JP2023067702A - Reamer used for dental handpiece, manufacturing method of reamer and dental handpiece including reamer - Google Patents

Abstract

To address inadequacy of traditional files when performing treatment of actively digging or penetrating a tooth root, and to provide a dedicated treatment tool for actively digging or penetrating the tooth root, and a manufacturing method thereof.SOLUTION: A reamer 100 comprises an insertion part 101 for inserting into a dental handpiece, and a needle part 102 insert-molded thereto. A stainless alloy with a full length of 25 mm, a tip diameter of 0.25 mm and a taper angle of 2/100 is used as the needle part 102 (S1), and a tip end 103 of the needle part 102 with a circular cross section is press-worked into a flat shape, so that protrusions 104 are formed on both ends of the flat part (S2). In other words, two protrusions 104 in total are provided.SELECTED DRAWING: Figure 1

Description

TECHNICAL FIELD The present invention relates to a reamer attached to a dental handpiece and used for treatment such as root penetration.

A root canal, such as when the dentist scrapes the wall of the patient's decayed tooth root, removes a pus clot at the tip of the root, removes filling material left over from previous treatments, or removes nerves. It is common to use a file or a reamer for such treatments. Reamers are named from reaming (unfolding) and files are from filing. These items are color-coded according to their purpose and size, and have symbols and numbers printed on them. In addition, they consist of a needle part that is inserted into the root canal and a grip part behind it, and the needle part is generally made by twisting an elongated metal plate made of a metal material such as stainless steel or nickel titanium. be.

The article on the following Internet site is easy to understand about the treatment method for the nerve of the tooth as described above.

Internet WWW site <URL: http://mushiba-labo. com/? p=10133>

A reamer is for reaming (widening) the root canal of a tooth, and a file is for filing the root canal of a tooth. However, it was found that the above method is insufficient when trying to perform not only treatment to widen or smooth the wall of the root canal, but also treatment to actively dig and penetrate the root canal. .

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the above-described problems and to provide a dedicated therapeutic instrument capable of actively excavating or penetrating the root of a tooth.

Prior to solving the above problems, the inventor of the present invention noticed the following problems. In other words, the shape of the root canal differs from patient to patient and from tooth to tooth even in the same patient. Root canals are generally not straight but curved at the tip. For this reason, the above-mentioned reamers and files act on the wall surface of the root canal. must be such that it can exert sufficient action. Otherwise, the wall surface of the bent portion of the root canal will continue to be hit by the reciprocating motion. If the treatment of digging and penetrating the root of the tooth can be performed more accurately and quickly, it will be less fatigued and comfortable for both the patient and the dentist. should also contribute to

Therefore, I decided to improve the reamer, which consists of a needle part and a grip part behind it (which can be held with the fingertips, but which is attached to a dental handpiece). The reason why it is called a reamer is that it is used to excavate or penetrate the tooth root, that is, to ream (spread) the tooth root. However, there is no problem in calling this invention a penetrating file.

The above object is achieved by providing a reamer for use in a dental handpiece, characterized in that a plurality of protrusions are formed on the distal end of the needle portion of the reamer. Conventional reamers and files generally have a needle taper angle of 2 degrees. The needle portion of the reamer of the present invention may also follow this, but it is not necessarily limited to this. The present invention is characterized in that the circumference of the needle is formed smoothly like a sewing needle, and that the tip of the needle is formed with a plurality of projections.

Since the periphery of the needle portion is formed smoothly, there is an advantage that the wall surface of the root canal is not affected when the needle portion is bent along the curved portion of the root canal. The needle smoothly reciprocates in the root canal, and there is an advantage in that treatment can be performed by digging and penetrating the tooth root with a plurality of protrusions on the tip. Conventional reamers and file needle tips do not have a structure like the multiple protrusions of the present invention.

By the way, the present inventor has noticed that the needles of the conventional files have the following problems. When a file is attached to a dental handpiece and used, the handpiece includes a housing, a detachable section for a tooth cutting file provided in the housing for reciprocating movement, and the attachment and detachment contained in the housing. A reciprocating motion generator for reciprocating the file by applying high-speed rotation of the micromotor to the reciprocating motion. As a standard for a file attached to such a dental handpiece, the diameter of the tip of the needle is 0.25 mm, which is 1/100 of the standard #25, and the diameter 16 mm behind is 0.25 mm. Since the taper is 2/100, it is 0.57 mm.

When a file having such a shape is attached to a dental handpiece and used, the tip of the needle portion of the file is bent excessively when the file is reciprocated at high speed, and the root canal is damaged. It was discovered that the force that shears the wall may weaken. If the tip portion bends too much, the efficiency of root canal enlargement will be lowered, and inconveniences such as leaving infected dentin and gutta-percha will occur. Careful observation of the excessive bending portion of #25 in the above example showed that it was about 3 mm from the tip portion.

Excessive bending of the needle portion of the conventional file leads to bouncing and vibration of the needle portion. If you think that power can be killed, we can offer the following solutions. That is, a reamer is attached to a needle portion with a taper angle of approximately 2 degrees, and a new tip portion is formed by cutting about 3 mm from the tip portion, and a plurality of projections are formed on the new tip portion. bottom. As for the taper angle of the needle portion, it is sufficient to follow the point that conventional reamers and files generally have a taper angle of the needle portion of 2 degrees, but this angle is not necessarily limited.

In order to suppress excessive bending of the tip of the file, it is also possible to make a needle portion of a short size by excluding a portion that is likely to bend excessively from the beginning while maintaining the prescribed angle of 2/100. In other words, it is sufficient to manufacture the tip portion having a diameter of 0.31 mm from the beginning. A plurality of protrusions are formed in such a tip portion.

Strangely enough, according to the configuration of the present invention, it was possible to obtain a reamer in which the needle portion as a whole had the necessary deflection for advancing through the root canal, but no portion was excessively bent. In this way, excessive bending is eliminated, the force for digging and penetrating the tooth root is reduced, and the efficiency of digging and penetrating the tooth root is improved.

According to the first aspect of the invention, four projections can be formed at four-fold symmetrical positions on the distal end of the needle. Although it is preferable that the protrusions are provided with rotational symmetry such as 2-fold, 3-fold, 4-fold, and 5-fold symmetry, even if the number of remainders is increased, the processing of the tip portion becomes difficult. Therefore, in the embodiments described later, 2-fold, 3-fold, and 4-fold symmetry are taken up.

Regarding the method of manufacturing the projection, a surface perpendicular to the axis of the needle portion is formed on the tip of the needle portion of the reamer and placed, and the corners of this circular surface are placed at four-fold symmetrical positions, for example automatically. A method of forming four projections by shaving the valleys by micromachining with a lathe and quenching is mentioned. Crown processing or multi-slit processing may be performed. A peak is formed between the valleys, and a concentric stepped portion may be formed there. In addition, in order to reduce cutting resistance, a cutter that applies ultrasonic vibration to a rotating cutting tool is used to make a slit (cut) across the circular surface. A method for forming two projections with two-fold symmetry is raised. The places where the cuts are made are the valleys, and the gaps between the cuts are the peaks, that is, the protrusions. A step of plating the cut portion may be added.

As for the method of manufacturing the projections, there is a method of forming two projections with two-fold symmetry by making a slit (cut) across the needle portion, for example, by using a laser engraving machine at the tip of the needle portion of the reamer. increase. Alternatively, the laser engraving can be performed after providing the circular surface as described above. Since fine engraving is possible with a laser engraving machine, it is possible to form even finer projections with 3-fold symmetry, which is an odd number, and 4-fold symmetry, where the cut is a cross.

Next, the periphery of the needle portion can be plated with good lubricity. It is possible to reduce the action of the side portion of the needle portion on the wall surface of the root canal in a non-linear root canal.

This plating can be carbon coating or DLC (Diamond-Like Carbon) coating. By coating with carbon, it is possible to impart better lubricity to the periphery of the surface of the needle. Diamond-like carbon is amorphous hard carbon with physical properties intermediate between those of diamond and graphite, and this coating can form nano-level thin films on metal surfaces. Although the cost is somewhat higher, it is possible to obtain a surface with a low coefficient of wear, ie, a highly lubricating metal surface, which is convenient for reciprocating movement in the root canal.

The reamer of the present invention is driven by a dental handpiece, and it is preferable that the reamer of the present invention can be detachably attached to the dental handpiece. A reamer may be attached to a dental handpiece, but cleaning the entire head of the dental handpiece is difficult in a sense. Therefore, if it is possible to replace the reamer and use it, it will be very preferable from a sanitary point of view. A dental handpiece equipped with the reamer of the present invention is also within the scope of the present invention.

In addition, the present invention is characterized in that the circumference of the needle portion is formed smoothly like a sewing needle, and that a plurality of protrusions are formed at the tip portion of the needle portion. In order to obtain the smoothness of a sewing needle in this way, even if the needle part is not made of a single metal rod, but is made of, for example, three metal rods bundled together and twisted, the needle must be smooth. If the resistance around the part is small, it can be used sufficiently. Therefore, the scope of the right of the present invention also includes a method for manufacturing a reamer used in a dental handpiece in which a plurality of protrusions are provided at the tip of the needle portion of the reamer by untying the tip portion of the needle portion of the reamer composed of twisted wires. be within. Even if the needle portion is provided by twisting a single metal plate, the periphery of the needle portion is formed smoothly, and a plurality of projections are formed on the tip of the needle portion. It is within the scope of rights of this invention.

Since the present invention is formed by forming a plurality of protrusions on the tip of the needle portion of the reamer, when this is attached to a dental handpiece and root canal treatment is performed, treatment that digs and penetrates the root can be performed. This has the effect of being more reliable and quicker.

FIG. 2 is an explanatory diagram of Example 1; FIG. 2 is an explanatory diagram of the manufacturing method of Example 1; FIG. 2 is an explanatory diagram of a usage state of Example 1; FIG. 11 is an explanatory diagram of Example 2; FIG. 11 is an explanatory view of Example 2 as viewed from the distal direction; FIG. 10 is an explanatory diagram of the manufacturing method of Example 2; FIG. 11 is an explanatory diagram of Example 3; FIG. 11 is an explanatory view of Example 3 as viewed from the distal direction; FIG. 10 is an explanatory diagram of the manufacturing method of Example 3; FIG. 11 is an explanatory diagram of Example 4; FIG. 11 is an explanatory diagram of Example 5; FIG. 11 is an explanatory view of Example 5 as viewed from the distal direction; FIG. 10 is an explanatory diagram of a manufacturing method of Example 5; FIG. 11 is an explanatory diagram of Example 6; FIG. 11 is an explanatory diagram of a manufacturing method of Example 6; FIG. 11 is an explanatory diagram of a usage state of Example 6; FIG. 11 is an explanatory diagram of a usage state of Example 7;

Although embodiments of the present invention will be described below with reference to the drawings, the present invention is not limited thereto.

This embodiment will be described with reference to FIGS. 1 to 3. FIG. A reamer 100 consists of an inserting portion 101 for inserting into a dental handpiece and a needle portion 102 insert-molded therein. The needle portion 102 is made of a stainless alloy with a total length of 25 mm, a tip diameter of 0.25 mm, and a taper angle of 2/100 (S1). By flattening, protrusions 104 are formed at both ends of the flat portion (S2). Since it is on both ends, a total of two projections 104 are provided.

According to the manufacturing method of steps (S1) to (S2), the reamer 100 having the two projections 104 on the tip portion 103 was obtained. When this is attached to the dental handpiece 200 and root canal treatment is performed, the treatment of digging and penetrating the root can be performed more accurately and quickly.

A state in which the reamer 100 is attached to the handpiece 200 is shown in FIG. The handpiece 200 is configured to be connected to the rotating shaft of an electric motor of a chair unit (not shown) and driven to rotate. The electric motor switch is a foot switch (not shown). This handpiece 200 has a vibration side housing 202 attached to a support portion 201 and a vibration cylinder 204 attached to the vibration side housing 202 . The vibrating cylinder 204 is located inside the vibration-side housing 202 and is provided so as to be able to vibrate in the axial direction (vertical direction in FIG. 3), which is the front-rear direction of the reamer 100. It is provided so as to be rotatable around an axis that is the direction of rotation. An extension of the rotating shaft of the electric motor of the chair unit is a rotating shaft 300 passing through the support portion 201 , and a pin 301 provided eccentrically at the tip of this rotating shaft 300 is positioned at the tip of the support portion 201 . ing.

Next, a vibrating cylinder mounting opening 203 is opened at the tip of the vibration-side casing 202, and a vibrating cylinder 204 is mounted therein. The pin 301 is inserted into a pin hole 205 provided at the rear end of the vibrating cylinder 204 . The rear end portion of the vibrating cylinder 204 has an insertion opening 207 for inserting the reamer 100 according to the manufacturing method of the first embodiment. The reamer 100 is configured so that it can be pushed in until the distal end of the inserting portion 101 of the reamer 100 comes into contact with the inner side of the needle passing hole 206 . The reamer 100 can be fixed by screwing a screw cap 208 into the insertion opening 207 threaded inside. Therefore, replacement of the reamer 100 is performed by attaching and detaching the screw lid 208 .

When the foot switch (not shown) is operated to rotate the electric motor, the pin 301 eccentrically attached to the tip of the rotary shaft 300 is engaged with the pin hole 205 provided in the side surface of the vibration cylinder 204. As a result, when the pin 301 performs circular motion, reciprocating motion is generated in the vibrating cylinder 204, and the vibrating cylinder 204 rotates about the above-described axis. As a result, the needle part 102 of the reamer 100 attached to the movable cylinder 204 reciprocates in the axial direction, which is the front-rear direction, and rotates around the axis, which is the rotation direction of the reamer 100, thereby excavating the root of the tooth and Penetration will be done.

This embodiment will be described with reference to FIGS. A reamer 105 is composed of an insertion portion 101 for insertion into a dental handpiece and a needle portion 102 insert-molded therein. The needle portion 102 was made of a stainless alloy with a total length of 25 mm, a tip diameter of 0.25 mm, and a taper angle of 2/100. ), a cut 107 crossing the circular surface is made in the tip portion 106 while applying ultrasonic vibration to the rotary cutting tool to form two projections with two-fold symmetry (S4).

Therefore, the two protrusions on both sides of the cut 107 made in the distal end portion 106 of the needle portion 102 serve as sites for treatment such as excavating or penetrating the root of the tooth. Conventional reamers and file needle tips do not have a structure like the two projections of this embodiment.

This embodiment will be described with reference to FIGS. The reamer 105 consists of an inserting portion 101 for inserting into a dental handpiece and a needle portion 109 insert-molded therein. The needle portion 109 is made of a nickel-titanium alloy with a total length of 22 mm, a tip diameter of 0.31 mm, and a taper angle of 2/100. (S5), by cutting out the troughs 111 at the four-fold symmetrical positions of the corners of this circular surface with a cutting tool of an automatic lathe, the troughs 111 between the troughs 111 are cut out. A peak portion 112 is formed at the position (S6). Further, a DLC (Diamond-Like Carbon) coating was applied to the cut tip portion 110 to form a plated surface (S7).

According to the manufacturing method of steps (S5) to (S7), the reamer 108 having four projections (mountain portions 112) on the tip portion 110 was obtained. If this is attached to the same dental handpiece 200 as that used in the first embodiment and root canal treatment is performed, the treatment of excavating or penetrating the root can be performed more accurately and quickly.

This embodiment will be described with reference to FIG. If the valleys 116 are formed at the positions of the four-fold symmetry in the tip portion 115 of the reamer 114 following the third embodiment, the peaks 117 are formed between the valleys 116 at the positions of the four-fold symmetry.

A first stepped portion 118 and a second stepped portion 119 are cut out from the peak portion 117 so as to be parallel to the circular cross section of the tip portion 115 . In this way, in addition to the projection by the four-rotationally symmetrical mountain portion 117, the mountain portion 117 is also provided with two-stage projections (stepped portions 118 and 119) in the axial direction of the needle portion, thereby digging or penetrating the tooth root. It has become more efficient to

A fifth embodiment will be described with reference to FIGS. 11 to 13. FIG. The reamer 120 consists of an inserting portion 101 for inserting into a dental handpiece and a needle portion 109 insert-molded therein. The needle portion 109 is made of a nickel-titanium alloy with a total length of 25 mm, a tip diameter of 0.25 mm, and a taper angle of 2/100. Using a tool (S8), cuts were made by laser engraving from the center to the outer edge of this circular surface so as to have three-fold symmetry to form star-shaped or Y-shaped cuts 122 ( S9).

Therefore, the three protrusions formed between the cuts 122 made in the distal end portion 121 of the needle portion 109 serve as sites for treatment such as excavating or penetrating the tooth root. Previous reamer and file needle tips did not have a configuration like the three prongs of this embodiment. Since fine engraving is possible with a laser engraving machine, it is possible to form finer projections with four-fold symmetry in which cuts are cross-shaped.

This embodiment will be described with reference to FIGS. 14 to 16. FIG. The reamer 123 consists of an inserting portion 101 for gripping and operating with the fingertips or inserting into a dental handpiece and a needle portion 124 insert-molded into this. As for the needle portion, a taper angle of 2/100, which is obtained by twisting three tapered metal needles made of stainless alloy, is used (S8). It is good to make a twisted needle with a total length of 25 mm at first, and then cut off 3 mm from the tip. The cutting is performed at a point where the circumscribed circle diameter of the tip is approximately 0.31 mm. By untwisting the distal end portion 125 of the needle portion 124 to form an untwisted portion 126, a three-fold symmetrical protrusion can be provided (S9). For example, if this is attached to a dental handpiece 400 as described below and root canal treatment is performed, the treatment of excavating or penetrating the root can be performed more accurately and quickly.

This handpiece differs from the handpiece 200 of the first embodiment in that the vibration cylinder 204 is attached to the vibration cylinder mounting opening 203 of the vibration side housing 202 in the handpiece 200, and the vibration cylinder 204 reciprocates in the vertical direction in the drawing. In this embodiment, the reamer 123 is provided movably, whereas in this embodiment, it is a rotating portion 400 for rotating the reamer 123 . FIG. 16 shows only the rotating portion 400. As shown in FIG.

That is, the rotating cylinder 401 built in the rotating part 400 has an insertion opening 405 for inserting the reamer 123 at its rear end portion. The reamer 123 is constructed so that it can be pulled out of the needle through hole 404 of the portion 400 and pushed until the tip of the inserting portion 101 of the reamer 123 comes into contact with the inside of the needle through hole 404 . Also, the reamer 123 can be fixed by pushing the push-in lid 406 into the insertion opening 405 . Accordingly, replacement of the reamer 123 is performed by attaching and detaching the screw cap 406 . A pin groove 402 is formed on the rear side surface of the rotating cylinder 401 over 360 degrees. A disk-shaped gear 403 is formed which meshes with the gear 303 provided. The wall surface on the rear side (upper side in FIG. 16) of the pin groove 402 is flat.

When the foot switch of the chair unit (not shown) is operated to rotate the electric motor, the gear 303 at the tip of the pin 302, which is an extension of the rotating shaft of the electric motor, moves to the disk of the pin groove 402 of the rotating cylinder 401. By engaging with the shaped gear 403, when the pin 302 performs circular motion, the rotary cylinder 401 rotates around the axis. As a result, the reamer 123 attached to the rotary cylinder 401 rotates about its axis, which is the direction of rotation, to excavate or penetrate the tooth root.

Since the needle part 124 of the reamer 123 is made by twisting three metal needles, there are cases where the action of guiding the drainage during treatment to the outside of the tooth root along this twist can be seen.

This embodiment will be described with reference to FIG. A feature of this embodiment is that a reamer 127 having only a needle portion 128 and having the same structure as the reamer 120 described in Embodiment 5 is inserted and fixed to the vane wheel 511 of the air turbine type hand piece 500. It is in.

That is, the needle portion 128 of the reamer 127 is made of a nickel-titanium alloy, and has a circular cross section (tip portion 121) perpendicular to the axis of the needle portion 128. Laser engraving is performed from the center to the outer edge of the needle portion 128 to form a three-dimensional cross section. A star-shaped or Y-shaped cut 122 with rotational symmetry is formed. Therefore, the three projections formed between the slits 122 made in the distal end portion 121 of the needle portion 128 serve as sites for treatment such as excavating or penetrating the tooth root. A carbon coating is applied to the tip 121 for laser engraving.

The air turbine type handpiece 500 rotates an impeller 511 inside the air turbine 510 at high speed by compressed air from a compressor, and the reamer 127 as a cutting tool attached coaxially to the impeller 511 removes tooth decay. It is an instrument that cuts and removes More specifically, a housing 501 having an air turbine 510 for rotating the reamer 127, and a handle-side housing containing an air supply passage 505 and a water supply passage 506 for the air turbine 510 attached to the housing 501. 502. An insertion hole 514 is provided inwardly from the lower surface of the impeller 511 so as to be coaxial with the rotating shaft 512 of the impeller 511, and the reamer 127 is inserted and fixed into the insertion hole 514. integrally established. A stepped portion 513 is formed at the boundary between the lower end portion of the impeller 511 and the reamer 127 . The vane wheel 511 made of nickel-titanium alloy integrally provided with the reamer 127 is rotatable within the housing 501 by means of the ball bearings 503 .

In the handle-side housing 502 , an air supply passage 505 to which an air supply pipe 508 is connected is provided toward an impeller 511 of an air turbine 510 . The air turbine 510 communicates with a spray port 507 for exhaust air, to which is connected a water supply passage 506 through which water is passed for cooling the teeth. A pipe 509 is connected. In other words, the exhaust air from the air turbine 510 joins the water from the water supply passage 506 , and mist of cooling water is discharged from the spray port 507 . In some cases, the exhaust from the air turbine 510 does not join the water supply passage 506, and a separate exhaust port is provided.

According to this embodiment, the reamer 127 has a cut 122 formed at the tip 121 of the needle portion 128, and when treatment is performed using the air turbine type handpiece 500 to which the reamer 127 is attached, the tooth root can be excavated or penetrated. It is possible to obtain the effect of being able to perform the treatment to be done more quickly.

When the reamer of the present invention is attached to a dental handpiece and root canal treatment is performed, there is an effect that the treatment of excavating or penetrating the root can be performed more accurately and quickly. This has reduced the burden on dentists and improved treatment techniques, thereby contributing to the development of industry. It should be noted that the present invention is not limited to the dimensions of each part of the above-described embodiment. Also, the dental handpiece is not limited to the above-described embodiment.

100: Reamer 101: Insertion part 102: Needle part 103: Tip part 104: Protrusion 105: Reamer 106: Tip part 107: Cut 108: Reamer 109: Needle part 110: Tip part 111: Valley part 112: Peak part 114: Reamer 115: tip portion 116: valley portion 117: peak portion 118: step portion 119: step portion 120: reamer 121: tip portion 122: cut 123: reamer 124: needle portion 125: tip portion 126: untie portion 127: reamer 128: Needle part 200: Hand piece 201: Support part 202: Vibration side housing 203: Vibration cylinder mounting opening 204: Vibration cylinder 205: Pin groove 206: Needle through hole 207: Insertion opening 208: Screw lid 300: Rotating shaft 301: Pin 302: Pin 303: Gear 400: Rotating part 401: Rotating cylinder 402: Pin groove 403: Disk-shaped gear 404: Needle through hole 405: Insertion port 406: Push-in lid 500: Handpiece 501: Housing 502: Handle-side housing 503: Ball bearing 504: Opening 505: Air supply passage 506: Water supply passage 507: Spray port 508: Air supply pipe 509: Water supply pipe 510: Air turbine 511: Impeller 512: Rotating shaft 513: Stepped portion 514: Insertion hole

Claims (8)

A reamer for use in a dental handpiece, characterized in that a plurality of protrusions are formed on the tip of a needle portion of the reamer. 2. The reamer for use in a dental handpiece according to claim 1, wherein four projections are formed at four-fold symmetrical positions on the distal end of the needle. 2. The reamer for use in a dental handpiece according to claim 1, wherein the needle portion is plated with good lubricity. The reamer used for a dental handpiece according to claim 3, wherein the plating is carbon coating or DLC (Diamond-Like Carbon) coating. A method for manufacturing a reamer used in a dental handpiece, wherein the protrusion is provided by cutting a tip of a needle portion of the reamer with a disk-shaped rotating blade. A method for manufacturing a reamer used in a dental handpiece, wherein the projection is provided by forming a valley portion at a corner portion of a tip portion of a needle portion of the reamer using a lathe. A method for manufacturing a reamer for use in a dental handpiece, wherein the projection is provided by cutting the tip of the needle portion of the reamer with a laser engraving machine. A dental handpiece with the reamer according to claim 1.

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