WO2000071049A1

WO2000071049A1 - Method and device used in dental medicine to carry out a treatment using a free liquid jet spray

Info

Publication number: WO2000071049A1
Application number: PCT/HU1999/000041
Authority: WO
Inventors: László BACSKÓ; Gábor VÁRBÍRÓ
Original assignee: Bacsko Laszlo; Varbiro Gabor
Priority date: 1999-05-21
Filing date: 1999-05-21
Publication date: 2000-11-30
Also published as: JP2003519507A; AU3949599A; EP1182983A1

Abstract

The invention relates to dental method and to a device for separating different materials to be removed during dental treatment conducted at the boundary of healthy bone tissue or, optionally, to abrade the healthy bone tissue. According to the invention, a highly-pressurized liquid provided in the form of a concentrated free liquid jet spray is directed with a large amount of kinetic energy onto the tooth surface to be treated via a nozzle mounted on the end of a dental tool. The working element of the hand tool (5) is formed by a nozzle (6) which is suited for discharging a concentrated highly-pressurized liquid jet spray and which is supplied with liquid by a hydraulic supply unit (2). Said hydraulic supply unit serves as an energy source and is controlled by an adjustable pressure controller (28). In addition, the hydraulic supply unit (2) contains a hydraulic pump (17) which is actuated by a drive unit and which is connected to a liquid container (3). A pneumatically controlled three-way valve (37) is placed in the supply line of said pump (17) which leads to the nozzle (6). A tool sensing element valve (39), said tool sensing element valve being actuated by a switching element that detects the lifting of the hand tool (5), as well as a foot valve (40) which is actuated by a foot switch are connected in series in the pneumatic control circuit of said three-way valve.

Description

METHOD AND DEVICE FOR DENTIST

TREATMENT WITH A FREE LIQUID JET

The invention relates to a method and a device for separating

of various materials to be removed during the dental treatment at the border of the healthy bone tissue or against

also for the abrasion of the healthy bone tissue

During the most common dental treatments such as the

Preparation of rotten teeth for sealing, in the case of a tooth root

treatment when removing the soft tissue located in the root canal

Tissue or when the tooth enamel is freed from accumulated foreign materials, the materials to be removed are as small as possible

to separate the healthy bone tissue

There are numerous treatment agents and procedures for this purpose

known The most common are the various mechanical means

and hand tools, mainly from a compressed air turbine or one

Electric motor driven The basic problem of mechani¬

means then that with their help the healthy and the pathological

Tissues cannot be separated from one another with sufficient accuracy

can and the loss of healthy tissue is relatively high

One has to carry out rotary motion mechanical tools

the tissue-damaging effect of the frictional heat for a sufficient Provide cooling, which in turn requires a complicated technical solution

and is associated with great effort

Soπar and ultrasound methods are also known for dental treatment, in which the treatment is carried out using appropriate

The corresponding sound frequencies are used, the water being used as the coil liquid and as a medium transmitting the shock waves. The disadvantage of this method is that it is relatively slow and expensive

In dental practice, laser beam treatment is also

lung known, which is primarily suitable for cutting the soft tissue, but for separating the healthy and pathological tissue much

less because when they are used the carbonization of the carbon-containing or¬

ganic materials causes discoloration, while the quality of the treated area deteriorates with the increase in the energy of the laser beam, it also having to be taken into account that the Ko¬

Most such, also suitable for cutting the enamel

direction are disproportionately large

The object of the invention is to create a dental ver¬

driving and a device by means of which the separation of the pathological

and healthy tissue of the teeth with maximum protection of the healthy

the tissues, with great certainty and accuracy

can, whereby all healthy tissue of the tooth namhch both the Zahn¬

enamel as well as dentin and cement easily and without harmful ne- Effects can be cut while the dentist essentially

Chen with a treatment used when using the dental drill

technology can work

The invention is based on the knowledge that a

Appropriate energy available concentrated free liquid jet to the active

Seedy and easily controllable destruction and formation of solid materials

is excellently suited, the machined area being an immediate one

Cooling received

Based on the above knowledge, the task was solved by a

Process solved, in which at the end of a dental treatment workshop

attached nozzle a liquid of high pressure in the form of a con

centered, free liquid jet with high kinetic energy towards the

treating tooth surface is directed and the dental treatment at again

quick start-up and shutdown of the liquid flow or

automatic regulation of the liquid pressure is carried out

According to the invention, the treatment fluid is advantageously

distilled water used

It is also advantageous in accordance with the invention if the pressure of the

the liquid emerging from the nozzle is regulated between 60 and 150 MPa

Suitable for implementing the method according to the invention

nete dental treatment device, one with one for carrying out one.

Hand tool provided with a suitable treatment device

which, by the joint actuation of a lifting Send Schaltorgaπs and a foot switch can be brought into a functional connection with an energy source, it is marked according to the invention

Ending that the processing element of the hand tool by a suitable nozzle for the output of a concentrated liquid jet high pressure

is formed by a controlled by an adjustable pressure regulator

hydraulic supply unit is fed with liquid as an energy source, the hydraulic supply unit containing a hydraulic pump actuated by a drive unit and connected to a liquid container and into the feed line of this hydraulic supply line leading to the nozzle.

see pump a pneumatically controlled three way valve is built in

the pneumatic control circuit of a tool sensor valve actuated by a switching element which detects the lifting of the hand tool and a

by foot switch operated Fußveπtil are connected in series

According to the invention, it is advantageous if the drive unit of the hydraulic

draulic pump consists of a pneumatic motor that has a

pneumatic line with also the pneumatic control elements of the

hydraulic system of the device with compressed air supplying pneumati¬

the supply unit is connected

According to a further advantageous embodiment of the invention, the

the hydraulic supply unit controlling adjustable pressure regulators as

a arranged on the control panel for the stepless adjustment of the control

pressure between zero and a maximum value of suitable pneumatic Pressure regulator trained, which via a pneumatic line with a combi

Niert hydraulic control unit is connected, the one from a pneu¬

contains a mechanical piston and a hydraulic piston existing differential piston and associated stroke position detection valves

It is characteristic of an advantageous variant of this embodiment

Ending that with the one stroke position detection the hydraulic control

unit is controlled by a float which detects the liquid level of the liquid container and if it is below a minimum value

reduced liquid level preventing the build-up of the control pressure

Level switch valve is connected

After all, it is in terms of safe and reliable functioning

the device according to the invention is expedient if between the hydraulic pressure line of the hydraulic supply unit and one for the flow

return flow line when the hy-

drastic operating pressure by a certain amount in the direction of the jerk

Power line temporary opening pressure relief valve

as well as a pressure relief safety valve are installed, the latter with a when the set maximum hydraulic

Operating pressure by a certain amount of bursting rupture disc

see is

The invention will be explained in greater detail on the basis of an exemplary embodiment

explained with the accompanying drawing In the drawing, Fig. 1 shows the schematic basic structure of a possible embodiment of the

device according to the invention

As can be seen from the circuit diagram in FIG. 1, the device according to the invention basically consists of one for operation and one

Control of the necessary energy-ensuring pneumatic supply unit 1, a hydraulic supply unit 2 ensuring the sufficient pressure energy of the liquid performing the dental treatment, and a liquid container 3 connected to it

from a control panel 4 actuated control and safety elements, a tooth-treating hand tool 5, and the line connecting them

gene, wherein in the hand tool 5 for converting the pressure energy into ki¬

netic energy and to produce a concentrated liquid jet

a nozzle 6 is installed as a machining element

The pneumatic supply unit 1 consists of an electric

gate 7 and a compressor 8, being on the suction side of the compressor 8

Air filter 9 and on its pressure side during the break in operation of the compressor

a check valve 10 preventing backflow of the compressed air

is building The compressor 8 is via the check valve 10 with one of the

it generates compressed air and at the same time the pressure fluctuations

of the system steaming pneumatic accumulator 1 1 connected The

Compressor 8 is also connected to a pressure switch 12, which

Operating state of the pneumatic supply unit 1 depending

determined by the compressor pressure p _k in such a way that it at the compressor 8 a set lower limit value P _min starts at one

set the upper limit p _kmax

After the compressor 8, the pneumatic pressure line bifurcates

can be relieved via a pressure relief valve 13 in a beta

branch and a control branch

The pneumatic line 14 forming the actuating branch delivers

Via a bistable three-way valve 15 compressed air to that from the pneumatic

Motor 16 and the hydraulic pump 17 existing, work periodically

the hydraulic supply unit 2, the feed pressure using a

Pressure control valve 18 set and read on a pressure gauge 19

The value of the pneumatic feed pressure set is so

chosen that the maximum value of the er¬ by the hydraulic pump 17

generated hydraulic pressure with that in the hydraulic system

permissible pressure

On the pneumatic line 20 representing the control branch there is a

the control circuit carrying out the control of the hydraulic system is indicated

closed, the pressure with the help of a pressure control valve 21 on the Maxi¬

mumwert (pv _ma x) of the pressure required in the control circuit and set to ei¬

nem pressure gauge 22 can be read

The operating state of the hydraulic supply unit 2 and

Operating pressure of the hydraulic system is a combined hydraulic

Control unit 23 determines this combined hydraulic control unit

Unit 23 consists of a differential piston forming a common piston rod 24 attached pneumatic piston 25 and

a hydraulic piston 26 and one with the common piston

rod 24 together movable actuator 27 on the surface A-,

of the pneumatic piston 25 acts at all times through the on the control

pult 4 arranged pressure control valve 28 set control pressure p _v , the

Value between zero and the maxi¬ set on the pressure control valve 21

paint control pressure p _max can be changed (0 <p, <p _vma x) Under the Wir¬

kung on the hydraulic piston 26 (its area A ₂ substantially small

ner is transmitted as Ai) via the piston rod 24 force (F = A-ι xp _v )

stands in the hydraulic system at any time to the control pressure p _v proportio¬

naler hydraulic pressure (p _h = AJA ₂ xp _v ) That with the piston rod 24 zu¬

together movable actuator 27 stands with two stroke position detection

valves 29, 30 in functional connection with the two opposite

Sides of the bistable three-way valve 1 5 are connected by the two

Stroke detection valves 29, 30 is the upper stroke position detection valve

30 in connection with the pneumatic line 20, while the lower one

Stroke position detection valve 29 with a by the liquid level of

Liquid container 3 detecting float 31 operated level switch

valve 32 is connected in series

In front of the hydraulic pump 17 of the hydraulic supply unit

2, in which the hydraulic pump 17 must connect a liquid container 3

de hydraulic suction line 33, a liquid filter 34 is installed while

after the hydraulic pump 17, in the hy- leading to the hand tool 5 draulic pressure line 35, a check valve 36 is arranged, which during the break in operation of the hydraulic supply unit 2 or during the

Suction stroke of the hydraulic pump 17 due to the backflow of

Liquid pressure drop prevented

On the path leading to the hand tool 5, the flow of the

Liquid through a closed, pneumatically controlled hydraulic Dre¬ installed in the hydraulic pressure line in its basic position

Directional control valve 37 regulates the tool sensor valve 39 and a sensor that detects the lifting of the hand tool by a tool holding arm 38

a foot valve 40 is connected in series with the pneumatic line 20 forming the control branch

To prevent the nozzle 6 from becoming blocked, a microfilter 41 and a non-return valve 42 are built into the hand tools 5

after the use of the hand tool 5 has ended,

suck the contaminated liquid into the system as well as the formation of

Air injections in the following line section prevent that

Hand tool 5 is connected via a flexible line 43 to the hydraulic three-way valve 37 which regulates the supply of high-pressure liquid

the one in its basic position, the flexible line 43 of the hand tool

5 via a hydraulic return flow line 44 with the liquid container 3

connects

To increase the safety of the hydraulic system are in one of the

hydraulic pressure line 35 branched off and to the liquid container 3 leading return flow line 45 two pressure

greπzungsveππtile 46 and 47 installed, of which the

Control valve 46 is in functional connection with the pressure regulator 28 via a pneumatic line 48, while the pressure-limiting safety valve 47 expediently acts as a valve provided with a rupture disk

is formed

The respective operating pressure p _{h of} the hydraulic system can be read on a hydraulic pressure meter 49

The device according to the invention operates as follows

By commissioning the one controlled by the pressure switch 12

Compressor 8 of the pneumatic supply unit 1 is the pneumati¬

system is pressurized and pneumatic energy is supplied to the pneumatic motor 16 of the hydraulic supply unit 2 via the pneumatic line 14, this pneumatic motor 16 providing the hydraulic

Lische pump 17 actuates the hand tool 5 with a treatment flow

suitable pressure supplied

The hydraulic pump 17 was the one in the hydraulic

Suction line 33 built-in liquid filter 34 from the liquid container 3

aspirated liquid via the hydraulic pressure line 35 to the nozzle 6 of the

Forward hand tool 5, but this is due to the closed position

of the hydraulic three-way valve 37 is prevented until ic

Meet the requirements for operating the hand tool 5 To operate the hand tool 5, the hydraulic must

Three-way valve 37 are brought into the actuated position. A prerequisite for this is that the tool sensor valve 39 switches over when the hand tool 5 is lifted off the tool holding arm 38, the foot valve 40 also being switched over by stepping on a foot switch

Must, so that from the pneumatic line 20 via the foot valve 40 and

the tool sensor valve 39 can get compressed air to the hydraulic three-way valve 37 and this switches into the actuated position, so the hydraulic three-way valve 37 switches the treatment fluid of high pressure, appropriately

Distilled water is usually passed in the direction of the hand tool 5

leaves

The dentist can use the hand tool 5 in the manner that is customary in the case of the dental drills, only the drill is replaced here by a concentrated liquid jet, with the switching off and starting

the hand tool 5 during the treatment in a manner known per se,

by appropriate actuation of the foot valve 40 to protect the

Both the user and the patient reduce the risk of unintentional actuation by switching the hydraulic

Three-way valve 37 in an actuated position and thus the beginning of the fluid

current flow has a combined requirement in that the tool

Icrvcr.i ;! 39 by lifting the hand tool 5 from the tool holder arm 3δ

to switch and at the same time to operate the foot valve 40 As has already been mentioned, the operating state of the hydrau¬

lische Versorguπgseinheit 2 and the hydraulic pressure meter 49 ab¬

Readable operating pressure determined by the combined hydraulic control unit 23. The hydraulic operating pressure required for the respective treatment, which is expediently 60 to 70 MPa when separating soft parts, and 120 to 150 MPa when the tooth enamel is abraded is achieved by using the Control panel 4 arranged pressure regulator 28, a control pressure p _{v is} set, which - via the pneumati¬

cal line 48 to the surface _A. of the pneumatic piston 25 of the hydraulic

Control unit 23 acting - via the piston rod 24 and the much smaller

Nere surface A _{2 of} the hydraulic piston 26 causes a hydraulic operating pressure p _h proportional to the control pressure p _v . During the regulation, the actuating member 27, which is movable together with the piston rod 24, acts, as already mentioned, with two stroke position detection valves 29, 30.

together with the due to the leakage of the treatment liquid from the

hydraulic system occurring volume reduction becomes the lower

Stroke position detection valve 29 by approaching its lower stroke position

Actuating member 27 actuated before reaching its end position, that is

switched, whereby the bistable three-way valve 15 in such a switching

Positioned where there is the compressed air to the pneumatic motor 16

passes, so the hydraulic supply unit starts to work

After the fluid supply provided by the hydraulic pump 17

quantity is greater than the possible maximum value of consumption, the Difference of the two amounts stored by the combined hydraulic control unit 23 so that the differential piston and thus together the actuating member 27 move in the direction of the upper end position, whereby the

Volume of the hydraulic system is increased before reaching the above

Ren end position, the upper stroke position detection valve 30 is actuated by the actuating member 27, whereby the bistable three-way valve 15 is brought into such a switching position, where it closes the pneumatic line 14

and vented the line section leading to the pneumatic motor 16

In this way, the combined hydraulic control unit 23 also fulfills the

Function of a hydraulic accumulator, since due to its flexibility it allows a change in volume of the hydraulic system and the hydraulic

operating pressure regardless of the current operating state of the

hydraulic supply unit 2 at a constant value

As already mentioned, the lower stroke position detection valve is

29 of the hydraulic control unit 23 with a level switching valve 32 in series

switched, which is assigned to the liquid container 3 If the liquid level in the liquid container 3 is below a set lower limit

value decreases, then the leading to the lower stroke position detection valve 29

Line section through the level switching operated with the float 31

valve 32 separated and vented so that the bistable three-way valve 15 infol¬

ge dcε switching the lower stroke position detection valve 29 into one

Switch position is brought in which the commissioning of the hydraulic

Supply unit 2 is prevented The pressure limiting

tion valves 46 and 47 The operating pressure relief valve 46 leaves the incorrect operation of the combined hydraulic control unit 23, at ei¬

slightly higher than the intended hydraulic operating pressure p _h

Pressure value (p _h + Δ _h ), liquid temporarily escapes from the high-pressure chamber via the return flow line 45 into the liquid container 3 and thereby prevents a further increase in the pressure

The pressure relief valve 47 only occurs in the event of a

possible faulty function of the operating pressure relief valve 46

at a slightly higher maximum hydraulic operating pressure p _hm a

Value (p ma _x + Δ _p ), in operation, in that the rupture disc built into the valve tears open. This creates a "short circuit" between the high-pressure chamber and the return flow line 45, and the device can be reached up to the end

the error can no longer be used

The solution according to the invention explained above can be used in numerous dentists

treatments are used excellently, including at the

selective, tissue-friendly removal of rotten tooth enamel, dentin

and cement, during the removal of the ver¬ adhering to the tooth surface

limed plaque, with the isolated removal of the soft tissue of the tooth pulp

pen cavity and in the expansion or preparation of the tooth sausage

cell channels The method according to the invention and the device according to the invention

tion have numerous advantages over conventional dental treatment methods and devices

1) With the distilled water adjustable pressure and jet

knife, which is a biologically absolutely inert material and therefore represents an ideal liquid for treatment purposes, all healthy tissues of the tooth, ie the enamel, dentin and Ze¬

be cut and shaped (prepared) equally

2) By regulating the water pressure, the strength of the water

can be adapted to the hardness of the tooth tissue to be treated, as a result of which the pathological (rotten) and the healthy tissue with a large amount of tissue

can be separated from each other after by the water

only the pathological tissue is removed so that the treatment can be carried out without loss of healthy tissue 3) At the border of the pathological and healthy tissue, the disease can

uniformity of the edges of the diseased area by increasing the

Pressure can be smoothed in a simple manner

4) Through the design of the treatment water jet output

the hand tool can be used with the conventional dental drill

Treatment techniques are largely retained

5) In addition to their accuracy, their gentle and safe F n t.ons-

wise and easy to use, the device according to the invention

are manufactured relatively cheaply

Claims

PATENT CLAIMS

1 Dental procedure for separating various, wah¬

rend the dental treatment on the border of the healthy bone tissue to be removed materials or, if necessary, for abrasion of the healthy bone tissue, characterized in that on a

A liquid nozzle attached to the end of a dental hand tool

high pressure in the form of a concentrated, free liquid jet with high kinetic energy is directed onto the tooth surface to be treated

and dental treatment with repeated start-ups and shutdowns

Liquid flow or with pneumatic control of the liquid pressure is carried out

2 The method according to claim 1, characterized in that as Be¬

distilled water is used

3 The method according to claim 1 or 2, characterized in that

the hydraulic operating pressure is regulated between 60 and 150 MPa

4 Dental device for separating various, wah¬

dental treatment on the border of healthy bones

fabrics to be removed or, if necessary, to abrade the

healthy bone tissue, with a hand tool, which one to carry out

tion of a dental treatment suitable processing organ, wherein

the hand tool by lifting it together detecting Schaltorgaπs and a foot switch with an energy source in

Functional connection can be brought, characterized in that

the processing element of the hand tool (5) by an ei¬ for output

Nozzle suitable for concentrated liquid jet of high pressure (6)

is formed, which is controlled by an adjustable pressure regulator (28)

erten hydraulic supply unit (2) as an energy source with liquid

is fed, the hydraulic supply unit (2) one by one

Drive unit actuated and connected to a liquid container (3)

hydraulic pump (17) contains and into the feeder leading to the nozzle (6)

device of this hydraulic pump (17) a pneumatically controlled three-way

valve (37) is installed, in the pneumatic control circuit one by one

the switching device which actuates the lifting of the hand tool (5)

Tool sensor valve (39) and a foot operated by a foot switch

valve (40) are connected in series

5 Apparatus according to claim 4, characterized in that the

Drive unit of the hydraulic pump (17) from a pneumatic Mo¬

gate (16), which also has a pneumatic line (14)

pneumatic controls of the hydraulic system of the device with

Compressed air supplying pneumatic supply unit (1) is connected

6 Device according to claim 4 or 5, characterized in that

the adjustable pressure regulator controlling the hydraulic supply unit (2)

ler than one on the control panel (4), for stepless adjustment of the control pressure (p _v ) between zero and a maximum value (p _vma χ)

Neter pneumatic pressure regulator (28) is formed, which ver¬ via a pneumatic line (48) with a combined hydraulic control unit (23)

is bound, which contains a differential piston consisting of a pneumatic piston (25) and a hydraulic piston (26) as well as stroke position detection valves (29, 30) associated therewith

7 Device according to claim 6, characterized in that with

the one stroke position detection valve (29) of the hydraulic control unit (23)

one by detecting the liquid level of the liquid container (3)

which controls the float (31) and prevents the build-up of the control pressure (p _v ) when the liquid level has dropped below a minimum value

Level switch valve (32) is connected

8 Device according to one of claims 4 to 7 thereby gekenn¬

records that between the hydraulic pressure line (35) of the hydraulic

Supply unit (2) and a jerk leading to the liquid container (3)

Power line (45) on when the hydraulic operating pressure is exceeded

(p _h ) by a certain amount in the direction of the return flow line (45)

operating pressure relief valve (46) and a pressure

border security valve (47) are installed, the latter with a

when exceeding the set maximum hydraulic pressure

kes (P m _ax ) by a certain amount of rupture disc