WO1993025159A1 - Attachment for false tooth - Google Patents

Abstract

The main body (2) of an attachment according to the present invention comprises: a pair of yokes (21, 22) made of a corrosion-resistant soft magnetic alloy, which are provided on the side of a keeper (1) with a spacer (23) interposed therebetween; magnets (24, 25) provided for forming a longitudinal magnetic field with respect to the keeper (1), with an N pole opposed to one (21) of the yokes and an S pole opposed to the other (22) of the yokes; and a cap (27) crowned, for integrally surrounding the magnets (24, 25), the pair of yokes (21, 22) and the spacer (23) except for on the keeper's side. With the formation of the magnetic field, a high attracting force is generated between the yokes (21, 22) and the keeper (1). With the provision of the magnets (24, 25) as described above, high attracting force is secured, and, in addition, it becomes possible to shorten the main body (2) of the attachment in the direction of height, thus making the attachment more compact.

Description

 Description Denture technology Technical field

 The present invention relates to a denture attachment in which a denture is detachably attached to a root portion using magnetic attraction. Background art

 2. Description of the Related Art Conventionally, dentures using magnetic attraction have been known in which a denture portion is provided so as to face a root plate made of a magnetic material implanted on the top of a tooth root in an alveolar tooth (Japanese Patent Application Laid-Open No. H10-28139). 6 2—2 3 1 6 5 3 Publication). The denture portion here has a denture base made of plastic or the like, and a magnetic body is embedded in the denture base at a position facing the root plate. This magnetic body is a magnet in which a magnet is arranged in a stainless steel case. As the magnet, an Sm (samarium) -Co (cobalt) -based rare earth magnet having a strong magnetic force is used.

 However, the conventional magnet as described above has an attraction force of about 200 gf to 30 Ogf, and it is difficult to mechanically hold the magnet between spring teeth, which has been frequently used in the past, with a spring. Significantly lower than Ogf or higher.

In addition, since magnets are easily corroded in the oral cavity, if a rare earth magnet is exposed in the oral cavity, it will be attracted by the magnets The force diminished quickly and there were safety issues. On the other hand, if the entire magnet is covered with a non-magnetic alloy case such as stainless steel as described in the above-mentioned publication for protection, the non-magnetic alloy is interposed between the magnet and the root plate. The power has decreased.

 In view of such a problem, the present inventors, for example, as shown in FIGS. 11 and 12, a pair of yokes 81, 82 made of a corrosion-resistant soft magnetic alloy and erected toward the root plate 80, and A spacer 83 made of a corrosion-resistant non-magnetic alloy provided on the root plate 80 side between the pair of yokes 81, 82, and an S pole and an N pole on the side of the spacer 83 opposite to the root plate And a magnet body 84 provided so as to face both yokes 81, 82, a magnet body 84, a pair of yokes 81, 82, and a spacer 83 except for a base plate side. A dental prosthesis comprising a cap 85 made of a corrosion-resistant non-magnetic alloy covered so as to surround it has been proposed (Japanese Patent Application Laid-Open No. HEI 1-303045, US Patent No. 5,011). 3, 243, etc.).

The dental prosthesis according to this proposal includes a pair of yokes 81, 82 and a base plate made of a soft magnetic alloy, and a magnetic circuit formed therebetween, thereby forming the yokes 81, 82. A large suction force can be generated between the plate and the root plate. Further, since the spacer 83 and the cap 85 do not intervene between the yokes 81 and 82 and the root plate, and are made of a non-magnetic alloy, a strong suction force can be secured. Further, by configuring the size of the denture attachment main body to be within a predetermined range. As a result, the magnetic attraction force per unit volume can be improved, whereby the volume of the denture attachment main body can be reduced, and the size can be reduced.

 However, the denture attachment with the structure proposed above is limited to a height of about 1.5 mm even if the size is reduced to a predetermined range, even if the size is reduced. Becomes For this reason, it cannot be applied unless the mounting space in the height direction is clinically insufficient, and the problem that the applicable range is limited remains.

 The present invention has been made in view of the above problems, and an object of the present invention is to provide a denture attachment that has a large suction force and can be further reduced in size. Disclosure of the invention

 In order to achieve the above object, the present inventors have proposed a conventional denture attachment, in which a pair of yokes erected toward the root plate generate a suction force by contact with a magnet, so that the size reduction is achieved. We focused on the fact that the contact area between the magnet and the yoke was reduced when the attachment was made (when the height of the attachment body was reduced), and decreased almost in proportion to the height. As a result, the inventors have developed a structure in which the contact area between the magnet and the yoke does not become too small even if the size is reduced, and completed the present invention.

That is, the denture attachment of the present invention is a plate-like key made of a soft magnetic alloy implanted on a root plate attached to the top of a tooth root. And an attachment body implanted in the denture base facing the capper and attached to the keeper and attracting by magnetic attraction, wherein the attachment body is At least a pair of yokes disposed on the keeper side and made of a corrosion-resistant soft magnetic alloy; a spacer made of a corrosion-resistant non-magnetic alloy interposed between the pair of yokes; A magnet body disposed so that the keeper side faces the north pole and the anti-keeper side of the other yoke faces the south pole, and forms a pair of magnetic fields vertically with respect to the keeper; Excluding the keeper side, the magnetic body, the pair of yokes, and a cap made of a corrosion-resistant non-magnetic alloy covered so as to integrally surround the spacer. It is a feature.

The magnet body in the present invention may be composed of two magnets arranged in parallel so that the N and S poles face in opposite directions, or the N and S poles may be "" or in the same state. It can be composed of one magnet that has been magnetized twice. In this case, a second yoke is provided on the opposite side of the magnet from the magnet, and the magnet is arranged on the yoke such that the N pole and the S pole on the opposite side of the magnet oppose each other. When composed of two magnets, two flat magnets with N and S poles on both sides are combined, or a ring-shaped magnet with N and S poles on both sides. And a disk-shaped magnet coaxially arranged inside the magnet. Further, the magnet body can be formed of a single U-shaped magnet. As the magnet body, it is preferable to use a rare earth magnet having a maximum energy product of 2 O MGO e (mega-Gauss-Eelsted) or more. Thereby, a denture attachment having a suction force of about 500 gf or more can be obtained. Such rare earth magnets, SmC os, S m- C o based alloys such as Sm ₂ C o _7, and the like Nb- F e- B-based alloy.

 As the soft magnetic alloy of the yoke and the keeper, it is preferable to use a soft magnetic alloy having a saturation magnetic flux density of 1200 G or more and a magnetic permeability of 3000 or more. Soft magnetic alloys having such properties include pure iron, 13 Cr—2Mo steel, 17 Cr—2 Mo steel, and the like. When the saturation magnetic flux density of the soft magnetic alloy is more than 2000 G, the attraction force further increases. Pure iron is one such soft magnetic alloy.

 The attractive force changes by changing the saturation magnetic flux density of the soft magnetic alloy and the maximum energy product of the magnet body. FIG. 9 and FIG. 10 show the relationship. By selecting both characteristics based on both figures, a strong suction force of 500 gf to 100 gf can be obtained.

 Further, it is preferable to apply a surface treatment for protection to the contact surface of the yoke with the capper. Materials for surface treatment include pure iron and permendur.

As the non-magnetic alloy of the spacer and the cap, it is preferable to use a non-magnetic alloy having a magnetic permeability of 1.2 or less. As a non-magnetic alloy having such properties, 17 (: 1 "— 1 21 ^ 1 — 21 ^ 0 鐧 , Titanium alloys and the like.

 Further, in order to enhance the corrosion resistance and the wear resistance, it is preferable that the respective boundary surfaces of the pair of yoke, spacer and cap are joined by welding or brazing. In the case of joining by welding, it is preferable that the penetration depth of the joining surface by welding is 0.02 cascade or more in order to obtain sufficient joining strength.

 The attachment body according to the present invention can be formed in any shape such as a columnar shape, an elliptical columnar shape, a polygonal columnar shape, and a modified columnar shape without departing from the basic internal structure. Further, the keeper can be formed in an arbitrary shape such as a disk shape or a polygonal plate shape corresponding to the outer peripheral shape of the attachment body.

 Next, the operation and effect of the present invention will be described.

 In the denture attachment of the present invention, when the pair of yokes of the attachment body comes into contact with the keeper, a magnetic circuit is formed through the pair of yokes, and a large attractive force is generated between each yoke and the keeper. This magnetic circuit is closed magnetically by a spacer interposed between a pair of yokes, and a cap covered so as to integrally surround the magnet body, the pair of yokes and the spacer, The large suction force is secured.

The magnet body in the denture attachment of the present invention is configured such that the anti-keeper side of one yoke faces the N pole and the anti-keeper side of the other yoke faces the S pole, It is arranged so as to form a magnetic field, so it is possible to shorten the height direction of the instrument body while securing a strong suction force. Becomes

 That is, when the relationship between the height of the attachment main body and the suction force was investigated for the present invention and the conventional denture attachment, the results shown in FIG. 8 were obtained. As shown in Fig. 8, in the conventional case, the suction force decreases almost proportionally as the height of the attachment body decreases, and sharply decreases when the height of the attachment body is less than 1.5 m. This tendency tends to increase. On the other hand, in the case of the present invention, the ratio of the decrease in the suction force to the decrease in the height of the attachment body is smaller than in the conventional case, and a large suction force can be obtained even if the size is reduced.

 Therefore, according to the dental prosthesis of the present invention, a large suction force can be provided and the size can be further reduced as compared with the conventional one, so that the limitation of the clinical application range can be solved. .

 In addition, the denture attachment of the present invention has a structure in which the magnet body is completely sealed by the cap, the pair of yokes and the spacer, and the magnet body does not come into direct contact with the keeper. Wear resistance can be obtained. BRIEF DESCRIPTION OF THE FIGURES

1 Oh an exploded perspective view of a denture § evening Tsuchime emissions Bok according to Example 1 ₀

FIG. 2 is a cross-sectional view of the denture attachment according to the first embodiment. FIG. 3 is a cross-sectional view showing a state in which the denture is attached to the root by the denture attachment according to the first embodiment.

 FIG. 4 is an exploded perspective view of the denture attachment according to the second embodiment.

 FIG. 5 is a plan view of the denture attachment according to the second embodiment as viewed from the attachment body side.

 FIG. 6 is a cross-sectional view of a portion corresponding to line AA in FIG. FIG. 7 is a cross-sectional view of the denture fastener according to the third embodiment. FIG. 8 is a diagram showing the relationship between the main body and the suction force in the present invention and the conventional denture fastener. is there.

 9 and 10 are diagrams showing the relationship between the saturation magnetic flux density of the soft magnetic alloy, the maximum energy content of the magnet body, and the attraction force.

 FIG. 11 is an exploded perspective view of a conventional denture attachment. FIG. 12 is a cross-sectional view of a portion corresponding to line BB of FIG. 11.

BEST MODE FOR CARRYING OUT THE INVENTION

 Hereinafter, embodiments of the present invention will be described with reference to the drawings.

 (Example 1)

As shown in FIGS. 1 and 2, the denture attachment according to the present embodiment includes an octagonal plate-shaped keeper 1 made of a soft magnetic alloy, and an attachment body 2 that is attracted to the keeper 1 by magnetic attraction. ing. The attachment body 2 has a pair of plate-like yokes 21 and 22 arranged on the keeper 1 side. A spacer 23 made of a corrosion-resistant non-magnetic alloy and having the same thickness as the yokes 21 and 22 is interposed between the pair of yokes 21 and 22.

 Two plate-like magnets 24 and 25 are arranged on the opposite side of the pair of yokes 21 and 22 so that the N pole and the S pole face in opposite directions. In one magnet 24, the N pole is in contact with the surface on the anti-keeper side of one yoke 21, and in the other magnet 25, the S pole is in the surface on the anti-keeper side of the other yoke 22. Is in contact with A plate-shaped second yoke 26 is disposed on the anti-keeper side of the two magnets 24 and 25 so as to contact the N pole or the S pole of each of the magnets 24 and 25.

 The second yoke 26, the two magnets 24, 25, the pair of yokes 21, 22, and the spacer 23 are made of non-corrosion-resistant material so as to integrally surround the periphery except the keeper side. A cap 27 made of a magnetic alloy is covered. Then, the boundary surfaces of the workpieces 21 and 22, the spacer 23 and the cap 27 on the side opposite to the keeper 1 should have a penetration depth of at least 0.02 mni by welding. Are joined. The surfaces of the pair of yokes 21 and 22 facing the capper 1 are subjected to a surface treatment for protection using pure iron.

The attachment main body 2 of the present embodiment configured as described above is formed in an octagonal prism having a height of 2.1 mm, and the shape, dimensions, magnetic characteristics and material of each component are described below. Shown in Table 1 <Table 1 (See Figures 1 and 2)

In the denture attachment configured as described above, as shown in FIG. 3, the keeper 1 is planted on the root plate 72 attached to the top of the root 71, and the keeper 1 is opposed to the keeper 1. Attachment body 2 is implanted in denture base 73 and used for use. Then, a pair of yokes 2 1 of the attachment body 2 When the 2 and 2 sides come into contact with the keeper 1, a magnetic circuit is formed through the pair of yokes 21 and 22 and the keeper 1, and about 56 Ogi is provided between each yoke 21 and 22 and the keeper 1. A large suction force is generated, and the denture 73 is firmly held at the root 71.

 As described above, according to the denture attachment of this embodiment, a sufficiently large suction force for holding the denture 73 can be obtained, and the size can be significantly reduced as compared with the conventional one. In addition, both magnets 24 and 25 are completely sealed by cap 27, a pair of yokes 21 and 22 and spacer 23, and both magnets 24 and 25 do not directly contact keeper 1. With the structure, excellent corrosion resistance and wear resistance can be obtained.

 (Example 2)

 As shown in FIGS. 4 to 6, the denture attachment of the present embodiment includes a disk-shaped capper 3 made of a soft magnetic alloy, and an attachment main body 4 which is attracted to the capper 3 by magnetic attraction. It consists of:

The attachment body 4 has a pair of inner and outer yokes 41 and 42 coaxially arranged on the side of the keeper 3. The inner yoke 41 is formed in a disk shape, and the outer yoke 42 disposed coaxially outside the inner yoke 41 is formed in a ring plate shape. A spacer 43 made of a corrosion-resistant non-magnetic alloy is interposed between the inner and outer yokes 41 and 42. The spacer 43 is formed in the shape of a ring plate with the same thickness as the inner and outer yokes 41, 42, and the inner and outer peripheral surfaces thereof are in contact with the inner and outer yokes 41, 42. Are located.

 On the anti-keeper side of the inner and outer yokes 41, 42, a disc-shaped magnet 44 and a ring-shaped magnet 45 fitted coaxially so that the N and S poles face in opposite directions. Are located. The disk-shaped magnet 44 has an N pole in contact with the surface on the opposite side of the keeper of the inner yoke 41, and the ring-shaped plate magnet 45 has an S pole having an S-pole opposite to the outer keeper 42. In contact with the surface. A plate-shaped second yoke 46 is disposed on the anti-kipper side of the two magnets 44, 45 so as to contact the N pole or the S pole of each magnet 44, 45. .

 The second yoke 46, the magnets 44, 45, the inner and outer yokes 41, 42, and the spacer 43 are provided with a cap 4 made of a corrosion-resistant nonmagnetic alloy and having a bottomed cylindrical shape. 7 are crowned. The boundary between the inner and outer yokes 41, 42, the spacer 43, and the cap 47 on the side facing the capper 3 has a penetration depth of 0.02 mm by welding. It is joined so that it becomes above. The surfaces of the inner and outer yokes 41, 42 facing the capper 3 are surface-treated with pure iron for protection.

The attachment body 4 of the present embodiment configured as described above is formed in a columnar shape having a height of 2.1 mm, and the shape, dimensions, magnetic characteristics and materials of each component are shown in Table 2. Shown in Table 2 (See Figures 4 to 6)

以下余白 以上のように構成された本実施例の義歯アタッチメントは

Below margin The denture attachment of the present embodiment configured as described above is

However, it is utilized similarly to the case of the first embodiment, and a large attractive force of about 59 Ogf is generated between the inner and outer yokes 41, 42 and the capper 3 by forming a magnetic circuit. Can be done.

 Therefore, also in the case of the denture attachment of the present embodiment, a large suction force can be obtained, and the same effect as that of the first embodiment can be obtained.

 (Example 3)

 As shown in FIG. 7, the denture attachment according to the present embodiment includes a plate-like keeper 5 made of a soft magnetic alloy, and an attachment main body 6 that is attracted to the keeper 5 by magnetic attraction.

O

 The attachment body 6 has a pair of plate-like yokes 61 and 62 disposed on the keeper 5 side. A spacer 63 made of a corrosion-resistant nonmagnetic alloy and having the same thickness as the yokes 61 and 62 is interposed between the pair of yokes 61 and 62.

A pair of magnets 64 curved in a U-shape are arranged on the opposite sides of the pair of yokes 61 and 62. The magnet 64 has an N pole formed at one end in contact with the surface of one yoke 61 on the opposite side of the keeper, and an S pole formed at the other end has a counterpart of the other yoke 62. It is arranged so as to contact the side surface. The magnet 64, the pair of yokes 61, 62, and the spacer 63 are provided with a dome-shaped cap made of a corrosion-resistant non-magnetic alloy. Step 67 is covered. Each boundary surface of the pair of yokes 61, 62, spacer 63, and cap 67 on the side facing the keeper 5 is joined by welding so that the penetration depth becomes 0.02 mm or more. Have been. The surfaces of the inner and outer yokes 61 and 62 facing the caper 5 are subjected to a surface treatment for protection with pure iron.

 The attachment main body 6 of the present embodiment configured as described above is formed in a columnar shape with a height of 1.9 sq. Mm. Shown in

Table 3 (See Figure 7)

Shape (mm) Magnetic properties Material Rare earth magnet Width 1 Width 2 Height Maximum energy product Nd ₂ Pe ₁₄ Bi Febble stone 64) 3.0 3.0 1.6 30MGOe Soft magnetic alloy Width 1 Width 2 Height Saturated magnetic flux density Permeability 13Cr-2 o

 (Yoke 61.62) 3.0 1.3 0.2 17000G 5000 Stainless steel non-magnetic alloy Width 1 Width 2 Height Magnetic permeability 17Cr-12Ni-2 o (-The 63) 3.0 0.4 0.2 1.02 Stainless steel Non-magnetic alloy Thick magnetic permeability 17Cr-12Ni -2Mo (Carip 67) 0.1 1.02 Stainless steel Soft magnetic alloy Width 1 Width 2 Height Saturated magnetic flux density Permeability 13Cr-2 o

(Keeper 5) 3.2 3.2 '1.0 17000G 5000 Stainless steel The denture attachment of the present embodiment configured as described above is

It is used in the same manner as in the first embodiment, and a large suction force of about 52 Ogf is generated between the yokes 61, 62 and the capper 5 by forming a magnetic circuit. be able to.

 Therefore, also in the case of the denture attachment of the present embodiment, a large suction force can be obtained, and the same effect as that of the first embodiment can be obtained.

 Further, in the case of the present embodiment, the magnet body is constituted by one U-shaped magnet 64, so that the second yoke used in the above embodiment is not required, so that the number of parts is reduced. And the structure can be simplified.

Claims

The scope of the claims (1) A plate-shaped keeper made of a soft magnetic alloy and implanted on a root plate attached to the top of a tooth root, and a keeper implanted on a denture base facing the keeper and magnetically coupled with the keeper. A denture attachment comprising an attachment body that is attracted by a suction force, wherein the attachment body comprises at least a pair of yokes made of a corrosion-resistant soft magnetic alloy arranged on a keeper side, and the pair of yokes. ■ A spacer made of a corrosion-resistant non-magnetic alloy interposed between the two yokes, the anti-keeper side of the one yoke faces the N pole, and the anti-keeper side of the other yoke faces the S pole. A magnet body disposed so as to form a pair of magnetic fields in a vertical direction with respect to the coiler; and the magnet body, the pair of jokes and the spacer, except for a keeper side. A cover made of a corrosion-resistant non-magnetic alloy covered so as to surround it Denture attachment to Toku徵 that it is composed of a flop.  (2) The magnet body is composed of two plate-like magnets in which the N pole and the S pole face in opposite directions and are arranged in parallel, and the N pole and the S pole on the anti-keeper side of the two magnets are both 2. The denture attachment according to claim 1, wherein the attachment is arranged so as to face a second yoke provided on a side opposite to the keeper of the magnet. (3) The denture attachment according to claim 1, wherein the magnet body is constituted by one U-shaped magnet. (4) The denture attachment according to claim 1, wherein the magnet body is a rare earth magnet having a maximum energy product of 2 OMGOe or more.  (5) The corrosion-resistant soft magnetic alloy of the yoke has a saturation magnetic flux density of at least 1200 G and a magnetic permeability of at least 300, and the corrosion-resistant non-magnetic alloy of the spacer and the cap has a magnetic permeability of 2. The denture attachment according to claim 1, wherein the ratio is not more than 1.2.  (6) The corrosion-resistant soft magnetic alloy of the yoke has a saturation magnetic flux density of 2000 G or more, and the contact surface of the yoke with the chipper is subjected to a heat-proof surface treatment. A denture attachment according to claim 1.  (7) The denture attachment according to claim 1, wherein a boundary surface between the yoke, the spacer and the cap is joined by welding or brazing.  (8) The welding depth of the joint surface is 0.02 mm or more, and the spacer height is 0.05 to 1.0 mm. Denture attachment.