JP2717252B2 - Sterilization method and sterilization device for object to be sterilized - Google Patents

Description

The present invention relates to a dentist for removing bacteria adhered to the surface of a handpiece and an inner surface of an air hole used for treating a patient, and bacteria adhered to an object to be sterilized. The present invention relates to a method and an apparatus for sterilizing with ozone gas.

2. Description of the Related Art Conventionally, a sterilizer for this kind of object is generally performed by high-temperature heating using high-pressure steam using an autoclave, but a dentist's handpiece is a chuck for attaching and detaching a small drill, which is rotated at a high speed. It is composed of precise mechanical parts such as an air turbine for cooling, or a device for cooling the tip of a drill, and therefore, there is a possibility that the distortion generated during high-temperature heating may impair the accuracy. Therefore, sufficient disinfection and sterilization cannot be performed, which may cause a serious problem in hygiene.

Approximately 1 to increase to the temperature required for sterilization (about 130 ° C)
5 minutes, about 20 minutes to completely extinguish at that temperature, about 10 minutes to cool down, a total of at least about 45 minutes, it was not possible to rapidly sterilize the handpiece, which was extremely inconvenient .

Apart from the above, some types of sterilizers for this type of equipment use ethylene oxide gas, but in this case, in addition to the sterilization time of at least 50 minutes, repeated pressurization and depressurization of the gas is required. There is a drawback that harmful and carcinogenic ethylene oxide gas remains on the handpiece.

To avoid these problems, it is conceivable to sterilize using high-concentration ozone gas that has strong sterilizing power and no residual toxicity, but the handpiece immediately after treating the patient gets wet around the In many cases, even if the handpiece in that state is put in ozone gas in a sterilization chamber, the ozone gas does not sufficiently reach the bacteria in the water film, and it is difficult to completely sterilize the ozone gas.

In addition, bacteria that adhere to the surface of the handpiece are placed at room temperature or lower, or some bacteria are difficult to sterilize when they are in a dry state, especially spores such as Bacillus subtilis. Maintains a dense shell composition, so ozone gas is blocked by the shell and cannot pass through it to reach the protoplasm inside it, which makes it extremely difficult to sterilize bacteria. Furthermore, the surface of the handpiece is easily exposed to ozone gas, so that it is relatively easy to sterilize it. However, since the inner surface of the air hole of the handpiece is hardly exposed to ozone gas, it is practically extremely difficult to sterilize it. Have difficulty.

The object of the present invention is to solve each of the above-mentioned problems when performing high-temperature heating by an autoclave and sterilizing with ethylene oxide gas and ozone gas, and particularly to a handpiece. Bacterial spores that adhere to the soil are also most effectively sterilized.

Another object of the present invention is to prevent the above-mentioned difficulty in sterilizing a wet handpiece immediately after treatment with ozone gas and the adverse effect on the human body when high-concentration ozone gas is used.

Another object is to provide a device that facilitates sterilization of the surface of the handpiece and the inner surface of the air vent.

Another object is to improve the gas generation efficiency of the ozonizer and to reduce its size.

Means for Solving the Problems According to the present invention, an object to be sterilized such as a handpiece is preliminarily wetted and accommodated in a sterilization chamber communicating with an oxygen source such as an oxygen cylinder and sealed, and supplied from the oxygen source. At least 10,000 ppm or more when introduced into the oxygen ozonizer, preferably 15
After producing ozonized oxygen gas having an ozone concentration of 000 ppm or more, heating this, and then passing through the sterilization chamber to completely replace the air in the sterilization chamber with ozonized oxygen gas,
The water attached to the object to be sterilized such as the hand piece is partially evaporated, and then the communication between the sterilization chamber and the oxygen source is cut off, and the ozonized oxygen gas is heated at the sterilization chamber entrance. Bacteria that adhere to an object to be sterilized, such as a handpiece, with the ozonized oxygen gas while increasing the concentration of ozone to at least 20,000 ppm, preferably not less than 30,000 ppm without wasting oxygen by circulating between the ozonizer and the ozonizer. Is sterilized in a swollen state.

In order to achieve this, in a sterilization chamber for sterilizing an object to be sterilized in a wet state, an oxygen source is supplied to one side of the sterilization chamber via a heater and an ozonizer, and residual ozone is decomposed to the other side of the sterilization chamber. By connecting the exhaust valves to the atmosphere through the ozone killer, the ozone concentration of 10
000 ppm or more, while supplying ozonized oxygen gas at a temperature of 30 ° C. to 70 ° C., the inside of the sterilization chamber is replaced with ozonized oxygen gas, and the ozonized oxygen gas is further supplied to the sterilization chamber via a heater, an ozonizer, and a circulation pump. The sterilization target is sterilized by increasing the ozone concentration inside the sterilization chamber, and then the sterilization chamber, the ozone killer, the ozone monitor, and the circulation pump are connected so that the ozone gas can be circulated. This is a sterilization apparatus for sterilizing an object such as a dental handpiece for reducing the concentration of ozonized oxygen gas.

Further, in the above-mentioned sterilization apparatus, a receiving seat for airtightly inserting the handpiece base is provided in the sterilization chamber, a communication hole communicating with the through-hole of the handpiece is provided in the receiving seat, and the communication hole is switched to the discharge valve. Connected, the one outlet of the switching discharge valve is communicated with the outside air through an ozone killer, and the other outlet of the switching discharge valve is communicated with the inlet side of an ozonizer through a circulation pump, thereby allowing the inside of the sterilization chamber to enter. The introduced ozonized oxygen gas can be released to the outside air through the inner surface of the through hole of the handpiece, or can be supplied and circulated to the ozonizer inlet.

Action Wipe a dental handpiece in a sterile room with a wet absorbent cotton or paper napkin, put the surface in a wet state in advance, close the door, and supply oxygen supplied from an oxygen source through an ozonizer at least 10,000 ppm, preferably 15000ppm
Ozonized oxygen gas having an ozone concentration of 30 ° C. to 70 ° C., preferably heated to a temperature of about 50 ° C., is supplied to a sterilization chamber, and is supplied through an ozone killer. To the outside to completely replace the air in the sterilization chamber. During this time, part of the water film adhering to the surface of the handpiece and the inner surface of the air hole evaporates, and ozone is adsorbed on the surface to form an ozone water surface layer, and the temperature of the water film rises. Then, the swelling of the shell of the bacterial cell membrane in the water film due to heating starts. Next, the ozonized oxygen gas is circulated between the ozonizer and the sterilization chamber while being heated at the sterilization chamber entrance, and the ozone concentration of the ozonized oxygen gas in the sterilization chamber is increased to at least 20,000 ppm, preferably to 30,000 ppm or more. The high-concentration ozone gas forms a higher-concentration ozone water surface layer, which scans all the bacteria exposed on the surface of the handpiece and the inner surface of the air hole as the water film dries. The shell, which has been swollen by contact, penetrates into the upper part of the penetration and is surely sterilized.
After that is completed, the ozonizer is stopped, the sterilization chamber is communicated with the ozone killer, and the sterilized ozonized oxygen gas in the sterilization chamber is discharged between the ozone killer, the ozone sensor, and the sterilization chamber by appropriate means such as driving a circulation pump. During this time, ozone gas is removed by heating the ozone gas with an ozone killer or decomposing by a catalyst or adsorbing by an adsorbent, and the amount of residual ozone is detected by an ozone sensor. The replacement of high-concentration ozone gas by a cleaning action to gradually reduce its concentration. After confirming with an ozone monitor that the concentration has dropped and there is no danger to the human body, the door is opened, a sterilized handpiece is taken out, and used again for treating a patient.

Embodiment FIGS. 1 to 3 show a sterilization apparatus for carrying out the sterilization method of the present invention. In a sterilization chamber 1, a patient's saliva, blood, and the like are wiped with wet absorbent cotton, paper napkin, paper towel, or the like. After the handpiece 21 is wet with the attached water film
The base 21c of the cover 2 is airtightly fitted into the seat 25 and accommodated therein.
Seal. The receiving seat 25 has a communication hole 25a and the suction pipe 2
The suction pipe 27 is connected to the inlet 7b of the ozonizer 7 via the valve 17 and the circulation pump 16 and to the inlet 11a of the ozone killer 11 via the valve 34. The suction pipe 2
7 is further connected to the outlet 11b of the ozone killer 11 via a valve 41, a circulation pump 38, an ozone monitor 37, and a valve 33.

The sterilization chamber has another gas inlet 13 and a valve 39.
Is connected to the outlet 38a of the circulation pump 38, and another gas outlet 14 is connected to the inlet 16a of the circulation pump 16 via the valve 15.

 40 is a fan for cooling the ozonizer.

First, the valves 4 and 5 are opened, and the oxygen source 6 such as an oxygen cylinder is opened.
Is passed through an ozonizer 7 to generate an ozonized oxygen gas having an ozone concentration of at least 10,000 ppm, and then heated to 30 ° C. to 70 ° C. by a heater 8;
It is passed through a gas inlet 3 provided on one side of the sterilization chamber 1 through the sterilization chamber 1.
Oxygen gas from which ozone has been removed through a gas discharge port 9 provided on the other side of the sterilization chamber 1 through an exhaust valve 10, an ozone killer 11, and a valve 12 which pass through the sterilization chamber 1 A1
Discharge into the atmosphere in two directions. At this time, valves 15, 17, 33, 3
4, 39 and 41 are closed.

This replaces the air in the sterilization chamber with ozonized oxygen gas.

At this time, the water film 23 adhering to the surface of the handpiece 21 is generated by the heated ozonized oxygen gas passing into the sterilization chamber 1.
Is evaporated to reduce the thickness of the water film layer from Δd + d by Δd as shown in FIG.

In this process, the surface layer 23a of the water film 23 absorbs ozone and forms a thin ozone water layer having a strong sterilizing power here,
The inner water layer 23b does not enter ozone and does not form ozone water, so that there is no sterilization effect by ozone. Therefore, at this stage, the bacteria 24 in most of the water layer 23b except the surface layer 23a are not sterilized by ozone.

However, the temperature of the water film 23 rises due to the contact with the heated ozonized oxygen gas. As a result, the bacterial cell membrane is heated under wet conditions and the shell swells, and the ozone in the ozone water passes therethrough. It becomes easy to enter inside.

Next, when the valve 34 is opened and the valve 10 is closed, the heated ozonized oxygen gas introduced into the sterilization chamber 1 enters from the head 21a of the handpiece 21 into the air hole 21b therein, and Through the communication hole 25a, the suction pipe 27, the valve 34, and the ozone killer 11, the ozone is released to the outside air in a state where ozone is removed, and during this time, the same as described above for the attached water film on the inner surface of the through hole and the bacteria in the water film. Evaporation of the water film, formation of ozone water surface,
Swelling of the shell of the bacterial cell membrane takes place.

Thereafter, the replacement of the air in the sterilization chamber with the ozonized oxygen gas is completed while repeating the operation of opening the valve 10 and closing the valve 34, opening the valve 34 and closing the valve 10.

Next, close the valves 5, 17, 10, and 34, open the valve 15, and set the sterilization chamber 1
Ozonized oxygen gas in the valve 15, circulation pump 16, ozonizer
7. The gas is supplied from the gas inlet 3 of the sterilization chamber 1 into the sterilization chamber 1 via the valve 4 and the heater 8, and circulates.

Next, the valve 17 is opened and the valve 15 is closed, and the ozonized oxygen gas passes through the internal through hole 21b of the handpiece 21, passes through the upper valve 17, the circulation pump 16, the ozonizer 7, the valve 4, and the heater 8 to perform the sterilization. The gas circulates from the gas inlet 3 of the chamber 1 into the chamber, and thereafter, the valves 15 and 17
The operation of alternately opening and closing is repeated. In this manner, the ozonized oxygen gas for sterilization is circulated between the sterilization chamber 1 and the through hole 21b and the ozonizer 10, and the ozone concentration of the ozonized oxygen gas in the sterilization chamber 1 is set to at least 20000 ppm, preferably By increasing the concentration to 30000 ppm or more, this high-concentration ozone gas is brought into contact with the outer surface of the handpiece 21 and the surface of the moisture film adhered to the inner surface of the through-hole, thereby greatly increasing the ozone concentration of the ozone water layer on the surface. , Greatly increase its sterilizing power. Then, as the water film evaporates, the bacteria 24 in the water film are gradually exposed, but at this time, the ozone water layer always comes into direct contact with the exposed bacteria 24. At this time, the bacteria are further swollen due to the temperature of the ozone gas under moist conditions, and in this state, high-concentration ozone penetrates the cell membrane very efficiently through the cell membrane to completely sterilize the bacteria.

The state of sterilization in the sterilization chamber 1 at this time is
5, 6 and 7, of which FIG. 5 shows dry bacteria 24.
2 is an enlarged cross-sectional view of the spores of Bacillus subtilis as an example. The cell membrane that forms the outer part of the protoplasm 27 has a shell 26 structure and an extremely dense tissue structure.
Cannot reach 28 and cannot be sterilized.

FIG. 6 shows a state in which the shell 26 is swollen by applying a heated ozone gas in a wet state. At this time, the ozone molecules 20 outside the shell 26 can rapidly enter the shell 26, The reaction rate for oxidizing this is also extremely high, forming a through hole 26a in the shell 26 in a short time, passing through it and reaching the protoplast 28,
It can be completely sterilized immediately.

FIG. 7 shows the state of the sterilized bacterium 24. It is confirmed by an electron microscope that a part 28a of the protoplasm 28 has been pushed out to the surface of the shell 26 through the through hole 26a.

After the outer surface of the hand piece 21 and the inner surface of the through hole are sterilized in this manner, the operations of the ozonizer 7, the circulation pump 16, and the heater 8 are stopped, and the valves 4, 12, 15, 17, 17, and 34 are closed. , Valve 10,33,3
Opening 9, 41 and operating the circulation pump 38, the sterilization chamber 1
The high-concentration ozonized oxygen gas in the through hole 21b of the handpiece 21 is discharged from the outlet 9, the valve 10, the ozone killer 11, the valve 33, the ozone monitor 37, the circulation pump 38, the valve 39, the gas inlet 13 and the valve 41, Circulation to the sterilization chamber 1 is performed through the pipe 27 and the through hole 21b, during which the ozone concentration is rapidly reduced by the action of the ozone killer 11.

When the ozone concentration is reduced to such an extent that it does not harm the human body, the ozone monitor 37 confirms the decrease, opens the lid 2 of the sterilization chamber 1 and takes out the handpiece 21 therein for use.

As shown in FIGS. 2 and 3, the above-mentioned ozonizer 7 has a planar induction electrode 46 embedded in a cylindrical dielectric 45 made of fine ceramic, and A linear corona discharge electrode 47 is provided, and a high-frequency high-voltage power supply 48 is connected between the electrodes 46 and 47.
A high frequency high voltage is applied to the surface of the cylindrical dielectric 45 on the side of the linear corona discharge electrode 47 to generate a creeping discharge 49, and the oxygen gas supplied from the inlet 7b is converted into ozone gas.

At this time, the ozone generation efficiency can be improved by cooling the ozonizer 7 with the cooling fan 40 as shown in FIG.

The sterilization apparatus shown in FIG. 8 shows another embodiment of the present invention, in which the communication between the sterilization chamber 1 and the pressure chamber 44 of the pressure vibrating device 43 is established by a communication space 29. The pressure vibration device 43 is a cylinder
A piston 31 is slidably fitted in 30 and the piston 31
31 and the crankshaft 42 are connected via the connecting rod 32 and the crank arm 35, and the crankshaft 42 is rotated by an electric motor or the like,
A change in pressure in the pressure chamber 44 caused by reciprocating the piston 31 in the cylinder 30 is transmitted to the sterilization chamber 1 through the communication pipe 29 as an exciting force.

At this time, when all the valves 4, 10, 39, and 15 connected to the sterilization chamber 1 are closed in a state where the sterilization chamber 1 is filled with the ozonized oxygen gas, the ozonized oxygen gas in the sterilization chamber 1 is closed. The pressure of the gas oscillates due to the exciting force. Therefore, the object to be sterilized 18 on the wire mesh 19 which is previously sealed in the sterilization chamber 1 is repeatedly subjected to pressurization and depressurization, and the ozonized oxygen gas flows deeply into the inside of the depressurized object and into gaps. Bacteria present in the bacteria can be completely sterilized.

More specifically, the vibrating device 14 is not limited to the above-described one including the cylinder 30 and the piston 31. Instead, an ordinary diaphragm and its contraction / expansion means, such as a crank in FIG. Combine shaft 42, crank arm 35, connecting rod 32 and electric motor
A guide rail for the piston 30 and the piston 31 may be used.

At this time, the opening of the diaphragm is attached to the communication pipe 29, and the other end is attached to the sliding portion corresponding to the piston 31.

In the drawing symbols of the embodiment of FIG. 8, the same symbols as those used in FIG. 1 have the same names and the same functions and effects as those of FIG. It will be apparent from the description of FIG.

Effects The present invention is as described above, and since an oxygen source and an ozonizer are connected to a sterilization chamber via a heater, it is possible to supply a dry warmed ozonized oxygen gas to the sterilization chamber.
When the wet handpiece is placed in the sterilization chamber, a strong sterilizing force is applied from the beginning to the surface of the handpiece and the surface of the adhered moisture layer on the inner surface of the through-hole in the process of first replacing the air in the sterilization chamber with ozonized oxygen gas. A sterilizable state is formed by forming an ozone aqueous layer having the following properties, and the cell membrane or outer shell on the surface of the bacterium can be brought into a swollen state that can be easily sterilized.

At this time, since the ozonized oxygen gas generated by the ozonizer in the following process is circulated in the sterilization chamber and in the handpiece through hole and between the ozonizer while heating, the ozone concentration in the ozone water surface layer is further increased, and Evaporates the water film,
The swelling of the outer shell of the bacteria is further promoted, and in the process of exposing the bacteria accompanying the water film evaporation, the above-mentioned ozone water surface layer having a strong sterilizing power can be applied to all the bacteria to completely sterilize it. In other words, high-concentration ozone molecules in the surface layer of ozone water easily penetrate into the bacterial swelling swollen under a wet condition, form a through-hole in this by an oxygen reaction, and ozone easily enters the bacteria into the protoplasm, It can be sterilized in a short time.

Further, according to the present invention, the sterilization chamber and the handpiece through-hole and the ozone killer are connected with piping so that the ozonized oxygen gas having a high concentration of residual ozone can be circulated after the sterilization operation is completed between them. Each time the circulation is repeated, the ozone killer breaks down ozone harmful to the human body into oxygen, then opens the lid of the sterilization chamber and removes the handpiece inside the chamber, but the ozone gas is discharged from the sterilization chamber to the outside air. Because there is nothing, there is no danger to the human body and it is safe. Also, by connecting the ozone monitor to the ozone killer, after confirming that the ozone gas concentration has been sufficiently reduced by the ozone monitor, the lid can be opened and the sterilized instrument can be taken out. There is no danger of injury to the human body due to flowing inside.

[Brief description of the drawings]

FIG. 1 is a gas circuit diagram of a sterilizer for carrying out the sterilization method of the present invention, FIG. 2 is an enlarged vertical sectional view of a part of FIG. 1, and FIG. 3 is a line III-III in FIG. , FIG. 4 is an enlarged sectional view of a part of FIG. 1, FIGS. 5, 6, and 7 are enlarged sectional views of bacteria, respectively, and FIG. 8 is a gas circuit diagram of another embodiment of the sterilizer. . 1 ... Sterilization chamber 4,5 ... Valve 6 ... Oxygen source 7 ... Ozonizer 8 ... Heating device 10 ... Valve 11 ... Ozone killer 12,15 ... Valve 16 ... Circulation pump 17 ... Valve 21 ... … Handpiece 25… Receptacle 27 …… Suction pipe 33,34 …… Valve 37… Ozone monitor 38 …… Circulation pump 39,41 …… Valve 43 …… Pressurizing device 44 …… Pressure chamber

Claims (3)

(57) [Claims] In a sterilization chamber for sterilizing an object to be sterilized in a wet state, one side of the sterilization chamber is supplied with an oxygen source through a heater and an ozonizer, and the other side of the sterilization chamber is supplied with outside air through an ozone killer. By communicating the discharge valves that communicate with each other, the inside of the sterilization chamber is replaced with ozonized oxygen gas while supplying ozone oxygen gas having an ozone concentration of 10,000 ppm or more and a temperature of 30 ° C. to 70 ° C. to the sterilization chamber, and further sterilization. The ozonizer is connected to the chamber through a heater and a circulation pump so that the ozonized oxygen gas can be circulated, and the ozone killer, the ozone monitor and the circulation pump can be circulated to the sterilization chamber. Device for sterilizing an object to be sterilized, characterized by communication 2. A sterilization apparatus for an object to be sterilized according to claim 1, wherein a pressure chamber of a pressure vibrator is connected to the sterilization chamber. 3. A sterilization apparatus according to claim 1, further comprising: a receiving seat into which the base of the handpiece can be airtightly inserted into the sterilization chamber; and a communication hole communicating with the through-hole of the handpiece. Switching the communication hole, one outlet of the discharge valve,
The other outlet of the switching discharge valve is connected to the inlet side of the ozonizer via a circulation pump through an ozone killer, thereby allowing the ozonized gas introduced into the sterilization chamber to pass through the through hole of the handpiece. Dental handpiece sterilizer characterized by being able to discharge to the outside air via the inner surface or supply and circulate to the ozonizer inlet