Jaw function as guide bone cement interposition digital guide plate and manufacturing method
By using a functionally guided digital guide plate for placement between bone cement and mandibular bone defects, the problems of poor repair precision and malocclusion in mandibular bone defect repair have been solved, achieving high-precision mandibular bone defect repair and ensuring complete fit between the prosthesis and the bone surface and functional adaptation.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- THE SECOND AFFILIATED HOSPITAL ARMY MEDICAL UNIV
- Filing Date
- 2026-05-26
- Publication Date
- 2026-07-21
Smart Images
Figure CN122423935A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of jawbone defect repair technology in oral and maxillofacial surgery, and particularly to a digital guide plate for jaw function-guided placement of bone cement and its manufacturing method. Background Technology
[0002] Mandibular defects are a common clinical condition in oral and maxillofacial surgery, often caused by factors such as extensive tumor resection, infection, and comminuted trauma to the maxillofacial region. They not only lead to facial deformities but also directly disrupt core oral physiological functions such as chewing, swallowing, and speech, causing severe physical trauma and psychological distress. Currently, the gold standard for mandibular defect repair is vascularized autologous bone grafting. While this technique can achieve structural repair of bone defects, it has inherent drawbacks such as significant secondary damage to the donor site, complex surgical procedures, and a high dependence on the surgeon's clinical experience and hospital resources. This makes it difficult to promote and apply in primary healthcare institutions, and it is unsuitable for emergency treatment needs in battlefield environments or sudden disasters. Traditional free bone grafting is strictly limited by factors such as defect length and the risk of infection in the surgical area, resulting in extremely poor adaptability to irregular curved mandibular defects. Postoperative complications such as nonunion, malocclusion, and facial deformities are common, severely limiting its clinical application.
[0003] Induced membrane technology is a technique that uses a bone cement intercalator to induce the formation of a bioactive membrane cavity in the body, followed by the secondary implantation of bone graft material to repair bone defects. It boasts advantages such as ease of operation, minimal invasiveness, no limitation on defect length, and strong resistance to infection, and has been widely used in the repair of long bone defects. However, its clinical application in mandibular defect repair is extremely limited. The core reason is that the mandible is an irregular three-dimensional curved bony structure that simultaneously serves as a facial support structure and transmits occlusal function. The regular columnar repair logic for long bone defects cannot be directly applied. Existing hand-shaped bone cements suffer from poor morphological accuracy, insufficient fit to the bone fragment, and inability to meet occlusal function requirements, leading to postoperative complications such as infection, nonunion, and poor osteogenesis. In response, Chinese patent CN111544079A discloses a method for constructing an individualized mandibular defect reconstruction guide system. This system designs a mandibular reconstruction guide based on CT data, enabling guide-assisted positioning during autologous bone graft reconstruction.
[0004] However, the guide plate system built by this scheme only serves the implantation and fixation of autologous bone flaps in a single surgery. The entire reconstruction operation is completed once the surgical procedure is finished. For the second-stage cancellous bone filling of the induction membrane technology, the operation can only be completed by visual observation and tactile estimation. When faced with the irregular three-dimensional curved membrane cavity formed in areas such as the body and angle of the mandible, the volume calculation error is extremely large. This either increases the trauma range of autologous bone harvesting or leaves ineffective cavities in the membrane cavity. It is difficult to accurately control the total filling amount and distribution pattern. The uncontrollability of the filling process directly affects the stable reservation of space required for subsequent occlusal function reconstruction. Implant restoration sets strict thresholds for the vertical height of new bone, buccal-lingual width, and axial direction of the implantation site. Fluctuations in the filling volume directly cause a significant shift in the morphology of new bone. Either the bone volume parameters fail to meet the basic threshold for implant restoration, or the bone bulges and compresses soft tissue and occludes occlusal space. This design only refers to the left-right symmetry of the mandibular anatomical contour, deviating from the core design reference of the occlusal relationship of the opposing teeth. It is difficult to match the site requirements for the transmission of masticatory function, ultimately making the space reservation required for functional restoration completely unfounded. Meanwhile, the guide system adopts a split design, with the osteotomy guide and the fixation guide each having independent fixation points. When changing the guide during the operation, the switching of fixation points will cause a reference shift. Under the irregular curved surface structure of the mandible, the sub-millimeter-level shift of the fixation point will be directly transmitted to the millimeter-level deviation of the bone alignment. When the osteotomy range deviates from the preoperative simulation during the operation, the fit between the prefabricated guide and the bone surface decreases, and the tilting and displacement during the fixation process will amplify the alignment deviation during the operation. This multi-stage deviation forms a superimposed effect, causing the shape and function of the reconstructed mandible to fail to meet expectations. For example, the left and right symmetry of the face decreases, the occlusal contact relationship is disordered, and the fit of the bone fragments is insufficient, making it difficult for the precision of the entire reconstruction operation to meet the clinical needs of mandibular morphology and functional reconstruction.
[0005] In summary, there is an urgent need for a function-guided digital guide plate for inter-cement bone placement that can improve the accuracy of restorations, as well as a method for its fabrication. Summary of the Invention
[0006] This invention provides a digital guide plate for jaw function-guided placement of bone cement and its manufacturing method, which can improve the accuracy of repair.
[0007] To solve the above-mentioned technical problems, this application provides the following technical solution:
[0008] A method for fabricating a digital guide plate for jaw function-guided interosseous placement includes the following steps:
[0009] S1. Data acquisition: Images of the mandibular bone defect area of the patient are acquired through maxillofacial CT scan to obtain raw DICOM data of maxillofacial CT.
[0010] S2. Model reconstruction: Threshold segmentation and three-dimensional reconstruction are performed on the original DICOM data of the maxillofacial CT to obtain a three-dimensional digital model of the mandible.
[0011] S3. Defect calibration: Based on the cause of the defect, perform corresponding preprocessing on the three-dimensional digital model of the mandible and extract the full-dimensional feature parameters of the defect area.
[0012] S4. Positioning deviation control: The three-dimensional digital model of the mandible and the full-dimensional feature parameters of the defect area are processed by the unified benchmark positioning rules. The same set of fixing holes penetrating the mandible are generated on the osteotomy guide plate, the gap maintenance guide plate, and the bone cement interposition shaping guide plate to obtain the basic model of the first phase of the collaborative guide plate group.
[0013] S5. Functional space reservation: Guided by jaw function reconstruction, the parameters of the basic model of the first-phase collaborative guide plate group are optimized, and the molding cavity height of the bone cement interposition shaping guide plate is adjusted to obtain the final digital model of the first-phase collaborative guide plate group.
[0014] S6. Quantitative filling control: Using the original DICOM data of the maxillofacial CT collected twice after the first-stage surgery, a three-dimensional digital model of the hardened bone cement interstitial placement is reconstructed. Based on this model, a three-sided closed and one-sided open cancellous bone quantitative filling guide is designed to ensure that the inner cavity of the cancellous bone quantitative filling guide is completely matched with the shape of the bone cement interstitial placement, thus obtaining the digital model of the second-stage filling guide.
[0015] S7. Guide plate preparation: The final digital model of the first-phase synergistic guide plate group and the digital model of the second-phase filling guide plate are processed into physical objects using additive manufacturing technology to obtain the physical objects of the first-phase synergistic guide plate group and the physical objects of the quantitative filling guide plate for cancellous bone.
[0016] The basic principles and beneficial effects of this approach are as follows: In this approach, a unified benchmark positioning rule is used to fundamentally control positioning deviations. The three-dimensional digital model of the mandible and the full-dimensional feature parameters of the defect area are processed. The same set of fixation holes penetrating the mandible is generated on the osteotomy guide, the gap maintenance guide, and the bone cement interposition material shaping guide. This allows the three types of guides to share a single intraoperative positioning benchmark. Intraoperative guide replacement does not require re-drilling and repositioning. Structurally, this eliminates the benchmark offset and misalignment problems caused by independent positioning of multiple guides. It ensures that the first-stage collaborative guide group is completely in contact with the mandibular bone surface and that the bone cement interposition material is closely matched with the bone fracture end. This eliminates problems such as prosthesis offset and residual gaps on the bone surface caused by positioning errors. It builds a stable and reliable positioning foundation for high-precision repair throughout the entire process and avoids the precision loss caused by intraoperative operations from the source.
[0017] Based on precise positioning, the functional space is precisely reserved with jaw function reconstruction as the guide. The parameters of the basic model of the first-stage collaborative guide plate group are optimized, and the molding cavity height of the bone cement interposition shaping guide plate is adjusted so that the shape of the bone cement interposition placement is perfectly matched with the defect area and oral anatomy. This not only ensures the healing requirements of tension-free suturing of the oral mucosa, but also reserves reasonable space for subsequent dentition restoration. It avoids the problems of poor fit and functional deviation caused by insufficient or excessive space reservation in traditional restorations. The shape and function of the restoration are precisely matched, which strengthens the core support for restoration accuracy. Based on the precise design of the preceding steps, the quantitative filling of cancellous bone is achieved through a quantitative filling guide plate. Based on the original DICOM data of the maxillofacial CT scan acquired in the second postoperative period, a three-dimensional digital model of the hardened bone cement interpositional spacer is reconstructed. The inner cavity of the guide plate designed based on this model is perfectly matched with the shape of the bone cement interpositional spacer. The structure of three closed sides and one open side can precisely limit the filling volume, distribution pattern and filling boundary of cancellous bone, avoiding the waste of bone resources and soft tissue compression caused by overfilling, or the dead space and poor osteogenesis caused by underfilling. This ensures that the bone regeneration morphology in the second stage is highly consistent with the preoperative design, eliminates all error sources in the filling process, and guarantees the quality and morphological accuracy of osteogenesis.
[0018] In summary, this approach achieves precise matching across all dimensions, including the shaping of bone cement placement, bone fragment fitting, cancellous bone osteoogenesis, and jaw function reconstruction. It improves the morphological accuracy, functional fit, and clinical stability of mandibular defect repair, enabling personalized and high-precision mandibular defect repair goals.
[0019] Furthermore, in step S1, the maxillofacial CT scan simultaneously acquires images of the patient's corresponding dentition and opposing dentition, and the original DICOM data of the maxillofacial CT includes information on dentition and occlusal relationship.
[0020] The beneficial effects are: incorporating the dentition and occlusal relationship into the basic data collection scope, providing complete data support for the design of jaw function-oriented guide plates, and avoiding deviations in the matching of restorations and occlusal function due to data loss.
[0021] Furthermore, in step S2, the original DICOM data of the maxillofacial CT is imported into computer-aided design software, and after threshold segmentation and three-dimensional fitting processing, a quantifiable three-dimensional digital model of the mandible is obtained.
[0022] The beneficial effects are: clarifying the standardized processing procedure for model reconstruction, accurately restoring the anatomical morphology of the mandible with professional software, eliminating invalid image interference, and enabling the model to have accurate measurement and editing attributes.
[0023] Furthermore, in step S3, the corresponding preprocessing is as follows: for tumor or infectious defects, osteotomy boundary marking is completed, and for traumatic fracture defects, fracture reduction simulation is completed.
[0024] The beneficial effects are: matching exclusive pre-treatment logic to different defect causes, adapting to various clinical defect scenarios, making the extraction of full-dimensional feature parameters of the defect area more in line with the actual surgery, and ensuring that the guide plate design is highly matched with the needs of clinical operation.
[0025] Furthermore, in step S4, the osteotomy guide plate is an arc-shaped plate structure that conforms to the surface of the mandible, and the same set of fixing holes penetrating the mandible are evenly distributed on the osteotomy guide plate body.
[0026] The beneficial effects are: limiting the arc-shaped fit structure and the distribution of fixation holes of the osteotomy guide plate, making the guide plate fit more closely with the mandibular bone surface, making the fixation points more stable, enhancing the reliability of the unified positioning benchmark, and reducing the positioning deviation of the osteotomy operation.
[0027] Furthermore, in step S4, the gap maintaining guide plate has a frame-shaped structure, the inner contour of which matches the boundary of the defect area, and it shares the same set of fixation holes with the osteotomy guide plate.
[0028] The beneficial effects are: clearly defining the frame structure and contour matching relationship of the gap maintenance guide plate, which can not only accurately maintain the shape of the defect gap, but also share the positioning benchmark, avoid gap deviation, and provide stable spatial constraints for the shaping of the bone cement interposition.
[0029] Furthermore, in step S5, the bone cement interstitial shaping guide plate is provided with a groove-shaped forming cavity, the contour of which is adapted to the shape of the defect area.
[0030] The beneficial effects are: the grooved molding cavity structure of the shaping guide plate for the bone cement interposition allows the bone cement to be precisely shaped along the molding cavity, ensuring that the shape of the interposition is completely matched with the defect area, and improving the shaping accuracy and fit of the bone cement interposition.
[0031] Furthermore, in step S6, the quantitative filling guide plate for cancellous bone is a groove-shaped structure with three closed sides and one open side, and its inner cavity contour is perfectly matched with the shape of the material placed between the hardened bone cement.
[0032] The beneficial effects are: clarifying the groove-shaped structural characteristics of the quantitative filling guide plate for osteoporosis, the three-sided closed structure can accurately limit the filling range and volume, and the one-sided open structure facilitates intraoperative filling operations, realizing quantitative and controllable filling of cancellous bone and ensuring the accuracy of secondary osteogenic morphology.
[0033] Furthermore, in step S7, the first-phase collaborative guide plate group entity includes an osteotomy guide plate entity, a gap maintenance guide plate entity, and a bone cement interposition shaping guide plate entity, and the structure of each guide plate entity is completely consistent with the corresponding digital model.
[0034] The beneficial effects are: clarifying the consistency of the composition and structure of the first-phase collaborative guide plate group, the division of labor of the three types of guide plate entities covering the entire repair process, constructing a precise matching design model, and ensuring that the use of guide plates during the operation is without deviation.
[0035] A digital guide plate for jaw function-guided placement of bone cement in the bone cement space includes a primary synergistic guide plate assembly and a quantitative bone cancellous filling guide plate;
[0036] The first-phase collaborative guide plate assembly consists of an osteotomy guide plate, a gap maintenance guide plate, and a bone cement interposition shaping guide plate. The osteotomy guide plate, gap maintenance guide plate, and bone cement interposition shaping guide plate have the same set of aligned fixing holes that penetrate the mandible, forming a common positioning structure for interchangeable assembly. The osteotomy guide plate is an arc-shaped plate structure that conforms to the surface of the mandible. The gap maintenance guide plate adopts a frame-shaped enclosure structure and forms a nested limiting fit with the outer contour of the defect area. The bone cement interposition shaping guide plate has a groove-shaped molding cavity that is aligned and adapted to the shape of the defect area.
[0037] The quantitative filling guide plate for cancellous bone is a U-shaped groove structure with three closed sides and one open side. The inner wall of the quantitative filling guide plate for cancellous bone forms a fully enclosed and limiting fit with the shape of the material placed between the hardened bone cement.
[0038] The beneficial effects are as follows: This scheme sets up a common reference alignment and matching structure within the first-stage collaborative guide plate group. The osteotomy guide plate, gap maintenance guide plate, and bone cement interposition shaping guide plate achieve common positioning and assembly by relying on mutually aligned fixing holes. Each functional guide plate can be quickly interchanged and installed based on the same reference, eliminating the alignment offset caused by fixing the separate guide plates one by one, avoiding the cumulative deviation caused by multiple clamping, and effectively controlling intraoperative positioning deviation. At the same time, relying on the arc-shaped plate and frame-shaped enclosed adaptation structure, the guide plate as a whole conforms to the anatomical shape of the mandible and the defect boundary, improving the stability of guide plate placement.
[0039] The bone cement interpositional placement shaping guide has a built-in integrated groove-shaped molding cavity. Relying on the alignment and fit between the cavity contour and the defect area, it provides rigid constraints on the bone cement shaping process, avoiding morphological deviations inherent in manual shaping. The overall shape of the interpositional placement can be rationally adjusted according to the needs of jaw function reconstruction, precisely reserving space for soft tissue healing and subsequent occlusal restoration. This avoids problems such as excessive mucosal tension and occlusal interference caused by unbalanced space, enhancing the functional fit accuracy of the restorative structure. The accompanying cancellous bone quantitative filling guide uses a U-shaped groove limiting structure, with a three-sided closed boundary defining the filling range. Combined with the limiting fit between the inner cavity and the hardened bone cement interpositional placement, it strictly constrains the volume and spread of cancellous bone filling, achieving quantitative controllability during the filling process. This prevents problems such as dead space and osteogenic deformities caused by redundant or insufficient filling, ensuring a regular and uniform morphology of the secondary bone regeneration tissue.
[0040] In summary, this solution utilizes a unified positioning and matching structure, a personalized shaping and limiting structure, and a quantitative filling and constraint structure to form a structural linkage, reducing human intervention and random errors, improving the fit of bone fragments, the matching degree of the prosthesis, and the stability of bone formation, thereby enhancing the overall precision of mandibular bone defect repair. Attached Figure Description
[0041] Figure 1 A flowchart of a method for fabricating a digital guide plate for inter-cement bone placement guided by jaw function.
[0042] Figure 2 A front view of a digital guide plate for jaw function-oriented placement of bone cement in the bone cement space;
[0043] Figure 3 Rear view of a digital guide plate for placement of bone cement in the jawbone, designed for jaw function;
[0044] Figure 4 A schematic diagram of a guide plate for quantitative filling of cancellous bone. Detailed Implementation
[0045] The following detailed description illustrates the specific implementation method:
[0046] Explanation of the diagram labels in the instruction manual: 1. Osteotomy guide plate; 2. Space maintenance guide plate; 3. Bone cement interposition shaping guide plate; 4. Cancellous bone quantitative filling guide plate.
[0047] Example 1
[0048] This embodiment discloses a method for fabricating a digital guide plate for mandibular function-guided placement of bone cement, applied in clinical settings for segmental bone defect repair after resection of benign mandibular tumors. All operational steps strictly adhere to clinical guidelines for oral and maxillofacial surgery and medical guide plate design standards, as shown in the attached figure. Figure 1 As shown, the specific implementation process is as follows:
[0049] S1. Data Acquisition: A 64-slice spiral CT scanner is used to perform continuous tomographic scanning of the patient's maxillofacial region, covering the entire area from the skull base to the lower edge of the mandible. During the scanning process, complete images of the patient's mandibular defect area, corresponding dentition, and opposing dentition are acquired simultaneously. The raw DICOM data of the maxillofacial CT is obtained, which fully contains information on the patient's dentition and the occlusal relationship between the upper and lower jaws, providing a standardized basic data source for the subsequent full-process guide design.
[0050] S2. Model Reconstruction: The original DICOM data of the maxillofacial CT obtained in step S1 is imported into the medical 3D visualization computer-aided design software Mimics21.0. First, grayscale threshold segmentation processing is performed on the image data. The segmentation threshold range for bone tissue is set to 226HU~3071HU, and the segmentation threshold range for soft tissue is -200HU~225HU. Irrelevant tissue images such as cervical spine and skull are removed by region growing algorithm, and the contour boundaries of mandible and dentition are accurately extracted. Then, the extracted contours are smoothed, holes are repaired, and coordinates are calibrated by 3D fitting processing. Finally, a 3D digital model of mandible that can be accurately quantified and freely edited is obtained, providing a precise 3D carrier for subsequent defect calibration and guide plate design.
[0051] S3. Defect Marking: In this embodiment, the cause of the mandibular bone defect is a benign tumor in the body of the mandible. Based on this cause, the corresponding pre-processing is performed on the three-dimensional digital model of the mandible: the safe osteotomy boundary for tumor resection is marked on the three-dimensional model, ensuring that the osteotomy boundary is ≥5mm away from the edge of the tumor tissue, and the extent of the defect area formed after osteotomy is clearly defined. After completing the pre-processing, the software's three-dimensional measurement tools are used to extract the full-dimensional feature parameters of the defect area, including its location, three-dimensional shape, boundary range, linear dimensions, and the angle and morphology of the bone fragments, providing a precise design basis for personalized guide plate design. For the application scenario of traumatic fracture defects, the corresponding pre-processing in this step is: to perform virtual reduction simulation on the displaced fracture fragments, restore the fracture segments to their normal anatomical positions, and then extract the full-dimensional feature parameters of the defect area.
[0052] S4. Positioning Deviation Control: A unified benchmark positioning rule is used to collaboratively process the three-dimensional digital model of the mandible and the full-dimensional feature parameters of the defect area. Specifically, this unified benchmark positioning rule uses three stable anatomical landmarks on the healthy side of the mandible—the mental foramen, the angle of the mandible, and the posterior border of the mandibular ramus—as the global positioning benchmark, as shown in the attached figure. Figure 2 Appendix Figure 3As shown, at the corresponding positions of the osteotomy guide plate 1, the gap maintenance guide plate 2, and the bone cement interposition shaping guide plate 3, the same set of fixation holes penetrating the healthy segment of the mandible are generated. In this embodiment, there are 3 fixation holes, each with a diameter of 2.0 mm. The holes are evenly distributed on the body of the osteotomy guide plate 1, and the fixation holes of the three guide plates are coaxially aligned with a coaxiality deviation of ≤0.05 mm, forming a common positioning structure for interchangeable assembly. The osteotomy guide plate 1 is designed as an arc-shaped plate structure that conforms to the surface of the mandible, with a plate thickness of 1.5 mm. The inner curved surface of the guide plate completely conforms to the anatomical shape of the mandibular bone surface, with a fitting gap of ≤0.1 mm. The gap maintenance guide plate 2 is designed as a frame-shaped structure, with its inner contour matching the boundary of the defect area. The frame thickness is 2.0 mm, and the gap maintenance guide plate 2 shares the same set of fixation holes as the osteotomy guide plate 1. After completing the above design, a basic model of the first-phase collaborative guide plate group is obtained.
[0053] S5. Functional Space Reservation: Guided by jaw function reconstruction, the parameters of the basic model of the first-stage collaborative guide group are optimized, and the height of the molding cavity of the bone cement interposition shaping guide 3 is adjusted. The bone cement interposition shaping guide 3 has a groove-shaped molding cavity, the contour of which is adapted to the shape of the defect area. The depth and boundary dimensions of the molding cavity are individually adjusted according to the patient's occlusal relationship, mucosal thickness, and defect range. After adjustment, the height of the molding cavity is 3-5mm lower than the corresponding area of the normal mandible on the healthy side of the patient, so as to take into account the postoperative healing requirements of tension-free suturing of the oral mucosa and the space reservation requirements for subsequent implant restoration of missing teeth. After the parameter optimization is completed, the final digital model of the first-stage collaborative guide group is obtained.
[0054] S6. Quantitative Filling Control: Four weeks after the patient completes the primary osteotomy and implantation of the interosseous bone cement implant, a second tomographic scan of the maxillofacial region is performed using CT scan parameters identical to those in step S1. The original DICOM data of the maxillofacial region acquired after the second post-operative CT scan is obtained. Using the same threshold segmentation and three-dimensional reconstruction methods as in step S2, a three-dimensional digital model of the hardened interosseous bone cement implant is reconstructed. Based solely on this three-dimensional digital model, a three-sided closed and one-sided open cancellous bone quantitative filling guide plate 4 is designed, as shown in the attached figure. Figure 4 As shown, the guide plate has a groove-shaped structure, and its inner cavity contour perfectly matches the shape of the material placed between the hardened bone cement. The guide plate has a wall thickness of 1.5 mm, with the open side facing the oral mucosa as the intraoperative filling port, and the three closed sidewalls used to define the boundary of the cancellous bone filling. After the design was completed, a digital model of the second-stage filling guide plate was obtained.
[0055] S7. Guide plate preparation: Using medical-grade photopolymerization additive manufacturing technology (SLA photopolymerization 3D printing technology), the final digital model of the first-stage synergistic guide plate group and the digital model of the second-stage filling guide plate are processed into physical objects with high precision. The printing material is medical-grade photosensitive resin conforming to YY / T0268-2008 standard, and the printing layer thickness is set to 0.05mm. After printing, the objects are sequentially subjected to anhydrous ethanol ultrasonic cleaning, ultraviolet curing, and ethylene oxide sterilization treatment, ultimately obtaining the physical objects of the first-stage synergistic guide plate group and the quantitative filling guide plate of cancellous bone. The physical objects of the first-stage synergistic guide plate group include osteotomy guide plate 1, gap maintenance guide plate 2, and bone cement interposition shaping guide plate 3. The structure and dimensions of each guide plate are completely consistent with the corresponding digital model, and the form and position tolerance is ≤0.05mm.
[0056] Example 2
[0057] This embodiment discloses a digital surgical guide for guiding bone cement placement in the jaw. This guide is a personalized surgical guide specifically for the repair of segmental defects in the mandible. It is made of medical-grade photosensitive resin that meets the clinical biosafety requirements of oral and maxillofacial surgery and includes two core components: a primary synergistic guide assembly and a quantitative bone cancellous filling guide assembly.
[0058] The first-stage collaborative guide plate assembly consists of an osteotomy guide plate 1, a gap maintenance guide plate 2, and a bone cement interposition shaping guide plate 3. The main body thickness of the three guide plates is 1.5mm, which meets the structural strength and fitting accuracy requirements of clinical surgical operations. Corresponding positions of the osteotomy guide plate 1, gap maintenance guide plate 2, and bone cement interposition shaping guide plate 3 are provided with the same set of fixation holes that are aligned with each other and penetrate the healthy bone segment of the mandible. In this embodiment, there are 3 fixation holes, each with a diameter of 2.0mm, which is completely matched with the clinically commonly used 2.0mm mandibular fixation screw size. The coaxiality deviation of the fixation holes of the three guide plates is ≤0.05mm, forming a common positioning structure that can be interchanged and assembled. During the operation, the guide plate can be replaced without re-drilling and positioning. It can be installed and fixed by using the same set of fixation screws, completely eliminating the reference offset error caused by independent positioning of multiple guide plates.
[0059] The osteotomy guide plate 1 is an arc-shaped plate structure that conforms to the surface of the mandible. Its inner curved surface completely reverses the anatomical shape of the patient's mandibular bone surface, with a fitting gap ≤0.1mm, achieving stable fitting without displacement during surgery. The osteotomy guide plate 1 is integrally provided with an osteotomy guide groove corresponding to the preoperatively marked osteotomy boundary. The guide groove width is 1.0mm, matching the size of commonly used osteotomy saw blades, which can accurately guide the osteotomy path. The gap maintenance guide plate 2 adopts a frame-shaped enclosure structure. Its inner contour forms a nested limiting fit with the outer contour of the defect area. The inner dimension of the frame structure deviates from the boundary dimension of the defect area ≤0.05mm, which can accurately fit at the positions of the bone ends on both sides of the defect area, stably maintaining the three-dimensional shape of the defect gap and avoiding displacement of the bone ends. The bone cement interposition placement shaping guide plate 3 is integrally provided with a groove-shaped forming cavity. The groove-shaped forming cavity is aligned and adapted to the shape of the defect area. The outline and depth of the forming cavity are completely consistent with the shape of the bone cement interposition placement designed before surgery. It can provide full-boundary rigid constraint on the intraoperative shaping process of bone cement, ensuring that the formed bone cement interposition placement is completely adapted to the defect area.
[0060] The bone cancellous tissue quantitative filling guide plate 4 is a U-shaped groove structure with three closed sides and one open side, as shown in the attached figure. Figure 4 As shown, the guide plate has a wall thickness of 1.5mm. The inner wall of the guide plate 4 for quantitative filling of cancellous bone forms a fully enclosed and fitted fit with the shape of the hardened bone cement interposition implanted in the first stage. The gap between the inner curved surface and the outer surface of the hardened bone cement interposition implant is ≤0.1mm. The three closed sidewalls can accurately limit the filling range and volume of cancellous bone, preventing cancellous bone overflow or insufficient filling. The one open opening faces the oral mucosa side, serving as the operation port for filling and compacting cancellous bone during the operation, which is compatible with the clinical surgical operation procedure.
[0061] In clinical use, the osteotomy guide 1 of this embodiment is first fixed to the pre-set position of the patient's mandible using fixation pins during the first-stage surgery, and precise osteotomy is performed along the osteotomy guide groove. After removing the osteotomy guide 1, without replacing the fixation pins, the gap maintenance guide 2 is directly installed and fixed through the same set of fixation holes to stably maintain the defect gap. After removing the gap maintenance guide 2, the bone cement interposition shaping guide 3 is then installed and fixed through the same set of fixation holes, and bone cement is injected into the grooved molding cavity to complete the precise shaping of the bone cement interposition. During the second-stage surgery, the bone cancellous material quantitative filling guide 4 is attached and fixed to the outside of the hardened bone cement interposition, and autologous bone cancellous material is filled into the inner cavity through the open operating port to achieve quantitative and precise filling of cancellous material.
[0062] The above are merely embodiments of the present invention. The invention is not limited to the fields covered by these embodiments. Commonly known structures and characteristics in the solutions are not described in detail here. Those skilled in the art are aware of all common technical knowledge in the field prior to the application date or priority date, are able to access all existing technologies in that field, and have the ability to apply conventional experimental methods prior to that date. Those skilled in the art can, under the guidance of this application, improve and implement this solution in combination with their own capabilities. Some typical known structures or methods should not be obstacles for those skilled in the art to implement this application. It should be noted that those skilled in the art can make several modifications and improvements without departing from the structure of the present invention. These should also be considered within the scope of protection of the present invention, and will not affect the effectiveness of the implementation of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.
Claims
1. A method for fabricating a digital guide plate for jaw function-oriented placement of bone cement, characterized in that, Including the following steps: S1. Data acquisition: Images of the mandibular bone defect area of the patient are acquired through maxillofacial CT scan to obtain raw DICOM data of maxillofacial CT. S2. Model reconstruction: Threshold segmentation and three-dimensional reconstruction are performed on the original DICOM data of the maxillofacial CT to obtain a three-dimensional digital model of the mandible. S3. Defect calibration: Based on the cause of the defect, perform corresponding preprocessing on the three-dimensional digital model of the mandible and extract the full-dimensional feature parameters of the defect area. S4. Positioning deviation control: The three-dimensional digital model of the mandible and the full-dimensional feature parameters of the defect area are processed by the unified benchmark positioning rules. The same set of fixing holes penetrating the mandible are generated on the osteotomy guide plate, the gap maintenance guide plate, and the bone cement interposition shaping guide plate to obtain the basic model of the first phase of the collaborative guide plate group. S5. Functional space reservation: Guided by jaw function reconstruction, the parameters of the basic model of the first-phase collaborative guide plate group are optimized, and the molding cavity height of the bone cement interposition shaping guide plate is adjusted to obtain the final digital model of the first-phase collaborative guide plate group. S6. Quantitative filling control: Using the original DICOM data of the maxillofacial CT collected twice after the first-stage surgery, a three-dimensional digital model of the hardened bone cement interstitial placement is reconstructed. Based on this model, a three-sided closed and one-sided open cancellous bone quantitative filling guide is designed to ensure that the inner cavity of the cancellous bone quantitative filling guide is completely matched with the shape of the bone cement interstitial placement, thus obtaining the digital model of the second-stage filling guide. S7. Guide plate preparation: The final digital model of the first-phase synergistic guide plate group and the digital model of the second-phase filling guide plate are processed into physical objects using additive manufacturing technology to obtain the physical objects of the first-phase synergistic guide plate group and the physical objects of the quantitative filling guide plate for cancellous bone.
2. The method for fabricating a digital guide plate for jaw function-guided placement between bone cements according to claim 1, characterized in that, In step S1, the maxillofacial CT scan simultaneously acquires images of the patient's corresponding dentition and opposing dentition, and the original DICOM data of the maxillofacial CT includes information on dentition and occlusal relationship.
3. The method for fabricating a digital guide plate for jaw function-guided placement between bone cements according to claim 2, characterized in that, In step S2, the original DICOM data of the maxillofacial CT is imported into computer-aided design software, and after threshold segmentation and three-dimensional fitting, a quantifiable three-dimensional digital model of the mandible is obtained.
4. The method for fabricating a digital guide plate for jaw function-guided placement between bone cements according to claim 3, characterized in that, In step S3, the corresponding preprocessing is as follows: for tumor or infectious defects, osteotomy boundary marking is completed, and for traumatic fracture defects, fracture reduction simulation is completed.
5. The method for fabricating a digital guide plate for jaw function-guided placement between bone cements according to claim 4, characterized in that, In step S4, the osteotomy guide plate is an arc-shaped plate structure that conforms to the surface of the mandible, and the same set of fixation holes penetrating the mandible are evenly distributed on the osteotomy guide plate body.
6. The method for fabricating a digital guide plate for jaw function-guided placement between bone cements according to claim 5, characterized in that, In step S4, the gap maintaining guide plate has a frame-shaped structure, its inner contour matches the boundary of the defect area, and it shares the same set of fixation holes with the osteotomy guide plate.
7. The method for fabricating a digital guide plate for jaw function-guided placement between bone cements according to claim 6, characterized in that, In step S5, the bone cement interstitial placement shaping guide plate is provided with a groove-shaped molding cavity, the contour of which is adapted to the shape of the defect area.
8. The method for fabricating a digital guide plate for jaw function-guided placement between bone cements according to claim 7, characterized in that, In step S6, the cancellous bone quantitative filling guide plate is a groove-shaped structure with three closed sides and one open side, and its inner cavity contour is completely matched with the shape of the hardened bone cement interposition material.
9. The method for fabricating a digital guide plate for jaw function-guided placement between bone cements according to claim 8, characterized in that, In step S7, the first-phase collaborative guide plate group includes an osteotomy guide plate, a gap maintenance guide plate, and a bone cement interposition shaping guide plate. The structure of each guide plate entity is completely consistent with the corresponding digital model.
10. A digital guide plate for jaw function-guided placement of intracranial implants, characterized in that, This includes a phase I synergistic guide plate assembly and a quantitative filler guide plate for cancellous bone. The first-phase collaborative guide plate assembly consists of an osteotomy guide plate, a gap maintenance guide plate, and a bone cement interposition shaping guide plate. The osteotomy guide plate, gap maintenance guide plate, and bone cement interposition shaping guide plate have the same set of aligned fixing holes that penetrate the mandible, forming a common positioning structure for interchangeable assembly. The osteotomy guide plate is an arc-shaped plate structure that conforms to the surface of the mandible. The gap maintenance guide plate adopts a frame-shaped enclosure structure and forms a nested limiting fit with the outer contour of the defect area. The bone cement interposition shaping guide plate has a groove-shaped molding cavity that is aligned and adapted to the shape of the defect area. The quantitative filling guide plate for cancellous bone is a U-shaped groove structure with three closed sides and one open side. The inner wall of the quantitative filling guide plate for cancellous bone forms a fully enclosed and limiting fit with the shape of the material placed between the hardened bone cement.