selects a tool through the controller and performs the following steps:

[0128] a. Drilling positioning: Reduce the transparency of the jaw bone and mark the cortical bone with a round bur;

[0129] b. Reaming and forming: Switch the drilling guide of the pioneer drill and gradually ream the hole to the preset depth;

[0130] c. Implant placement: Adjust the implant angle to parallel arrangement and screw in the retainer;

[0131] S42: Real-time trigger the distance and angle verification algorithm, and prompt an error through the UI interface if the parameters exceed the limit; Step S5: Operation evaluation and feedback

[0132] S51: The system records the operation time, the number of errors, and the implant position data;

[0133] S52: Generate a comprehensive score report, including operation standardization, efficiency, and risk avoidance ability.

Claims

1. A teaching system for edentulous implant surgery based on virtual reality technology, characterized in that: The teaching system is a dental implant surgery training system based on VR technology, including a personal model module, a virtual operating room module, a user interaction module, and a device display module. The personal model module constructs a personalized anatomical model containing edentulous jaws, nerve canals, and safety areas using patient CT data. The virtual operating room module builds a scene through Unity and constructs high-precision surgical instrument models using 3D design software. The user interaction module connects the personal model module and the virtual operating room module, and integrates a collision detection algorithm in the Unity engine to achieve virtual instrument interaction and feedback. The device display module calculates and displays surgical parameters in real time and warns of risks.

2. The edentulous jaw implant surgery teaching system based on virtual reality technology according to claim 1, wherein: The personal model module uses Mimics software to perform threshold segmentation, hole filling, and 3D reconstruction on CT data in DICOM format to generate an edentulous jaw model containing the nerve canal orientation and safety area division.

3. The edentulous jaw implant surgery teaching system based on virtual reality technology according to claim 1, characterized in that: The edentulous jaw model separates the nerve canal from the jaw through Boolean operations and uses the plane cutting function to divide the surgical safety area, non-safety area, and danger area.

4. The edentulous jaw implant surgery teaching system based on virtual reality technology according to claim 1, wherein: In the method, the virtual operating room module constructs high-precision surgical instrument models using SolidWorks software; the user interaction module is based on SteamVR to connect virtual reality devices.

5. The edentulous jaw implant surgery teaching system based on virtual reality technology according to claim 4, wherein: The surgical instrument models in the virtual operating room module include precision drills, guide drills, spiral step drills, implants, and covering screws, and the precision error of the surgical instrument models is less than 0.1 mm.

6. The edentulous jaw implant surgery teaching system based on virtual reality technology according to claim 4, characterized in that: The user interaction module connects to the HTC VIVE device through the SteamVR protocol.

7. The edentulous jaw implant surgery teaching system based on virtual reality technology according to claim 4, wherein: In the teaching system, the personalized model module: is used to obtain patient CT image data, and performs 3D reconstruction through the medical image processing software Mimics and the 3D scanning analysis software Geomagic wrap to generate a personalized anatomical model containing edentulous jaws, nerve canals, and safety area division; the virtual operating room module: constructs an immersive virtual environment containing an operating table, an instrument cart, and virtual surgical tools, and the virtual surgical tools include a round bur, a pilot drill, a reamer, a tapping drill, a depth gauge, a holder, and a cover screw; The user interaction module: integrates a head-mounted display device and a handle controller, and realizes the picking up, assembling, and operation of virtual instruments through a collision detection algorithm, and real-time feedback on the position and angle of the instruments; The device display module: displays surgical parameters in real time, including the distance between the instrument tip and the nerve canal, the implant insertion angle and parallelism, and provides an operation risk warning through the UI interface.

8. Virtual instrument interaction and feedback method of an edentulous jaw implant surgery teaching system based on virtual reality technology, characterized in that: The specific method for implementing collision detection and assembly in Unity is executed by combining script code with the physical engine of Unity to achieve the dynamic assembly, disassembly, and parameter feedback functions of surgical instruments, as follows: Method 1: Design a collider component. Specifically: in the user interaction module, by adding a BoxCollider component to different surgical instruments and combining it with the Rigidbody component to achieve physical collision detection. The collider is used to trigger the assembly and disassembly logic; Method 2: Set the collision trigger logic OnTriggerEnter. Specifically, when different surgical instruments come into contact, the function in the script is triggered to detect the contact event. The local coordinate systems of Sphere A and Sphere B are aligned with the world coordinate system through the preset feature objects, and the parent-child relationship is established through the code to achieve the assembly effect. Method 3: Coordinate system alignment algorithm, specifically: calculate the position and rotation difference of collision-related components; move Sphere A to the position of Sphere B, and adjust the position of related components synchronously; align the local x-axis of Sphere A with the local x-axis of Sphere B through rotation operation to ensure that the directions of related components are consistent; Method 4: disassembly logic implementation, specifically: when the assembled device contacts the preset "disassembly area", the collision detection is triggered, the parent-child relationship of the assembly process is released through the code, and the assembly-related components are restored to the initial position and rotation state so that new devices can be replaced; Method 5: Real-time parameter verification, specifically: in the device display module, use the ClosestPoint function of the collision body to calculate the closest distance between the model components to be verified, and verify whether it meets the safety standards through the Euclidean distance formula. At the same time, calculate the posture of the model components to be verified for verification.

9. The virtual instrument interaction and feedback method of the edentulous jaw implant surgery teaching system based on virtual reality technology according to claim 8, characterized in that: In the fifth method, the device display module uses the following algorithm: distance verification algorithm: calculates the Euclidean distance between the tip of the dental drill and the closest point on the surface of the nerve canal, and triggers an alarm if the distance is less than 2 mm; Angle verification algorithm: The verticality between the dental drill and the jaw plane is evaluated through the vector angle formula. If the deviation exceeds 5°, it is considered an operation error. When the edentulous jaw implant surgery teaching system is interacting with virtual instruments, the angle and distance of the drill tip of the virtual instrument relative to the neural canal of the personalized anatomical model are monitored in real time. The specific method is as follows: Angle calculation: Use the vector dot product formula to calculate the angle between the vector connecting the drill tip Object A and the turbine assembly point Object B and the vertical vector. The formula is as follows: In the formula, the vector represents the spatial connection direction from the turbine assembly point to the drill bit tip, and is used to describe the actual implantation path of the drill bit; Vector represents a preset ideal vertical direction. In Unity, the vertical direction is the Y-axis. θ represents the angle between the two vectors, which is used to quantify the deviation between the holding direction of the dental drill and the target vertical direction. The ideal angle is 0°, that is, completely vertical; When verifying the angle parameters, 5° is used as the threshold to determine whether the implantation angle meets the clinical standard. That is, when the angle error is ≤5°, it is considered qualified and the verification is passed. Distance calculation method: Obtain the closest point p from the drill bit tip to the surface of the nerve canal through the closestPoint function of the collider closest = ClosestPoint(p A ), where p A and p closest are the three-dimensional space coordinates of the drill bit tip and the closest point on the surface of the nerve canal respectively, and the Euclidean distance formula is applied to calculate the distance between the two points: Wherein, D represents the three-dimensional spatial distance from the tip of the dental drill to the nearest point on the surface of the nerve canal, P A,x is the coordinate component of the tip of the dental drill on the X-axis, P A,y is the coordinate component of the tip of the dental drill on the Y-axis, P A,z is the coordinate component of the tip of the dental drill on the Z-axis, P closest,x is the coordinate component of the nearest point on the surface of the nerve canal on the X-axis, P closest,y is the coordinate component of the nearest point on the surface of the nerve canal on the Y-axis, P closest,z is the coordinate component of the nearest point on the surface of the nerve canal on the Z-axis; When performing parameter verification, the verification basis is that the distance must be ≥2 mm to avoid damaging the neural tube; The specific real-time verification process is as follows: the angle and distance parameters are displayed synchronously in UnityUI, and an alarm is triggered when the angle deviation exceeds 5° or the distance is less than 2mm. At the same time, the update function provided by Unity's MonoBehaviour class is used to update the detection results frame by frame to ensure real-time performance.

10. The virtual instrument interaction and feedback method of the edentulous jaw implant surgery teaching system based on virtual reality technology according to claim 8, characterized in that: The method includes a VR-based edentulous jaw implant surgery training method, and the VR-based edentulous jaw implant surgery training method includes the following steps: Step S1: Personalized model construction, specifically The steps include: Step S11: Obtain patient CT data, import it into Mimics software for threshold segmentation, and generate a jaw mask; Step S12: eliminating mask holes through intelligent filling and reconstructing a three-dimensional jaw model; Step S13: Separate the neural tube model and divide the safe area, and export it in OBJ format for Unity to call; Step S2: Set up the virtual surgery scene, which specifically includes the following steps; Step S21: Import the 3D model of the operating room in Unity, and arrange the dental treatment bed, instrument cart and lighting equipment; Step S22: Import the surgical tool model built by SolidWorks into the Unity resource library and bind the physical collision attributes; Step S3: Initialize user interaction, which specifically includes the following steps; Step S31: Connect the HTC VIVE headset and controller, and configure the SteamVR plugin; Step S32: Add a rigid body and a box collider to the surgical tool to achieve the functions of grabbing and moving the controller; Step S4: Surgical operation training, which specifically includes the following steps; Step S41: The operator selects the tool through the controller and performs the following steps: a. Drilling positioning: Reduce the transparency of the jawbone and mark the cortical bone with a round bur; b. Reaming and shaping: Switch the drilling guide of the pilot drill and gradually ream to the preset depth; c. Implant placement: Adjust the angle of the implant to be parallel and screw in the retainer; Step S42: Real-time trigger the distance and angle verification algorithm, and if the parameters exceed the limit, prompt an error through the UI interface; Step S5: Operation evaluation and feedback, which specifically includes the following steps; Step S51: The system records the operation time, the number of errors and the implant position data; Step S52: Generate a comprehensive score report, including operation standardization, efficiency and risk avoidance ability.

Images