JPH11299807A - Keeper for denture attachment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a keeper for a denture attachment for dissolving the problem of the disturbance of a diagnosis or the like by the keeper composed of a soft magnetic material at the time of an MRI diagnosis or the like and facilitating the attachment of the keeper after the MRI diagnosis or the like by facilitating the detachment of the keeper without lowering the magnetic attraction performance of a magnet structure body and the keeper composed of the soft magnetic material. SOLUTION: This keeper is constituted of a keeper main body 11 composed of a ring-like corrosion resistant soft magnetic material and joined to a root surface plate 3, provided with an R part 11a on an outer peripheral part and fixable on an inner peripheral side by a T-shaped screw, a holding plate 12 composed of a corrosion resistant non-magnetic material abutted to the root surface plate side of the keeper main body 11 and cast and joined to the root surface plate 3 for attachably and detachably screwing the keeper main body 11 by the T-shaped screw and the T-shaped screw composed of the corrosion resistant non-magnetic material for fixing the keeper main body 11 to the holding plate 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a keeper that is a component of a denture attachment utilizing magnetic attraction and is fixed to a root-side root plate.

[0002]

2. Description of the Related Art Conventionally, a keeper 101, which is one element of a denture attachment utilizing magnetic attraction, is usually fixed to a root plate 103 by casting. As shown in FIG. 6, a root plate 103 is embedded in the root portion 106, and a keeper 101 is embedded and fixed above the root plate 103. The keeper 101 is cast into contact with a root plate 103 buried above the remaining root portion 106 to restore the root portion 106, and the denture base 10 in which the magnetic body 103 is embedded.
4 and serves to fix the denture 105.

As shown in FIG. 6, the keeper 101 is buried and fixed above the root plate 103 by casting.
It is difficult to remove only one. On the other hand, Keeper 1
No. 01 has a problem that images are disturbed at the time of diagnosis of a brain or the like by MRI (nuclear magnetic resonance) because the keeper 101 itself is formed of a magnetic material. Therefore, some structures have been proposed in which the keeper 101 can be removed from the root plate 103.

For example, as shown in FIG. 4, a keeper of a dental magnetic attachment proposed in Japanese Patent Application Laid-Open No. 7-323037 discloses a tooth root 2 made of a corrosion-resistant non-magnetic material.
The keeper 210 is integrally buried in the end of the root member 203 by casting, and the keeper 210 includes a keeper body 210a made of a magnetic material and a keeper support 210b made of a non-magnetic pair. 210
a (for example, with male screw 211) and keeper support 2
10b (for example, there is a female screw 212) is detachable (for example, there is a male screw 211 and a female screw 212), and at the time of MRI diagnosis or the like, the male screw 211 and the female screw 212 are provided.
The keeper body 210a is detached from the keeper support 210b by releasing the screwing of the keeper, thereby preventing an adverse effect on the result of the MRI diagnosis or the like.

In a root member for stabilizing a denture proposed in Japanese Patent Application Laid-Open No. 8-646, as shown in FIG. 5, a root member main body 301 made of a non-magnetic material is formed in a substantially mushroom shape. A holding member 3 made of a non-magnetic material and formed with a female screw is provided in a recess at the end of the main body on the side of the permanent magnet assembly.
10 is a cast-in shape which is arranged so that the bottom surface of the holding member 310 is at a position 0.3 mm or more higher than the lower surface 322 of the boss portion of the main body 301, and is a soft magnetic holding plate having a flat head screw shape 321 with a head. 303 is the main body 3
01 so as to protrude from the end surface of the holding member 310.
When the magnetic properties such as the use of MRI are likely to be affected, the holding plate can be easily removed by screws.

[0006]

However, the conventional keeper and denture stabilizing root surface member described above have the following problems. That is, JP-A-7-323037
In the figure, the columnar keeper 210 is divided into a magnetic disk-shaped keeper main body 210a having a male screw 211 and a ring-shaped keeper support 210b having a female screw 212, and the root surface member 203 is made using the action of the screw. The keeper main body 210a is detachable from the keeper support 210b embedded and fixed in the keeper. However, the keeper main body 210a and the keeper support 210b are connected to each other through a male screw 211 and a female screw 212 in a columnar shape. Since the keeper 210 is integrally buried and fixed by casting, the root surface member 2
It is difficult to rotate and remove only the keeper body 210a constrained by the keeper body 03. Further, when the keeper body 210a is mounted on the keeper support again, it is also difficult to rotate and insert the keeper body 210a on the inner peripheral side of the root surface member 203. Further, the male screw 211 is inferior in strength due to the magnetic material, and the inconvenience that the screw portion is broken easily occurs.

[0007] Next, in Japanese Patent Application Laid-Open No. 8-646, a holding member 310 having an internal thread and a flat head screw shape 321 with a head are disclosed.
The holding plate 303 fixed to the holding member 310 is made detachable from the holding member 310 by using the action of a screw, and is divided into a T-shaped soft magnetic holding plate 303 having In order to secure the size of the soft magnetic holding plate required for the embedded permanent magnet assembly to be magnetically attracted, the head of the holding plate 303 is moved from the root surface member 301 so as to match the size of the holding member 310. Is protruded, so that a gap is generated between the permanent magnet assembly and the soft magnetic holding plate 303, which is likely to cause inconvenience.
In addition, the male screw 311 is inferior in strength due to a magnetic material, and the inconvenience that the screw part is broken easily occurs.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems in the prior art, and it is an object of the present invention to facilitate removal of a keeper without deteriorating magnetic attraction performance between a magnet structure and a keeper made of a soft magnetic material. Accordingly, an object of the present invention is to solve the problem of image disorder due to a keeper made of a soft magnetic material in MRI diagnosis and the like, and to provide a keeper for a denture attachment that makes it easy to mount the keeper again after the MRI diagnosis and the like. .

[0009]

In order to achieve the above object, the present inventors have proposed a magnetic member having a magnetic attraction between a magnet structure and a magnetically attracting keeper and a screw member which allows the keeper to be easily detached and attached repeatedly. As a result of diligent research, we found that the keeper did not decrease magnetic attraction even if it had a ring shape with a hole in the center, and from that knowledge, the screw member was a T-shaped screw with a male screw made of a non-magnetic material. The present invention has been completed by finding that when the strength is improved, the breakage of the screw portion is reduced.

The present invention relates to a denture attachment comprising a magnet structure held in a denture base and a keeper fixed in a root plate buried in the root portion, which is cast-contacted to the root plate and has an R portion on the outer peripheral side. A keeper body made of a corrosion-resistant magnetic material having a ring shape that can be fixed to the inner peripheral side with a T-shaped screw; and a keeper body abutting on a root face plate side of the keeper body and being cast-contacted with the root face plate to form the T-shaped keeper body. A holding plate made of a corrosion-resistant non-magnetic material having a female screw for detachably screwing with a male screw of the screw, and a T-shaped screw made of a corrosion-resistant non-magnetic material for screwing and fixing the keeper body to the holding plate It will be.

[0011] The keeper body may have one or more depressions or one or more dish-shaped recesses on the casting contact surface from the root of the ring-shaped keeper body. The outer peripheral portion of the ring-shaped keeper main body adjacent to the magnet structure, which is 0.1 to 0.3 mm, preferably has a cylindrical shape. The holding plate may have a holder made of a corrosion-resistant non-magnetic material so that the casting operation can be performed easily and reliably when the keeper is cast-welded to the root plate. The corrosion-resistant non-magnetic material of the T-shaped screw, the holding plate and the holder is more preferably a high-strength material such as a Ti alloy.

That is, the keeper of the present invention comprises a keeper body, a holding plate, and a T-shaped screw. The keeper body is made of a corrosion-resistant magnetic material, and has a ring shape having an opening at the center thereof so that a T-shaped screw for screwing the keeper body to the holding plate can be inserted. The inner peripheral side of the ring has a through hole through which the threaded portion of the T-shaped screw penetrates, and a support portion that supports the seating surface of the head continuously with the through hole. And a continuous hole. Next, from the outer peripheral side of the ring, the side opposite to the magnetically attracted surface with the magnet structure (hereinafter referred to as the lower side).
Is cast-contacted to the root plate except for the portion that contacts the holding plate. The shape from the outer peripheral side to the lower side of the ring to be cast is an R shape. With the R-shape, the keeper body embedded and fixed in the root plate after casting can be easily removed from the root plate after removing the T-shaped screw fixing the keeper body to the holding plate.

Further, by providing one or a plurality of depressions or one or a plurality of dish-shaped recesses on the lower surface side of the keeper body, the keeper body can be prevented from rotating on the root plate. When inserting the keeper body again after MRI diagnosis or the like, it becomes easy to fix the keeper body to the root plate by rotating the T-shaped screw.

Further, when the keeper body embedded and fixed to the root plate after casting is easily dropped off from the root plate,
A ring-shaped keeper body, which is a part of the R shape on the ring outer peripheral side, has a cylindrical outer peripheral portion of 0.1 to 0.3 mm adjacent to the magnet structure. That is, the outer peripheral side of the keeper main body exerts a restraining force due to the contact portion with the inner peripheral side of the upper part of the root plate.

As the corrosion resistant magnetic material of the keeper body, 19Cr-2Mo-Ti steel, 13Cr-2Mo-T
i steel and 17Cr-2Mo-Ti steel. Further, surface treatment such as plating may be performed to further improve the corrosion resistance of these materials.

The holding plate is made of a corrosion-resistant non-magnetic material, is fixedly screwed to the lower surface side of the keeper body with a T-shaped screw, abuts on the root plate side of the keeper body, and is cast-contacted with the root plate. The holding plate has a female screw. In addition, when the holding plate is cast-joined to the root plate in a mold, a corrosion-resistant non-magnetic material for easily and reliably performing the work of casting the keeper consisting of the keeper body, the holding plate and the T-shaped screw at a predetermined position. May be provided on the outer peripheral side of the holding plate.

The T-shaped screw is made of a corrosion-resistant non-magnetic material, and has a slit on its upper surface for screwing to a holding plate.

As a corrosion-resistant non-magnetic material of the holding plate and the T-shaped screw, there is a non-magnetic stainless steel such as SUS316. In order to further improve the strength, Ti
Alloys and the like are good.

[0019]

Next, the operation of the present invention will be described. In the keeper of the present invention, the keeper body and the holding plate are integrated by screwing and fixing with a T-shaped screw and embedded and fixed in the root plate. On the other hand, when it is necessary to remove the keeper body made of a magnetic material from the root plate for MRI diagnosis or the like, the keeper body can be easily removed from the root plate. That is, after inserting a screwdriver into the slit of the T-shaped screw fixing the keeper main body, turning it in a predetermined direction to release the screw fixing with the holding plate, and floating and removing the T-shaped screw from the keeper main body, The T-shaped screw can be mechanically removed without breaking. Furthermore, MR
There is an effect that the keeper body can be easily inserted after the I diagnosis or the like is completed.

[0020]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing a keeper for a denture attachment according to the present invention. A denture attachment keeper according to an embodiment of the present invention will be described with reference to FIGS. 1, 2, and 3. FIG. FIG. 1 is a cross-sectional view in which a keeper for a denture attachment is mounted in a tooth cavity, FIG. 2 is a longitudinal sectional view of a main part in which a keeper is embedded and fixed in a root plate, and FIG. 3 is an exploded view of the keeper.

In FIG. 1, a keeper 1 is made of a corrosion-resistant soft magnetic material AUM20 (19Cr-2 manufactured by Aichi Steel Co., Ltd.).
Ring-shaped keeper body 11 made of Mo-Ti steel)
, A holding plate 12 with a holder 12b made of a Ti alloy (Ti-6Al-4V), and a T-shaped screw 13 made of a Ti alloy. The root plate is buried in the root portion 5, and the magnet structure 2 magnetically attracted to the keeper 1 is buried in the denture base 4.

The keeper body 11 is provided with an R portion 11a from the outer peripheral side to the lower side of the ring so that the keeper body 11 can be easily detached from the root plate 3, so that the keeper body does not rotate during attachment and detachment or during use. 11b on the lower side
Are provided at two locations. In addition, T
A support portion 11c for supporting the head seat surface 13a of the V-shaped screw 13 is provided.

The holding plate 12 is formed with a female screw 12b into which a male screw 13b of a T-shaped screw 13 for fixing the keeper body 11 can be screwed, so that the keeper can be easily and reliably cast-joined to the root plate. As described above, the holder 12b is attached to the upper portion of the side surface of the holding plate by laser welding.

The T-shaped screw 13 is provided with a slit on the upper surface of the head for screwing to the holding plate 12, so that the tip of the driver can be inserted and rotated.

FIG. 1 shows that the magnetic attraction between the magnet structure 2 and the keeper 1 is not different from that of the conventional disk-shaped keeper even when the keeper body 11 is formed in a ring shape. That is, the magnet structure 2 is composed of a magnet 21 made of a sintered NdFeB magnet and a case 22 made of a corrosion-resistant soft magnetic material AUM20.
The magnetic flux flow 23 from 1 flows through the outer periphery of the case 22 to the keeper main body 11 and forms a magnetic flux flow 23 returning from the keeper main body 11 to the magnet 21. Therefore, even if the central portion of the keeper body 11 is formed as an opening, the influence on the magnetic attraction is small.

In FIG. 2, the keeper body 11 is an AUM
The ring flat portion has a diameter of 4.0 mm, the cylindrical portion has a diameter of 0.2 mm, the R portion has a radius of 0.6 mm, and the depression has a diameter of 0.5 mm and a depth of 0.25 mm. A hole having a diameter of 1.6 mm and a depth of 0.5 mm into which the T-shaped screw head 13a can be inserted so that the T-shaped screw 13 can be inserted into the keeper body 11 has a male screw 13b formed concentrically with the hole. 0.8mm diameter so that the part can be inserted
Holes are machined.

The holding plate 12 is made of a Ti alloy and has a diameter of 1.
A female screw 12a is machined at 6 mm, a height of 1.0 mm, an inner circumference of M0.8, and a pitch of 0.2 mm. A holder having a diameter of 0.5 mm and a length of 15 mm is joined to the outer periphery by laser welding.

The T-shaped screw 13 is made of a Ti alloy, the head 13a has a diameter of 1.6 mm, a thickness of 0.5 mm, a male screw 13b of M0.8, a pitch of 0.2 mm and a length of 1. 3 mm. A slit having a width of 0.3 mm and a depth of 0.3 mm is cut in the flat portion 13c.

The keeper body 11 is set on the holding plate 12 with T-shaped screws 13 and integrated with the root plate 3 by casting. Here, as shown in FIG. 3, a T-shaped screw 13 for fixing the keeper body 11 to the holding plate 12 is provided.
Can be freely attached to and detached from the holding plate 12,
The keeper body 11 can be freely attached to and detached from the root plate 3. In addition, the size of the magnet structure 2 and the size of the keeper main body 11 can be made the same, and there is no inconvenience and no decrease in the magnetic attraction. Further, since the holding plate 12 and the T-shaped screw 13 are made of a non-magnetic material having the same strength, there is no inconvenience that the screw portion is broken.

[0030]

As described above, according to the present invention, the keeper body is fixed to the holding plate and the root plate through the screwing of the T-shaped screw and the holding plate. Keeper body can be removed, and MRI
Thus, it is possible to provide a denture attachment keeper that can be easily and reliably and repeatedly attached after the completion of the diagnosis.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a denture attachment keeper installed in a tooth cavity in an embodiment of the present invention.

FIG. 2 is a longitudinal sectional view of a main part in which a keeper is buried and fixed to a root plate in an embodiment of the present invention.

FIG. 3 is an exploded view of a keeper in the embodiment of the present invention.

FIG. 4 is a cross-sectional view showing a conventional denture attachment keeper mounted in a tooth cavity.

FIG. 5 is a longitudinal sectional view of a main part of a conventional keeper for a denture attachment.

FIG. 6 is a vertical sectional view of a main part of a conventional keeper for a denture attachment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Keeper 11 Keeper main body 11a R part of keeper main body 11b Depression of keeper main body 11c Supporter of keeper main body 11d Keeper main body cylindrical part 12 Holding plate 12a Female screw of holding plate 12b Holder of holding plate 13 T-shaped screw 13a T-shaped screw 13b Male screw of T-shaped screw 13c Slit of T-shaped screw 2 Magnet structure 21 Magnet 22 Case 23 Magnetic flux flow 3 Root plate 4 Denture base 5 Root portion

Claims (4)

[Claims] 1. A denture attachment comprising a magnet structure held in a denture base and a keeper fixed in a root plate embedded in a root portion, wherein the denture attachment is cast-contacted to the root plate and has an R portion on an outer peripheral side. And T on the inner circumference
A ring-shaped keeper body made of a corrosion-resistant magnetic material that can be fixed by a V-shaped screw; and a keeper body that comes into contact with a root plate side of the keeper body and is cast into contact with the root plate. The keeper body is detachably screwed by a T-shaped male screw. A holding plate made of a corrosion-resistant non-magnetic material having a female screw for attachment, and a T-shaped screw made of a corrosion-resistant non-magnetic material for fixing the keeper body to the holding plate, for a denture attachment. keeper. 2. A keeper for a denture attachment according to claim 1, wherein said ring-shaped keeper body has one or more recesses in a casting contact surface. 3. The keeper for a denture attachment according to claim 1, wherein the holding plate has a holder made of a corrosion-resistant non-magnetic material. 4. The keeper for a denture attachment according to claim 1, wherein the corrosion-resistant non-magnetic material is made of a high-strength material such as a Ti alloy.