WO2023010888A1

WO2023010888A1 - Three-dimensional detection device and positioning method for dental implant based on constant current source

Info

Publication number: WO2023010888A1
Application number: PCT/CN2022/087373
Authority: WO
Inventors: 郭丹; 张倜然
Original assignee: 长沙微笑美齿智能科技有限公司
Priority date: 2021-08-04
Filing date: 2022-04-18
Publication date: 2023-02-09
Also published as: DE112022000078T5; CN113509285A

Abstract

The present invention relates to the field of anti-interference and high-sensitivity gum implant detection, and in particular to a three-dimensional detection device and positioning method for a dental implant based on a constant current source. The three-dimensional detection device comprises a detection sensor, a detection sensor socket, and an implant positioning device, and two ends of the detection sensor socket are respectively connected to the detection sensor and the implant positioning device; the detection sensor comprises a PCB substrate and detection coils respectively disposed on the front and back surfaces of the PCB substrate, and the transverse and longitudinal sizes of the involute racetrack-shaped coil on the back surface are 0.1 mm smaller than those of the involute racetrack-shaped coil on the front surface; and the implant positioning device mainly comprises a CPU, a constant voltage source module, a state display control module, and a frequency conversion module which are powered by a power supply. The present invention has the advantages of being high in sensitivity, convenient to operate and accurate in positioning, and the problems that existing methods are long in period, inaccurate in positioning, and low in positioning speed, etc. are solved, thereby ensuring that a doctor rapidly and accurately finds an implant and implements an operation, and reducing medical negligence.

Description

Three-dimensional detection and positioning method for dental implants based on constant current source

technical field

The invention belongs to the field of anti-interference and high-sensitivity detection of dental implants, in particular to a three-dimensional detection and positioning method for dental implants based on a constant current source.

Background technique

With the improvement of people's life, more and more patients with tooth defects and missing teeth will choose to use implants and crowns to restore the dental chewing function of the oral cavity; After a long time, once the crown falls off, the implant will be completely covered by the muscle that grows from the wound healing; it is impossible to tell where the implant has been placed on the jawbone with the naked eye. How to find these disrepaired implants embedded in the jawbone and covered by muscles is a technical problem; now some doctors use X-ray equipment to take X-rays of the oral cavity to find the approximate position of the implants in the oral cavity However, the detection results are sometimes inaccurate, because the X-ray machine can only scan and image the teeth in the frontal section of the mouth. When there are several implants in the oral cavity, such as implants, the images of the implants will overlap or deform, making it difficult to determine the exact position of the implants, so it is easy to cause medical accidents during the operation. . Therefore, how to find the specific position of the implant in the oral cavity accurately and without omission before the operation is an urgent problem to be solved.

When people's teeth fall out, it is usually necessary to fix dental implants on the gums, and then fix the crowns on the implants, so that the newly filled teeth can play the role of chewing food normally. However, the service life of the crown fixed on the implant is usually about five years. After the time is up, the crown will fall off. With the growth of the muscles on the gum bed, the implant will be covered after a period of time. When the tooth is treated again , it often happens that the dental implants buried in the gums cannot be found, so it is very important to determine the upper and lower positions and specific positions of the dental implants accurately, conveniently and quickly for timely treatment of the teeth. The invention is a PCB-based anti-interference dental implant detection head, which can not only quickly identify whether the implant is in the upper jaw or the lower jaw, but also determine its specific position.

Contents of the invention

The purpose of the present invention is to make a dental implant detection head that is easy to manufacture and has high sensitivity, specifically a three-dimensional detection and positioning method for dental implants based on a constant current source, so as to ensure portability and improve detection accuracy at the same time.

The present invention is realized through the following technical solutions, including a detection sensor, a detection sensor socket and an implant positioning device, and the two ends of the detection sensor socket are respectively connected to the detection sensor and the implant positioning device;

The detection sensor includes a PCB substrate, and detection coils respectively arranged on the front and back surfaces of the PCB substrate, and also includes a central hole arranged in the middle of the PCB substrate, and a via hole connecting the detection coils on the front and back surfaces of the PCB substrate; the detection coil includes Two-layer copper involute racetrack-shaped coils arranged on the front and back surfaces of the PCB substrate; the lateral and longitudinal dimensions of the involute racetrack-shaped coils on the reverse side are 0.1mm smaller than those on the front side; the detection coil passes through the electrodes connected to the power supply powered by;

The implant positioning device mainly includes a CPU powered by a power supply, a constant voltage source module, a state display control module and a frequency conversion module;

One end of the detection sensor socket is used for plugging and installing the detection sensor, and the other end is used for plugging in the front end of the implant positioning device, and the PCB is connected to the power supply through the detection sensor socket;

The constant voltage source module, the state display control module and the frequency conversion module are connected to the CPU, and the PCB is connected to the CPU through a detection sensor socket;

The frequency conversion module automatically outputs the required frequency range under the control of the CPU according to the selected frequency gear, and performs frequency conversion scanning from low to high within the set frequency range;

The PCB base is made of glass fiber cloth-based FR-4 material, with a thickness of 1.0mm, or a thickness of 1.2mm, or a thickness of 1.5mm;

The copper material of the detection coil has a thickness of 35um, a width of 0.2mm to 0.25mm, and a coil spacing of 0.1mm to 0.15mm. The detection coil on the front of the PCB substrate gradually shrinks from outside to inside, with a total of 6 turns; and through the via hole and the PCB substrate The detection coils on the back are connected, and the detection coils on the back gradually increase from the inside to the outside, a total of 6 turns, and the center line of the detection coils on the back is located at the center line of the gap of the front detection coils;

The longitudinal dimension of the detection coil on the front is 5.5mm to 6.6mm, and the transverse dimension is 6.5mm to 7.6mm; the length of the straight part of the involute racetrack coil is 2mm to 3mm;

The radius of the involute track-shaped semicircular coil from the outside to the inside is based on 5.5mm, 4.9mm, 4.3mm, 3.7mm, 3.1mm and 2.5mm, and changes positively within 0 to 0.1mm;

The transverse dimension of the involute racetrack-shaped coil is sequentially based on 6.5mm, 5.9mm, 5.3mm, 4.7mm, 4.1mm and 3.5mm from outside to inside, and changes positively within 0 to 0.1mm;

The diameter of the central hole of the PCB base is 2mm to 3mm, and copper is poured around the central hole;

The diameters of the three via holes connecting the detection coils on the front and back surfaces of the PCB substrate are 500um to 700um, and they are distributed in an obtuse triangle.

The magnetic field distribution generated by the detection coil on the front of the PCB substrate is concave; the frequency of the sinusoidal alternating current passed by the detection coil can be adjusted between 230kHz and 240kHz, and the peak voltage fluctuates between 400mV and 450mV during normal operation.

The detection sensor socket rotates within the range of 0° to 90°, 90° to 180°, and 180° to 270° in the implant positioning device; the detection sensor socket is arranged on the implant positioning device through the insertion end. In the hole; that is, the detection sensor rotates within the range of 0° to 90°, 90° to 180°, and 180° to 270° in the control device;

The insertion end of the detection sensor socket is a cylindrical structure, and a limit boss is set at the 0° position; the outer side of the insertion end is covered with a diamond-shaped shrapnel, and the shrapnel is fixed in the jack through the limit step on the inner wall of the jack, and the jack is also It includes positioning grooves for accommodating the four corners of the diamond-shaped shrapnel; the angle between the limiting steps is 90°;

The detection sensor is a hollow structure with built-in cables.

The state display control module is arranged at the bending position of the implant positioning device, and the state display control module is divided into eight areas, and the eight areas are equipped with red and green LED lights; specifically, 0 to 5 display area and button one, button two; the circular 0 display area is set at the center of the circle; the periphery of the 0 display area is a ring structure formed by button one and button two, and the outermost periphery is a ring structure formed by display areas 1 to 5.

The power supply is a battery, which is arranged in the battery compartment at the end of the implant positioning device to provide working power for the detection sensor and the implant positioning device;

When the battery voltage is close to the critical point, the constant voltage source module is under the control of the CPU, and the constant voltage module circuit starts; to ensure the normal clinical use of the device and reduce the inefficient working time of the device; when the battery voltage is lower than the working threshold After that, the host cannot be turned on, prompting to replace the battery;

The frequency conversion module includes three frequency gears, the high frequency gear is 8 to 12MHz, the intermediate frequency gear is 4 to 8MHz, and the low frequency gear is 0.1 to 4MHz; the inner wall of the implant positioning device is also inlaid with a layer of 300um metal copper mesh Shield.

The length of the detection sensor is 34mm to 36mm, the maximum width is 6mm, and the thickness is 1mm; the front and back sides of the detection sensor are provided with helical metal coils, and the number of coil rings is 6; the material of the detection sensor is a printed circuit board, namely PCBI1505.

Turn on the instrument switch, and the detection sensor oscillates at the natural frequency. If the mandibular implant is detected, the detection sensor does not need to be rotated. If the maxillary implant is detected, the detection sensor should be rotated 180°, and then gradually approach the gingiva where the implant is buried from directly above. , in the process of approaching, the oscillation frequency of the detection sensor increases gradually, and the display of the instrument panel gradually rises, and then it moves slightly. The sensor rotates 90° and 270° to detect the implant from the outside and inside of the gingiva, respectively, and locates the marks in front and back of the gingiva, and finally accurately locates the implant buried in the gingiva with 3 marking points.

The positioning method of the present invention comprises the following steps:

Step 1. When the implant is not detected, the frequency f of the LC oscillation circuit is stable at 2.0 to 2.3 MHz, and the magnetic induction intensity B is stable at 0.245 to 0.250 mT;

Step 2, the relationship between the LC oscillation circuit frequency f (MHz) and the magnetic induction B (mT) when the implant is detected is: f=13.66/[1+(B/0.05) ^-0.71 ]-7.40;

Step 3, the relationship between the LC oscillating circuit frequency f (MHz) and the magnetic induction B (mT) when approaching the center of the implant is: f=-0.25/[1+(B/0.29) ^-26.82 ]+2.41; 4. When the center of the implant is located, the frequency f of the LC oscillation circuit is stable at 2.5 to 2.6 MHz, and the magnetic induction intensity B is stable at about 0.303 to 0.310 mT.

The LC oscillating circuit is composed of a coil and a capacitor of the detection sensor. When it is close to the implant in the gum and penetrates the 2.5mm-3mm thick gingiva, the inductance of the coil changes, and the frequency of the oscillating circuit changes with the The change, the transmission distance s (mm) and the frequency f (MHz) of the LC oscillator circuit satisfy:

s = 1.57e ^0.05f +1.

The formula for calculating the magnetic induction intensity of the involute runway-shaped detection coil is:

Taking the front coil as the xoy plane, the coordinate origin is located at the center of the central hole, so the distribution of the magnetic field above the xoy plane on the central axis is obtained as:

On the central axis, the distribution of the magnetic field below the xoy plane is:

Finally, on the central axis, the distribution of the total magnetic field is:

When the detection device is rotated 0° for detection, the direction of the magnetic field is parallel to the direction of the gums and vertically downwards to detect the implants in the lower jaw;

When rotating 180° for detection, the direction of the magnetic field is parallel to the direction of the gums and vertically upwards to detect the implants in the upper jaw;

When rotating 90° to detect from the outside of the gingiva, the direction of the magnetic field is perpendicular to the gingiva and inward to detect the implant on the outside of the maxillary or mandibular gingiva;

When rotating 270° to detect from the inside of the gum, the direction of the magnetic field is perpendicular to the gum and outwards to detect the implant on the inside of the maxillary or mandibular gum.

The working steps of the buzzer and display area are as follows:

Step 1, put a battery into the battery compartment of the implant positioning device, and then insert the detection sensor and the detection sensor socket into the front end of the implant positioning device as a whole;

Step 2, press button 2, the buzzer emits a short "beep" sound, each green light in the 0, 1, 2, 3, 4, 5 display area is on, and after 0.5 seconds, the green lights are all off; then the implant The positioning device enters the self-inspection state; if the self-inspection fails, the red lights in the 1, 2, 3, 4, and 5 display areas will glow in circles, that is, the five red lights will be on for 0.2 seconds each, and will automatically shut down after 1 second; If the self-test passes, the green lights in

areas

0, 1, 2, 3, 4, and 5 are always on;

Step 3, after pressing the button 1, the system enters the treatment state, at this time, the green lights in the 0, 1, 2, 3, 4, 5 display areas are flashing, on and off for 0.5 seconds each, and the cycle is carried out; when the detection sensor enters the medium and weak When detecting the area, the green light and red light in the 0, 1, 2, 3, 4, 5 display area are all on, showing orange; when the detection sensor enters the strong detection area, the green light in the 0 area is on, and the buzzer sends out two A long "beep" sound indicates that the implant has been found; after marking, continue to look for the next implant.

In the step 3, the following frequency conversion operations are also included:

Put the detection sensor deep into the oral cavity, rotate the detection sensor socket to make it easy to detect; press the treatment button, that is, press the button once; make the frequency gear at the lowest gear, and then move the detection sensor on the tooth surface, if the detection sensor has entered the implant At this time, the lights in the 1, 2, 3, 4, and 5 display areas are orange, that is, the red light and the green light are on at the same time; then continue to move, when the detection sensor is at the center of the implant, the green light in the 0 display area is on, and the other lights are on. No light; if the implant is not detected during the whole process, according to the selected gear, under the control of the CPU, after the frequency conversion processing of the frequency conversion module, the frequency gear is gradually adjusted from the middle frequency gear to the high frequency gear until the implant is detected .

The beneficial effects of the present invention are as follows: 1. The tooth implant detection coil developed is the optimal structure obtained after computer simulation and theoretical calculation, and is easy to manufacture and low in cost. 2. Because it is used in the oral cavity, its low cost can guarantee its one-time use; it avoids the infection of the detection coil by bacteria in the oral cavity, thereby preventing the spread of bacteria. 3. The magnitude of the current in the coil is only about 20mA, and the strength of the generated alternating magnetic field will not damage the biological tissues in the oral cavity. 4. The detection structure of the involute racetrack-shaped copper coil with positive and negative two-layer structure based on the PCB substrate ensures portability and improves detection accuracy at the same time. 5. Since the energy consumption of different frequency gears is different, this measure can save energy consumption as much as possible. 6. There is a frequency conversion device in the positioning device, which can automatically output the required frequency range under the control of the single-chip microcomputer according to the selected frequency gear, and can perform from low to high within the set frequency range. Frequency conversion scanning. 7. Metal copper mesh shielding layer to reduce the interference of external signals; corresponding measures have been taken in the design of the circuit part of the device, using low-speed chips that meet the requirements, using optocoupler devices to isolate the crosstalk of electrical signals, power supply , PCB routing, grounding, interface positions and other parts have taken anti-interference measures, so that the entire positioning device has excellent anti-interference ability. 8. There are different types of detection sensors, which can be replaced according to the needs of different dental patients. 9. The on-off state and combined state of two light-emitting diodes with different colors are related to the state of the detection sensor, which is convenient for quick positioning. 10. The sensor socket on the positioning device can be manually adjusted to rotate around the positioning device, which is convenient for detection operation. 11. The output of the positioning device adopts low-frequency AC signals, which will not cause radiation damage to any part of the oral cavity.

Description of drawings

Fig. 1 is a structural block diagram of an implant positioning device.

Fig. 2 is a structural schematic diagram of the present invention.

Figure 3 is a front view of the probe head.

Figure 4 is a schematic diagram of the reverse side of the probe head.

Fig. 5 is a simulation diagram of the magnetic field distribution around the probe head.

Fig. 6 is a distribution diagram of the magnetic field generated by the front coil of the probe.

Fig. 7 is a schematic diagram of the state display control module.

Fig. 8 is a schematic diagram of the detection sensor socket.

Fig. 9 is a cross-sectional view of the detection sensor socket.

Fig. 10 is the use of the present invention to detect intragingival implants with a rotation of 0°.

Fig. 11 is the use of the present invention to detect intragingival implants with a rotation of 180°.

Fig. 12 is to use the present invention to probe the implant from the outside of the gum at 90°.

Fig. 13 is a 270° probe of the implant from the inner side of the gum using the present invention.

Fig. 14 is a flowchart of the present invention.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with accompanying drawings 1 to 14. Obviously, the described embodiments are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

The present invention comprises a detection sensor 1, a detection sensor socket 2 and an implant positioning device 3, and the two ends of the detection sensor socket 2 are respectively connected to the detection sensor 1 and the implant positioning device 3;

The detection sensor 1 includes a PCB substrate 11, and detection coils 12 respectively arranged on the front and back surfaces of the PCB substrate 11, and also includes a central hole 13 arranged in the middle of the PCB substrate 11, and connected to the detection coils on the front and back surfaces of the PCB substrate 11. The via hole 14 of 12; the detection coil 12 includes two layers of copper involute racetrack-shaped coils arranged on the front and back surfaces of the PCB substrate 11; the lateral and longitudinal dimensions of the involute racetrack-shaped coil on the reverse side are 0.1mm smaller than the size of the front side; The detection coil 12 is powered by electrodes connected to the power supply; the detection sensor 1 has different types, that is, the size of the PCB is constant, but the number of turns of the coil attached to the upper and lower surfaces of the PCB can be changed to meet the needs of different groups of people.

The implant positioning device 3 mainly includes a CPU 32 powered by a power supply 31, a constant voltage source module 33, a status display control module 34 and a frequency conversion module 35; the implant positioning device 3 is the core of the entire device, and its structure is hand-held. It is 12 cm long and cylindrical with a diameter of 2 cm. The detection sensor socket 2 is bent at an angle of 30° as a whole at a distance of 2 cm from the top, and the diameter is gradually reduced, and the diameter of the port becomes 1.8 cm. This port is equipped with a detection sensor interface, which is a rotating structure and can rotate within 270° , easy to operate.

The front and rear sides of the implant positioning device 3 shell are inlaid with rubber protrusions to increase friction and prevent the positioning device from slipping.

One end of the detection sensor socket 2 is used for plugging and installing the detection sensor 1 , and the other end is used for plugging in the front end of the implant positioning device 3 , and the PCB is connected to the power supply 31 through the detection sensor socket 2 .

The constant voltage source module 33 , the status display control module 34 and the frequency conversion module 35 are connected to the CPU 32 , and the PCB is connected to the CPU 32 through the detection sensor socket 2 .

When in use, after the implant is detected by the detection sensor 1 entering the oral cavity, the detection electromagnetic signal will be converted into a level signal and transmitted to the CPU32; after the CPU32 receives the detection signal, it will process and analyze the information. After eliminating the interference information, it is confirmed that the implant is detected, and the status display control module 34 is driven by the power supply 31 to make a corresponding status display.

The frequency conversion module 35 automatically outputs the required frequency range under the control of the CPU 32 according to the selected frequency range, and performs frequency conversion scanning from low to high within the set frequency range.

The detection principle is: the inductance of the detection sensor coil is L ₁ , the resistance is R ₁ , the effective value of the voltage is E, the effective value of the current is I ₁ , and the angular frequency is ω. The equivalent eddy current inductance of the oral metal implant is L ₂ and the resistance is R ₂ , the effective value of eddy current I ₂ , the corresponding relationship between the detection sensor coil and the mutual inductance M of the oral metal implant is:

I ₁ R ₁ +jL ₁ ωI ₁ ＝E+jMωI ₂ (1)

jMωI ₁ ＝I ₂ R ₂ +jL ₂ ωI ₂ (2)

From formula (1) and formula (2), we can get:

When the detection sensor 1 is close to the oral metal implant, the equivalent inductance and equivalent resistance of the detection sensor coil will change due to the eddy current effect, so that the purpose of the metal implant can be achieved by detecting the change of the coil voltage.

The PCB base 11 is made of glass fiber cloth-based FR-4 material with a thickness of 1.0mm, or a thickness of 1.2mm, or a thickness of 1.5mm;

The copper material of the detection coil 12 has a thickness of 35um, a width of 0.2mm to 0.25mm, and a coil spacing of 0.1mm to 0.15mm. The detection coil 12 on the front side of the PCB substrate 11 gradually shrinks from outside to inside, with a total of 6 turns; and The detection coil 12 on the back of the PCB substrate 11 is connected through the via hole 14. The detection coil 12 on the back gradually increases from the inside to the outside, with a total of 6 turns. The center line of the detection coil 12 on the back is located at the center line of the gap of the front detection coil 12. ;

The detection coil 12 of the front has a longitudinal dimension of 5.5mm to 6.6mm, and a transverse dimension of 6.5mm to 7.6mm; the length of the linear part of the involute racetrack coil is 2mm to 3mm;

The diameter of the central hole 13 of the PCB substrate 11 is 2 mm to 3 mm, and the surrounding of the central hole 13 is covered with copper;

The three via holes 14 connecting the detection coils 12 on the front and back surfaces of the PCB substrate 11 have a diameter of 500um to 700um and are distributed in an obtuse triangle.

The magnetic field distribution generated by the detection coil 12 on the front side of the PCB substrate 11 is concave; the frequency of the sinusoidal alternating current passing through the detection coil 12 can be adjusted between 230kHz and 240kHz, and the peak voltage during normal operation is between 400mV and 450mV fluctuate between.

Described CPU32, what adopted is the patch type single-chip microprocessor. Its operating voltage range is 1.3V-1.5V, and it is an ultra-low power consumption microprocessor powered directly by the battery.

The detection sensor socket 2 rotates within the range of 0° to 90°, 90° to 180°, and 180° to 270° in the implant positioning device 3; the detection sensor socket 2 is arranged on the implant through the insertion end 21 In the socket 36 of the positioning device 3;

The insertion end 21 of the detection sensor socket 2 is a cylindrical structure, and a limit boss 22 is set at a position of 0°; In the socket 36, the socket 36 also includes positioning grooves 362 for accommodating the four corners of the diamond-shaped elastic pieces 23; the angles between the steps of the limiting platforms 361 are 90°;

The detection sensor socket 2 is a hollow structure with a built-in cable 24 .

The detection sensor socket 2 can rotate within the range of 0 to 270°, which is convenient for the detection of the upper and lower jaw dental implants. There are electrodes on the upper and lower ends of the detection sensor socket 2, no matter whether the detection sensor socket 2 is inserted in the forward direction or in the reverse direction, The whole device can work normally, and it is convenient to replace the detection sensor socket 2, saving time.

The state display control module 34 is arranged at the bend of the implant positioning device, and the state display control module 34 is divided into eight areas, and two LED lights, red and green, are installed in the eight areas; specifically, 0 to 5 display area 343, button 1 341, button 2 342; the circular 0 display area is set at the center of the circle; the periphery of the 0 display area is a ring structure composed of button 1 341 and button 2 342, and the outermost periphery is composed of 1 to 5 display areas the ring structure;

The power supply 31 is a battery, which is arranged in the battery compartment at the end of the implant positioning device 3 . Provide working power for the detection sensor 1 and the implant positioning device 3 .

When the battery voltage was close to the critical point, the constant voltage source module 33 was under the control of the CPU32, and the constant voltage module circuit began to start; the normal clinical use of the device was guaranteed, and the inefficient working time of the device was reduced; when the battery voltage was lower than the working After the threshold, the host cannot be turned on, prompting to replace the battery. The device is more convenient and faster than the existing method of using X-ray oral cavity scanning imaging to locate the implant, and has no radiation damage to the human body.

The frequency conversion module 35 includes three frequency gears, the high frequency gear is 8 to 12 MHz, the middle frequency gear is 4 to 8 MHz, and the low frequency gear is 0.1 to 4 MHz.

The inner wall of the implant positioning device 3 is also inlaid with a 300um metallic copper mesh shielding layer. To reduce the interference of external signals; the circuit part in the implant positioning device 3 has also taken corresponding measures in the design, adopting low-speed chips that meet the requirements, utilizing optocoupler devices to isolate the crosstalk of electrical signals, power supply, PCB Anti-interference measures have been taken for wiring, grounding, and interface positions, so that the entire positioning device has excellent anti-interference ability.

The present invention comprises the following steps:

Step 1, put an AA battery into the battery compartment of the implant positioning device 3, and then insert the detection sensor 1 and the detection sensor socket 2 into the front end of the implant positioning device 3 as a whole;

Step 2, press the button 2 342, the buzzer emits a short "beep" sound, each green light of the 0, 1, 2, 3, 4, 5 display area 343 is on, and after 0.5 seconds, the green lights are all off; then The implant positioning device 3 enters the self-inspection state; if the self-inspection fails, the red lights in the 1, 2, 3, 4, and 5 display areas 343 will glow in circles, that is, the five red lights will be on for 0.2 seconds in sequence, and after 1 second , automatically shut down; if the self-test passes, the green lights of 0, 1, 2, 3, 4, 5 display areas 343 are always on;

Step 3, after pressing the button 1 341, the system enters the treatment state, at this time, the green lights of the 0, 1, 2, 3, 4, 5 display area 343 are flashing, on and off for 0.5 seconds each, and the cycle is carried out; when the detection sensor 1 enters During the middle and weak detection areas, the green light and the red light of the 0, 1, 2, 3, 4, 5 display area 343 are all on, showing orange; when the detection sensor 1 enters the strong detection area, the green light of the 0 display area is on, The buzzer emits two long beeps, indicating that the implant has been found; after making a mark, continue to look for the next implant.

Said step 3 also includes the following frequency conversion operations:

Put the detection sensor 1 deep into the oral cavity, rotate the detection sensor socket 2 to make it easy to detect; press the treatment key, that is, press one 341; make the frequency gear at the lowest gear, and then move the detection sensor 1 on the tooth surface, if the detection sensor 1 has entered the planting area, at this time, the lights of the 1, 2, 3, 4, and 5 display areas 343 are orange, that is, the red light and the green light are on at the same time; then continue to move, when the detection sensor 1 is in the center of the implant, 0 The green light in the display area is on, and the other lights are off; if no implant is detected during the whole process, then according to the selected gear, under the control of the CPU32, through the frequency conversion processing of the frequency conversion module 35, the frequency range is gradually adjusted from the middle frequency range to the high frequency range. Shifts until the implant is detected.

Turn on the instrument switch, and the detection sensor 1 oscillates at the natural frequency. If the mandibular implant is detected, the detection sensor 1 does not need to be rotated. If the maxillary implant is detected, the detection sensor 1 is first rotated 180°, and then gradually approached from the top to the buried implant. Near the gingiva, during the approaching process, the oscillation frequency of the detection sensor 1 gradually increases, and the display on the instrument panel gradually rises, and then makes a small movement. When the oscillation frequency reaches above 2.5MHz, the indicator light of the instrument lights up, and at the same time, a positioning mark is made from above Then rotate the detection sensor 1 by 90° and 270° to detect the implant from the outside and inside of the gingiva respectively, and locate the marks in the front and back of the gingiva, and finally accurately locate the implant buried in the gingiva with 3 marking points.

The positioning method of the present invention comprises the following steps:

Step 3. The relationship between the LC oscillation circuit frequency f (MHz) and the magnetic induction B (mT) when approaching the center of the implant is: f=-0.25/[1+(B/0.29) ^-26.82 ]+2.41;

Step 4. When the center of the implant is located, the frequency f of the LC oscillation circuit is stable at 2.5 to 2.6 MHz, and the magnetic induction B is stable at about 0.303 to 0.310 mT.

s = 1.57e ^0.05f +1.

The calculation formula of the magnetic induction intensity of the detection coil 12 of involute runway shape is:

Finally, on the central axis, the distribution of the total magnetic field is:

As a preferred solution of the present invention, when the detection device is rotated 0° for detection, the direction of the magnetic field is parallel to the direction of the gums and vertically downwards to detect the implant of the mandible; when the detection device is rotated 180° for detection, the direction of the magnetic field is parallel to the direction of the gums and vertically upwards, Detect maxillary implants; rotate 90° to detect from the outside of the gums, the direction of the magnetic field is perpendicular to the gums and inwards, detect the implants on the outside of the maxillary or mandibular gums; rotate 270° to detect from the inside of the gums, the direction of the magnetic field is perpendicular to the gums and outwards , probing for maxillary or mandibular medial gingival implants.

Although the embodiments of the present invention have been shown and described, those skilled in the art can understand that various changes, modifications and substitutions can be made to these embodiments without departing from the principle and spirit of the present invention. and modifications, the scope of the invention is defined by the appended claims and their equivalents.

Claims

A three-dimensional detection device for dental implants based on a constant current source, characterized in that:

It includes a detection sensor, a detection sensor socket and an implant positioning device, and the two ends of the detection sensor socket are respectively connected to the detection sensor and the implant positioning device;

The detection sensor includes a PCB substrate, and detection coils respectively arranged on the front and back surfaces of the PCB substrate, and also includes a central hole arranged in the middle of the PCB substrate, and a via hole connecting the detection coils on the front and back surfaces of the PCB substrate; the detection coil includes Two-layer copper involute racetrack-shaped coils arranged on the front and back surfaces of the PCB substrate; the lateral and longitudinal dimensions of the involute racetrack-shaped coils on the reverse side are 0.1mm smaller than those on the front side; the detection coil passes through the electrodes connected to the power supply powered by;

The implant positioning device mainly includes a CPU powered by a power supply, a constant voltage source module, a state display control module and a frequency conversion module;

One end of the detection sensor socket is used for plugging and installing the detection sensor, and the other end is used for plugging in the front end of the implant positioning device, and the PCB is connected to the power supply through the detection sensor socket;

The constant voltage source module, the state display control module and the frequency conversion module are connected to the CPU, and the PCB is connected to the CPU through a detection sensor socket;

According to different selected frequency gears, the frequency conversion module automatically outputs the required frequency range under the control of the CPU, and performs frequency conversion scanning from low to high within the set frequency range.
The three-dimensional detection device for dental implants based on a constant current source according to claim 1, wherein the PCB base is made of glass fiber cloth-based FR-4 material with a thickness of 1.0 mm, or a thickness of 1.2 mm, or a thickness of 1.0 mm. 1.5mm;

The copper material of the detection coil has a thickness of 35um, a width of 0.2mm to 0.25mm, and a coil spacing of 0.1mm to 0.15mm. The detection coil on the front of the PCB substrate gradually shrinks from outside to inside, with a total of 6 turns; and through the via hole and the PCB substrate The detection coils on the back are connected, and the detection coils on the back gradually increase from the inside to the outside, a total of 6 turns, and the center line of the detection coils on the back is located at the center line of the gap of the front detection coils;

The longitudinal dimension of the front detection coil is 5.5mm to 6.6mm, and the transverse dimension is 6.5mm to 7.6mm; the length of the straight part of the involute racetrack coil is 2mm to 3mm;

The radius of the involute track-shaped semicircular coil from the outside to the inside is based on 5.5mm, 4.9mm, 4.3mm, 3.7mm, 3.1mm and 2.5mm, and changes positively within 0 to 0.1mm;

The transverse dimension of the involute racetrack-shaped coil is sequentially based on 6.5mm, 5.9mm, 5.3mm, 4.7mm, 4.1mm and 3.5mm from outside to inside, and changes positively within 0 to 0.1mm;

The diameter of the central hole of the PCB base is 2mm to 3mm, and copper is poured around the central hole;

The diameters of the three via holes connecting the detection coils on the front and back surfaces of the PCB substrate are 500um to 700um, and they are distributed in an obtuse triangle.
The three-dimensional detection device for dental implants based on a constant current source according to claim 1, characterized in that: the magnetic field distribution generated by the detection coil on the front side of the PCB substrate is concave; the frequency of the sinusoidal alternating current passed by the detection coil can be Adjustable between 230kHz and 240kHz, the peak voltage fluctuates between 400mV and 450mV during normal operation.
The three-dimensional detection device for dental implants based on a constant current source according to claim 1, wherein the detection sensor socket is from 0° to 90°, 90° to 180°, and 180° in the implant positioning device. Rotate within the range of 270°; the detection sensor socket is set in the socket of the implant positioning device through the plug-in end; that is, the detection sensor is in the control device from 0° to 90°, 90° to 180°, 180 Rotation within the range of ° to 270 °;

The insertion end of the detection sensor socket is a cylindrical structure, and a limit boss is set at the 0° position; the outer side of the insertion end is covered with a diamond-shaped shrapnel, and the shrapnel is fixed in the jack through the limit step on the inner wall of the jack, and the jack is also It includes positioning grooves for accommodating the four corners of the diamond-shaped shrapnel; the angle between the limiting steps is 90°;

The detection sensor is a hollow structure with built-in cables.
The three-dimensional detection device for dental implants based on a constant current source according to claim 1, wherein the state display control module is arranged at the bend of the implant positioning device, and the state display control module is divided into Eight areas, eight areas are equipped with two red and green LED lights; specifically include 0 to 5 display area and button 1, button 2; the circular 0 display area is set in the center of the circle; the periphery of the 0 display area is button 1 and button Two circular ring structures, the outermost ring structure is composed of 1 to 5 display areas.
The three-dimensional detection device for dental implants based on a constant current source according to claim 1, characterized in that:

The power supply is a battery, which is arranged in the battery compartment at the end of the implant positioning device to provide working power for the detection sensor and the implant positioning device;

When the battery voltage is close to the critical point, the constant voltage source module is under the control of the CPU, and the constant voltage module circuit starts; to ensure the normal clinical use of the device and reduce the inefficient working time of the device; when the battery voltage is lower than the working threshold After that, the host cannot be turned on, prompting to replace the battery;

The frequency conversion module includes three frequency gears, the high frequency gear is 8 to 12MHz, the intermediate frequency gear is 4 to 8MHz, and the low frequency gear is 0.1 to 4MHz; the inner wall of the implant positioning device is also inlaid with a layer of 300um metal copper mesh Shield.
The three-dimensional detection device for dental implants based on a constant current source according to claim 1, characterized in that:

The detection sensor length is 34mm to 36mm, the maximum width is 6mm, and the thickness is 1mm;

The front and back sides of the detection sensor are provided with helical metal coils, and the number of coil rings is 6; the material of the detection sensor is a printed circuit board, namely PCBI1505.
The three-dimensional detection and positioning method of dental implants based on a constant current source: turn on the instrument switch, and the detection sensor oscillates at the natural frequency. If the mandibular implant is detected, the detection sensor does not need to be rotated. If the maxillary implant is detected, the detection sensor is first rotated by 180°. Then gradually approach from the top to the vicinity of the gingiva where the implant is buried. During the approach process, the oscillation frequency of the detection sensor increases gradually, and the display on the instrument panel gradually increases. The light is on, and positioning marks are made from above at the same time; then the detection sensor is rotated 90° and 270° to detect the implant from the outside and inside of the gingiva, respectively, and mark the front and back of the gingiva, and finally accurately locate the burial with 3 mark points Implants in the gums.
The three-dimensional detection and positioning method for dental implants based on a constant current source according to claim 8, wherein the positioning method comprises the following steps:

Step 1. When the implant is not detected, the frequency f of the LC oscillation circuit is stable at 2.0 to 2.3 MHz, and the magnetic induction intensity B is stable at 0.245 to 0.250 mT;

Step 2, the relationship between the LC oscillation circuit frequency f (MHz) and the magnetic induction B (mT) when the implant is detected is: f=13.66/[1+(B/0.05) -0.71 ]-7.40;

Step 3. The relationship between the LC oscillation circuit frequency f (MHz) and the magnetic induction B (mT) when approaching the center of the implant is: f=-0.25/[1+(B/0.29) -26.82 ]+2.41;

Step 4. When the center of the implant is located, the frequency f of the LC oscillation circuit is stable at 2.5 to 2.6 MHz, and the magnetic induction B is stable at about 0.303 to 0.310 mT.
The three-dimensional detection and positioning method for dental implants based on a constant current source according to claim 9, wherein:

The LC oscillating circuit is composed of a coil and a capacitor of the detection sensor. When it is close to the implant in the gum and penetrates the 2.5mm-3mm thick gingiva, the inductance of the coil changes, and the frequency of the oscillating circuit changes with the The change, the transmission distance s (mm) and the frequency f (MHz) of the LC oscillator circuit satisfy:

s = 1.57e 0.05f +1.
The three-dimensional detection and positioning method for dental implants based on a constant current source according to claim 8, wherein the formula for calculating the magnetic induction of the involute track-shaped detection coil is:

Taking the front coil as the xoy plane, the coordinate origin is located at the center of the central hole, so the distribution of the magnetic field above the xoy plane on the central axis is obtained as:

On the central axis, the distribution of the magnetic field below the xoy plane is:

Finally, on the central axis, the distribution of the total magnetic field is:
The three-dimensional detection and positioning method for dental implants based on a constant current source according to claim 8, characterized in that: when the detection device rotates 0° for detection, the direction of the magnetic field is parallel to the direction of the gums and vertically downwards to detect the implant of the mandible;

When rotating 180° for detection, the direction of the magnetic field is parallel to the direction of the gums and vertically upwards to detect the implants in the upper jaw;

When rotating 90° to detect from the outside of the gingiva, the direction of the magnetic field is perpendicular to the gingiva and inward to detect the implant on the outside of the maxillary or mandibular gingiva;

When rotating 270° to detect from the inside of the gum, the direction of the magnetic field is perpendicular to the gum and outwards to detect implants inside the upper or lower gums.
The three-dimensional detection and positioning method for dental implants based on a constant current source according to claim 8, wherein the working steps of the buzzer and the display area are as follows:

Step 1, put a battery into the battery compartment of the implant positioning device, and then insert the detection sensor and the detection sensor socket into the front end of the implant positioning device as a whole;

Step 2, press button 2, the buzzer emits a short "beep" sound, each green light in the 0, 1, 2, 3, 4, 5 display area is on, and after 0.5 seconds, the green lights are all off; then the implant The positioning device enters the self-inspection state; if the self-inspection fails, the red lights in the 1, 2, 3, 4, and 5 display areas will glow in circles, that is, the five red lights will be on for 0.2 seconds each, and will automatically shut down after 1 second; If the self-test passes, the green lights in areas 0, 1, 2, 3, 4, and 5 are always on;

Step 3, after pressing the button 1, the system enters the treatment state, at this time, the green lights in the 0, 1, 2, 3, 4, 5 display areas are flashing, on and off for 0.5 seconds each, and the cycle is carried out; when the detection sensor enters the medium and weak When detecting the area, the green light and red light in the 0, 1, 2, 3, 4, 5 display area are all on, showing orange; when the detection sensor enters the strong detection area, the green light in the 0 area is on, and the buzzer sends out two A long "beep" sound indicates that the implant has been found; after marking, continue to look for the next implant.
The three-dimensional detection and positioning method for dental implants based on a constant current source according to claim 13, characterized in that in step 3, the following frequency conversion operation is also included:

Put the detection sensor deep into the oral cavity, rotate the detection sensor socket to make it easy to detect; press the treatment button, that is, press the button once; make the frequency gear at the lowest gear, and then move the detection sensor on the tooth surface, if the detection sensor has entered the implant At this time, the lights in the 1, 2, 3, 4, and 5 display areas are orange, that is, the red light and the green light are on at the same time; then continue to move, when the detection sensor is at the center of the implant, the green light in the 0 display area is on, and the other lights are on. No light; if the implant is not detected during the whole process, according to the selected gear, under the control of the CPU, after the frequency conversion processing of the frequency conversion module, the frequency gear is gradually adjusted from the middle frequency gear to the high frequency gear until the implant is detected .