KR20110074949A - A measuring device for osseo-integrated dental implant stability - Google Patents

Abstract

PURPOSE: A measuring device for osseo-integrated dental implant stability is provided to prevent a screw part of an implant from being damaged and to obtain precise date. CONSTITUTION: A measuring device for osseo-integrated dental implant stability is constituted as follows. A transducer is made of a homogeneous material and has a fixed size. A torque wrench uses in order to make bonding of a connection part of an inner screw and the transducer. A moving-picture camera confirms the location of a screen in a control box(1). A percussion pole body portion easily approaches the transducer by using a distance sensor and an angle sensor. A percussion bar strikes the body of the transducer with constant power.

Description

A measuring device for Osseo-Integrated Dental Implant stability

The present invention relates to an apparatus for measuring the stability of artificial teeth implanted in bone after implanting artificial teeth in bone.

Literature on the Measurement of Osteoadhesive Arterial Stability

Reference 1 US, 5518008, (Cucchiaro et. Al), May 21, 1996

Osstell ^™ mentor Clinical manual

Paper on Artificial Teeth Strength.

[Document 3] "Basic Study for Development of Implant Stability Evaluation Device", Bong Eun-sook, Jong-Kwon Kwon, Dental Research, Vol 56, No 1, 2004, pp 41-57.

After implanting the artificial tooth in the bone, there are only documents 1 and 2 mentioned above in the background art, and instruments and apparatuses that quantitatively indicate how stable and stable the osteoadhesive tooth is. The numbers shown by these two instruments are not related at all, and the measurement technique used by the two instruments is slightly different. In the method used in Document 1, as mentioned in Document 3, a physical shock (strike) is applied to the artificial tooth to measure the frequency at which the artificial tooth vibrates. The most commonly used method in the field of vibration metrology engineering (see paper 3) is a method of measuring the frequency of resonance inside an object by applying a wideband vibration shock. Since the frequency is measured by contacting the artificial tooth part, the vibration value of the contacting device causes the internal resonance frequency of the artificial tooth to change. Therefore, the exact value is not measured. The method used in Document 2 was developed by Austel Co., Ltd., in order to accurately measure the vibration value, the sensor part is placed close to the transducer, and the frequency is measured using a small microphone. When using a microphone, a lot of noise in the air is involved. The transducer used consists of very precise properties (magnetic). The principle is that the measuring device forms a constant magnetic field in the transducer. The transducer then bends to one side. After that, if the magnetic field is rapidly removed (measuring device), the curved transducer is restored to its original state and vibrates. The vibration then forms a frequency, the microphone acquires this frequency, and after the charge amplifier connected to the microphone amplifies the signal, it shows the most dominant frequency to the device. The problem with this device is that it is not easy to connect the transducer precisely and evenly to the artificial tooth. Too much force may destroy the state of adhesions or result in a change in the shape of the internal thread of the artificial tooth or a deformation of the transducer itself. If too weak, it will not vibrate correctly. In addition, since noise is scattered in the air (noise is easily added), a lot of noise is added, making it difficult to find an accurate natural frequency. In addition, the transducer is always bent to a certain degree so that it does not give a wideband impact, and furthermore, depending on the user, the distance between the measuring device and the transducer is different. In this case, the degree of bending of the transducer is different, so that even if the same artificial teeth are targeted, the measured frequency value is different.

Both of these patents use well-known basic methods (ie, warping or bending the object under the influence of a magnetic field).

The present invention is already placed in artificial teeth,

1. To connect the transducer with constant strength, use a torque wrench that automatically operates only with the specified force to mount and remove the transducer. In this case, since the connection strength of the artificial tooth and the transducer is always constant, there is no frequency variation by this connection.

2. For correct connection of the transducer, use a small digital camera to operate the instrument while checking the connection of the transducer in the artificial tooth.

3. In order to measure accurate parameters (frequency, damping factor, etc.), always strike a connected transducer in a constant direction, applying a constant force (broadband because it is a direct hit) and also the position of the transducer is unstable. To avoid this, the torque wrench holds the transducer up until immediately before the strike and then releases it when the strike is made.

4. As with "Ostel" products, when a frequency is acquired using a microphone, noise is included, so data is acquired directly using a sensor in contact with the transducer's surface.

If you use this device,

1. By using an automated precise torque wrench, the transducer is mounted or detached with a constant force, so that the internal thread of the implanted artificial tooth is not damaged.

2. Connect the transducer easily because you are working while checking the part connecting the transducer in real time.

3. The hitting data is stable because the hit is applied instantaneously, automatically, and with a constant force.

4. Since the data is obtained via a sensor connected to the surface of the transducer, there is no room for external noise.

Therefore, regardless of who uses the implanted artificial teeth, it is possible to acquire the data stably, and the methods are all automated, so the data acquisition is precise and very simple to use.

(rescue)

The device consists of two parts as a whole. It consists of a control box corresponding to (1) of Figure 1 and a measuring device connected thereto (referred to as percussion rod, 2 of FIG. 1). The control box is connected to your computer via USB. The tagin rod is directly connected to the control box and is able to send and receive various necessary signals and data with the control box. The various data collected by the control box from the percussion rod are transferred to the computer via a USB connection to the computer. The control box also receives external power.

As shown in Fig. 2, the control box includes one large screen (LED, 14), three light-emitting diodes (12, 13, 19), three switches (15, 16, 17), and two connection ports. (10,11). This screen serves to show the object to which the screw part of the transducer is facing through the camera installed near the inlet (211 in FIG. 4) connecting the transducer to the percussion rod body (No. 21 in FIG. 3). . To show the exact target position, always display a "+" on the screen's middle (Figure 18).

(12) and (13) of the control box indicate the distance from the position of the beginning (screw start) of the transducer coupled to the percussion rod body, to the beginning of the internal thread of the artificial tooth, the direction of insertion of the transducer and the artificial teeth The LED displays the slope (angle) between directions. That is, the distance indicating LED shows red when the distance is far, yellow when near, and green when near, and the angle indicating LED also plays a role. In other words, if the coupling angle is correct, it is displayed in green color. Along with the LEDs for this distance and angle, speakers can be added to represent the sound. That is, if the distance from the object is far away, the sound is slightly higher, and the closer it is, the lower bass sound is made. The same applies to angles. The location of the two LEDs is not critical and can be placed in a location that is comfortable for the user to see. In another embodiment, these two LEDs may be removed and this role may be shown at the top of the screen (14). The LED 19 serves to indicate “green”, otherwise “red” when the transducer is correctly inserted into the percussion rod body (described later).

The switch 15 is a switch for instructing the start of operation of the torque wrench to mount the transducer to the artificial tooth internal thread. After the transducer has been mounted on the artificial tooth internal screw and the switch 16 is activated, percussion begins. When the switch 17 is operated after the percussion is finished, the transducer rotates in the opposite direction as when the transducer connected to the internal screw of the artificial tooth is connected. Thus, the connected transducer is released.

The switches are not in the body of the percussion rod but in the control box. If the switch is in the percussion rod body, the percussion rod body may shake as soon as the user's hand touches the switch, but in the control box, the percussion rod is operated by another hand not holding the percussion rod shaft. The body does not shake.

2, 11 denotes a USB connecting to a computer, and 10 denotes a port connecting to a percussion rod. You may not have a USB connection to your computer. Instead, it is possible to exchange various data between the control box and the computer using the wireless Internet or using Bluetooth communication.

The inside of this control box (FIG. 5) is the same as that of a normal computer. However, there is no hard disk in the control box, and instead, the memory 311 is used as a flash memory whose information is not erased even if power is not supplied. This structure is the same as the industrial board which is used a lot in the industrialization field. Instead of this board, you can use specialized chips (chips with CPU, memory, and I / O). The main role of the control box is to process, store, and transfer the data received from the percussion rod. An additional role is to express various signals (video signals, signals received from distance and angle sensors) transmitted from the percussion rod to the display devices 313, 315, and 319 of the control box after some processing. The board also transmits signals such as "start" 316, "hit" 317, and "end" 318 to the percussion rod.

The outer structure of the percussion rod is shown in FIG. 3, which consists of a shaft 22 holding the percussion rod by hand and a percussion rod body 21 having various device sensors for measuring a signal in direct contact with an artificial tooth. This percussion rod is connected to the control box in a bundle (23) to receive power and signals. The percussion rod shaft consists of a flexible, hollow pipe. In other words, in order to easily approach the body of the percussion rod near the artificial tooth (implant), it is an empty hollow shaft that bends freely. This empty space contains the signal and power lines connected to the control box. 14 is an example of this flexible flexible shaft. This product, used in dentistry, is the tip of the suction. It's a plastic tube with a copper wire inside it. Once bent, it remains as it is. Flexible shafts consist of this type of pipe.

The percussion rod body receives power from the control box, and the signal wire is connected between the percussion rod body and the control box, with the image transmission line, the distance sensor line, the angle sensor line, and the percussion rod body. It consists of signal line for setting the intensity of 241) of Figure 6, limit value of torque wrench), and line that finally delivers the measured value after the striking rod is hit.

The appearance of the percussion rod body is shown in FIG. 4. The body is generally rounded when viewed from above or below, and the body itself is shape-independent. In the proper position (top view in FIG. 4), the switch 210 to be used is shown when securing the transducer to the bottom 214 of the percussion rod body.

The bottom view of FIG. 4 (the lower surface of the rod body) includes the camera lens 211, the sensor 212 for measuring the distance of the object, the sensor 213 for measuring the angle of the object, and the illumination (small, powerful). Light bulb 215). The light bulb illuminates the dark areas, helping the video camera to shoot every corner brightly.

The camera uses a digital camera. The resolution (3 million pixels or 5 million pixels) enough to be used for a mobile phone is sufficient, and distance measurement uses a laser or an ultrasonic sensor. Angle sensors also use sensors already on the market.

The transducer looks like FIG. 7, which looks like a screw with a normal cross head. That is, the screw 224 that exactly fits the inner screw bone (pitch) of the artificial tooth is at the bottom (this part is later joined to the artificial tooth inner thread part), and the striking rod 223 transmits an impact, and the upper edge part It consists of 221. A portion of the upper edge portion 221 whose groove is broken by "+" is engaged with the torque wrench (242 of FIG. 6, 233 of FIG. 8). It looks like a "+" screwdriver fits snugly into a regular bolt screw head. The size of this transducer is always constant. Also, the objects that make up the transducer consist of a uniform material with a uniform distribution (eg titanium or aluminum).

Figure 6 is a simplified illustration of the interior of the percussion rod body. Most power lines and signal lines are omitted here, and only important parts are drawn. It is composed of two three parts. Strike bar 241 for percussion, torque wrenches 233, 242, 261, 262, 255, 232 for fixing the transducer, and motors 252, 253 for driving the torque wrench.

 6 (277) is the same part as (214) of FIG.4, and is a round shape (ring) made of rubber-like material having a good elasticity, and serves to hold and fix the transducer, and at the moment of percussion Release what was just about to bite. This part also has the ring open when the switch on the top of FIG. 4 is pressed and closes when the switch is released.

The periphery of the percussion stick 241 is wrapped with an electromagnet (solenoid). That is, at the time of "hit", the striking rod always moves with a constant force by the constant magnetic field formed in the electromagnet.

8 assumes that the transducer 231 is fixed to the percussion rod body (indicated by dotted lines), and the transducer is fixed. At this time, the portion 233 is tightly bited to the "+" of the transducer, the sensor is connected. That is, a sensor for measuring acceleration or measuring frequency is always connected to "+" (that is, a portion in contact with the transducer, 233 of FIG. 11). This sensor is attached with a piezoelectric element or an acceleration sensor of MEMS type.

(Operation method)

(1) Fix the transducer to the percussion rod body.

The user pushes the switch (210 in FIG. 4) on the top of the percussion rod body. Then, the lower plate 214 of the body is opened. While pressing this switch, with the other hand, insert the transducer deep inside the open (214) under the percussion rod body, and then the head of the transducer touches the sensor inside the body (242 in FIG. 6). When touched correctly, the "19" light on the control box lights up. The transducer is firmly fixed to the body.

The transducer of Figure 7 is tightly sewn into the body, as shown in Figure 8. That is, 232 of FIG. 8 is the same as 232 of FIG. 6, and catches the head of the transducer. Then, the "+" crushed portion of the transducer is pinched at the ends of FIGS. 6 (242) and 8 (242). The screw of the "+" screwdriver becomes like a screwdriver.

(2) Place the transducer on the percussion rod body on the screw inside the artificial tooth.

In this way, the transducer, which is bitten by the percussion rod body, is approached by the user with the target artificial tooth. When the percussion rod body is close to the artificial tooth, the lights and cameras are automatically activated. Alternatively, the lights and the camera may be operated manually (in this case, an additional switch on the control box is required). The video taken by the camera of the tajinbong body is displayed on the screen of the control box in real time. The user then looks at this screen and, with the help of the LED indicating the distance and the LED indicating the angle, moves the percussion rod shaft and places the screw starting part of the transducer at the inlet of the artificial screw.

(3) Attach the transducer to the internal thread of the artificial tooth.

When the transducer is pressed against the inlet of the artificial tooth and the "start" switch of the control box is pressed, the drive motor of the torque wrench (252 in Figs. 8, 9 or 10) is operated and the screw of the transducer is connected to the artificial tooth. It will be wound inside. At this time, when the force that resists the coupling between the artificial tooth and the screw of the transducer reaches the force (torque) already set, the sensor senses and gives a stop command to the motor to stop the motor. That is, the artificial tooth screw and the transducer are always combined with a constant connection strength.

The connection between the torque wrench (body of 233, 242, 261, etc. of FIG. 6) and the driving motor is connected as shown in FIG. 9, the gears 253 and 254 are in direct contact between the motor and the torque wrench, so that the rotational force of the motor is transmitted directly to the torque wrench.

(4) hitting the transducer.

When the screw of the transducer is wound around the artificial tooth screw, the next step is to hit the transducer with the striking rod. This strike is activated by the "percussion" switch in the control box, or automatically after the transducer is fully connected to the artificial tooth (Example 3).

When the striking command is started, the striking rod (241 of FIG. 11, or 241 of FIG. 6) strikes the percussion part of the transducer (223 of FIG. 7) with a constant force by an electromagnet around the striking rod. do.

However, just before hitting (i.e., just before hitting the transducer against the transducer), all the parts holding the transducer open. That is, the part 277 of FIG. 6 also puts the transducer which was held, and the body of the transducer which also held the part 232 of FIG. 6 and FIG.

 In addition, when viewed from the top of the torque wrench, a part of winding or releasing the "+" of the transducer (261 in FIG. 13) is mechanically separated from the torque wrench (outside 262 in FIG. 13). That is, when the coils are joined together with a rubber-like rubber with good frictional force, the force is transmitted to the "+" driver as it is wound or unwound (as shown in Fig. 12). Is separated (FIG. 13). Thus, this part is also separated from the sensor.

Therefore, at the moment the striking bar hits the transducer, only the transducer is connected to the sensor ("+" part), through which the sensor acquires data relating to vibration (mixed frequency, damping value), The acquired data is transferred to the control box.

At the end of this process, the part that was briefly open for the blow (262 in FIG. 13, 232 in FIG. 6, and 277 in 6) again holds the transducer firmly.

(5) Removing the transducer from the artificial tooth.

Next, the transducer is released by the torque wrench by means of the "end" switch of the control box. That is, the drive motor rotates in reverse to separate the transducer from the artificial tooth.

(6) Disconnect the transducer from the percussion rod body.

When the transducer is completely separated from the artificial tooth, the doctor pulls the entire percussion rod out of the patient's mouth. Next, while pressing the switch 210 on the upper surface of the percussion rod body, with the other hand, the transducer is pulled out of the body.

(Meaning and Processing of Acquired Data)

The frequency measured after the striking rod impacts: (1) the frequency of adjacent bones (related to bone density and bone structure), (2) the adhesion of artificial and adjacent bones, (3) the natural frequency of the artificial teeth itself, ( 4) the natural frequency of the transducer, and (5) the mixed frequency, which includes the coupling between the transducer and the artificial tooth. However, since the artificial teeth and the transducer have a constant object (the size and the kind of the substance are fixed), and the internal resonance frequency is always fixed, it can be seen, and the connection between the artificial teeth and the transducer is always constant (the constant torque by the torque wrench). (I.e. 3, 4 and 5 above are fixed values), the variables remain only the degree of adhesion between the artificial teeth and the surrounding bone (stability) and the strength of the surrounding bone (close to the bone density). These two data represent artificial tooth stability.

The mixing frequency that is captured is represented by Equation 1. This equation represents the relationship between the measured signal value (Amplitude) M (t) and time at a certain time t. In Equation 1, the magnitude of each component is represented by a _i , and each frequency is represented by f _i . This equation is transformed using a Fourier transform, resulting in a relationship between power and frequency. That is, the frequency on the x axis and the intensity of those frequencies on the y axis. For example, if five frequencies are mixed, high values on the y-axis appear in five positions on the x-axis. This means that there are five components of frequency (frequency values are on the x-axis). Thus, very accurately, each element value can be obtained. Thus, all five of the above factors can be obtained. This calculation is done on the control box, or on the computer while transferring from the control box to the computer.

In other words, the mixed frequency is a variable according to the degree of connection between the artificial tooth and the surrounding bone, the internal frequency of the constant artificial tooth, the internal frequency of the constant transducer always, and the frequency of the combination of the constant transducer and the artificial tooth.

(Example 2)

The lamps (12) and (13) of the control box, i.e., the distance and the angle, may instead display this role at the top of the screen (No. 14).

Example 3

The three switches, the "start" switch 15, the "percussion" switch 16, and the "ends" may be replaced by one switch. In other words, the steps of installing the transducer on the artificial tooth, tapping on the transducer, and removing the transducer occur sequentially, so that if one switch is used, the first step is started. When you are finished, you can use the next step to start automatically.

Example 4

Another example of the connection method between the torque wrench (233, 242 bodies in FIG. 6) and the drive motor is FIG. 10. 10, the rotational force of the motor 252 is transmitted to the torque wrench 255 through the chain (256 in FIG. 10).

The stability of the artificial teeth can be measured very consistently and precisely.

1: Appearance method of the device and the computer. The instrument consists of a shaft and percussion rod body.

2: Appearance of the control box. It consists of various switches, LEDs, screens, and connection ports.

3: Example of percussion rod (body and flexible shaft). The handle of the percussion rod consists of a flexible (keep bent) material or a spring.

4: Outline of percussion rod body. Conceptual model diagram of percussion rod body that plays a key role.

5 is a conceptual diagram of the inside of the control box. It forms the structure of controller that is used in general industry.

Fig. 6: An internal conceptual view of the percussion rod body. The power line and signal line are not shown, but show the positional relationship of the transducer, blow bar, torque wrench and driving motor.

7: Configuration (shape) of the transducer used. It is screwed to fit into an artificial tooth.

8: The transducer is engaged with the torque wrench. Tightly coupled.

9: Model of torque wrench and drive motor connected directly to gear.

10 is a model diagram in which a torque wrench and a driving motor are connected through a chain. Another embodiment of FIG. 9.

11: Relevance of transducer and percussion rod. The striking rod strikes the body of the transducer.

12; Conceptual diagram of transducer and torque wrench attached. The transducer is firmly attached to the torque wrench when connecting or disconnecting the transducer.

13: Conceptual view of the state in which the transducer and the torque wrench are separated. The transducer is separated from the torque wrench just before and during the striking of the transducer.

14: Another example of a flexible shaft. This product is a suction conduit that sucks water from the patient's mouth at the dentist. It's a plastic tube with a copper wire inside it. Once bent, it remains as it is.

Claims (6)

In order to accurately measure the joint strength (stability) between the artificial tooth and the surrounding bone, (a) using a transducer of uniform material and of constant size, (b) using an automated torque wrench (and minimizing the deformation of the internal teeth of the artificial teeth), in order to ensure a constant adhesion between the artificial connections (internal screws) and the connections of the transducers; (c) To make this connection easier, install a video camera on the percussion rod body, locate the position on the screen and access it from the control box, (d) In addition, the distance sensor and the angle sensor are auxiliaryly installed on the percussion rod body to allow the operator to easily access the transducer, (e) always strike with constant force when the rod hits the body of the transducer, (f) a "+" driver connected to the head of the transducer with sensors for acquiring frequency, damping factor and other data; (g) Immediately before striking, in order to ensure that this sensor is not subject to any external noise other than transducers, all external connections except the "+" driver must be disconnected, (h) automatically and safely disconnecting the transducer from the electric motor when the transducer is detached from the artificial tooth; The whole process and how and how to achieve it In order to implement claim 1, the process of connecting the transducer to the artificial tooth, hitting the transducer, and separating the transducer from the artificial tooth with a single operation switch. One or three switches for implementing claim 1 located in a control box. Use flexible material (or spring type) for the shaft of the percussion bar. In this case, the perforated rod body can be easily placed in a desired position between the narrow and complicated teeth and the artificial teeth, or between the artificial teeth in the oral cavity. Using wireless internet or Bluetooth communication to exchange data between control box and computer. The vibration frequency obtained by this method is analyzed to determine (1) the frequency of adjacent bones (related to bone density and bone structure), (2) the degree of adhesion between the artificial and adjacent bones (stability), and (3) the strength of the material forming the artificial teeth. To measure.

Images