Temporomandibular Joint Motion Reconstruction Method Based on Multimodal Information Fusion

Abstract

The present invention provides a method for reconstructing temporomandibular joint movement based on multimodal information fusion, which is characterized by: making upper and lower jaw marking devices; collecting and processing mandibular movement data; collecting and processing CBCT data images; fusing mandibular movement data and CBCT image data; making multi-jaw position occlusal splints; collecting and processing MRI data images; registering and fusing mandibular movement data with CBCT and MRI image data steps to visually reproduce mandibular movement in the form of 3D models and images. The present invention realizes accurate recording of the relative movement relationship and spatial posture of the temporomandibular joint fossa, articular disc, and condyle, reveals the true functional movement state of the temporomandibular joint in an intuitive and quantitative form. This method can be used in clinical research of the temporomandibular joint, as an auxiliary means for the diagnosis, treatment, and prognosis evaluation of temporomandibular joint diseases. The clinical operation is simple, which can reduce the difficulty of clinicians in judging the position of the articular disc and improve the accuracy of the diagnosis and treatment of temporomandibular joint diseases.

Description

Technical Field

[0001] The present invention relates to the field of temporomandibular joint movement reconstruction, and specifically to a temporomandibular joint movement reconstruction method based on multimodal information fusion. Background Art

[0002] In recent years, multimodal information fusion technology has received extensive attention in the medical field. Among them, medical image fusion can combine different imaging data, make full use of the advantages of various medical information, and display anatomical structures, functional states, etc. in multiple aspects in a single image, thus providing more comprehensive physiological or pathological information in an intuitive form and providing technical means for the accurate diagnosis and treatment of oral-related diseases.

[0003] Currently, the commonly used auxiliary examination techniques for the temporomandibular joint are radiography and mandibular movement tracing techniques. At present, only by collecting static image data can the radiography technique obtain high-quality images. The dynamic image has low resolution and is only two-dimensional imaging. Any single imaging technique cannot obtain its complete structural and disease information and cannot intuitively reflect the real-time state of its functional movement. Due to reasons such as mechanical tracing, the yieldability of soft tissues, and in-situ measurement, the mandibular movement tracing technique has insufficient measurement accuracy and cannot directly record and observe the movement of internal structures. It can only combine anatomical knowledge to infer the coordinated movement state of the temporomandibular joint and other soft tissues based on the movement trajectory curve. Some domestic and foreign researchers combine binocular vision and CT technology, which can only show the movement of the bony tissue of the temporomandibular joint and lack the important movement reconstruction of the temporomandibular joint disc, which is far from enough for the research of the temporomandibular joint. At present, there is no system or product that can completely reconstruct the movement process of the temporomandibular joint. Oral doctors urgently need to intuitively understand the real-time functional state of the temporomandibular joint, which has become one of the urgent problems to be solved in the current research on temporomandibular joint diseases. Summary of the Invention

[0004] The purpose of the present invention is to provide a temporomandibular joint movement reconstruction method based on multimodal information fusion. The steps of the temporomandibular joint movement reconstruction method include:

[0005] Step 1: Make upper and lower jaw marking devices;

[0006] Step 2: Mandibular movement data acquisition and processing: An optical positioning and tracking system is used to record the mandibular movement of the trial wearer. The trial wearer wears upper and lower jaw marking devices and sits upright on a chair with back support, looking straight ahead, facing the optical positioning and tracking system, with the orbital-auricular plane parallel to the horizontal plane. The trial wearer performs relevant mandibular movements according to the doctor's instructions, and the optical positioning and tracking system records the movement data of the marking points on the upper and lower jaw marking devices in real time. When the upper and lower jaw bone marking devices enter the cone of vision of the optical positioning and tracking system, the transformation matrix from the optical positioning and tracking system to the coordinate system of the marking device and the movement data of the marking balls are directly obtained;

[0007] Step 3: CBCT data image acquisition and processing: The craniofacial CBCT data of the trial wearer in the intercuspal position wearing the upper and lower jaw marking devices is collected. Image processing algorithms are used to segment and three-dimensionally reconstruct the upper and lower jaws, and the relative positional relationships between the maxilla and the upper jaw marking device and between the mandible and the lower jaw marking device are calibrated;

[0008] Step 4: Fusion of mandibular movement data and CBCT image data: The movements of the upper and lower jaw marking devices obtained are converted into the movements of the upper and lower jaws, and the three-dimensional reconstruction models of the upper and lower jaws are used to reproduce the mandibular movement;

[0009] Step 5: Fabrication of multi-jaw occlusal splints: During the mandibular movement of the three-dimensional models of the upper and lower jaws, anatomical occlusal splints are designed and 3D printed based on the three-dimensional reconstruction models corresponding to multiple jaw positions to ensure that the fossa-disc-condyle relationship during the acquisition of MRI data is consistent with the sitting position during the acquisition of CBCT data;

[0010] Step 6: MRI data image acquisition and processing: The trial wearer wears the occlusal splint and undergoes MRI examination of the temporomandibular joint area. The MRI image data of the temporomandibular joint in multiple jaw positions is collected, and image processing algorithms are used to three-dimensionally reconstruct the structures of the articular fossa, articular disc, and condyle;

[0011] Step 7: Registration and fusion of mandibular movement data with CBCT and MRI image data: A registration method guided by anatomical structures is used to perform image registration on the CBCT and MRI images and three-dimensional reconstruction files, and the mandibular movement data is combined and converted into the movements of the temporomandibular joint fossa, articular disc, and condyle to obtain a dynamic video composed of a set of images and a set of three-dimensional reconstruction model frame sequences, thereby obtaining the functional movement conditions of the temporomandibular joint.

[0012] Furthermore, the steps of fabricating the upper and lower jaw marking devices include:

[0013] Step 11: The maxillary marking device uses a face-bow type bracket as the main structure. Slideways and nut structures are designed at both left and right ends of the bracket. Two headbands are respectively arranged at the front and rear ends on both the left and right sides of the bracket. The left and right headbands are bonded with Velcro to play a fixing role, and four passive reflective marking balls I are bonded to the marking frame of the face-bow type bracket;

[0014] Step 12: The mandibular marking device uses a personalized mandibular dental arch splint type occlusal fork as the main structure. A marking frame is provided at the end of the occlusal fork, and four passive reflective marking balls II identical to those of the maxillary marking device are bonded;

[0015] Step 13: Wear the upper and lower jaw marking devices with reflective marking balls for the test wearer: First, wear the maxillary marking device with four passive reflective marking balls I bonded. Use silicone rubber impression material to make a nasal support and place it between the nasion of the test wearer and the connecting body of the two lens rings of the maxillary marking device. Adjust the distance between the left and right fixing frames so that it closely adheres to the left and right sides of the volunteer's head without compression. After adjusting the upper and lower edges of the device to be parallel to the pupil connection line, fix it with two headbands that cross over the top of the head and under the occipital bone. Adjust the pre-made personalized mandibular dental arch splint type occlusal fork so that there is no interference during the mandibular movement of the test wearer. Fix it to the lower dentition with bioadhesive, and ensure that its handle is consistent with the midfacial line. Fix the marking frame with four reflective marking balls II at the predetermined position.

[0016] Further, both the reflective marking ball I and the reflective marking ball II are used to be recognized by the optical positioning and tracking system.

[0017] Further, the personalized mandibular dental arch splint type occlusal fork in Step 12 is composed of a front dental arch splint and a handle.

[0018] Further, both the reflective marking ball I and the reflective marking ball II are made of ABS material and have an infrared reflective coating.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0020] Through steps such as transformation, segmentation, and registration, the present invention fuses the mandibular movement data obtained by the optical positioning and tracking system with the CBCT and MRI image data of the temporomandibular joint, and has the following advantages:

[0021] (1) Comprehensively and intuitively reproduce the real functional movement state of the temporomandibular joint in the form of 3D models and images, overcome the shortcomings of previous devices that can only record the movement trajectory curve or the movement of the bone tissue of the temporomandibular joint, increase the movement record of the articular disc, obtain the spatial postures and relative positional relationships of the complete internal structure of the temporomandibular joint, and can be observed from any time and spatial perspective, providing a basis for the establishment of the temporomandibular joint movement physiology and case models;

[0022] (2) Use a computer to directly obtain and calculate the relative movement of the upper and lower jaws based on kinematic algorithms, replacing the previous method of using a tracing needle to find the patient's hinge axis position, simplifying the experimental operation process, reducing the impact on the results caused by equipment interference, subjective cognitive biases of operators, and unskilled operation techniques, and improving the accuracy of recording and measurement;

[0023] (3) Realize registering multiple jaw position MRI images with only one CBCT scan, reducing the radiation dose received by the patient and lowering the image acquisition cost;

[0024] (4) The device designed in the present invention has adjustability, can be reused multiple times, has a wide range of applications, and reduces the production cost;

[0025] (5) As an auxiliary means for the diagnosis, treatment, and prognosis evaluation of temporomandibular joint diseases, it is easy to operate, reduces the difficulty for clinicians to judge the position of the articular disc, and improves the accuracy of the diagnosis and treatment of temporomandibular joint diseases. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is a schematic flow chart of the present invention;

[0027] Figure 2 is a front view of the upper jaw marking device of the present invention;

[0028] Figure 3 is a top view of the upper jaw marking device of the present invention;

[0029] Figure 4 is a right view of the upper jaw marking device of the present invention;

[0030] Figure 5 is a front view of the lower jaw marking device of the present invention;

[0031] Figure 6 is a top view of the lower jaw marking device of the present invention;

[0032] Figure 7 is a right view of the lower jaw marking device of the present invention;

[0033] Figure 8 is a schematic structural diagram of the upper and lower jaw marking device of the present invention;

[0034] Figure 9 is a schematic diagram of the lower jaw opening and closing movement data of the present invention.

[0035] The reference numerals and names in the drawings are as follows:

[0036] 1. Bracket; 2. First reflection marking ball; 3. Marking frame; 4. Second reflection marking ball; 5. Handle; 6. Dental arch splint. DETAILED DESCRIPTION OF THE INVENTION

[0037] As shown in the appendix Figure 1 The method for reconstructing temporomandibular joint movement based on multimodal information fusion provided by the present invention, the steps of the temporomandibular joint movement reconstruction method include:

[0038] Step 1: Fabricate the upper and lower jaw marking devices:

[0039] Step 11, as shown in the appendix Figure 2 and 3 and Figure 4, the upper jaw marking device uses a facebow-type bracket as the main structure. Slideways and nut structures are designed at both left and right ends of the bracket 1. Two headbands are respectively arranged at the front and rear ends on the left and right sides of the bracket 1, and the left and right headbands are bonded with Velcro to play a fixing role. Four passive reflective marking balls 1-2 are bonded to the marking frame of the facebow-type bracket for identification by the optical positioning and tracking system. The reflective marking ball 1-2 is made of ABS material and has an infrared reflective coating;

[0040] Step 12, as shown in the appendix Figure 5 and 6 and Figure 7, the lower jaw marking device uses a personalized lower dental arch splint-type occlusal fork as the main structure. The personalized lower dental arch splint-type occlusal fork is composed of a front dental arch splint 6 and a handle 5. A marking frame 3 is provided at the end of the occlusal fork, and four passive reflective marking balls 2-4 identical to those of the upper jaw marking device are adhered. The reflective marking ball 2-4 is also made of ABS material and has an infrared reflective coating;

[0041] The preparation steps of the dental arch splint and the handle are as follows: Take a plaster model of the lower dentition of the test wearer, make a lower dentition pressure membrane retainer, grind the area where it has occlusal contact with the upper dentition to obtain the dental arch splint, and connect a handle at the labial side position of the lower central incisor to facilitate holding and fixing the marking frame;

[0042] Step 13, as shown in the appendix Figure 8 and Figure 8, wear the upper and lower jaw marking devices with reflective marker balls on the test wearer: First, wear the upper jaw marking device with four passive reflective marker balls 1-2 adhered. Use silicone rubber impression material to make a nose pad and place it between the nasion of the test wearer and the connecting body of the two lens rings of the upper jaw marking device. Adjust the distance between the left and right fixing frames so that it closely adheres to the left and right sides of the volunteer without compression. After adjusting the upper and lower edges of the device to be parallel to the pupil connection line, use two headbands that cross over the top of the head and below the occipital bone to fix it. Adjust the pre-made personalized lower dental arch splint-type occlusal fork so that there is no interference when the test wearer makes mandibular movements, and fix it to the lower dentition with bioadhesive, and ensure that its handle 5 is consistent with the midfacial line, and fix the marking frame with four reflective marker balls 2-4 adhered at the predetermined position.

[0043] Step 2: Acquisition and processing of mandibular movement data: An optical positioning and tracking system is used to record the mandibular movement of the trial wearer. The trial wearer wears upper and lower jaw marking devices and sits upright on a chair with back support, looking straight ahead, facing the optical positioning and tracking system, with the orbitomeatal plane parallel to the horizontal plane. The trial wearer performs relevant mandibular movements according to the doctor's instructions, and the optical positioning and tracking system records the movement data of the marking points on the upper and lower jaw marking devices in real time. When the upper and lower jaw bone marking devices enter the cone range of the optical positioning and tracking system, the transformation matrix from the optical positioning and tracking system to the coordinate systems of the upper and lower jaw marking devices is directly obtained. and the movement data of the marking balls Pt(x, y, z);

[0044] Coordinate system establishment: In the present invention, the world reference coordinate system is defined as W = {O W , X W , Y W , Z W}, the coordinate system of the upper jaw marking device is defined as the coordinate system of the lower jaw marking device is defined as the coordinate system of the upper jaw bone is defined as U = {O U , X U , Y U , Z U}, the coordinate system of the lower jaw bone is defined as L = {O L , X L , Y L , Z L}, and the coordinate system of the articular disc is defined as C = {O C , X C , Y C , Z C}; where the origin of the coordinate system of the upper jaw bone is the nasion, the sagittal direction is defined as the X-axis, the horizontal direction is defined as the Y-axis, and the vertical direction is defined as the Z-axis, which is parallel to each corresponding coordinate axis in the coordinate systems of the lower jaw bone and the articular disc.

[0045] The optical positioning system obtains mandibular movement data: When the upper and lower jaw bone marking devices enter the cone range of the optical positioning and tracking system, the spatial coordinates Pt(x, y, z) of the marking point P of the upper and lower jaw marking devices in the world coordinate system at time t are obtained, and the spatial coordinates Pu1(t), Pu2(t), Pu3(t), Pu4(t) of the marking point group of the upper jaw marking device and the spatial coordinates Pl1(t), Pl2(t), Pl3(t), Pl4(t) of the marking point group of the lower jaw marking device at time t.

[0046] Step 3: CBCT data image acquisition and processing: Collect craniofacial CBCT data of the intercuspal position of the test wearer wearing the upper and lower jaw marking devices, segment and three-dimensionally reconstruct the upper and lower jaws using image processing algorithms, and calibrate the relative positional relationships between the maxilla and the upper jaw marking device and between the mandible and the lower jaw marking device to obtain the transformation matrix and

[0047] Step 4: Fusion of mandibular movement data and CBCT image data: Convert the movements of the acquired upper and lower jaw marking devices into the movements of the upper and lower jaws to realize the reproduction of mandibular movement in the three-dimensional reconstruction models of the upper and lower jaws;

[0048] Specifically, by using the method of marking CBCT images, the center positions of the four reflective balls on the upper and lower jaw marking devices are obtained, and the coordinate systems UM and LM of the upper and lower jaw marking devices are established based on the positions of the four ball centers. Since the CBCT image data includes both the upper and lower jaws and the upper and lower jaw marking devices, the conversion relationships between the coordinate systems of the upper and lower jaws and the coordinate systems of the upper and lower jaw marking devices are obtained and According to the coordinate system transformation matrix of the optical positioning and tracking system and the upper and lower jaw marking devices and the obtained movement data, the conversion relationships between the coordinate systems of the upper and lower jaws and the coordinate system of the optical positioning and tracking system can be obtained and Thus, the registration and fusion of CBCT image data and mandibular movement data are realized.;

[0049] As shown in the appendix Figure 9 the mandibular opening and closing movement data are obtained, where X is the sagittal condylar displacement; Y is the horizontal condylar displacement; Z is the vertical condylar displacement; S is the spatial condylar displacement;

[0050] Normal range of mandibular movement of the temporomandibular joint: It should reach 10 - 14 mm during protrusive movement, and 10 - 16 mm during opening and closing movement; during lateral movement, the mandibular movement should be within the range of 8 - 12 mm.

[0051] Step 5: Fabricate multi-jaw occlusal splints: During the mandibular movement of the three-dimensional models of the upper and lower jaws, select the three-dimensional reconstruction models corresponding to multiple jaw positions to design and 3D print anatomical occlusal splints to ensure that the fossa-disc-condyle relationship during MRI data acquisition is consistent with that in the sitting position during CBCT data acquisition;

[0052] Step 6: MRI data image acquisition and processing: The test wearer wears the occlusal splint to perform MRI examinations of the temporomandibular joint area, collect MRI image data of the temporomandibular joint at multiple jaw positions, and three-dimensionally reconstruct the structures of the articular fossa, articular disc, and condyle using image processing algorithms;

[0053] Step 7: Registration and fusion of mandibular movement data with CBCT and MRI image data: Using a registration method guided by anatomical structures, image registration is performed on CBCT and MRI images and three-dimensional reconstruction files. By combining the mandibular movement data to transform into the movement of the temporomandibular joint fossa, articular disc, and condyle, a dynamic video composed of a set of images and a set of three-dimensional reconstruction model frame sequences is obtained, thereby obtaining the functional movement of the temporomandibular joint. Specifically, it includes:

[0054] (1) Image registration: Identify the condyle and fossa images in CBCT and MRI images respectively and perform feature extraction. Align the two images spatially so that the surface edge contours of the fossa and condyle in CBCT and MRI images are consistent and completely coincide, with no overlap at the edges, obtaining the registration matrix of CBCT and MRI images, and performing image fusion into a CBCT-MRI image;

[0055] (2) Model registration: Identify the cortical contour of the condyle in the three-dimensional reconstruction models of CBCT and MRI images respectively and perform feature extraction. Align the two images spatially to obtain the registration matrix of CBCT and MRI three-dimensional reconstruction models, and perform image fusion into a CBCT-MRI three-dimensional reconstruction model;

[0056] (3) According to the conversion relationship between the optical positioning tracking system coordinate system and CBCT and the registration conversion relationship between CBCT and MRI, the conversion relationship between the optical positioning tracking system coordinate system and MRI is obtained, and then the spatial position of the articular disc during mandibular movement is obtained, thereby obtaining the functional movement of the temporomandibular joint.

[0057] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0058] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "upper", "lower", "inner", "outer", "front end", "rear end", "both ends", "one end", "the other end", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0059] In the description of the present invention, it should be noted that, unless otherwise clearly defined and limited, terms such as "installed", "equipped with", "connected", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

Claims

1. A method for temporomandibular joint movement reconstruction based on multimodal information fusion, characterized in that: The steps of the temporomandibular joint movement reconstruction method include: Step 1: Fabricate the upper and lower jaw marking devices: Step 2: Acquisition and processing of mandibular movement data: Use an optical positioning and tracking system to record the mandibular movement of the test wearer. The test wearer wears the upper and lower jaw marking devices and sits upright on a chair with back support, looking straight ahead, facing the optical positioning and tracking system, with the Frankfurt horizontal plane parallel to the horizontal plane. The test wearer performs relevant mandibular movements according to the doctor's instructions. The optical positioning and tracking system records the movement data of the marking points on the upper and lower jaw marking devices in real time. When the upper and lower jaw bone marking devices enter the cone of vision of the optical positioning and tracking system, the transformation matrix from the optical positioning and tracking system to the coordinate system of the marking device and the movement data of the marking balls are directly obtained; Step 3: Acquisition and processing of CBCT data images: Acquire the craniofacial CBCT data of the test wearer in the intercuspal position while wearing the upper and lower jaw marking devices. Use image processing algorithms to segment and three-dimensionally reconstruct the upper and lower jaws, and calibrate the relative positional relationships between the maxilla and the maxillary marking device, and between the mandible and the mandibular marking device; Step 4: Fusion of mandibular movement data and CBCT image data: Convert the movements of the obtained upper and lower jaw marking devices into the movements of the upper and lower jaws to realize the reproduction of the mandibular movement by the upper and lower jaw three-dimensional reconstruction models; Step 5: Fabricate multi-jaw occlusal splints: During the mandibular movement of the upper and lower jaw three-dimensional models, select the three-dimensional reconstruction models corresponding to multiple jaw positions to design and 3D print anatomical occlusal splints to ensure that the fossa-disc-condyle relationship during the acquisition of MRI data is the same as that in the sitting position when CBCT data is acquired; Step 6: Acquisition and processing of MRI data images: The test wearer wears the occlusal splint for MRI examination of the temporomandibular joint area, acquires the MRI image data of the temporomandibular joint at multiple jaw positions, and uses image processing algorithms to three-dimensionally reconstruct the structures of the articular fossa, articular disc, and condyle; Step 7: Registration and fusion of mandibular movement data with CBCT and MRI image data: Adopt a registration method guided by anatomical structures to perform image registration on the CBCT and MRI images and three-dimensional reconstruction files, and combine the mandibular movement data to be converted into the movements of the temporomandibular joint fossa, articular disc, and condyle to obtain a dynamic video composed of a set of images and a set of three-dimensional reconstruction model frame sequences, so as to obtain the functional movement conditions of the temporomandibular joint, specifically including: (1) Perform image registration on the CBCT and MRI images; (2) Perform model registration on the three-dimensional reconstruction models of the CBCT and MRI images; (3) According to the conversion relationship between the coordinate system of the optical positioning and tracking system and the CBCT, and the registration conversion relationship between the CBCT and MRI, obtain the conversion relationship between the coordinate system of the optical positioning and tracking system and the MRI, and further obtain the spatial position of the articular disc during mandibular movement, so as to obtain the functional movement conditions of the temporomandibular joint.

2. The method for temporomandibular joint movement reconstruction based on multi-modal information fusion according to claim 1, wherein: The steps of fabricating the upper and lower jaw marking devices include: Step 11: The maxillary marking device uses a face-bow type bracket as the main structure. Slideways and nut structures are designed at both left and right ends of the bracket. Two headbands are respectively arranged at the front and rear ends on both left and right sides of the bracket. The left and right headbands are bonded with Velcro to play a fixing role, and 4 passive reflective marker balls are bonded to the marking frame of the face-bow type bracket. Step 12: The mandibular marking device uses a personalized mandibular dental arch splint type occlusal fork as the main structure. A marking frame is provided at the end of the occlusal fork, and 4 passive reflective marker balls identical to those of the maxillary marking device are bonded. Step 13: Wear the maxillary and mandibular marking devices with reflective marker balls for the trial wearer: First, wear the maxillary marking device with 4 passive reflective marker balls bonded. Use silicone rubber impression material to make a nasal support and place it between the nasion of the trial wearer and the connecting body of the two lens rings of the maxillary marking device. Adjust the distance between the left and right fixing frames so that it closely adheres to the left and right sides of the volunteer without compression. After adjusting the upper and lower edges of the device to be parallel to the pupil line, fix it with two headbands that cross over the head and under the occipital bone. Adjust the pre-made personalized mandibular dental arch splint type occlusal fork so that there is no interference during the mandibular movement of the trial wearer. Fix it to the lower dentition with bioadhesive and ensure that its handle is consistent with the midfacial line. Fix the marking frame with 4 marker balls at the predetermined position.

3. The method for temporomandibular joint movement reconstruction based on multimodal information fusion according to claim 2, characterized in that: The 4 passive reflective marker balls in Step 11 are used to be recognized by the optical positioning and tracking system.

4. The method for temporomandibular joint movement reconstruction based on multimodal information fusion according to claim 2, wherein: The personalized mandibular dental arch splint type occlusal fork in Step 12 consists of a front dental arch splint and a handle.

5. The method for reconstructing temporomandibular joint movement based on multi-modal information fusion according to claim 2, wherein: The reflective marker ball is made of ABS material and has an infrared reflective coating.

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