A surgical planning, guide design and robotic system for maxillary endosseous distractor implantation

Abstract

The application relates to a surgical planning, guide plate design and robot system for maxillary endosseous distractor implantation, comprising: a data acquisition module for acquiring multi-modal image data of a patient's craniofacial region and constructing a digital twin three-dimensional head model containing hard tissue, soft tissue and spatial posture; a virtual planning module for generating a personalized surgical plan of the patient on the basis of the digital twin three-dimensional head model; a guide plate design module for designing and manufacturing a personalized surgical guide plate suitable for the patient according to the personalized surgical plan; and a surgical robot execution module for verifying the deviation between the actual pose and the planned pose of the guide plate through an optical navigation system, locking the surgical guide plate when the deviation is less than a preset threshold, and completing osteotomy, drilling and distractor implantation operations according to the personalized surgical plan and the personalized surgical guide plate.

Description

Technical Field

[0001] This invention relates to a surgical navigation system, and more specifically to a surgical planning, guide plate design, and robotic system for implantation of an intraoral retractor in the maxilla. Background Technology

[0002] The maxillary internal traction device is an advanced technology developed for maxillofacial deformities such as maxillary hypoplasia. Its core principle is to use distraction osteogenesis (DO) to stimulate new bone formation in a gradual and minimally invasive manner, thereby achieving the forward movement and morphological reconstruction of the maxilla.

[0003] Unlike traditional orthognathic surgery, which involves a single osteotomy and forward movement, the built-in traction device works through the following technical pathways: Osteotomy and implantation: A precise osteotomy is performed at a predetermined location in the maxilla, and a miniature traction device is implanted. The device is completely embedded in the tissue and is not exposed.

[0004] Incubation period: Wait 5-7 days after surgery to allow the bone fragments to heal initially and prepare for traction.

[0005] Traction period: The traction device is slowly activated daily as prescribed by the doctor (usually 0.5-1.0 mm / day). Under continuous tension, the sutures induce new bone formation, thereby achieving bone lengthening.

[0006] Consolidation period: After traction is completed, maintain for 6-12 weeks until the newly formed bone is fully mineralized and stable, and then perform a second-stage surgery to remove the device.

[0007] This technology overcomes the limitations of traditional one-time retraction methods, and is particularly suitable for complex cases involving severe maxillary hypoplasia, secondary deformities due to cleft lip and palate, and restricted growth and development. China has been conducting research on this technology since 1997 and is now among the world's leaders in terms of disease coverage, number of cases, and complication control. This built-in traction device is more discreet than external mask-type traction devices, reducing psychological burden, and allows for more precise control of the traction direction and force.

[0008] However, the main technical challenges of maxillary internal retractors during surgery include difficulty in controlling the traction direction, high precision requirements for retractor placement, complex osteotomy procedures, and potential damage to the tooth germ or tooth root.

[0009] Traction direction is difficult to control: The built-in traction device cannot flexibly adjust its direction during traction, which may cause the bone movement to deviate from the expected trajectory and affect the treatment effect.

[0010] High precision is required for placement: the fixed arm of the traction device must be precisely placed in areas with thicker bone (such as the zygomatic maxillary junction) and damage to adjacent tooth germs or roots must be avoided. This places extremely high demands on preoperative design and intraoperative operation.

[0011] Osteotomy is a complex procedure: the surgery often requires LeFort type I, II or III osteotomy, which requires complete separation of bone connection but preservation of soft tissue attachment. If incomplete osteotomy occurs during the operation, it will lead to increased traction resistance or even failure.

[0012] Potential nerve and tissue damage: When performing osteotomy, it is necessary to avoid the infraorbital neurovascular bundle and permanent tooth germ, especially in patients during the mixed dentition period, where the risk is even higher. Slight carelessness can lead to sensory abnormalities or tooth development disorders.

[0013] Device-related complications: Improper placement of the traction device may cause loosening of the fixation pins, infection, or exposure of the traction rod, increasing the difficulty of postoperative management.

[0014] Currently, most surgeons place maxillary internal retractors manually, relying mainly on the surgeon's experience and anatomical landmarks for precise placement without robotic assistance. The core of this method lies in the accurate identification and control of key bony structures. This approach requires a high degree of anatomical familiarity and operational stability from the surgeon, has relatively low precision, and requires closer monitoring of the traction process postoperatively.

[0015] Manual placement of an internal maxillary retractor, in the absence of digital navigation assistance, relies primarily on the surgeon's experience, resulting in numerous technical and safety drawbacks. These drawbacks include: Difficulty in controlling traction direction: Due to the lack of preoperative virtual simulation and guide plate guidance, the placement of the traction device is easily affected by subjective judgment, which may cause the traction vector to deviate from the ideal path, potentially resulting in maxillary deviation, movement or rotation, affecting facial symmetry and occlusal reconstruction.

[0016] Precision placement is difficult to guarantee: The implantation positions of the anterior and posterior fixation wings must be strictly matched with the bony anchorage area (such as the zygomatic alveolar ridge and alveolar ridge crest). Manual operation is prone to loosening of the fixation pins or poor osseointegration due to anatomical variations or limited field of vision, which increases the risk of device dislodgement.

[0017] Incomplete osteotomy or excessive damage: Basic separation of the bone is a prerequisite for successful traction, but if the bone suture is not completely split during freehand osteotomy, it will cause increased traction resistance or even failure; conversely, if the operation is too deep, it may damage the nasal mucosa, infraorbital nerve or tooth root structure, causing sensory abnormalities or tooth necrosis.

[0018] High error rate in anatomical structure identification: Especially in complex cases such as secondary deformities of cleft lip and palate, normal anatomical landmarks are often distorted, making manual localization prone to misjudgment and increasing the risk of damage to permanent tooth germs, maxillary sinuses or blood vessels.

[0019] Increased incidence of postoperative complications: Due to initial instability, problems such as fixation nail infection, loosening, and traction rod exposure are more likely to occur during traction, requiring frequent adjustments or early termination of treatment, thus prolonging the overall treatment course. Summary of the Invention

[0020] In view of this, the present invention provides a robot-assisted surgical system for implantation of an intraoral retractor, comprising: The data acquisition module is used to acquire multimodal image data of the patient's craniofacial region, and to register and fuse the multimodal image data to construct a three-dimensional head model containing hard tissue, soft tissue and spatial posture information. The three-dimensional head model serves as a reference model for virtual-real mapping between the patient's anatomical structure and the intraoperative physical space. The virtual planning module performs osteotomy planning, bone segment movement analysis, traction path planning, and traction device implantation pose planning based on the three-dimensional head model, generating personalized surgical plans to achieve data-driven transformation of patient anatomical information into surgical decision information; A surgical guide design module is used to design a personalized surgical guide according to the personalized surgical plan. The personalized surgical guide has a positioning surface that conforms to the target bone surface and a guiding structure for constraining the movement of osteotomy instruments and / or drilling instruments. The personalized surgical guide serves as the physical medium for rigidly transmitting the virtual planning results to the intraoperative physical operations. The surgical robot execution module includes a surgical robot and an optical navigation system. The surgical robot execution module is used to register the spatial coordinate system of the personalized surgical plan with the patient's physical space, guide the personalized surgical guide to be positioned on the target bone surface, verify the deviation between the actual position and the planned position of the guide, and perform or assist in performing osteotomy, drilling and traction device implantation operations according to the personalized surgical plan and the personalized surgical guide after the deviation meets the preset requirements, so as to form an intraoperative closed-loop control integrating planning, execution and verification.

[0021] According to one aspect of the present invention, the data acquisition module includes: Cone-beam computed tomography (CBCT) equipment is used to acquire sub-millimeter resolution images of craniofacial bone tissue and segment and identify the maxillary contour, tooth roots, infraorbital canal (mainly referring to tooth roots, infraorbital nerve and other adjacent important neurovascular structures) and maxillary sinus boundaries. Intraoral scanners or facial 3D scanners are used to acquire data on the dental surface and facial soft tissues; The natural head position recording unit records the patient's natural head position data through three-dimensional photography or gyroscope equipment, which serves as a standardized reference coordinate system for subsequent three-dimensional measurement and surgical design. The data fusion unit is used to spatially register and fuse the bone tissue images, dental surface data, facial soft tissue surface data and natural head position data to establish the three-dimensional head model under a unified reference coordinate system. The natural head position data is used to provide a standardized posture reference for three-dimensional measurement, preoperative planning and intraoperative positioning, so as to eliminate the registration error caused by changes in head position and ensure the geometric fidelity of virtual-real mapping.

[0022] According to one aspect of the invention, the virtual planning module is configured to: Simulate LeFort type I, II or III osteotomy lines and perform bone segment separation simulation on the three-dimensional head model; A traction vector is set, which includes traction direction, traction speed and traction cycle, and the bone segment movement path is dynamically simulated based on the traction vector; Analyze the bone volume conditions of the zygomatic alveolar ridge, alveolar ridge crest and / or other bony anchorage areas to determine the planned implantation position of the traction device fixation unit; Assessment of the maxillary-mandibular relationship after traction, combined with occlusal relationship reconstruction; and Postoperative facial contour changes are output based on a soft tissue prediction model. The virtual planning module uses dynamic simulation to quantify and predict risks related to osteotomy safety, traction stability, and postoperative morphological coordination before surgery.

[0023] According to one aspect of the invention, the guide plate design module is configured to design an integrated guide plate for osteotomy and traction device positioning, the integrated guide plate comprising: The contact surface that fits against the bone surface of the osteotomy area; Osteotomy guide grooves used to limit the movement trajectory of osteotomy instruments; and At least one guide hole for defining the fixed position of the traction device and / or the drilling direction; The geometric parameters and relative spatial positions of the osteotomy guide groove and the at least one guide hole are preferably uniquely determined by the osteotomy line trajectory, fixation point coordinates and implantation angle in the personalized surgical plan, so that the integrated guide plate becomes a rigid physical expression of the virtual planning result, thereby realizing the lossless precision transfer from virtual planning to physical operation.

[0024] According to one aspect of the present invention, the surgical robot execution module is configured to track the spatial positions of the guide plate, instruments and patient reference markers in real time through the navigation system, and to perform position verification and trajectory constraints on the guide plate placement, osteotomy execution and traction device implantation process based on the registration results of the preoperative three-dimensional head model and the intraoperative physical space. The surgical robot execution module uses the planning data in the personalized surgical plan as the driving command and the real-time position feedback from the navigation system as the closed-loop feedback quantity to form an intraoperative closed-loop control process of planning-execution-measurement-correction.

[0025] According to one aspect of the present invention, the surgical robot execution module adopts a control mode that integrates position feedback and contact force feedback, comprising: The navigation system monitors the position and orientation of the robotic arm's end effector and surgical instruments in real time to ensure that the surgical instruments move along a preset trajectory corresponding to the guide structure; and The force sensor installed at the end of the robotic arm and / or on the surgical instrument monitors the changes in contact force between the instrument and bone tissue. When a change in resistance exceeding the preset range is detected, the robotic arm is controlled to decelerate, stop, or issue an early warning. The position feedback is used to ensure the geometric accuracy of the osteotomy line and screw socket position, and the contact force feedback is used to sense changes in bone tissue density and instrument penetration status. The two are combined to form an active safety protection mechanism against the risk of damage to nerves, tooth roots and thin bone areas.

[0026] According to one aspect of the present invention, the surgical robot execution module supports at least one of the following operating modes: In automatic execution mode, the control system plans the movement path of the robotic arm according to the personalized surgical plan and the guide structure, and autonomously performs osteotomy, drilling and / or traction device implantation under preset constraints. In master-slave teleoperation mode, the operator inputs movement commands via a control handle, and the control system corrects the instrument's movement in real time based on navigation information to confine the instrument's movement within preset safety boundaries; and In the collaborative constraint mode, the surgeon directly operates the surgical instruments by hand, while the robot establishes virtual constraint boundaries corresponding to the planned osteotomy line, drilling depth, or safety boundary through a force feedback system. When the instrument tends to go beyond the planned area, the movement trend is suppressed through force feedback.

[0027] According to one aspect of the present invention, the surgical robot execution module further includes an intraoperative real-time verification submodule, the intraoperative real-time verification submodule being configured to: After osteotomy and / or drilling are completed, the actual osteotomy line spatial trajectory and / or actual pinhole pose are measured using the navigation system. The measurement results are automatically compared with the planned osteotomy line and / or planned implantation pose in the personalized surgical plan to generate quantitative deviation data; and When the deviation data exceeds a preset threshold, a correction prompt is output, the guide plate is repositioned, and / or the replanning process is invoked. The intraoperative real-time verification submodule uses the measured data from the navigation system to complete the quantitative assessment of the operation quality and deviation correction decision before the operation is completed. Attached Figure Description

[0028] The accompanying drawings, which illustrate various embodiments of the present invention, are described below. In the drawings, the same reference numerals denote the same parts. The drawings are not necessarily drawn to scale, and some parts may be enlarged to show the details of the present invention.

[0029] Figure 1 This is a schematic diagram of the surgical planning, guide plate design and robotic system for implantation of an internal maxillary retractor according to the present invention. Figure 2 and Figure 3 These are schematic diagrams of the frontal and lateral three-dimensional reconstructions of the patient's skull before surgery, which are digital twin three-dimensional head models generated by the data acquisition module of the system of this invention; Figure 4 and Figure 5 These are frontal and side views of the patient's skull after surgery using the system of this invention, demonstrating the bony positional relationship after successful anterior displacement of the maxillary segment and the correction effect of midface depression; Figure 6 and Figure 7 This is a schematic diagram of the maxilla of a patient after osteotomy using the system of the present invention, in which the osteotomy line can be seen; Figure 8 This is a schematic diagram of a three-dimensional model of the maxilla, showing the relationship between the osteotomy line and the tooth root; Figure 9 and Figure 10 The installation relationship between the traction device and the osteotomy segment is shown when performing surgery using the system of the present invention; Figure 11 and Figure 12 The relationship between the personalized surgical guide and the traction device is shown when performing surgery using the system of the present invention. Detailed Implementation

[0030] The embodiments of this application will be further described in detail below with reference to the accompanying drawings and examples. The detailed description of the following embodiments and the accompanying drawings are used to illustrate the principles of this application by way of example, but should not be used to limit the scope of this application. This application can be implemented in many different forms and is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

[0031] These embodiments are provided to make the application thorough and complete, and to fully express the scope of the application to those skilled in the art. It should be noted that, unless otherwise specifically stated, the relative arrangement of components and steps, material composition, numerical expressions, and values ​​illustrated in these embodiments should be interpreted as merely exemplary and not as limiting.

[0032] This invention provides a robot-assisted surgical system for implanting a maxillary internal retractor, comprising: A multimodal data fusion and planning subsystem is used to generate three-dimensional surgical plans that include anatomical structures and planning paths; A personalized surgical guide, which has a positioning surface and guiding structure that conforms to the target bone surface, is used to rigidly transfer the spatial planning information in the three-dimensional surgical plan to the intraoperative operating space in the form of physical constraints; An intraoperative robot navigation and closed-loop verification subsystem is used to acquire the actual pose of the guide plate or instrument in real time through optical navigation after the guide plate is positioned, compare it with the planned pose, unlock and execute the operation only when the deviation meets a preset threshold, and verify the operation result again after the key steps are executed.

[0033] The present invention establishes a cyber-physical fusion mechanism based on a single coordinate reference. During the implantation of a maxillary internal retractor, preoperative planning typically exists in a virtual space corresponding to the patient's imaging data, while intraoperative guide plate installation, osteotomy, drilling, and retractor fixation occur in the patient's actual anatomical space. Furthermore, the surgical robot and navigation system each have their own equipment spatial reference. If a unified mapping relationship is lacking between these different spaces, preoperative planning information cannot be accurately transmitted to the intraoperative execution process, and errors are prone to accumulate due to multiple coordinate transformations, manual interpretation, and manual positioning.

[0034] Based on this, the present invention unifies the image space, patient space, and robot space under the same coordinate reference through a data acquisition module, registration process, and navigation measurement process. Specifically, the osteotomy line, drilling path, traction device implantation pose, and traction direction generated by the virtual planning module are first defined in the image space corresponding to the preoperative 3D head model. During the operation, the registration relationship between the patient's actual space and the image space is established through an optical navigation system, and a mapping relationship between the robot execution space and the patient's actual space is further established, so that the various planning parameters defined before the operation can be accurately converted into executable spatial position, direction, and path information during the operation. As a result, key operations such as osteotomy, drilling, and traction device implantation are all performed around a unified spatial reference, reducing the cumulative errors caused by inconsistencies in spatial transformation and deviations in human spatial imagination.

[0035] The invention also features a dual-link collaborative structure that integrates a digital-to-mechanical rigidity transmission mechanism and an error feedback mechanism. First, at the forward transmission level, the virtual planning module transforms the patient's individualized anatomical information into digital surgical decision information such as osteotomy paths, drilling locations, and traction device installation positions. The guide plate design module then generates a personalized surgical guide plate with positioning and fitting surfaces, osteotomy guide grooves, and drilling guide holes based on the aforementioned digital results. Thus, the planning results, originally existing in virtual space, are transformed into physical geometric constraints that can directly influence instrument movement. In other words, the guide plate does not merely serve as a prompt or reference; rather, through its morphological fit with the target bone and / or tooth surfaces and the directional constraints of the guiding structure, it transforms digital instructions on how to operate into mechanical execution conditions with rigid constraints.

[0036] In this forward transmission chain, the guide plate positioning and fitting surface serves to achieve optimal and unique corresponding or highly stable positioning of the guide plate on the patient's anatomical structure, thereby reducing the degree of freedom in guide plate installation; the osteotomy guide groove serves to limit the movement trajectory, direction, and operational boundaries of the osteotomy instruments; and the drilling guide hole serves to limit the entry point, axial direction, and relative positional relationship of the drilling instruments. Therefore, the virtual planning result is not manually reproduced based on the surgeon's subjective understanding, but is directly transmitted to the actual operation stage through the physical constraints of the guide plate structure, thus achieving a high-fidelity mapping from digital scheme to mechanical operation.

[0037] Secondly, at the reverse verification level, this invention utilizes an optical navigation system and an intraoperative real-time verification submodule to construct a measurement-planning error feedback chain. Specifically, after the guide plate is installed, after osteotomy is completed, and / or after drilling is completed, the navigation system can measure the actual pose of the guide plate, the actual spatial trajectory of the osteotomy line, and the actual pose of the screw socket, and automatically compare the above measurement results with the planned pose, planned osteotomy line, and planned hole position in the personalized surgical plan, thereby generating quantitative deviation data such as translational deviation, rotational deviation, trajectory deviation, and positional deviation.

[0038] Based on the quantified deviation data, the system can further determine whether the current operation meets the preset accuracy requirements. When the deviation is within the allowable range, the system allows the next surgical step to proceed; when the deviation exceeds the preset threshold, the system outputs a correction prompt and may trigger repositioning of the guide plate, re-registration of the relationship between the patient space and the image space, or replanning of the local operation path. Therefore, this invention not only guides doctors to perform the procedure according to the plan but also enables quantitative intraoperative judgment of whether the procedure has been performed correctly, giving key surgical steps real-time measurability, comparability, verifiability, and correctability.

[0039] From a system control perspective, this invention essentially transforms the traditional open-loop surgical model into a closed-loop control model. In traditional surgery, there is typically a lack of continuous feedback mechanisms between preoperative planning, intraoperative execution, and postoperative outcomes. Surgeons rely primarily on experience, field of vision, and tactile feedback to complete key positioning and operations. Even minor deviations during surgery are often difficult to identify and quantify in a timely manner, thus representing a typical open-loop operation. In contrast, this invention introduces an optical navigation system as a high-precision intraoperative pose sensor into the surgical process, enabling real-time measurement and quantification of the actual spatial states of the patient, guide plate, robot end effector, and instrument tip.

[0040] Building upon this foundation, the surgeon's role in the system of this invention is no longer merely to rely on experience to directly complete all spatial judgments and action outputs, but rather to assume more responsibilities in planning confirmation, process monitoring, anomaly handling, and final decision-making. The system, in turn, provides unified coordinate mapping, rigid path constraints, intraoperative pose measurement, deviation quantification analysis, and correction prompts. Through this negative feedback mechanism, the surgical process is transformed from a unidirectional flow of direct execution after planning into a closed-loop flow of planning-execution-measurement-comparison-correction, fundamentally improving the control accuracy and repeatability of osteotomy location, drilling location, and traction device implantation pose.

[0041] All terms used in this application have the same meaning as understood by one of ordinary skill in the art to which this application pertains, unless otherwise specifically defined. It should also be understood that terms defined in general dictionaries should be interpreted as having meanings consistent with their meanings in the context of the relevant art, and not as idealized or highly formalized, unless expressly defined herein.

[0042] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, they should be considered part of the specification.

[0043] like Figure 1 As shown, the system of the present invention mainly includes four modules: a data acquisition module, a virtual planning module, a guide plate design module, and a surgical robot execution module, wherein: The data acquisition module is used to acquire multimodal image data of the patient's craniofacial region, and to register and fuse the multimodal image data to construct a three-dimensional head model containing hard tissue, soft tissue, and spatial posture information. This three-dimensional head model serves as a reference model for virtual-real mapping between the patient's anatomical structure and the intraoperative physical space. In one specific embodiment, the data acquisition module includes a cone-beam CT device, an intraoral scanner or a facial 3D scanner, a natural head position recording unit, and a data fusion unit. The cone-beam CT device is used to scan the patient's head, acquiring sub-millimeter resolution images of craniofacial bone tissue. Then, image segmentation algorithms (such as threshold-based region growing or deep learning segmentation networks) are used to automatically or semi-automatically segment the sub-millimeter level jawbone contour, tooth roots, infraorbital canal (mainly referring to tooth roots, infraorbital nerves, and other adjacent important neurovascular structures), and maxillary sinus boundaries from the CT images. The segmented three-dimensional bone model is exported for subsequent virtual planning. Cone-beam CT technology supports multiplanar reconstruction (MPR) and three-dimensional volume rendering, enabling accurate assessment of bone volume, traction anchorage thickness, and osteotomy feasibility. An intraoral scanner or facial 3D scanner acquires dental surface and facial soft tissue data, including the patient's facial data and surface data of the upper and lower dentition and gingiva. A natural head position recording unit records the patient's natural head position data using 3D photography or a gyroscope, serving as a standardized reference coordinate system for subsequent 3D measurements and surgical planning. A data fusion unit spatially registers and fuses bone tissue images, dental surface data, facial soft tissue surface data, and natural head position data to establish a 3D head model under a unified reference coordinate system—a digital twin 3D head model. This model includes high-precision bone, tooth roots, nerve canals, dentition, facial skin, and accurate spatial orientation. Here, the natural head position data provides a standardized posture benchmark for 3D measurements, preoperative planning, and intraoperative positioning, eliminating registration errors introduced by head position changes and ensuring geometric fidelity of the virtual-to-real mapping. Figure 2 and Figure 3 A schematic diagram of a patient's skull (3D head model) before surgery using the system of this invention is shown. Generated by a data acquisition module, the 3D head model clearly displays the skeletal morphology, tooth root positions, and maxillary sinus boundaries, providing a reliable digital foundation for subsequent planning. This 3D head model is then transmitted to a virtual planning module.

[0044] The virtual planning module, based on the 3D head model, performs osteotomy planning, bone segment movement analysis, traction path planning, and traction device implantation posture planning to generate personalized surgical plans, thereby achieving data-driven transformation of patient anatomical information into surgical decision information. The virtual planning module can dynamically assess whether tooth germ damage, nerve compression, or malocclusion occurs during traction. Especially for complex cases such as secondary deformities following cleft lip and palate, it can achieve individualized design for asymmetric correction.

[0045] In a preferred embodiment, the physician uses 3D surgical planning software to perform the following operations: Virtual osteotomy: Based on the patient's condition, LeFort I, LeFort II, or LeFort III osteotomy lines are planned on a 3D head model, and bone segment separation is simulated. Using software for virtual osteotomy, the dentist can manually draw the osteotomy lines or automatically generate recommended osteotomy lines by setting a safe distance from the tooth root apex.

[0046] Traction Vector Setting: Set the traction direction, traction speed, and traction cycle in the software. Activate the dynamic simulation function; the software will demonstrate the daily forward movement of the bone segment in animation, assessing for rotation, deviation, or abnormal soft tissue tension. If the results are not as expected, the system will prompt the doctor to adjust the vector.

[0047] Anchorage zone assessment and fixation pose planning: The software automatically measures the bone thickness and bone density of areas such as the zygomatic alveolar ridge and alveolar ridge crest to find and assess suitable anchorage zones. Based on the size of the pre-selected traction device, the software plans the implantation pose of the two fixation wings of the traction device, including the three-dimensional coordinates of the implantation point and the implantation angle.

[0048] Occlusal Relationship Reconstruction: This is used to assess the relationship between the maxilla and mandible after traction by combining occlusal relationship reconstruction. Specifically, digital models of the maxilla and mandible are imported into electronic jaw simulation software. The simulation simulates the occlusal contact relationship between the maxillary segment and the mandible in the new position after traction, automatically detects early contact points and interference points, and allows for fine-tuning of the traction vector to optimize occlusion.

[0049] Soft tissue prediction: After inputting the position of the bone segment after repositioning, the system calculates the deformation of the facial soft tissues and generates pre- and post-operative comparison images. Doctors can visually assess the improvement in facial shape and, if necessary, modify the osteotomy or traction plan.

[0050] The virtual planning module uses dynamic simulation to quantify and predict risks related to osteotomy safety, traction stability, and postoperative morphological coordination before surgery.

[0051] The surgical guide design module designs a personalized surgical guide based on the personalized surgical plan. This personalized surgical guide has a positioning surface that conforms to the target bone surface and a guiding structure for constraining the movement of osteotomy instruments and / or drilling instruments. The personalized surgical guide serves as the physical medium for rigidly transmitting the virtual planning results to the actual intraoperative manipulation. In this invention, the lower surface of the guide conforms to the target bone surface, thereby forcibly standardizing the operational path to avoid positioning deviations caused by limited field of vision or anatomical variations during freehand placement. Furthermore, the guide has a guiding structure that simultaneously constrains both osteotomy instruments and drilling instruments; the geometric parameters of the guiding structure are determined by the personalized surgical plan.

[0052] The design and manufacturing steps of a personalized surgical guide can be as follows: In virtual planning software, the bone surfaces of the osteotomy and anchorage regions are extracted from a 3D head model; the main body of the guide is formed using reverse engineering software. Positioning ears or keyholes are added to the edge of the guide for temporary intraoperative fixation. Design elements of the guide may include osteotomy guide grooves and drilling guide holes. The osteotomy guide groove is a groove formed on the guide along the virtual osteotomy line, with the center line of the groove essentially coinciding with the planned osteotomy line. The direction of the groove is perpendicular to the bone surface, allowing the blade of an ultrasonic osteotome or oscillating saw to be inserted and move along the groove. The drilling guide hole is a circular guide hole designed at the corresponding position on the guide for the screw hole location of each fixation wing. Preferably, embodiments of the present invention employ an integrated osteotomy and traction device positioning guide, i.e., the same guide simultaneously includes a contact surface that conforms to the bone surface of the osteotomy region, an osteotomy guide groove for defining the movement trajectory of the osteotomy instrument, and multiple guide holes for traction device positioning. The integrated surgical guide is temporarily fixed to the maxilla by at least two bone screws to ensure it does not shift during osteotomy and drilling (generally, the guide can be positioned with robot assistance first, and then temporarily fixed by bone screws / locking mechanisms, where the locking mechanism can be a robot end effector clamping and locking, while actual fixation to the bone surface is preferably achieved by bone screws); the designed guide model is exported and 3D printed. The geometric parameters and relative spatial positions of the osteotomy guide groove and guide hole are uniquely determined by the osteotomy line trajectory, fixation point coordinates, and implantation angle in the personalized surgical plan, so that the integrated guide becomes a rigid physical representation of the virtual planning result, thereby achieving non-destructive precision transfer from virtual planning to physical operation. In some embodiments, an occlusal guide can be designed separately.

[0053] The surgical robot execution module includes a surgical robot and an optical navigation system. The module is configured to track the spatial positions of the surgical guide, instruments, and patient reference landmarks in real time via the optical navigation system. Based on the registration results between the preoperative 3D head model and the intraoperative physical space, it performs position verification and trajectory constraints on the placement of the surgical guide, osteotomy, and traction device implantation. The module registers the spatial coordinate system of the personalized surgical plan with the patient's physical space and guides or controls the surgical robot to hold and place the personalized surgical guide on the bone surface. The optical navigation system verifies the deviation between the actual and planned poses of the surgical guide. When the deviation is less than a preset threshold, the surgical guide is locked, and osteotomy, drilling, and traction device implantation are performed according to the personalized surgical plan and the surgical guide. Here, the robot control workstation automatically calculates the optimal path for the robotic arm end effector to grip the guide plate, avoiding collisions with soft tissue. A guide plate gripper is installed at the end effector to hold the personalized guide plate. The robotic arm is moved near the target area, and then an automatic alignment mode is activated. The optical navigation system measures the guide plate's pose in real time, comparing the actual pose with the planned pose to calculate the deviation (positional and angular deviations). If the deviation is less than a preset threshold, the control system issues a command, and a pneumatic or electromagnetic locking device temporarily fixes the guide plate to the bone surface (generally, the guide plate can be first positioned with robot assistance, and then temporarily fixed by a bone screw / locking mechanism; the locking mechanism can be a robot end effector gripper, while actual fixation to the bone surface is preferably achieved by a bone screw). If the deviation exceeds the limit, the system will prompt the surgeon to adjust or re-register. Overall, the surgical robot execution module uses the planning data in the personalized surgical plan as the driving command and the real-time position feedback from the navigation system as the closed-loop feedback quantity, forming a planning-execution-measurement-correction intraoperative closed-loop control process. The surgical robot autonomously controls the robotic arm to complete guide plate installation, osteotomy, and traction device fixation. The surgical robot execution module can adopt a control mode that integrates position feedback and contact force feedback, including: real-time monitoring of the position and posture of the robotic arm end effector and surgical instruments through an optical navigation system to ensure that the surgical instruments move along a preset trajectory corresponding to the guide structure; and monitoring of the contact force changes between the instruments and bone tissue through force sensors set on the robotic arm end effector and / or surgical instruments, and controlling the robotic arm to decelerate, stop or issue an early warning when a resistance change exceeding a preset range is detected; wherein, position feedback is used to ensure the geometric accuracy of the osteotomy line and screw socket pose, and contact force feedback is used to sense changes in bone tissue density and instrument penetration status, and the two are integrated to form an active safety protection mechanism against the risk of damage to nerves, tooth roots and thin bone areas.

[0054] The surgical robot's execution module supports at least one of the following operating modes: Fully autonomous mode: The control system plans the robotic arm's motion path based on the personalized surgical plan and guide structure, and autonomously performs osteotomy, drilling, and / or traction device implantation operations under preset constraints; Master-slave teleoperation mode: The surgeon inputs motion commands through a control handle, and the control system corrects the instrument's motion in real time based on navigation information to limit the instrument's motion within preset safety boundaries; Collaborative constraint mode: The surgeon directly operates the surgical instruments by hand, and the robot establishes virtual constraint boundaries corresponding to the planned osteotomy line, drilling depth, or safety boundary through a force feedback system. When the instrument tends to exceed the planned area, the force feedback suppresses the movement trend.

[0055] The following reference Figures 4 to 12 This paper describes the overall surgical effects that can be achieved using the system of the present invention.

[0056] Figure 4 and Figure 5 These are frontal and side views of the patient's skull after surgery using the system of this invention, demonstrating the bony positional relationship after successful anterior displacement of the maxillary segment and the correction effect of midface concavity, with a comparison. Figure 2 and Figure 3 As can be seen, using the system of the present invention, the maxillary segment has been successfully moved forward, the midface depression has been corrected, and the occlusal relationship has been restored to normal.

[0057] Figure 6 and Figure 7 This is a schematic diagram of the maxilla of a patient after osteotomy using the system of the present invention, in which the osteotomy line can be clearly seen. The osteotomy line is precisely positioned and has a safe margin from the root apex and the infraorbital nerve.

[0058] Figure 8 This is a 3D model diagram of the patient's maxilla, showing the relationship between the osteotomy line and the tooth root. As can be seen from the diagram, the osteotomy line generated by the planning software of this invention largely avoids the tooth root and its surrounding nerve tissue, meeting clinical safety requirements.

[0059] Figure 9 and Figure 10 The installation relationship between the traction device and the osteotomy segment of the system of the present invention is shown during surgery. Figure 11 and Figure 12The diagram illustrates the relationship between the personalized surgical guide and the retractor during surgery. As seen in these figures, the personalized surgical guide is designed to fit snugly against the patient's maxilla, thus strictly regulating the surgical path and avoiding positioning errors caused by limited field of vision or anatomical variations during freehand placement. The personalized surgical guide features a slender osteotomy guide groove and multiple drilling guide holes. These guide holes determine the position of the retractor's fixation wings. The projected positions of the screw holes for the anterior and posterior fixation wings of the retractor are precisely indicated by these guide holes on the guide. After osteotomy, the surgeon drills directly through the guide, removes the guide, and then installs the retractor. At this point, the retractor screws can accurately enter the pre-drilled holes. This operation avoids the bone segment displacement problems that can occur in traditional surgery where osteotomy is performed first, followed by separate positioning and drilling. It ensures that the screws can firmly fix the retractor without being too close to the osteotomy line, which could lead to bone fracture, while also safely avoiding pre-planned dangerous areas such as tooth roots and nerves.

[0060] In one embodiment, the surgical robot execution module further includes an intraoperative real-time verification submodule. After osteotomy and drilling are completed, the intraoperative real-time verification submodule is configured to measure the actual osteotomy line spatial trajectory and / or actual pinhole pose via a navigation system; automatically compare the measurement results with the planned osteotomy line and / or planned implantation pose in the personalized surgical plan to generate quantitative deviation data; and when the deviation data exceeds a preset threshold, output a correction prompt, trigger a repositioning guide plate, and / or call a replanning process. The intraoperative real-time verification submodule, based on the measured data from the navigation system, completes a quantitative assessment of the operation quality and a deviation correction decision before the surgery is completed.

[0061] In one embodiment, the surgical robot execution module adopts a control mode that integrates force feedback and visual feedback during surgery, including: monitoring the position of the end effector of the robotic arm in real time through the optical navigation system to ensure that it moves along the preset trajectory of the guide structure; monitoring the contact force in real time through sensors on the robotic arm; automatically decelerating or stopping when abnormal resistance changes are detected and providing feedback, thereby avoiding unintentional cutting of non-target tissues and causing damage during surgery.

[0062] The system supports multiple modes. Example 1 below uses a doctor-led navigation-assisted mode, where the robot is primarily used for spatial registration, guide plate positioning assistance, and intraoperative verification. Example 2 below uses a robot cooperative constraint mode or a robot-assisted execution mode, where the robot further participates in the real-time control of the osteotomy and / or drilling process.

[0063] Example 1

[0064] This embodiment provides an application of a robot-assisted surgical system for implanting a maxillary internal retractor during patient surgery. The system includes a data acquisition module, a virtual planning module, a guide plate design module, and a surgical robot execution module. The surgical robot execution module includes at least an optical navigation system and an intraoperative real-time verification submodule. In this embodiment, the robot is mainly used for spatial registration, guide plate positioning assistance, and intraoperative verification, while osteotomy and drilling operations are primarily performed by the surgeon under the guidance of a personalized surgical guide.

[0065] First, the system acquires preoperative craniofacial multimodal imaging data of the patient through a data acquisition module. This multimodal imaging data includes CT or CBCT images for reconstructing the maxilla, alveolar bone, tooth roots, and surrounding bony anatomy; preferably, it also includes intraoral scan data to improve the accuracy of dental surface morphology and occlusal relationships; when necessary, MRI data and / or facial 3D scan data can also be introduced to supplement soft tissue contours and local spatial posture information. The system performs denoising, segmentation, coordinate unification, registration, and fusion processing on the above data to construct a 3D head model containing hard tissue, soft tissue, and spatial posture information.

[0066] Then, the virtual planning module performs personalized surgical planning based on the three-dimensional head model. Specifically, this includes: determining the maxillary osteotomy range and osteotomy line position; analyzing the expected anterior displacement direction and distance of the bone segment; determining the installation position, installation angle, traction direction, and screw hole positions corresponding to the anterior and posterior fixation wings of the traction device; and assessing the safe distance between the osteotomy line and the tooth root, infraorbital nerve, and adjacent dangerous anatomical structures. Figure 8 This shows a three-dimensional model of the patient's maxilla and the positional relationship between the planned osteotomy line and the tooth root. From Figure 8 It is evident that the planned osteotomy line avoids the tooth root and its adjacent nerve tissue, which meets clinical safety requirements.

[0067] After completing the virtual planning, the guide plate design module generates a personalized surgical guide plate based on the individualized surgical plan. The personalized surgical guide plate includes a positioning and fitting surface that closely fits the target bone surface of the patient's maxilla, an osteotomy guide groove for limiting the movement trajectory of the osteotomy instruments, and multiple drilling guide holes for indicating the positions of the traction device fixation screw holes. Figure 11 and Figure 12 The diagram illustrates the positional correspondence between the personalized surgical guide and the traction device during the procedure, where the screw hole positions of the front and rear fixation wings of the traction device are precisely defined by guide holes on the guide plate.

[0068] During the procedure, after exposing the target surgical area, the surgeon installs the personalized surgical guide onto the target bone surface of the patient's maxilla. Because the positioning and fitting surface matches the bone surface topology, the guide achieves stable and preferably uniquely corresponding positioning. At this point, the optical navigation system acquires the correspondence between the patient's reference coordinates, the guide's coordinates, and the planned spatial coordinates, and performs real-time comparison between the guide's actual pose and the planned pose. When the comparison result meets preset translational and rotational deviation thresholds, the system allows the patient to proceed to the next surgical step; when the comparison result exceeds the thresholds, the system prompts for repositioning the guide and / or re-registration.

[0069] Subsequently, the doctor used the osteotomy guide groove on the personalized surgical guide to complete the maxillary osteotomy. Figure 6 and Figure 7 The diagrams show the frontal and side views of the maxilla after osteotomy performed using the system of this invention. Figure 6 and Figure 7 As can be seen, the osteotomy line is precisely positioned and maintains a safe margin between it and the root apex and the infraorbital nerve.

[0070] After the osteotomy is completed, the surgeon continues to pre-drill holes through the guide holes on the personalized surgical guide to form screw holes corresponding to the anterior and posterior fixation wings of the traction device. Because the position and direction of the drill holes are rigidly constrained by the guide plate, positional deviations caused by traditional freehand drilling can be avoided.

[0071] In this embodiment, after osteotomy and / or drilling, the intraoperative real-time verification submodule uses an optical navigation system to measure the actual osteotomy line spatial trajectory and / or actual pinhole pose. The measurement results are then automatically compared with the planned osteotomy line and / or planned implantation pose in the personalized surgical plan to generate quantitative deviation data. When the deviation data exceeds a preset threshold, the system outputs a correction prompt, triggering a repositioning of the guide plate and / or invoking a replanning process. With this intraoperative real-time verification submodule, surgeons can quantitatively assess the quality of the operation before the surgery is completed and make timely deviation corrections.

[0072] After completing the pre-drilling, the personalized surgical guide is removed, and the traction device is installed at the target position on the patient's maxilla. Figure 9 and Figure 10 The installation relationship between the intraoperative traction device and the osteotomy segment is shown. Because the traction device fixation screws can accurately enter the pre-drilled holes, the installation position and posture of the traction device can be highly consistent with the preoperative plan, while avoiding the impact of subsequent fixation accuracy due to bone segment displacement after osteotomy.

[0073] Figure 4 and Figure 5The diagrams show the frontal and side views of the patient's skull after surgery using the system of this invention. Comparison with the preoperative state reveals that the maxillary segment has been successfully moved forward, the midface concavity has been corrected, the bony positional relationship has significantly improved, and the occlusion has returned to normal. This demonstrates that the system of this invention can achieve complete and precise control from preoperative planning to intraoperative execution and postoperative improvement of bone segment position.

[0074] Example 2

[0075] This embodiment also provides an application of a robot-assisted surgical system for implanting a maxillary internal retractor in patient surgery. Unlike Embodiment 1, the surgical robot execution module in this embodiment is not only used for guide plate pose verification and intraoperative quality assessment, but also further adopts a control mode that integrates force feedback and visual feedback to perform real-time motion control and abnormality protection during osteotomy and / or drilling.

[0076] In this embodiment, the data acquisition module, virtual planning module, and guide plate design module can operate in a manner basically the same as in Embodiment 1. That is, a three-dimensional head model is constructed using multimodal image data, and personalized planning of osteotomy line, drilling path, traction path, and traction device implantation posture is completed based on the three-dimensional head model. At the same time, a personalized surgical guide plate with positioning and fitting surface, osteotomy guide groove, and drilling guide hole is formed, which will not be described in detail here.

[0077] During the procedure, after the surgeon installs the personalized surgical guide on the target bone surface of the patient's maxilla, the surgical robot's execution module monitors the relative spatial relationship between the robotic arm's end effector, the guide, and the patient's reference coordinates in real time through an optical navigation system. This ensures that the instruments carried by the robotic arm's end effector are consistent with the pre-planned path and the guide structure.

[0078] During osteotomy, if a robot-assisted osteotomy mode is used, the end effector of the robotic arm carries the osteotomy instrument along the osteotomy guide groove of the personalized surgical guide, or along the target trajectory generated by the virtual planning module. The optical navigation system continuously outputs end effector position data to verify the real-time spatial position of the instrument tip; simultaneously, force sensors located at the end effector or joints of the robotic arm monitor changes in contact force, resistance, vibration characteristics, and / or torque during the osteotomy process in real time. When abnormal resistance changes are detected, such as a sudden increase in resistance, abnormal thinning of local bone, deviation of the instrument from the preset cutting plane, or potential proximity to non-target soft or hard tissue, the system automatically triggers deceleration, pause, or stop control and outputs alarm information to the physician.

[0079] During drilling, if a robot-assisted drilling mode is used, the robotic arm controls the entry point, feed direction, and drilling depth of the drilling instrument according to the planned drilling path, and achieves dual constraints in conjunction with the guide plate guide holes. At this time, visual feedback is used to verify the drill bit's spatial posture in real time, and force feedback is used to monitor changes in drilling resistance. When the system identifies abnormal resistance peaks, abnormal drilling feed, or a deviation from the safe path, it immediately executes limit stops, deceleration, or stops to reduce the risk of damage to the tooth root, nerves, and adjacent thin bone areas.

[0080] After osteotomy and drilling are completed, the intraoperative real-time verification system continues to measure the actual osteotomy line trajectory and actual screw socket position through the navigation system, and automatically compares it with the planning results to generate deviation data. If the deviation meets the requirements, the guide plate can be removed and the traction device can be installed; if the deviation exceeds the preset range, the system prompts the doctor to make corrections, and if necessary, the guide plate can be repositioned or the local operation path can be replanned.

[0081] Subsequently, the doctor installed the traction device according to the pre-drilled hole position. Figure 9 and Figure 10 The positional relationship between the traction device and the osteotomy segment shown is also applicable to this embodiment. Through the coordinated action of pre-drilled holes in the guide plate and robot control, the traction device fixing screws can accurately enter the predetermined position on the target bone surface, thereby ensuring that the traction direction of the traction device is consistent with the preoperative plan.

[0082] After the surgery, the patient's bone improvement can be achieved by... Figure 4 and Figure 5 As shown, the maxillary segment achieves the expected anterior displacement, midfacial concavity is improved, and occlusion is restored to normal. Furthermore, because this embodiment further incorporates force and visual feedback fusion control during the osteotomy and drilling stages, it can further improve intraoperative safety while maintaining planning accuracy, reducing the risk of accidental cutting, accidental drilling, and damage to non-target tissues.

[0083] In summary, Example 2 further enhances the robot execution module's ability to actively control and protect against abnormalities during the surgical procedure, based on Example 1. It is particularly suitable for complex craniofacial cases with limited anatomical space, numerous adjacent dangerous structures, and higher requirements for osteotomy and drilling precision.

[0084] Furthermore, under the force feedback and visual feedback fusion control mode described in Example 2, the closed-loop characteristics of the present invention are further enhanced. The optical navigation system provides visual feedback information on the position and attitude of the instrument's end effector to ensure that the instrument's trajectory is consistent with the planned path and the guide plate structure; the force sensor on the robotic arm provides mechanical feedback information such as contact force, resistance changes, torque changes, and abnormal vibrations to identify whether the instrument has entered non-target tissue, whether abnormal jamming has occurred, or whether it has deviated from the expected cutting state. By fusing visual feedback and force feedback, the system can not only determine where the instrument is located but also what contact state the instrument is in, thereby further improving the ability to identify and actively protect against damage risks to non-target tissues.

[0085] Therefore, from a deeper mechanistic perspective, this invention is not simply a matter of piecing together image planning, guide plate design, robotic execution, and optical navigation. Instead, it establishes a dual-link closed-loop system combining forward rigid transmission and reverse error feedback under a unified spatial reference. This system enables the preoperative digital scheme to act on the intraoperative physical operation process in a verifiable, traceable, and calibrable manner, thereby achieving high precision, high safety, and high repeatability in the osteotomy, drilling, and implantation steps of maxillary internal retractor implantation surgery.

[0086] Based on the above principles, this invention can effectively reduce the uncertainties caused by the surgeon's subjective judgment, spatial conversion errors, limited intraoperative field of vision, and local anatomical variations, and provide a data foundation for postoperative efficacy evaluation, error analysis, and continuous optimization of surgical plans.

[0087] It should also be noted that, for example, multimodal registration can be used, including stepwise registration of CT (hard tissue), MRI (soft tissue), intraoral scan (dental crown), and facial scan (soft tissue contour). One example illustrates this, with a registration error ≤0.5mm (this is just an example). The 3D head model includes tooth roots, crowns, maxillary sinus walls, palatal bone thickness, tooth roots, infraorbital nerve, and other adjacent important neurovascular structures. Furthermore, the traction path planning clearly defines the traction direction vector, osteotomy segment movement stroke, traction device implantation angle window, and avoidance zone constraints (one example being ≥2mm from the root apex and ≥1mm from the nerve canal). This process provides a uniquely corresponding coordinate reference for all subsequent operations. The core of the planning is generating quantitative surgical decision parameters.

[0088] The embodiments of this application have now been described in detail. To avoid obscuring the concept of this application, some details known in the art have not been described. Those skilled in the art can fully understand how to implement the technical solutions disclosed herein based on the above description.

[0089] While specific embodiments of this application have been described in detail by way of examples, those skilled in the art should understand that the above examples are for illustrative purposes only and are not intended to limit the scope of this application. Those skilled in the art should understand that modifications can be made to the above embodiments or equivalent substitutions can be made to some technical features without departing from the scope and spirit of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any manner.

Claims

1. A robot-assisted surgical system for implantation of a maxillary internal retractor, comprising: The data acquisition module is used to acquire multimodal image data of the patient's craniofacial region, and to register and fuse the multimodal image data to construct a three-dimensional head model containing hard tissue, soft tissue and spatial posture information. The three-dimensional head model serves as a reference model for virtual-real mapping between the patient's anatomical structure and the intraoperative physical space. The virtual planning module performs osteotomy planning, bone segment movement analysis, traction path planning, and traction device implantation pose planning based on the three-dimensional head model, generating personalized surgical plans to achieve data-driven transformation of patient anatomical information into surgical decision information; The guide plate design module is used to design a personalized surgical guide plate according to the personalized surgical plan. The personalized surgical guide plate has a positioning surface that fits with the target bone surface and a guiding structure for constraining the movement of osteotomy instruments and / or drilling instruments. The personalized surgical guide plate serves as a physical medium for rigidly transmitting the virtual planning results to the intraoperative physical operation. as well as The surgical robot execution module includes a surgical robot and an optical navigation system. The surgical robot execution module is used to register the spatial coordinate system of the personalized surgical plan with the patient's physical space, guide the personalized surgical guide to be positioned on the target bone surface, verify the deviation between the actual position and the planned position of the guide, and perform or assist in performing osteotomy, drilling and traction device implantation operations according to the personalized surgical plan and the personalized surgical guide after the deviation meets the preset requirements, so as to form an intraoperative closed-loop control integrating planning, execution and verification.

2. The system as claimed in claim 1, wherein, The data acquisition module includes: Cone-beam computed tomography (CBCT) equipment is used to acquire sub-millimeter resolution images of craniofacial bone tissue and segment and identify the maxillary contour, tooth roots, infraorbital canal (mainly referring to tooth roots, infraorbital nerve and other adjacent important neurovascular structures) and maxillary sinus boundaries. Intraoral scanners or facial 3D scanners are used to acquire data on the dental surface and facial soft tissues; The natural head position recording unit records the patient's natural head position data through three-dimensional photography or gyroscope equipment, which serves as a standardized reference coordinate system for subsequent three-dimensional measurement and surgical design. The data fusion unit is used to spatially register and fuse the bone tissue images, dental surface data, facial soft tissue surface data and natural head position data to establish the three-dimensional head model under a unified reference coordinate system. The natural head position data is used to provide a standardized posture reference for three-dimensional measurement, preoperative planning and intraoperative positioning, so as to eliminate the registration error caused by changes in head position and ensure the geometric fidelity of virtual-real mapping.

3. The system as described in claim 1, wherein, The virtual planning module is configured to: Simulate LeFort type I, II or III osteotomy lines and perform bone segment separation simulation on the three-dimensional head model; A traction vector is set, which includes traction direction, traction speed and traction cycle, and the bone segment movement path is dynamically simulated based on the traction vector; Analyze the bone volume conditions of the zygomatic alveolar ridge, alveolar ridge crest and / or other bony anchorage areas to determine the planned implantation position of the traction device fixation unit; Assess the relationship between the mandible and mandible after traction by combining occlusal relationship reconstruction. as well as Postoperative facial contour changes are output based on a soft tissue prediction model. The virtual planning module uses dynamic simulation to quantify and predict risks related to osteotomy safety, traction stability, and postoperative morphological coordination before surgery.

4. The system as described in claim 1, characterized in that, The guide plate design module is configured to design an integrated guide plate for osteotomy and traction device positioning, the integrated guide plate comprising: The contact surface that fits against the bone surface of the osteotomy area; Osteotomy guide grooves used to limit the movement trajectory of osteotomy instruments; and At least one guide hole for defining the fixed position of the traction device and / or the drilling direction; The geometric parameters and relative spatial positions of the osteotomy guide groove and the at least one guide hole are preferably uniquely determined by the osteotomy line trajectory, fixation point coordinates and implantation angle in the personalized surgical plan, so that the integrated guide plate becomes a rigid physical expression of the virtual planning result, thereby realizing the lossless precision transfer from virtual planning to physical operation.

5. The system as described in claim 1, characterized in that, The surgical robot execution module is configured to track the spatial positions of the guide plate, instruments and patient reference markers in real time through the navigation system, and to perform position verification and trajectory constraints on the guide plate placement, osteotomy and traction device implantation process based on the registration results of the preoperative three-dimensional head model and the intraoperative physical space. The surgical robot execution module uses the planning data in the personalized surgical plan as the driving command and the real-time position feedback from the navigation system as the closed-loop feedback quantity to form an intraoperative closed-loop control process of planning-execution-measurement-correction.

6. The system as described in claim 1, characterized in that, The surgical robot execution module adopts a control mode that integrates position feedback and contact force feedback, including: The navigation system monitors the position and orientation of the robotic arm's end effector and surgical instruments in real time to ensure that the surgical instruments move along a preset trajectory corresponding to the guide structure; and The force sensor installed at the end of the robotic arm and / or on the surgical instrument monitors the changes in contact force between the instrument and bone tissue. When a change in resistance exceeding the preset range is detected, the robotic arm is controlled to decelerate, stop, or issue an early warning. The position feedback is used to ensure the geometric accuracy of the osteotomy line and screw socket position, and the contact force feedback is used to sense changes in bone tissue density and instrument penetration status. The two are combined to form an active safety protection mechanism against the risk of damage to nerves, tooth roots and thin bone areas.

7. The system as described in claim 1, characterized in that, The surgical robot execution module supports at least one of the following operating modes: In automatic execution mode, the control system plans the movement path of the robotic arm according to the personalized surgical plan and the guide structure, and autonomously performs osteotomy, drilling and / or traction device implantation under preset constraints. In master-slave teleoperation mode, the operator inputs movement commands via a control handle, and the control system corrects the instrument's movement in real time based on navigation information to confine the instrument's movement within preset safety boundaries; and In the collaborative constraint mode, the surgeon directly operates the surgical instruments by hand, while the robot establishes virtual constraint boundaries corresponding to the planned osteotomy line, drilling depth, or safety boundary through a force feedback system. When the instrument tends to go beyond the planned area, the movement trend is suppressed through force feedback.

8. The system as described in claim 1, characterized in that, The surgical robot execution module further includes an intraoperative real-time verification submodule, which is configured as follows: After osteotomy and / or drilling are completed, the actual osteotomy line spatial trajectory and / or actual pinhole pose are measured using the navigation system. The measurement results are automatically compared with the planned osteotomy line and / or planned implantation pose in the personalized surgical plan to generate quantitative deviation data; as well as When the deviation data exceeds a preset threshold, a correction prompt is output, the guide plate is repositioned, and / or the replanning process is invoked. The intraoperative real-time verification submodule uses the measured data from the navigation system to complete the quantitative assessment of the operation quality and deviation correction decision before the operation is completed.

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