Electronic facebow angle precision testing system using medical jaw frame

Abstract

The present application relates to a kind of electronic face bow angle precision test system using medical jaw frame, comprising: jaw frame, electronic face bow and test terminal;The transmitter of electronic face bow is fixed on the same plane with jaw frame;The receiver of electronic face bow is rigidly connected with the maxillary body of jaw frame by tooling;The host computer of electronic face bow is electrically connected with test terminal;Jaw frame is used to set the set value of test index, and when simulating the forward movement, backward movement, left or right lateral movement of mandible with set value, it drives the receiver to move together;During the movement of simulating mandible, the host computer of electronic face bow measures the pose data of receiver;The test terminal is used to calculate the measured value of test index based on the pose data, and the measured deviation value of measured value and set value;And the measurement deviation value of multiple measurements under different set values is estimated to estimate the measurement precision of electronic face bow.The present application realizes electronic face bow angle precision test, and test process is efficient and reliable.

Description

Technical Field

[0001] This invention belongs to the field of testing technology and oral medical device technology, specifically relating to an electronic facebow angle accuracy testing system using a medical jaw frame. Background Technology

[0002] The electronic facebow is a precise tooth occlusion tracking and positioning device that can record mandibular movement trajectory and describe condylar mutation data. In conjunction with a digital CAD / CAM system, it provides dynamic data for digital treatment processes, effectively reducing clinical jaw adjustment time.

[0003] The electronic face bow consists of three parts: a transmitter and support, a mandibular fork and receiver, and a system host. The transmitter and support are installed on the patient's head and generate a stable magnetic field around the head after power-on. The receiver is installed on the patient's mandible via the mandibular fork to sense the spatial magnetic field. The system host is used for posture calculation and data output. During normal operation, the patient wearing the mandibular fork performs mandibular protrusion, retraction, leftward movement, rightward movement, and wide-opening movement. The receiver senses the magnetic field during the movement, and the system host calculates the movement trajectory, then calculates the angle between the trajectory and a reference plane, and finally outputs this angle for use in dental prosthesis restoration, etc.

[0004] When evaluating the accuracy of angle measurement using electronic face bow equipment, a reference plane is usually manually specified. The angle between the measurement trajectory and the reference plane varies depending on the reference plane. Testers cannot accurately control the position of the reference plane, making it difficult to precisely test the angle measurement accuracy of the electronic face bow in actual operation, thus failing to meet testing requirements. Therefore, existing methods cannot be used to complete the detection and screening of electronic face bow angle tests. Summary of the Invention

[0005] Based on the above analysis, the present invention aims to disclose an electronic facebow angle accuracy testing system using a medical jaw frame, which is used to solve the problem of testing electronic facebow angles.

[0006] This invention discloses an electronic facebow angle accuracy testing system using a medical jaw frame, comprising: a jaw frame, an electronic facebow to be tested, and a testing terminal; The transmitter of the electronic face bow is fixed on the same plane as the jaw frame; the receiver of the electronic face bow is rigidly connected to the maxillary body of the jaw frame through a tooling; the main unit of the electronic face bow is electrically connected to the test terminal. The jaw frame is used to set the preset values ​​of the test indicators, and when simulating the forward, backward, left or right movement of the mandible at the preset values, it drives the receiver to move together; During the simulated mandibular movement, the main unit of the electronic facebow measures the pose data of the receiver; The test terminal is used to calculate the measured value of the test index and the measurement deviation value between the measured value and the set value based on the pose data; and to obtain the measurement accuracy of the electronic face bow under test by statistically analyzing the measurement deviation value of multiple measurements under different set values.

[0007] Furthermore, the receiver of the electronic face bow is rigidly connected to the maxillary body of the jaw frame via a strip support plate; the receiver is bonded to one end of the strip support plate, and the other end of the strip support plate is fixed to the maxillary body; The transmitter of the electronic face bow is bonded to the jaw support surface, and the distance between the center of the transmitter and the front end of the jaw frame is kept within a threshold range.

[0008] Furthermore, the test indicators include: the incision guide angle of the jaw frame, the left side incision guide angle, and the right side incision guide angle; the left condyle protrusion guide angle, the left condyle left side condyle guide angle, the right condyle protrusion guide angle, and the right condyle right side condyle guide angle of the jaw frame.

[0009] Furthermore, before conducting accuracy testing, the receiver's parameters are calibrated using a jaw frame; specifically, this includes: Lock the central axis of the jawbone frame, lift the maxilla of the jawbone frame, and rotate it around the central axis within a certain angle range; record the sequence of receiver pose data during the rotation process. Based on the receiver pose data sequence and the relative pose relationship between the receiver and the left and right condyles of the jaw frame, the coordinate sequence of the left and right condyles of the jaw frame in the transmitter coordinate system is calculated; The coordinate sequence is corrected using an optimization method so that the deviation between the Euclidean distance calculated during the rotation of the corrected left and right condyles and the Euclidean distance obtained by the structural constraint on the jaw frame is less than the deviation threshold. During the correction process, the pose correction amount of the receiver in the transmitter coordinate system is obtained to form a correction coefficient matrix for calibrating the receiver pose parameters.

[0010] Furthermore, during the testing process, When simulating the forward or backward movement of the mandible Control the incision guide pin of the jaw frame to move forward or backward along the incision guide disc; make the left and right condyles of the jaw frame slide along the condylar fossa until they reach the structural limit, and then return to the origin; repeat the above steps N times and record the trajectory data of the receiver during the process; When simulating left or right side movement of the mandible, Control the incisor needle of the jaw frame to move left or right along the incisor disc; make the left or right condyle slide laterally along the condylar fossa until it reaches the structural limit, and then return to the origin; repeat the above steps N times and record the trajectory data of the receiver during the process.

[0011] Furthermore, the testing process during the simulation of mandibular protrusion or retraction includes: During forward or backward movement, the receiver's measurement data within the transmitter's coordinate system is obtained; Perform coordinate transformation to calculate the position coordinates of the incision guide needle in the mandibular coordinate system and the position coordinates of the left and right condyles in the maxillary coordinate system; Plot the trajectory curves of the cutting guide needle in the mandibular coordinate system and the trajectory curves of the left and right condyles in the maxillary coordinate system when the protrusion or retraction movements are performed. The angles between the sagittal projections of the three curves onto the jawbone and the first reference plane are calculated, and the measured values ​​of the anterior condylar protrusion guide angle, the left condylar protrusion guide angle, and the right condylar protrusion guide angle are obtained, respectively. , and ; The first reference plane is the jaw support surface.

[0012] Furthermore, the coordinates of the cutting guide needle in the mandibular coordinate system are... In the formula, This is the transformation matrix from the transmitter to the mandible. The transformation matrix from receiver to tangent pin. The coordinates of the receiver in the transmitter coordinate system; The coordinates of the left condyle in the maxillary coordinate system are: ; The coordinates of the right condyle in the maxillary coordinate system are: ; in, Let be the transformation matrix from the receiver to the left condyle. Let be the transformation matrix from the receiver to the right condyle. This is the transformation matrix from the left condyle to the simulated maxilla. This is the transformation matrix from the right condyle to the simulated maxilla.

[0013] Furthermore, the testing process during the simulation of left or right mandibular movement includes: When moving to the left or right, the receiver's measurement data in the transmitter's coordinate system is obtained; Perform coordinate transformation to calculate the position coordinates of the incision guide needle in the mandibular coordinate system and the coordinates of the left or right condyle in the maxillary coordinate system; When moving to the left, draw the trajectory curve of the incision guide needle in the mandibular coordinate system and the trajectory curve of the left condyle in the maxillary coordinate system; The measured value of the left-side tangential slope is determined based on the tangential trajectory of the left-side motion. The measured value of the left condyle guide slope was determined based on the trajectory of the left condyle during left-side movement. ; When moving to the right side, draw the trajectory curve of the incision guide needle in the mandibular coordinate system and the trajectory curve of the right condyle in the maxillary coordinate system; The measured value of the right-side tangential slope is determined based on the tangential trajectory of the right-side motion. The measured value of the right condyle guide slope was determined based on the trajectory of the right condyle during right-side movement. .

[0014] Furthermore, during left-side movement, the position coordinates of the guide needle within the mandibular coordinate system... ,in, This is the transformation matrix from the transmitter to the mandible. Let be the transformation matrix from receiver to guide pin; the receiver's coordinates in the transmitter coordinate system are... ; The coordinates of the left condyle in the maxillary coordinate system are: , This is the transformation matrix from the left condyle to the maxilla. This is the transformation matrix from the receiver to the left condyle; When moving to the right, the position coordinates of the guide pin in the mandibular coordinate system ; The transformation matrix from receiver to tangent pin. The transformation matrix from transmitter to mandible; the receiver's coordinates in the transmitter coordinate system are... ; The coordinates of the right condyle in the maxillary coordinate system ; Let be the transformation matrix from the receiver to the right condyle. This is the transformation matrix from the right condyle to the maxilla.

[0015] Furthermore, obtaining the measurement accuracy of the tested electronic face bow by statistically analyzing the measurement deviation values ​​of multiple measurements under different set values ​​includes: [the following is a partial translation of the original text, which is incomplete and requires further context.] The value is set to the measurement accuracy of this angle; This is the root mean square value.

[0016] This invention can achieve at least one of the following beneficial effects: The present invention utilizes a jaw frame to provide a stable reference plane and combines the electronic facebow with the jaw frame. By simulating the movement of the human head's mandible, the trajectory is measured. Then, the angle between the movement trajectory and the reference plane is calculated, and finally, the angle measurement accuracy is evaluated by statistical methods. This system achieves accurate testing of the electronic facebow angle, and the testing process is efficient and reliable. Attached Figure Description

[0017] The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts.

[0018] Figure 1 This is a schematic diagram showing the components and connections of the electronic face bow angle accuracy testing system in an embodiment of the present invention; Figure 2 This is a schematic diagram of the jaw frame mechanism in an embodiment of the present invention; Figure 3 This is a schematic diagram of the coordinate system of the receiver or transmitter of the electronic face bow in an embodiment of the present invention; Figure 4 This is a schematic diagram of the data analysis process of the test terminal during the simulated mandibular protrusion or retraction movement in an embodiment of the present invention. Figure 5 This is a schematic diagram of the data analysis process of the test terminal during the simulation of left-side or right-side movement in an embodiment of the present invention. Detailed Implementation

[0019] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which form part of this application and, together with the embodiments of the present invention, serve to illustrate the principles of the present invention.

[0020] One embodiment of the present invention discloses an electronic facebow angle accuracy testing system utilizing a medical jaw frame, such as... Figure 1 As shown, it includes: a jaw frame, an electronic face bow under test, and a test terminal; The electronic face bow under test includes a transmitter, a receiver, and a main unit. The electronic face bow under test uses the principle of electromagnetic signal positioning to fix the position of the transmitter and make the receiver move with the mandible. The movement of the mandible is analyzed by the electromagnetic signals emitted by the transmitter and received by the receiver.

[0021] The transmitter of the electronic face bow is fixed on the same plane as the jaw frame; the receiver of the electronic face bow is rigidly connected to the maxillary body of the jaw frame through a tooling; the main unit of the electronic face bow is electrically connected to the test terminal. like Figure 2 As shown, the jaw frame is a medical jaw frame, preferably an average value jaw frame; it is used to set the set values ​​of the test indicators; and when simulating mandibular protrusion, retraction, left or right lateral movement with the set values, it drives the receiver shown to move together; During the simulated mandibular movement, the main unit of the electronic facebow measures the pose data of the receiver; The test terminal is used to calculate the measured value of the test index and the measurement deviation value between the measured value and the set value based on the pose data; and to estimate the measurement accuracy of the electronic face bow by statistically analyzing the measurement deviation values ​​of multiple measurements under different set values.

[0022] Specifically, the transmitter of the electronic face bow and the jaw frame are fixed on the same plane as the test fixture plane; the receiver of the electronic face bow is rigidly connected to the maxillary body of the jaw frame through a strip support plate; the receiver is bonded to one end of the strip support plate; the other end of the strip support plate is fixed to the maxillary body; Preferably, after connection, the distance between the receiver and the front end of the jaw frame is 20cm.

[0023] The transmitter of the electronic face bow is bonded to the jaw support surface, and the distance between the center of the transmitter and the front end of the jaw support is maintained within a threshold range. Preferably, the threshold range is no more than 15cm.

[0024] Specifically, the test indicators include tangential slope and condylar slope: where, The incision guide angle includes: the incision guide angle of the jaw frame protruding incision guide, the left side incision guide angle, and the right side incision guide angle; Condylar guidance angles include: left condylar protrusion guidance angle, left condylar left lateral condyle guidance angle, right condylar protrusion guidance angle, and right condylar right lateral condyle guidance angle.

[0025] During the simulated jaw movement, the main unit of the electronic facebow measures the position data of the receiver, including three-axis position data of X, Y, and Z axes and three-axis attitude data including yaw angle, pitch angle, and roll angle.

[0026] like Figure 3 The figure shows a schematic diagram of the coordinate system of the receiver or transmitter position of the electronic face bow.

[0027] In the specific testing process of this embodiment, in accordance with Figure 1 After the system was set up as shown, it was powered on. The system was fault-free and preheated for 20 minutes.

[0028] Before conducting the accuracy test, in order to improve the accuracy of the test, this embodiment also uses a jaw frame to calibrate the receiver parameters. Specifically, it includes: 1) Lock the central axis of the jaw frame, lift the maxilla of the jaw frame, and rotate it around the central axis within a certain angle range; record the pose data sequence measured by the electronic face bow receiver during the rotation; the angle range is 30°~50°.

[0029] 2) Based on the receiver pose data sequence and the relative pose relationship between the receiver and the left and right condyles of the jaw frame, calculate the coordinate sequence of the left and right condyles of the jaw frame in the transmitter coordinate system; The calculation method is as follows: the three-dimensional coordinates of the left and right condyles in the receiver coordinate system are obtained by manual measurement. and Simultaneously, the three-dimensional coordinates of the receiver in the transmitter coordinate system are obtained through electronic face bow measurement. Then the coordinates of the left and right condyles of the jawbone in the launcher coordinate system can be calculated. , ; Once the relative position of the receiver and the jaw frame is determined, the relative pose relationship between the receiver and the left and right condyles of the jaw frame is determined. The relative pose relationship can be obtained by measurement, and the relative pose includes the relative position and the relative posture.

[0030] 3) The coordinate sequence is corrected using the simulated annealing optimization method so that the deviation between the Euclidean distance calculated by the corrected left and right condyles during rotation and the Euclidean distance (110mm) obtained by the structural limit on the jaw frame is less than the deviation threshold of 1mm; during the correction process, the pose correction amount of the receiver in the transmitter coordinate system is obtained to form a correction coefficient matrix for calibrating the pose parameters of the receiver.

[0031] The correction coefficient matrix ,in For receiver X-axis coordinate deviation, For receiver Y-axis coordinate deviation, For the Z-axis coordinate deviation of the receiver, For receiver heading angle deviation, For receiver pitch angle deviation, This refers to the receiver roll angle deviation.

[0032] The deviation threshold is 1 mm. This correction factor will be subtracted from all subsequent receiver measurements, and will not be discussed further thereafter.

[0033] After the system parameters are calibrated, jaw movement data are collected.

[0034] First, the test parameters were set. Multiple sets of jawbone parameters, each with 7 parameters, were randomly generated. The 7 parameters were the set values ​​for the incisor guide angle, the left side incisor guide angle, the right side incisor guide angle, the left condyle angle, the left side condyle angle, the right condyle angle, and the right side condyle angle. Table 1 shows the set values ​​for 20 sets of jawbone parameters.

[0035] Table 1. Cervical artery parameter settings / °

[0036] The jaw frame is set according to the set values ​​of the incisal guide angle and the condylar guide angle, including: Unlock the cervical artery center lock, loosen the left condyle side locking screw, and then tighten the locking screw after setting the left condyle protrusion guide slope and the left quadrangular condyle guide slope; Loosen the right condyle side locking screw, set the guide slope of the right anterior condyle and the guide slope of the right lateral condyle, and then tighten the locking screw; Loosen the guide pin locking screw, set the guide pin forward extension angle, left side guide angle, and right side guide angle, then tighten the locking screw.

[0037] During the simulated forward, backward, left, and right lateral movements of the mandible, the test terminal records trajectory data composed of receiver pose data during the movement.

[0038] Specifically, during the testing process, When simulating the forward or backward movement of the mandible Hold the incision guide pin with your hand and control the incision guide pin of the jaw frame to move forward or backward along the incision guide disc; at this time, the left and right condyles of the jaw frame will slide along the condylar fossa until they reach the structural limit, and then slowly return to the origin; repeat the above steps N times and record the receiver trajectory data during the process; When simulating leftward movement of the mandible, Hold the incision guide pin with your hand and control the incision guide pin of the jaw frame to move to the left side along the incision guide disc; at this time, the left condyle will slide laterally along the condylar fossa until it reaches the structural limit, and then slowly return to the origin; repeat the above steps N times and record the receiver trajectory data during the process; When simulating right-side movement of the mandible, Hold the incision guide pin with your hand and control the incision guide pin of the jaw frame to move to the right side along the incision guide plate; at this time, the right condyle will slide laterally along the condylar fossa until it reaches the structural limit, and then slowly return to the origin; repeat the above steps N times and record the receiver trajectory data during the process.

[0039] Preferably, the number of repetitions N=3.

[0040] The test indicators are measured based on the pose data in the test terminal. The data analysis process includes: When simulating the forward or backward movement of the mandible, the incision guide angle of the incision guide needle, the condyle guide angle of the left condyle, and the condyle guide angle of the right condyle are obtained based on the trajectory data of the receiver. When simulating the left-side movement of the mandible, the left-side incision guide angle of the incision guide needle and the left-side condyle guide angle of the left condyle are obtained based on the receiver trajectory data; When simulating the right-side movement of the mandible, the right-side incision guide angle and the right-side condyle guide angle are obtained based on the receiver trajectory data.

[0041] Specifically, During the simulation of mandibular protrusion or retraction movements, the data analysis process of the testing terminal, such as... Figure 4 As shown, it includes: 1) During forward or backward movement, obtain measurement data of the receiver in the transmitter coordinate system; 2) Perform coordinate transformation to calculate the position coordinates of the incision guide needle in the mandibular coordinate system and the coordinates of the left and right condyles in the maxillary coordinate system; the coordinate transformation includes coordinate rotation and translation transformations; Specifically, the coordinates of the cutting guide needle in the mandibular coordinate system are: In the formula, The transformation matrix from receiver to tangent pin. This is the transformation matrix from the transmitter to the mandible. The coordinates of the receiver in the transmitter coordinate system during forward or backward motion; The coordinates of the left condyle in the maxillary coordinate system are: ; The coordinates of the right condyle in the maxillary coordinate system are: ; in, Let be the transformation matrix from the receiver to the left condyle. Let be the transformation matrix from the receiver to the right condyle. This is the transformation matrix from the left condyle to the simulated maxilla. This is the transformation matrix from the right condyle to the simulated maxilla. Each transformation matrix includes translation and rotation parameters.

[0042] 3) Based on the coordinates of the incision guide in the mandibular coordinate system and the coordinates of the left and right condyles in the maxillary coordinate system, draw the trajectory of the incision guide in the mandibular coordinate system and the trajectory of the left and right condyles in the maxillary coordinate system during the protrusion or retraction movements. 4) Calculate the angles between the projections of the three curves onto the sagittal plane and the first reference plane, and obtain the measured values ​​of the anterior tangential guide angle, the left condyle anterior condyle guide angle, and the right condyle anterior condyle guide angle, respectively. , and .

[0043] The first reference plane is the jaw support surface, which is a horizontal plane when the jaw frame is placed horizontally.

[0044] During the simulation of left or right mandibular movement, the testing process of the testing terminal is as follows: Figure 5 As shown, it includes: 1) When moving to the left or right, obtain the measurement data of the receiver in the transmitter coordinate system; 2) Perform coordinate transformation to calculate the position coordinates of the incision guide needle in the mandibular coordinate system and the coordinates of the left or right condyle in the maxillary coordinate system; the coordinate transformation includes coordinate rotation and translation transformations; When moving to the left, Position coordinates of the cutting guide needle in the mandibular coordinate system ,in, The transformation matrix from receiver to tangent pin. This is the transformation matrix from the transmitter to the mandible; The coordinates of the receiver in the transmitter coordinate system; The coordinates of the left condyle in the maxillary coordinate system are: , Let be the transformation matrix from the receiver to the left condyle. This is the transformation matrix from the left condyle to the maxilla; When moving to the right, Position coordinates of the cutting guide needle in the mandibular coordinate system ; The transformation matrix from receiver to tangent pin. This is the transformation matrix from the transmitter to the mandible; The coordinates of the receiver in the transmitter coordinate system; The coordinates of the right condyle in the maxillary coordinate system ; Let be the transformation matrix from the receiver to the right condyle. This is the transformation matrix from the right condyle to the maxilla.

[0045] 3) When moving to the left, draw the trajectory curve of the incision guide needle in the mandibular coordinate system and the trajectory curve of the left condyle in the maxillary coordinate system; 4) Determine the measured value of the left-side tangential slope based on the tangential trajectory of the left-side motion. The measured value of the left condyle guide slope was determined based on the trajectory of the left condyle during left-side movement. ; Specifically, during the leftward movement, the angle between the line connecting the starting and ending points of the tangential trajectory and the set second reference plane is measured as the leftward tangential slope. Calculate the angle between the line connecting the start and end points of the left condyle trajectory and the third reference plane, which is the measured value of the left condyle slope. .

[0046] The second reference plane can be a commonly used reference plane in existing methods, based on the measurement principle of tangential inclination. The third reference plane can be the sagittal plane of the jawbone.

[0047] 5) When moving to the right side, draw the trajectory curve of the guide needle in the mandibular coordinate system and the trajectory curve of the right condyle in the maxillary coordinate system; 6) Determine the measured value of the right-side tangential slope based on the tangential trajectory of the right-side motion. The measured value of the right condyle guide slope was determined based on the trajectory of the right condyle during right-side movement. .

[0048] Specifically, during the movement to the right, the angle between the line connecting the starting and ending points of the tangential trajectory and the set fourth reference plane is measured as the tangential slope on the right. Calculate the measured value of the guide slope of the right condyle, which is the angle between the line connecting the starting and ending points of the right condyle trajectory and the third reference plane. .

[0049] The fourth reference plane can be a commonly used reference plane in existing methods, based on the measurement principle of tangential inclination. The third reference plane can be the sagittal plane of the jawbone.

[0050] Through multiple tests, the angles obtained from the various motion trajectories received by the test terminal are as follows: ; In the test terminal, the set value is removed from the obtained angle sequence, and the resulting angle deviation sequence is: ; In this embodiment, each angle deviation sequence follows a normal distribution. By taking multiple measurements at different set values, the measurement deviation values ​​are statistically analyzed to obtain the angle deviation sequence for each angle in the test index. The angle deviation data for each angle is then collected. The value is set to the measurement accuracy of this angle. This is the root mean square value.

[0051] The accuracy of electronic face bow angle measurement is: .

[0052] The accuracy of the electronic face bow angle measurement enables the detection and screening of electronic face bows.

[0053] In summary, the electronic facebow angle accuracy testing system of this invention utilizes a jaw frame to provide a stable reference plane and combines the electronic facebow with the jaw frame. It achieves trajectory measurement by simulating the movement of the human head's mandible, then calculates the angle between the movement trajectory and the reference plane, and finally evaluates the angle measurement accuracy through statistical methods. This achieves electronic facebow angle accuracy testing, and the testing process is efficient and reliable.

[0054] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. An electronic facebow angle accuracy testing system utilizing a medical jaw frame, characterized in that, include: Jaw frame, the electronic face bow under test, and the test terminal; The transmitter of the electronic face bow is fixed on the same plane as the jaw frame; The receiver of the electronic face bow is rigidly connected to the maxillary body of the jaw frame via a tooling; the main unit of the electronic face bow is electrically connected to the test terminal. The jaw frame is used to set the preset values ​​of the test indicators, and when simulating the forward, backward, left or right movement of the mandible at the preset values, it drives the receiver to move together; During the simulated mandibular movement, the main unit of the electronic facebow measures the pose data of the receiver; The test terminal is used to calculate the measured value of the test index and the measurement deviation value between the measured value and the set value based on the pose data. The measurement accuracy of the tested electronic face bow was obtained by statistically analyzing the measurement deviation values ​​of multiple measurements under different setting values.

2. The electronic face bow angle accuracy testing system according to claim 1, characterized in that, The receiver of the electronic face bow is rigidly connected to the maxillary body of the jaw frame through a strip support plate; the receiver is bonded to one end of the strip support plate, and the other end of the strip support plate is fixed to the maxillary body; The transmitter of the electronic face bow is bonded to the jaw support surface, and the distance between the center of the transmitter and the front end of the jaw frame is kept within a threshold range.

3. The electronic face bow angle accuracy testing system according to claim 1 or 2, characterized in that, The test indicators include: the incision guide angle, left-side incision guide angle, and right-side incision guide angle of the jaw frame; the left condyle protrusion guide angle, left condyle left-side condyle guide angle, right condyle protrusion guide angle, and right condyle right-side condyle guide angle of the jaw frame.

4. The electronic face bow angle accuracy testing system according to claim 3, characterized in that, Before conducting accuracy testing, the receiver parameters are calibrated using a jaw frame; specifically including: Lock the central axis of the jawbone frame, lift the maxilla of the jawbone frame, and rotate it around the central axis within a certain angle range; record the sequence of receiver pose data during the rotation process. Based on the receiver pose data sequence and the relative pose relationship between the receiver and the left and right condyles of the jaw frame, the coordinate sequence of the left and right condyles of the jaw frame in the transmitter coordinate system is calculated; The coordinate sequence is corrected using an optimization method so that the deviation between the Euclidean distance calculated during the rotation of the corrected left and right condyles and the Euclidean distance obtained by the structural constraint on the jaw frame is less than the deviation threshold. During the correction process, the pose correction amount of the receiver in the transmitter coordinate system is obtained to form a correction coefficient matrix for calibrating the receiver pose parameters.

5. The electronic face bow angle accuracy testing system according to claim 3, characterized in that, During the testing process, When simulating the forward or backward movement of the mandible Control the incision guide pin of the jaw frame to move forward or backward along the incision guide disc; make the left and right condyles of the jaw frame slide along the condylar fossa until they reach the structural limit, and then return to the origin; repeat the above steps N times and record the trajectory data of the receiver during the process; When simulating left or right side movement of the mandible, Control the incisor needle of the jaw frame to move left or right along the incisor disc; make the left or right condyle slide laterally along the condylar fossa until it reaches the structural limit, and then return to the origin; repeat the above steps N times and record the trajectory data of the receiver during the process.

6. The electronic face bow angle accuracy testing system according to claim 5, characterized in that, The testing process during simulated mandibular protrusion or retraction includes: During forward or backward movement, the receiver's measurement data within the transmitter's coordinate system is obtained; Perform coordinate transformation to calculate the position coordinates of the incision guide needle in the mandibular coordinate system and the position coordinates of the left and right condyles in the maxillary coordinate system; Plot the trajectory curves of the cutting guide needle in the mandibular coordinate system and the trajectory curves of the left and right condyles in the maxillary coordinate system when the protrusion or retraction movements are performed. The angles between the sagittal projections of the three curves onto the jawbone and the first reference plane are calculated, and the measured values ​​of the anterior condylar protrusion guide angle, the left condylar protrusion guide angle, and the right condylar protrusion guide angle are obtained, respectively. , and ; The first reference plane is the jaw support surface.

7. The electronic face bow angle accuracy testing system according to claim 6, characterized in that, The coordinates of the cutting guide needle in the mandibular coordinate system are: In the formula, This is the transformation matrix from the transmitter to the mandible. The transformation matrix from receiver to tangent pin. The coordinates of the receiver in the transmitter coordinate system; The coordinates of the left condyle in the maxillary coordinate system are: ; The coordinates of the right condyle in the maxillary coordinate system are: ; in, Let be the transformation matrix from the receiver to the left condyle. Let be the transformation matrix from the receiver to the right condyle. This is the transformation matrix from the left condyle to the simulated maxilla. This is the transformation matrix from the right condyle to the simulated maxilla.

8. The electronic face bow angle accuracy testing system according to claim 3, characterized in that, The testing process, which simulates left or right mandibular movement, includes: When moving to the left or right, the receiver's measurement data in the transmitter's coordinate system is obtained; Perform coordinate transformation to calculate the position coordinates of the incision guide needle in the mandibular coordinate system and the coordinates of the left or right condyle in the maxillary coordinate system; When moving to the left, draw the trajectory curve of the incision guide needle in the mandibular coordinate system and the trajectory curve of the left condyle in the maxillary coordinate system; The measured value of the left-side tangential slope is determined based on the tangential trajectory of the left-side motion. The measured value of the left condyle guide slope was determined based on the trajectory of the left condyle during left-side movement. ; When moving to the right side, draw the trajectory curve of the incision guide needle in the mandibular coordinate system and the trajectory curve of the right condyle in the maxillary coordinate system; The measured value of the right-side tangential slope is determined based on the tangential trajectory of the right-side motion. The measured value of the right condyle guide slope was determined based on the trajectory of the right condyle during right-sided movement. .

9. The electronic face bow angle accuracy testing system according to claim 8, characterized in that, When moving to the left, Position coordinates of the cutting guide needle in the mandibular coordinate system ,in, This is the transformation matrix from the transmitter to the mandible. Let be the transformation matrix from receiver to guide pin; the receiver's coordinates in the transmitter coordinate system are... ; The coordinates of the left condyle in the maxillary coordinate system are: , This is the transformation matrix from the left condyle to the maxilla. This is the transformation matrix from the receiver to the left condyle; When moving to the right, Position coordinates of the cutting guide needle in the mandibular coordinate system ; The transformation matrix from receiver to tangent pin. The transformation matrix from transmitter to mandible; the receiver's coordinates in the transmitter coordinate system are... ; The coordinates of the right condyle in the maxillary coordinate system ; Let be the transformation matrix from the receiver to the right condyle. This is the transformation matrix from the right condyle to the maxilla.

10. The electronic face bow angle accuracy testing system according to claim 3, characterized in that, The measurement accuracy of the tested electronic face bow is obtained by statistically analyzing the measurement deviation values ​​of multiple measurements under different set values. This includes: analyzing the angular deviation sequence of each angle in the statistical test indicators. The value is set to the measurement accuracy of this angle; This is the root mean square value.

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