JP2003519507A - Dental treatment method and apparatus utilizing free liquid jet - Google Patents

Abstract

(57) Abstract: A dental treatment method and apparatus for separating substances to be removed in various dental treatments at the boundary of healthy bone tissue, or in some cases, for thinning healthy bone tissue. According to the present invention, a high-pressure liquid is discharged in the form of a high-concentration free liquid jet having a high kinetic energy to the surface of a tooth to be treated through a nozzle attached to the end of a dental pretreatment dental treatment hand tool, and the liquid is discharged for treatment. Not only start and stop, but also gas pressure adjustment of liquid pressure. In an apparatus for performing the method according to the invention, the processing means of the hand tool (5) comprises a nozzle (6) suitable for emitting a high-pressure liquid jet, said nozzle (6) being controlled by an adjustable pressure regulator. The hydraulic supply unit (2) is supplied with a hydraulic pump (17) driven by the hydraulic supply unit (2), and is driven by the drive unit. And a hydraulic pump (17) connected to the liquid container (3), and a gas pressure control type three-way hydraulic valve (37) is arranged in the passage of the hydraulic pump (17) led to the nozzle (6). In the gas pressure control circuit, a switch for detecting the raising of the hand tool (5) and a tool position sensing valve (39) operated by a foot switch (40) are connected in series. /Fig.1/

Description

Detailed Description of the Invention

The present invention relates to a method of dental treatment that uses a free liquid jet to separate the material to be removed at the boundary of healthy bone tissue or, in some cases, to thin healthy bone tissue during dental treatment. Regarding the device.

BACKGROUND OF THE INVENTION As the most frequently performed dental treatment, preparation of a filling material for the treatment of dental caries, removal of soft tissue from a tooth groove in the case of root treatment, or adhesion to tooth enamel. For example, cleaning substances. In each of these cases, the material to be removed must be separated at the boundaries of healthy bone tissue.

A large number of methods and preparation devices are already known for this purpose. Most commonly used are mechanical devices and tools, which are usually driven by turbines or electric motors that blow a compressed gas. The basic problem with mechanical devices is that they do not allow accurate separation of healthy and pathological tissue, and thus the relative probability of losing healthy tissue is relatively high. When rotating mechanical devices, cooling is essential to avoid tissue damage due to frictional heat, which results in complex work and is not very cost effective.

Furthermore, methods of using acoustic waves and ultrasonic waves for pretreatment of teeth are also known, in which case the pretreatment of teeth is performed by applying sound waves of appropriate frequency, and water is used for rinsing liquid or It is used only as a medium for transmitting shock waves. This method has the drawback of being relatively time consuming and costly.

Laser beam treatment is also known in dentistry and is mainly used for cutting soft tissue, but when carbon-containing organic tissue is carbonized, it causes discoloration, and when the energy of the laser beam is increased, the treated surface is treated. Not only can it not be used for the separation of healthy and pathological tissue due to the poor quality of the tooth, but also the equipment suitable for cutting the tooth enamel is very expensive.

(Object of the Invention) The problem to be solved by the present invention is to provide a method and apparatus for dental treatment for separating healthy tissue and pathological tissue while maintaining high accuracy and reliability, and At the same time, making it easier for the healthy tissue of the teeth, namely the tooth enamel, dentin, and cementum, to be cut without causing any harmful side effects, which the dentist does with conventional pretreatment methods. Commonly used pretreatment techniques can be used.

The present invention is well suited for efficient, controlled destruction or shaping of solid tooth material while a free, dense liquid jet of sufficient energy directly cools the surface to be treated. It is based on the recognition that.

SUMMARY OF THE INVENTION On the basis of the above recognition, a high pressure kinetic energy in the form of a high density free liquid jet under high pressure is applied to the surface of the tooth to be treated through a nozzle mounted at the end of the dental treatment tooth preparation device. This problem is solved by a method of ejecting a liquid, starting and stopping the ejection of the liquid, and preparing the teeth by adjusting the gas pressure of the liquid pressure.

[0009]   According to the invention, the treatment liquid is preferably distilled water.

Also, this means that according to the invention the pressure of the discharged liquid is between 60 and 150 MPa.
It is preferable when it is adjusted within the range.

In order to implement the method according to the invention, the dental treatment device comprises a hand tool including processing means suitable for preparatory treatment, said hand tool sensing the foot switch and the hand tool being raised. By operating the sensing switch at the same time, it can be operated by connecting to the energy source. According to the present invention, for the processing means of the hand tool,
It is characteristic that this is composed of a nozzle capable of ejecting a high-density high-pressure liquid jet. The energy source for delivering liquid to the nozzle is a hydraulic supply unit controlled by an adjustable pressure regulator.

The hydraulic pressure supply unit is operated by a drive unit and includes a hydraulic pressure pump connected to the liquid container, and a gas pressure control type three-way hydraulic valve is inserted into a supply line of the hydraulic pressure pump guided to a nozzle. . Further, a tool position sensing valve operated by a sensing switch that detects a rise of a hand tool and a foot valve operated by a foot switch are connected in series by a gas pressure control circuit of a three-way hydraulic valve.

According to the invention, this is the case in the case of a gas motor in which the drive unit of the hydraulic pump is connected to a gas pressure supply unit which also supplies compressed gas via the gas pressure conduit to the gas pressure control element of the hydraulic system. Is preferred.

In another preferred embodiment of the invention, the adjustable pressure regulator controlling the hydraulic supply unit is arranged on the console and is suitable for continuously adjusting the control pressure from 0 to a maximum value. A gas pressure regulator, wherein the gas pressure regulator includes a differential piston configured of a gas pressure and a hydraulic piston via a gas pressure conduit, and a combined hydraulic control including a stroke position sensing valve provided in the differential piston. Connected to the unit.

According to a preferred variant of this embodiment, one of the stroke position sensing valves of the hydraulic control unit is connected to a level valve which prevents the control pressure from rising if the liquid level falls below a minimum value. The valve is controlled by a float that senses the actual liquid level.

Finally, for safe operation of the device, a working pressure limiting valve that temporarily opens towards the return conduit in case of a certain excess of hydraulic fluid pressure and a certain excess of maximum hydraulic fluid pressure. It is expedient to insert a pressure limiting safety valve with a rupture disc which is activated in the event of a break between the hydraulic delivery conduit of the hydraulic supply unit and the return conduit leading to the liquid container.

The invention will be described in more detail on the basis of preferred embodiments with reference to the accompanying drawings, in which FIG. 1 is a schematic diagram of a possible arrangement of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS As can be seen in the schematic diagram shown in FIG. 1, the device according to the invention comprises a compressed gas supply unit 1 which delivers the energy necessary for the operation and control of the device and a pretreatment treatment. A hydraulic pressure supply unit 2 that secures the necessary pressure energy of the liquid, a liquid container 3 connected to the hydraulic pressure supply unit 2, a control element and a safety element operated from an operation console 4,
A nozzle 6 as a processing means is basically composed of a hand tool 5 for dental treatment and a conduit connected to each other, and a nozzle 6 as a processing means is used for converting pressure energy into kinetic energy for ejecting a concentrated liquid jet. Incorporated in 5.

The compressed gas supply unit 1 is composed of an electric motor 7 and a compressor 8,
An air filter 9 is arranged on the inlet side of the compressor 8, and a back pressure valve 10 for preventing the backflow of compressed gas is arranged on the outlet side. The compressor 8 is connected via a back pressure valve 10 to a compressed gas tank 11 that stores compressed gas generated by the compressor and damps pressure fluctuations in the system. Furthermore, the compressor 8 is also connected to a pressure switch 12 for adjusting the operating state of the compressed gas supply unit 1 according to the compressed gas p _k , so that the pressure switch 12 starts the compressor 8 with the adjusted lower value p _kmin. Then, the compressor 8 is stopped at the adjusted upper value p _kmax .

After the compressor 8, a gas pressure conduit that can be decompressed via an exhaust valve 13 branches into two conduits, an actuation branch and a control branch.

The gas pressure conduit 14 forming the working branch pipe is intermittently operated to the hydraulic pressure supply unit 2 including the gas motor 16 and the hydraulic pump 17, and the compressed gas is supplied via the bistable three-way valve 15. The feed pressure can be adjusted by the pressure adjusting valve 19 and can be read from the manometer 19. The adjusted compressed gas supply pressure value is such that the maximum value of the hydraulic pressure generated by the hydraulic pump 17 becomes equal to the pressure allowed by the hydraulic system.

A control circuit for controlling the hydraulic system is connected to a gas pressure conduit 20 representing a control branch, the pressure of which is adjusted to a maximum pressure (p _{vm ax} ) required in the control conduit by a pressure regulating valve 21. It can be adjusted and this pressure can be checked with the manometer 22.

The operating state of the hydraulic pressure supply unit 2 and the operating pressure of the hydraulic system are determined by the combined hydraulic pressure control unit 23. This combined hydraulic pressure control unit 23,
It consists of a differential piston formed by a pneumatic piston 25 and a hydraulic piston 26 mounted on a common piston rod 24, and an actuating means 27 which moves with the piston rod 24. The surface A ₁ of the pneumatic piston 25 is constantly filled with the control pressure p _v adjusted by the pressure adjusting valve 28 arranged on the console 4.
The value of the control pressure can vary between a maximum control pressure p _{vm ax} adjusted by the pressure regulating valve 21 from zero _{(0 <p v <p vmax} ). In a hydraulic system, the hydraulic pressure, which is proportional to the control pressure p _v , is much greater than A ₁ via the piston rod 24 as a result of the force (F = A ₁ × p _v ) being applied to the hydraulic piston 26. Occurs on a small surface A ₂ (
p _h = (A ₁ / A ₂ × p _v )). Actuating means 27 moving with piston rod 24
Are two stroke position detection valves 29, 3 connected to both sides of the bistable three-way valve 15.
It is in contact with 0. The upper stroke position detection valve 29 is connected to the gas pressure conduit 20, and the lower stroke position detection valve 30 detects the liquid level in the liquid container 3.
It is connected in series to the liquid level valve 32 operated by 1.

In front of the hydraulic pump 17 of the hydraulic pressure supply unit 2, the liquid filter 34 is installed in the hydraulic suction conduit 33 connecting the hydraulic pump 17 and the liquid container 3, and the hydraulic pump 1
After 7, a back pressure valve 36 is arranged in the discharge pipe 35 leading to the hand tool 5, said back pressure valve 36 being provided with a fluid pressure when the hydraulic pressure supply unit 2 is deactivated or during the suction time of the hydraulic pump 17. Prevents pressure drop from backflow.

On the way to the hand tool 5, the flow of liquid is regulated by a three-way hydraulic valve 37, which is controlled by compressed gas and is installed in the hydraulic pressure delivery conduit 35, and the hydraulic valve 37 is closed in its basic position, Hand tool 5 with tool holder 38 and foot valve 40
Is connected in series to a pneumatic conduit 20 forming a control branch through a tool position sensing valve 39 that detects the lifting of the.

To prevent the nozzle 6 from becoming clogged, the microfilter 4 as well as the back pressure valve 42 are incorporated into the hand tool 5, which allows the contaminated liquid to flow back into the system after use of the hand tool 5. I try not to cause aspiration. The hand tool 5 is connected via a flexible tube 43 to a three-way hydraulic valve 37 that controls the supply of high-pressure fluid, said hydraulic valve 37 being in its basic position, connecting the flexible tube 43 of the hand tool 5 to a hydraulic backflow conduit. It is connected to the liquid container 3 via 44.

To increase the safety of the hydraulic system, two pressure limiting valves 4 connected in parallel
6, 47 are incorporated into a backflow conduit 45 branching from the hydraulic delivery conduit 35 and leading to the liquid container 3. The operating pressure limiting valve 46 is operatively connected to the pressure regulating valve 28 via a pneumatic conduit 48, while the pressure limiting valve 47 is suitably a rupture disc.

[0028]   The current operating pressure of the hydraulic system can be read from the manometer 49.

Operation of the device according to the invention The operation of the device according to the invention is as follows. Compressor 8 of compressed gas supply unit 1 controlled by pressure switch 12
The pneumatic system is put under pressure by activating. Energy is supplied to the gas motor 16 of the hydraulic pressure supply unit 2 via the gas pressure conduit 14, which causes the gas motor 16 to deliver a therapeutic liquid of appropriate pressure to the hand tool 5.
To drive. The hydraulic pump 17 sends the liquid sucked from the liquid container 3 through the liquid filter 34 through the hydraulic pressure delivery conduit 35 to the nozzle 6 of the hand tool 5, which meets the conditions for operating the hand tool 5. Until it is blocked by the closed position of the three-way hydraulic valve 37.

Therefore, in order to operate the hand tool 5, the three-way hydraulic valve 37 must be operated. One of the conditions for this is that the foot valve 40 must be switched by stepping on the foot switch at the same time that the tool position sensing valve 39 is switched by lifting the hand tool 5 from the tool holder 38. Is. In this way, compressed gas can reach from the pneumatic conduit 20 through the foot valve 40 and the tool position sensing valve 39 to the three-way hydraulic valve 37, which causes the valve to switch to the operating state, ie the three-way hydraulic valve. 37 allows a highly pressurized treatment liquid, suitably distilled water, to flow through the hand tool 5.

The dentist can use the hand tool 5 as usual as a dental drill, where only the drill is replaced by a dense liquid jet. Starting and stopping of the hand tool 5 is accomplished in a known manner by actuating the foot valve 40 in any suitable manner. By reducing the possibility of accidental manipulation, both the dentist and the patient are safe. This is done because the combined condition for switching the three-way hydraulic valve 37 to the actuated state, thereby triggering the liquid flow, switches the tool position sensing valve 39 by lifting the hand tool 5 from the tool holder 38. At the same time, the foot valve 40 must be operated.

As described above, the operating state of the hydraulic pressure supply unit 2 and the operating pressure readable by the manometer 49 are determined by the combined hydraulic pressure control unit 23. The hydraulic fluid pressure required for the treatment for removing the soft substance is 60 to 70 MPa, but it is usually in the range of 120 to 150 MPa for peeling the enamel. The hydraulic fluid pressure adjustable by the pressure regulating valve 28 arranged on the console 4 acts on the surface A ₁ of the pneumatic piston 25 of the hydraulic control unit 23 via the pneumatic conduit 48,
It occurs via the piston rod 24 on the smaller surface A ₂ of the hydraulic piston 26, the working pressure of which is proportional to the control pressure p _v . As described above, during the adjustment, the actuating means 27 moving together with the piston rod 24 has the two stroke position detecting valves 29.
, 30 together. When the volume of therapeutic liquid is reduced as a result of the hydraulic system flowing out, the actuating means 27 approaching the lower stroke position actuate or switch the stroke position detection valve 29 before reaching its end position, whereby The bistable three-way valve 15 is at a position where compressed gas can flow to the gas motor 16, that is, the hydraulic pressure supply unit 2 starts to operate.

Since the amount of liquid sent by the hydraulic pump 17 is larger than the maximum usable value,
By storing the difference between the two quantities in the combined hydraulic control unit 23, the differential piston and at the same time the actuating means 27 move towards the upper end position, thereby increasing the capacity of the hydraulic system. Before the upper end position is reached, the actuating means 27 actuates the stroke position detection valve 30 to adjust the bistable three-way valve 15, so that the bistable three-way valve 15 closes the gas pressure conduit 14 to the gas motor 16. Ventilate the open conduit section. Therefore, the hydraulic control unit 23, as a flexible element, changes the capacity of the possible hydraulic system and keeps the hydraulic pressure constant irrespective of the instantaneous operating state of the hydraulic supply unit 2. , Also functions as a hydraulic accumulator.

As described above, the lower stroke position detection valve 29 of the hydraulic control unit 23 is
The liquid level valve 32 provided in the liquid container 3 is connected in series. When the liquid level of the liquid container 3 becomes lower than the adjusted lower limit, the liquid level valve 32 operated by the float 31
By separating the duct portion leading to the lower stroke position detection valve 29 to ventilate the air, and by switching the stroke position detection valve 29, the three-way valve 15 is in a switching position that prevents the hydraulic pressure supply unit 2 from starting.

The safety of the hydraulic system is ensured by the pressure limiting valves 46, 47. In the case of a malfunction of the combined hydraulic pressure control unit 23, the operating pressure limiting valve 46 causes the backflow conduit 4 to
Via 5 the liquid is temporarily discharged from the high-pressure volume into the liquid container 3 at a pressure (p _h + Δ _p ) which is slightly higher than the hydraulic actuation pressure p _h , whereby a further pressure increase is prevented.

The pressure limiting safety valve 47 breaks through a rupture disc incorporated in the pressure limiting safety valve 47 in case of occasional failure of the pressure limiting valve 46, so that the pressure limiting safety valve 47 is slightly higher than the maximum hydraulic fluid pressure p _{hm ax} (p It becomes the operation state at _hmax + Δ _p ). In this case, a short circuit is created between the high-pressure space and the backflow conduit 45, and the device cannot be used until the obstacle is removed.

The device according to the invention makes it possible to remove a great number of dental treatments, in particular carious enamel, dentin, cementitious, selective tissue-protecting, calcifications adhering to the tooth surface. It can be optimally used for removing white moss, separating and removing soft tissue of pulp cavity and predentin, and expanding or pretreating root groove.

The device according to the invention has numerous advantages over conventional dental preparation devices. 1) Pretreatment of healthy tooth tissue, ie enamel, dentin, cementum, all with biologically inert, and therefore pretreated ideal liquid, distilled water jets with adjustable pressure and radius. can do. 2) By selecting an appropriate water pressure for pretreatment depending on the hardness of the tooth tissue to be treated, only the pathological tissue is removed by the water jet, so that carious tissue and healthy tissue can be reliably ensured. Can be separated. As a result, pretreatment can be performed without loss of healthy tissue. 3) The unevenness of the pathological site at the boundary with the healthy tissue can be smoothed by simply increasing the pressure. 4) Pretreatment The construction of the hand tool that ejects the jet of water utilizes conventional pretreatment techniques applied to possible dental drills. 5) In addition to accuracy and safe and user-friendly properties that protect the patient, the device according to the invention can be manufactured at a considerably low cost.

[Brief description of drawings]

[Figure 1]   FIG. 3 is a schematic diagram of a possible sequence of the invention.

[Explanation of symbols]

1 compressed gas supply unit (pneumatic supply unit) 2 hydraulic supply unit (liquid) 3 liquid container (liquid container) 4 control desk (control desk) 5 hand tool (motor) z (no) nozzle 6 electromotor 8 compressor 9 air filter 10 back-pressure valve 11 compressed gas reservoir 12 pressure switch 13 pressure switch exhaust valve 13 pressure switch (pressure switch 13) Conduit (actuates branch) (pneumatic c nduit (
Actuating branch) 15 Bistable three-way valve 16 Pneumatic motor 17 Hydraulic pump 20 Pressure regulating valve (pressure regulating valve) 20 Control branching (pneumatic conduit (
Controlling branch) 21 Pressure regulating valve 22 Manometer 23 (combination) Hydraulic pressure control unit ((combined) hydra)
Ulic control unit 24 Piston rod 25 Pneumatic piston 26 Hydraulic piston 27 Actuating strokes 28 Pressure regulating valve side Position detection valve (lower) stroke po
position detecting valve 30 (upper) stroke position detection valve (upper) stroke po
Situation detecting valve 31 Float 32 Liquid level valve 33 Hydraulic suction conduit
) 34 liquid filter 35 hydraulic delivery conduit
t) 36 back-pressure valve 37 three-way hydraulic valve 38 tool holder 39 tool position sensing v
ave 40 foot valve 41 microfilter 42 back-pressure valve 43 flexible tube 44 (hydraulic) flow-back flow
onduty) 45 flow-back conduit 46 working pressure limiting valve (working pressure limiting valve)
valve) 47 pressure limiting safety valve (pressure limiting safety)
valve) 48 gas pressure conduit (pneumatic conduit) 49 manometer (manometer)

─────────────────────────────────────────────────── ─── Continued front page    (81) Designated countries EP (AT, BE, CH, CY, DE, DK, ES, FI, FR, GB, GR, IE, I T, LU, MC, NL, PT, SE), OA (BF, BJ , CF, CG, CI, CM, GA, GN, GW, ML, MR, NE, SN, TD, TG), AP (GH, GM, K E, LS, MW, SD, SL, SZ, UG, ZW), E A (AM, AZ, BY, KG, KZ, MD, RU, TJ , TM), AL, AM, AT, AU, AZ, BA, BB , BG, BR, BY, CA, CH, CN, CU, CZ, DE, DK, EE, ES, FI, GB, GE, GH, G M, HR, HU, ID, IL, IS, JP, KE, KG , KP, KR, KZ, LC, LK, LR, LS, LT, LU, LV, MD, MG, MK, MN, MW, MX, N O, NZ, PL, PT, RO, RU, SD, SE, SG , SI, SK, SL, TJ, TM, TR, TT, UA, UG, US, UZ, VN, YU [Continued summary] .Tool position sensing valve actuated by switch (40) (39) is connected in series. /Fig.1/

Claims (8)

[Claims] 1. A dental treatment method for separating, or in some cases, shaving, healthy bone tissue to be removed in the treatment of various teeth at the boundary of healthy bone tissue. Pretreatment Dental care Through a nozzle attached to the end of a hand tool, high pressure liquid in the form of a high kinetic energy dense free liquid jet is ejected to the surface of the tooth to be treated, for treatment the start and stop of liquid ejection A dental treatment method characterized in that not only liquid pressure but also gas pressure is adjusted. 2. The method according to claim 1, wherein distilled water is used as the therapeutic liquid. 3. The method according to claim 1, wherein the hydraulic fluid pressure is adjusted in the range of 60 to 120 MPa. 4. A dental hand tool which separates the substances to be removed in the treatment of various teeth at the boundary of healthy bone tissue, or in some cases by means of a dental hand tool with suitable treatment means suitable for pretreatment treatment. A dental treatment device for shaving bone tissue, wherein the hand tool can be operatively connected to an energy source by the simultaneous operation of a foot switch and a switch for detecting when the hand tool is raised. The treatment means of (5) comprises a nozzle (6) suitable for ejecting a high pressure liquid jet,
The nozzle (6) is supplied by a hydraulic pressure supply unit (2) as an energy source controlled by an adjustable pressure regulator, the hydraulic pressure supply unit (2) being driven by a drive unit and a liquid container (3). Is provided with a hydraulic pump (17), and a gas pressure control type three-way hydraulic valve (37) is arranged in the passage of the hydraulic pump (17) leading to the nozzle (6). Foot switch (40)
A dental treatment device, characterized in that a hand position sensor (5) and a tool position sensing valve (39) operated by a switch for detecting that the hand tool (5) are lifted are connected in series. 5. The drive unit of the hydraulic pump (17) is a gas pressure supply unit (
A gas motor (16) coupled to 1), characterized in that the gas pressure supply unit (1) also supplies compressed air to the gas pressure control element of the hydraulic system of the device through the gas pressure conduit (14). The device according to claim 4. 6. An adjustable pressure regulator for controlling the hydraulic supply unit (2),
0 and maximum value (p_vmax) And the control pressure (p _v ) Is adjustable, the gas pressure regulator (28),
28) is a pneumatic piston (25) and a hydraulic piston via a pneumatic conduit (48)
A differential piston formed by (26) and a strike provided on the differential piston.
In the combined hydraulic control unit (23) equipped with the roque position sensing valves (29 and 30)
Device according to claim 4 or 5, characterized in that it is connected. 7. A stroke position detection valve (29) of a hydraulic control unit (23)
30) one of which is a liquid level valve (32) which prevents an increase in control pressure when the liquid level decreases below its minimum value which is controlled by a float (31) which detects the liquid level in the liquid container (3). 7. The device according to claim 6, wherein the device is connected to. 8. A working pressure limiting valve (4) which opens temporarily towards a return conduit (45) to a liquid container (3) when the working hydraulic pressure ( _ph ) exceeds a predetermined value to a specified range.
6) and a pressure limiting safety valve (47) with a rupture disc which is activated when the regulated maximum working hydraulic pressure (p _hmax ) is exceeded, the hydraulic delivery conduit (35) of the hydraulic supply unit (2) Device according to any one of claims 4 to 7, characterized in that it is provided between the and the return conduit (45).