JP4179779B2 - Denture attachment - Google Patents

Description

[0001]
【Technical field】
The present invention relates to a denture attachment that removably fixes a denture to a keeper of a fixing abutment by magnetic attraction.
[0002]
[Prior art]
In dental treatment, various denture attachments using magnetic attraction have been proposed from the viewpoint of easy attachment and detachment of dentures.
For example, as shown in FIG. 9, a denture attachment 9 disclosed in Japanese Patent Laid-Open No. 9-224959 includes an implant 91 as a fixing support embedded in a jawbone, a keeper 93 attached thereto, The magnet structure 95 has an attracting surface 950 that is attracted to the attracted surface 930 by a magnetic attraction force.
[0003]
The implant 91 and the keeper 93 are joined by screwing a screw portion 931 provided in the keeper 93 into a screw hole portion 911 provided in the implant 91. At this time, the contact portions 912 and 932 of both members enhance the adhesion, and prevent foreign matters from entering the gap between the implant 91 and the keeper 93 and preventing them from becoming unclean.
[0004]
[Problems to be solved]
However, the maintenance of the bonding force is unstable simply by relying on screwing in the screw hole portion 911 and the screw portion 931, and there is a possibility that loosening may occur during use of the denture attachment. In addition, if the looseness occurs, the adhesiveness may be reduced at a stretch and the cleanliness may be reduced.
Therefore, conventionally, there has been a demand for the development of a denture attachment that can maintain the above-described bonding force and adhesion more stably when fixing a fixation support such as an implant and a keeper by a screwing method. .
[0005]
The present invention has been made in view of such conventional problems, and an object of the present invention is to provide a denture attachment capable of improving the bonding force and adhesion between a fixing support and a keeper.
[0006]
[Means for solving problems]
According to the first aspect of the present invention, there is provided a fixing abutment disposed on the jawbone side, a keeper supported by the fixing abutment, and an adsorption surface that is attracted to the attracted surface provided on the keeper by a magnetic attraction force. In a denture attachment comprising a magnet structure having
The keeper includes a main body provided integrally with the keeper itself and provided with the attracted surface, and a screw portion erected from the center of the back surface of the main body opposite to the attracted surface. A protruding ring portion protruding in the axial direction so as to form a ring-shaped groove between the conical tapered shaft portion provided at the base end of the screw portion and the tapered shaft portion at the outer peripheral portion of the back surface And
The projecting ring portion has an inclined shape whose diameter decreases at least as the outer peripheral surface goes to the tip, and a substantially flat contact portion is formed at the tip.
And the maximum outer diameter of the protruding ring part is larger than the outer diameter of the attracted surface of the main body part,
The fixing support includes a screw hole portion to which the screw portion of the keeper is screwed, and a conical tapered hole portion that is connected to the opening side of the screw hole portion and has substantially the same inclination angle as the taper shaft portion. And a substantially flat receiving surface portion provided at the outer peripheral end of the opening end portion for contacting the contact portion of the keeper,
When the screw part and the screw hole part are screwed together to join the keeper and the fixing support, first, there is a margin for tightening between the taper shaft part and the taper hole part. In this state, the abutting portion abuts on the receiving surface portion, and then the screwing of the keeper proceeds, so that axial stress is gradually applied to the abutting portion from the receiving surface portion. In a state where the tapered shaft portion and the tapered hole portion are firmly screwed together, the contact portion and the receiving surface portion come into contact with each other so that at least the protruding ring portion is elastically deformed in the axial direction. In addition, the denture attachment is configured in a shape with a tightening margin between the tapered shaft portion and the tapered hole portion in a state where the contact portion and the receiving surface portion are in contact with each other. (Claim 1).
[0007]
As described above, the denture attachment of the present invention is provided with the tapered shaft portion on the keeper and the protruding ring portion having the contact portion. On the other hand, the fixing support is provided with the tapered hole portion and the receiving surface portion. When the keeper and the fixing support are joined, as described above, the tapered shaft portion and the tapered hole portion are brought into close contact with each other, and the contact portion and the receiving surface portion are in contact with each other. A state in which the protruding ring portion is elastically deformed in the axial direction is obtained.
[0008]
Thereby, the joining force between the keeper and the fixing support is obtained by both the friction force between the tapered shaft portion and the tapered hole portion and the friction force between the contact portion and the receiving surface portion. In particular, by obtaining a frictional force due to the tapered shaft portion and the tapered hole portion, it is possible to exhibit a remarkably high joining force, that is, a screw loosening preventing force as compared with the conventional case.
[0009]
On the other hand, in this state, the projecting ring portion and the receiving surface portion come into contact with each other to obtain a close contact state.
That is, to obtain a dimensional accuracy that enables both the contact between the tapered shaft portion and the tapered hole portion and the contact between the contact portion and the receiving surface portion at the same time when screwing is performed. It is very difficult to make use of excellent processing technology. On the other hand, if it is assumed that the protruding ring part is elastically deformed to some extent when screwed, the processing accuracy of the keeper and the fixing support can be kept within a reasonable range, and two places as described above. Therefore, it is possible to easily obtain a joined state in which is firmly adhered.
[0010]
As a result, in the joined state, since the protruding ring portion is in an elastically deformed state, the contact between the contact portion and the receiving surface portion, the taper hole portion, and the taper shaft portion, which are the difficulties of the processing technique described above. Can be simultaneously performed at the time of screwing, and it is possible to achieve both an excellent screw loosening prevention force and a cleanliness preventing foreign matter from entering between the two.
[0011]
Therefore, according to this invention, the denture attachment which can improve the joining force and adhesiveness of a fixing stand and a keeper can be obtained.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
In the present invention, at least the tapered shaft portion and the abutting portion of the keeper and the tapered hole portion and the receiving surface portion of the fixing support are subjected to a surface treatment for improving wear resistance. (Claim 2).
In this case, the durability of the entire denture attachment can be improved by improving the wear resistance of the contact portion between the keeper and the fixing support.
[0013]
As the surface treatment in this case, various treatments usually performed to improve wear resistance can be performed. For example, coating such as TiN, diamond, N, Cr, ceramic, nitriding treatment, chromium treatment, etc. A surface treatment is mentioned.
Moreover, it is preferable to perform the same surface treatment on the attracted surface of the keeper and the attracted surface of the magnet structure. Thereby, the abrasion resistance at the time of attachment or detachment can be improved.
[0014]
Moreover, it is preferable that the opening end portion of the fixing support has an inclined surface that protrudes smoothly in the axial direction on the inner peripheral side of the receiving surface portion. In this case, it is possible to obtain a shape in which the inner surface side of the tapered hole portion of the fixing support is inserted in the groove portion inside the protruding ring portion, and the inner surface dimension of the tapered hole portion can be obtained. It is possible to increase the frictional force between the tapered hole portion and the tapered shaft portion.
[0015]
In addition, the contact portion of the protruding ring portion may include a first contact surface formed in a substantially horizontal shape and a second contact surface inclined so as to recede from the horizontal state on the inner peripheral side thereof. Preferred (claim 4). In this case, by applying the inclined second contact surface to the inner peripheral side of the receiving surface portion of the fixing abutment first, the stress directed radially outward with respect to the protruding ring portion In addition to the elastic deformation in the axial direction, radial elastic deformation can also be generated. Thereby, the joining stability between the keeper and the fixing support can be further enhanced.
[0016]
Moreover, it is preferable that the said receiving surface part of the said fixed support stand inclines so that it may retract | save as it goes outside. Also in this case, the contact portion of the keeper that is in contact with the pressure receiving surface receives a radially outward stress, which causes the elastic deformation in the radial direction in addition to the elastic deformation in the axial direction of the protruding ring portion. be able to. Thereby, the joining stability between the keeper and the fixing support can be further enhanced.
In this case, the inclined receiving surface portion and the abutting portion having the first abutting surface and the second abutting surface described above can be combined.
[0017]
The keeper is a member that is fixed to the upper part (on the magnet structure side) of the fixing support, forms a magnetic circuit together with the magnet structure, and fixes the denture to the fixing support. As a material for forming the keeper, various dental corrosion-resistant magnetic materials that have been conventionally used as a keeper for a denture attachment that uses a magnetic attractive force can be used. In particular, it is desirable to use a magnetic material having a saturation magnetic flux density of 1.3 T or more and a magnetic permeability of 3000 or more. Examples of the magnetic material having such characteristics include iron, chromium, molybdenum alloy, 19Cr-2Mo-0.2Ti steel. , 17Cr-2Mo-0.2Ti steel and other soft magnetic stainless steel.
[0018]
The magnet structure is a member that forms a magnetic circuit together with the keeper and fixes the denture to the fixing abutment. This magnet structure includes a magnet body. However, this magnet body is not particularly limited, and various magnetic bodies that have been conventionally used as a magnet body of a denture attachment that uses magnetic attraction force can be used. Can be used. In particular, it is desirable to use a magnetic material having a high energy product. Specifically, it is practically desirable to use a magnetic material having an energy product of 2388 kJ / m ³ or more. Examples of such a magnetic material include Nd—Fe—B and Sm—Co rare earth magnets.
[0019]
【Example】
(Example 1)
As shown in FIG. 1, the denture attachment 1 according to the embodiment of the present invention is provided with a fixing base 10 disposed on the jawbone side, a keeper 3 supported by the fixing base 10, and the keeper 3. It is a denture attachment which consists of the magnet structure 5 which has the attracting surface 51 attracted | sucked to the attracted surface 31 by magnetic attraction force.
[0020]
The keeper 3 includes a main body portion 30 provided with a suction surface 31, a screw portion 33 erected from the center of the back surface of the main body portion 30 opposite to the suction surface 31, and a base of the screw portion 33. A conical tapered shaft portion 35 provided at the end, and a projecting ring portion 37 projecting in the axial direction so as to form a ring-shaped groove between the outer peripheral portion of the back surface and the tapered shaft portion 35 .
The projecting ring portion 37 has an inclined shape that decreases in diameter toward at least the outer peripheral surface 372 toward the tip, and a substantially flat contact portion 375 is formed at the tip.
[0021]
The fixing support 10 includes a screw hole portion 13 into which the screw portion 33 of the keeper 3 is screwed, and a cone having the same inclination angle as that of the tapered shaft portion 35 provided on the opening side of the screw hole portion 13. A tapered hole portion 15 and a substantially flat receiving surface portion 17 provided at the outer peripheral end of the opening end portion for contacting the contact portion 375 of the keeper.
[0022]
When the screw part 33 and the screw hole part 13 are screwed together to join the keeper 3 and the fixing support 10, the taper shaft part 35 and the taper hole part 15 are in close contact with each other. At the same time, the contact portion 375 and the receiving surface portion 17 are in contact with each other so that at least the protruding ring portion 37 is elastically deformed in the axial direction.
This will be described in further detail below.
[0023]
As shown in FIG. 1, the fixing support 10 is a so-called implant, and has a screw thread on a side surface (not shown). The screw hole portion 13 and the taper hole portion 15 are provided at the upper end thereof to be opened. ing.
Further, in this example, the opening end portion of the fixing support 10 is provided with the inclined surface 16 that smoothly protrudes in the axial direction on the inner peripheral side of the receiving surface portion 17.
In this example, the inclination angle α1 of the tapered hole portion 15 with respect to the axial direction is set to 8 °. Further, the receiving surface portion 17 at the opening end portion is provided substantially horizontally.
Further, the fixing support 10 of this example is made of Ti.
[0024]
As shown in the figure, the keeper 3 has the suction surface 31 of the main body 30 formed horizontally. As shown in FIGS. 1 and 5, flat cutout portions 318 for engaging a tool (not shown) when screwing the keeper 3 are provided at four locations on the outer peripheral surface of the main body portion.
Further, the projecting ring portion 37 is disposed on the back surface of the main body portion 30 so that the taper shaft portion 35 and the screw portion 33 are connected to each other, and a round bottom groove portion 36 is formed between the taper shaft portion 35 and the taper shaft portion 35. ing.
[0025]
In this example, the inner peripheral surface 371 of the protruding ring portion 37 is provided such that the angle γ with respect to the axial direction is inclined by 40 °, and the outer peripheral surface 372 is inclined by 40 ° with respect to the axial direction.
A flat contact portion 375 is provided at the tip portion sandwiched between the inner peripheral surface 371 and the outer peripheral surface 372 of the protruding ring portion 37. In this example, they are arranged substantially horizontally. .
[0026]
The keeper 3 is made of 19Cr-2Mo-0.2Ti. In this example, the taper shaft portion 35 of the keeper 3, the inner surface (inner peripheral surface 371) of the contact portion 375, and the attracted surface 31 are subjected to a surface treatment for improving wear resistance. Specifically, a film made of TiN having a thickness of about 2 μm was formed by ion plating.
[0027]
As shown in FIG. 1, the magnet structure 5 includes a first yoke 52 having a magnet body 55 having N and S poles opposite to each other in the tooth height direction, and a recess 59 for housing the magnet body 55. A second yoke 53 that is disposed in the opening of the first yoke 52 and seals the magnet body 55 and faces the keeper 3, and a non-position located at the boundary between the first yoke 52 and the second yoke 53. And a magnetic part 54.
In the magnet structure 5, the attracting surface 51 formed by the first yoke 52, the second yoke 53, and the nonmagnetic portion 54 has a horizontal plane shape that is type-symmetric with the attracted surface 31 of the keeper 3. is doing.
[0028]
Further, the adsorption surface 51 of the magnet structure 5 is subjected to a surface treatment with a TiN film in order to improve wear resistance.
The magnet structure 5 is an Nd rare earth magnet. For the first yoke 52 and the second yoke 53, 19Cr-2Mo-0.2Ti magnetic stainless steel was used.
[0029]
Next, when using the denture attachment 1 having the above structure, first, the fixing abutment 10 is embedded in a jawbone (not shown). Next, the keeper 3 is screwed to the fixing support 10.
At this time, in this example, the keeper 3 and the fixing support 10 are processed so as to have a dimensional relationship that provides the following effects.
[0030]
That is, as shown in FIG. 2, by screwing the keeper 3 together with the screw portion 33 of the keeper 3 and the fixing base 10 screw hole 13, the taper shaft portion 35 and the contact portion 375 of the keeper 3 are brought into contact with each other. , The taper hole portion 15 and the receiving surface portion 17 of the fixing base 10 approach each other.
[0031]
As shown in FIG. 3, the contact portion 375 contacts the receiving surface portion 17 with a certain amount of tightening margin between the tapered shaft portion 35 and the tapered hole portion 15 .
[0032]
Next, as shown in FIG. 4, as the keeper 3 is screwed in, stress in the axial direction mainly from the receiving surface portion 17 is gradually applied to the contact portion 375, and the tapered shaft portion 35 and the tapered portion 35 are tapered. In a state where the hole 15 is firmly screwed, a state where the protruding ring portion 37 is elastically deformed at least in the axial direction is obtained.
[0033]
As described above, the denture attachment 1 of this example brings the tapered shaft portion 35 and the tapered hole portion 15 into close contact with each other as described above when the keeper 3 and the fixing support 10 are joined. The contact portion 375 and the receiving surface portion 17 are in contact with each other, so that at least the protruding ring portion 37 is elastically deformed in the axial direction.
[0034]
Thereby, the joining force between the keeper 3 and the fixing support 10 is obtained by both the frictional force between the tapered shaft portion 35 and the tapered hole portion 15 and the frictional force between the contact portion 375 and the receiving surface portion 17. . And especially by obtaining the frictional force by the taper shaft part 35 and the taper hole part 15, a remarkably high joining force, that is, a screw loosening prevention force can be exhibited as compared with the prior art.
[0035]
As a result, in the joined state, the protruding ring portion 37 is in an elastically deformed state, so that the contact between the contact portion 375 and the receiving surface portion 17, which is a difficulty in the processing technique, and the tapered hole portion 15. And the taper shaft portion 35 can be brought into contact with each other at the same time during screwing, and both an excellent screw loosening prevention force and cleanliness preventing foreign matter from entering between the two can be achieved.
[0036]
(Example 2)
In this example, as shown in FIG. 6, a keeper 3 and a magnet structure 5 having a slightly different configuration from those of the first embodiment are used.
Specifically, as shown in the figure, the keeper 3 has its attracted surface 31 formed into a convex spherical shape having a curvature radius of 8 mm. On the other hand, the attracting surface 51 of the magnet structure 5 is formed in a concave spherical shape that is symmetrical with the attracted surface 31 of the keeper 3.
Other structures are substantially the same as those of the denture attachment 1 of the first embodiment, and the shapes and dimensions of the tapered shaft portion 35 and the contact portion 375 in the keeper and the tapered hole portion 15 and the receiving surface portion 17 in the fixing base 10 are also implemented. Same as Example 1.
[0037]
Also in this example, when the keeper 3 and the fixing support 10 are joined, the taper shaft portion 35 and the taper hole portion 15 are in close contact with each other and the abutment is performed as in the first embodiment. The state where the part 375 and the receiving surface part 17 abut and at least the protruding ring part 37 is elastically deformed in the axial direction is obtained. Therefore, it is possible to obtain a very excellent bonding force and adhesion.
[0038]
(Example 3)
In this example, as shown in FIG. 7, the shape of the contact portion 375 of the keeper 3 in the first embodiment is changed.
That is, the contact portion 375 of the projecting ring portion 37 of the present example includes a first contact surface 376 formed in a substantially horizontal shape and a second contact surface 377 inclined so as to retreat from the horizontal state on the inner peripheral side thereof. And more composed.
[0039]
In this case, the inclined second abutting surface 377 is first brought into contact with the inclined surface 16 on the inner peripheral side of the receiving surface portion 17 of the fixing support 10 so that the protruding ring portion 37 is brought into contact with the inclined abutting surface 16. Stress is applied outward in the radial direction, and in addition to elastic deformation in the axial direction, elastic deformation in the radial direction can also be generated. Thereby, the joining stability of the keeper 3 and the fixing support 10 can be further improved.
In other respects, the same effects as those of the first embodiment can be obtained.
[0040]
Example 4
In this example, as shown in FIG. 8, the shape of the receiving surface portion 17 of the fixing base 10 in the first embodiment is changed.
That is, the receiving surface portion 17 of the fixing support 10 of this example is inclined so as to recede as it goes outward. The specific inclination angle β was about 30 ° with respect to the horizontal direction.
[0041]
In this case, the abutting portion 375 of the keeper 3 that abuts against the pressure receiving surface 17 receives a radially outward stress, and in addition to the 17-axis elastic deformation of the protruding ring portion, the elastic deformation in the radial direction. Can also be produced. Thereby, the joining stability between the keeper 3 and the fixing support 10 can be further enhanced.
In addition, the inclined receiving surface part 17 in this case and the contact part which has the 1st contact surface 376 and the 2nd contact surface 377 of Example 3 mentioned above can also be combined.
In other respects, the same effects as those of the first embodiment can be obtained.
[Brief description of the drawings]
FIG. 1 is an explanatory view showing a configuration of a denture attachment in Example 1. FIG.
FIG. 2 is an explanatory diagram illustrating an initial stage of a joining operation between a keeper and a fixing support in the first embodiment.
FIG. 3 is an explanatory diagram showing a moment when a contact portion comes into contact with a receiving surface portion when the keeper and the fixing support are joined in the first embodiment.
FIG. 4 is an explanatory view showing a state in which the joining of the keeper and the fixing support is completed in the first embodiment.
FIG. 5 is a plan view of a keeper in the first embodiment.
6 is an explanatory view showing the configuration of a denture attachment in Example 2. FIG.
7 is an explanatory view showing the shape of a keeper contact portion in Embodiment 3. FIG.
FIG. 8 is an explanatory diagram showing the shape of the receiving surface portion of the fixing support in the fourth embodiment.
FIG. 9 is an explanatory view showing a configuration of a denture attachment in a conventional example.
[Explanation of symbols]
1. . . Denture attachment,
10. . . Fixing abutment,
13. . . Screw holes,
15. . . Taper hole,
17. . . Receiving surface,
3. . . Keeper,
30. . . Body part,
31. . . Adsorbed surface,
33. . . Thread,
35. . . Taper shaft,
37. . . Protruding ring part,
375. . . Abutting part,
5. . . Magnet structure,
51. . . Adsorption surface,

Claims (5)

A denture attachment comprising a fixing abutment disposed on the jawbone side, a keeper supported by the fixing abutment, and a magnet structure having an attracting surface that is attracted to the attracted surface provided on the keeper by a magnetic attraction force In
The keeper includes a main body provided integrally with the keeper itself and provided with the attracted surface, and a screw portion erected from the center of the back surface of the main body opposite to the attracted surface. A protruding ring portion protruding in the axial direction so as to form a ring-shaped groove between the conical tapered shaft portion provided at the base end of the screw portion and the tapered shaft portion at the outer peripheral portion of the back surface And
The projecting ring portion has an inclined shape with a diameter decreasing toward the tip at least on the outer peripheral surface, and a substantially flat contact portion is formed at the tip.
And the maximum outer diameter of the protruding ring part is larger than the outer diameter of the attracted surface of the main body part,
The fixing support includes a screw hole portion to which the screw portion of the keeper is screwed, and a conical tapered hole portion that is connected to the opening side of the screw hole portion and has substantially the same inclination angle as the taper shaft portion. And a substantially flat receiving surface portion provided at the outer peripheral end of the opening end portion for contacting the contact portion of the keeper,
When the screw part and the screw hole part are screwed together to join the keeper and the fixing support, first, there is a margin for tightening between the taper shaft part and the taper hole part. In this state, the abutting portion comes into contact with the receiving surface portion, and then the screwing of the keeper proceeds, so that axial stress is gradually applied to the contacting portion from the receiving surface portion. In a state where the tapered shaft portion and the tapered hole portion are firmly screwed together, the contact portion and the receiving surface portion come into contact with each other so that at least the protruding ring portion is elastically deformed in the axial direction. Further, the denture attachment is configured in a shape having a tightening margin between the tapered shaft portion and the tapered hole portion in a state where the contact portion and the receiving surface portion are in contact with each other.   The surface treatment for improving wear resistance is performed on at least the tapered shaft portion and the contact portion of the keeper and the tapered hole portion and the receiving surface portion of the fixing support. Denture attachment characterized by   The denture attachment according to claim 1 or 2, wherein the opening end portion of the fixing support has an inclined surface smoothly projecting in the axial direction on the inner peripheral side of the receiving surface portion. .   The contact portion of the protruding ring portion according to any one of claims 1 to 3, wherein the contact portion of the projecting ring portion is inclined so as to recede from a horizontal state on a first contact surface formed in a substantially horizontal shape and an inner peripheral side thereof A denture attachment comprising the second contact surface.   The denture attachment according to any one of claims 1 to 4, wherein the receiving surface portion of the fixing abutment is inclined so as to recede toward the outside.

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