JP4285681B2 - Denture magnetic attachment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a magnetic attachment for a denture that uses a magnetic attractive force of a permanent magnet for fixing a denture in the field of dentistry.
[Prior art]
[0002]
Conventionally, for a prosthesis of a single-sided free end defect, it is a principle to design a double-sided denture that is balanced on the opposite side of the defect. In particular, when there is an intermediate tooth defect or a free end defect on the opposite side, a denture with a high degree of stability is designed in principle by connecting both.
However, since a connecting bar or the like is added, the denture becomes larger for the size of the defect and is generally not accepted by the patient. In addition, it is difficult to adopt a prosthetic design based on such a connection in the case of a few missing teeth. Therefore, if the shape of the alveolar cavity is good, can withstand the occlusal pressure and the lateral pressure, and the health condition of the maintenance teeth is also good, a denture with a one-side treatment may be designed.
[0003]
Conventionally, as a maintenance device for fixing these unilateral dentures to a maintenance tooth, there are an intracoronary attachment to an overdenture maintenance tooth, a cone telescope, etc. in addition to a clasp (see Non-Patent Document 1).
In addition, there is an extracoronal attachment called a so-called Dalbo attachment (see Non-Patent Document 2 and Patent Document 1).
In addition, a magnetic attachment using a magnetic attraction force is also known (see Patent Document 2), although it is not normally used for a free end defect prosthesis. And there exists improvement of a keeper at the time of using a magnetic attachment as an attachment outside a crown (refer patent document 3).
[0004]
[Non-Patent Document 1]
"Quintessence of Dental Technology Vol.16 December 1991"
[Non-Patent Document 2]
"Dental Technician: Separate Attachment Dental Technician September 1981"
[Patent Document 1]
JP 2001-170081 [Patent Document 2]
Japanese Patent No. 2795755 [Patent Document 3]
JP-A-2001-299781
[Problems to be solved by the invention]
About the above prior art, since a metal part touches an external appearance, a clasp is unacceptable from an aesthetic problem. Moreover, since a maintenance tooth is shaken by a side force acting, it may cause a worse prognosis.
In addition, since the structure of the Cornus telescope and the endodontic attachment is complicated, in a case where the intermaxillary distance is small, it is necessary to largely excise the crown portion in order to secure the space of the device. Also, the more precise and firm the maintenance, the more the maintenance teeth are shaken by the lever stress, and the burden on the maintenance teeth is not necessarily reduced compared to the clasp.
Further, even if the extra-coronal attachment is considered to be removable by the operator and the patient, the attachment / detachment by the patient is not always easy. In addition, there is an example in which the spring and the hinge are broken, which easily causes denture swaying and mastication problems, and it is necessary to perform complicated management such as adjustment of the spring and rebase processing by repeating recall in a short period of time. Further, these extra-coronal attachments have a clear single rotation axis, and when used on both sides, it is difficult to match the left and right rotation axes, and it is difficult to use them together with a connecting bar.
[0006]
On the other hand, as shown in FIG. 7, the magnetic attachment using magnetic attractive force is basically composed of a magnet structure 1 in which a permanent magnet is housed in a magnetic yoke 9 made of a soft magnetic material and a keeper 2 made of a soft magnetic material. It is configured. The magnet structure 1 is fixed with a dental adhesive in a mounting hole of a denture base 6 in which artificial teeth 5 are implanted. The keeper 2 is attached to a root surface plate 3 in which a dental alloy such as a gold-silver-palladium alloy or the like is coated on the upper portion of the tooth root 4 by casting. This magnet structure 1 is disposed opposite to a keeper 2 made of magnetic stainless steel, and a magnetic flux generated from a permanent magnet is guided to the keeper side by a yoke, and a magnetic attractive force Fm generated between the magnet structure 1 and the keeper 2 is used. By doing this, the denture is fixed.
[0007]
This magnetic attachment is used to maintain the space between the denture base 6 and the tooth root 4 and uses only the vertical magnetic attraction force acting between the magnet structure and the keeper. The feature is to escape. However, in the case of a single-side free-end denture, a vertical maintenance force alone is not sufficient, and a horizontal induction force that slides and comes into close contact with the maintenance tooth when the denture is mounted is also necessary. For these reasons, the conventional magnetic attachment has not been sufficiently effective for maintaining the free end on one side.
[0008]
Therefore, an object of the present invention is to provide an attachment for a denture that can stably fix the denture, reduce the burden on the maintenance tooth, and improve the usability as the above-described one-side free-end denture maintenance device.
[0009]
[Means for Solving the Problems]
The present inventors have, as means for solving the above problems, the combination of the magnet structure and keeper exerting a retentive force with respect to the two directions of the horizontal and vertical directions, the use of this support system of one free end Thought.
That is, the present invention is composed of a keeper provided on the magnet structure and maintaining teeth provided on the denture and without to secure the dentures and maintaining teeth by magnetic attractive force acting between the magnet structure and keeper dentures The keeper is substantially L-shaped having a vertical attracting surface and a horizontal attracting surface, and the magnet structure is sandwiched between a pair of yokes made of a soft magnetic material and the yoke. A permanent magnet magnetized in a direction from one yoke to the other yoke, and a shield case made of a non-magnetic material sandwiched between the pair of yokes and in contact with a non-magnetized surface of the permanent magnet. a denture magnetic attachment, characterized in that that form a magnetic circuit for generating a magnetic attraction force toward the horizontal suction surface and the magnetic attraction force toward the suction surface.
[0012]
Further, the present invention comprises a denture having a magnet structure provided on a denture and a keeper provided on a maintenance tooth, wherein the denture and the maintenance tooth are fixed by a magnetic attractive force acting between the magnet structure and the keeper. The keeper is substantially L-shaped having a vertical attracting surface and a horizontal attracting surface, and the magnet structure is a first magnet structure magnetically attracted to the vertical attracting surface. , as well as have a second magnet structure that is magnetically attracted to the horizontal suction surface, each said magnet structure includes a cup yoke made of a soft magnetic material, a permanent magnet held in said yoke, said cup provided in an opening portion of the yoke, Ru can configure and to Rukoto having a sealing plate made of a soft magnetic material and a seal plate made of a non-magnetic ring provided on its outer periphery.
In the present invention, the magnet structure may Rukoto attached to partial denture (partial denture).
[0013]
DETAILED DESCRIPTION OF THE INVENTION
One of the features of the magnetic attachment for dentures of the present invention is that a magnetic circuit for generating a horizontal magnetic attractive force and a vertical magnetic attractive force is provided at the same time. As a result, it is in charge of the maintenance force perpendicular to the occlusal surface, positioning at the time of wearing, and prevention of the movement of the near-distal denture. Therefore, it is possible to obtain stable maintenance of the denture and to prevent an excessive lateral force from being applied to the maintenance tooth. Further, the keeper is substantially L-shaped and is characterized in that a high magnetic attractive force can be maintained without leakage of the magnetic flux by the horizontal magnetic circuit and the vertical magnetic circuit. As the magnetic circuit, a sandwich type in which a permanent magnet is sandwiched between yokes, a pole piece type through a pole piece, and the like are conceivable.
[0014]
Hereinafter, the Example of the magnetic attachment for dentures of this invention is described.
FIG. 1 shows an example of an extracoronal magnetic attachment according to the present invention. A magnet structure 21 is attached to the denture base 6 of the one-side free-end denture with an adhesive or the like, and a keeper 17 made of a soft magnetic material having a substantially L-shape is fixed to the crown 16 of the maintenance tooth 15 with an adhesive or the like. The denture base 6 is maintained by a magnetic attractive force generated between the structure 21 and the keeper 17. The magnetic attraction force forms a magnetic circuit that generates a magnetic field in each of the vertical direction FmV (apical direction) and the horizontal direction FmH (the front-rear direction of the denture in the near-centrifugal direction) on the occlusal surface, and the horizontal surface 20 on the keeper 17 side. Magnetic paths through which the magnetic flux passes are formed between the vertical surface 19 and the magnetic attractive force is generated and maintained. This prevents the denture from lifting when chewing the sticky food, and also allows the patient to easily attach and detach the denture while wearing the denture while maintaining the risk of accidental ingestion of the denture. Can be reduced.
[0015]
As shown in FIGS. 1 and 2, the substantially L-shaped keeper is fixed with a dental adhesive in a keeper space provided outside the maintenance tooth crown. The L-shaped keeper 17 is made of soft magnetic stainless steel such as SUS447J1 or SUSXM27 and is formed in a substantially L-shape. The substantially L-shaped configuration does not necessarily mean that the opening angle is 90 degrees. For example, in order to have the horizontal magnetic attraction force FmH to the minimum necessary, it should be 120 degrees or less with respect to the horizontal plane. This is because it is desirable and 90 degrees or more is desirable in order to easily come off when necessary. Further, the L shape does not need to be integrally processed from one flat plate, and may be configured by combining two or a plurality of flat plates. At this time, a concave groove for making it difficult to come out from the crown can be provided, or a surface can be roughened to improve adhesion.
[0016]
An example of a magnet structure incorporating a magnetic circuit that generates a magnetic attractive force in the horizontal and vertical directions is shown in FIG. FIG. 2 shows a front view, a side view, and a top view. In this magnet structure 21, a permanent magnet 11 having a magnetic pole positioned so as to face the yoke is sandwiched between side yokes 22 made of soft magnetic stainless steel such as SUS447J1 or SUSXM27, and the upper and lower sides thereof are made of nonmagnetic stainless steel such as SUS316. Both are sealed by seal welding such as laser welding or electron beam welding through a shield case 23.
The permanent magnet 11 is simply magnetized in such a way that the S pole is provided on one side and the N pole is provided on the other side, the SN pole is arranged in parallel on one side, and the NS pole is arranged in parallel on the other side. Various configurations can be made. In any case, the magnetic flux 14a emitted from one side is guided to the side yoke 22, passes through the horizontal attracting surface 20 of the substantially L-shaped keeper 17 while avoiding the shield case 23, and returns to the permanent magnet 11 through the other side yoke 22 again. A closed magnetic path a is formed, thereby generating a magnetic attracting force FmV in the vertical direction to obtain a maintaining force. On the other hand, the magnetic flux 14 b emitted from the permanent magnet 11 is guided to the side yoke 22, passes through the vertical attracting surface 19 of the substantially L-shaped keeper 17 while avoiding the shield case 23, and again passes through the other side yoke 22 to pass through the permanent magnet 11. A closed magnetic path b is formed so as to return to the horizontal direction, whereby a horizontal magnetic attractive force FmH is generated to obtain a maintaining force. Thus, a magnetic circuit for generating a horizontal magnetic attractive force and a vertical magnetic attractive force is provided at the same time.
[0017]
An example of another magnet structure is shown in FIG. The magnet structure 21 has a permanent magnet 11 oriented through a pole piece 24 made of a soft magnetic material with the magnetic poles N and S oriented in a direction facing the vertical attracting surface 19 of the substantially L-shaped keeper 17 and attached to the magnetic pole. A closed magnetic path c that returns from the vertical attracting surface 19 of the substantially L-shaped keeper to the pole piece through the horizontal attracting surface 20 is formed, thereby generating and maintaining the horizontal magnetic attractive force FmH and the vertical magnetic attractive force FmV. Gaining power. Thus, a magnetic circuit for generating a horizontal magnetic attractive force and a vertical magnetic attractive force is provided at the same time. In this case, the permanent magnet 11 may be magnetized by left and right two-pole magnetization as shown in FIG. 3 , but it may be one-sided two-pole magnetization or multipole near the attracting face direction as shown in FIG. 4B . It is.
[0018]
Since the magnetic attachment is required to be small, it is desirable that the vertical magnetic attractive force FmV and the horizontal magnetic attractive force FmH be generated simultaneously by a single biaxial magnet structure as in the above example. However, depending on the position of the one-side free end denture, the retention force, and the case, it may be desired to increase or decrease the vertical magnetic attractive force FmV and the horizontal magnetic attractive force FmH. For example, there is a case where the side force attracted to the maintenance teeth is weakened and it is desired to easily separate. In such a case, the vertical magnet structure and the horizontal magnet structure can be formed as separate single-axis magnet structures, and a magnet structure having a low horizontal magnetic attractive force can be used.
[0019]
According to another embodiment of the magnetic attachment of the present invention, a first magnet structure having a magnetic circuit for generating a horizontal magnetic attraction force, and generating a magnetic attraction force in a vertical direction or an angle with the horizontal direction. The second magnet structure having the magnetic circuit is arranged in the vertical direction and the horizontal direction, respectively. That is, as shown in FIG. 6, a magnet structure (single-axis magnet structure) that generates a magnetic attractive force in a uniaxial direction is arranged so that the central axes are substantially orthogonal.
The first and second magnet structures shown in FIG. 5 can be used. This single-axis magnet structure 14 includes a cup-shaped yoke 10 made of a soft magnetic material having a recess, a permanent magnet 11 accommodated in the recess, and an opening of the cup yoke 10 so that the permanent magnet 11 is recessed. The seal plate includes a seal plate 12 made of a soft magnetic material and a nonmagnetic ring 13 made of a nonmagnetic material on the outer periphery thereof. The cup yoke 10, the nonmagnetic ring 13, and the seal The adjacent portion of the plate 12 is integrally welded W. Cup-type magnet structures of the same size or different sizes are arranged so that the axes intersect in the vertical direction and the horizontal direction, and are arranged opposite to the above-described substantially L-shaped keeper 17 so as to close the magnets as shown in the respective magnet structures. A magnetic attraction force is generated by the road loop d to obtain a maintenance force.
[0020]
Further, as another embodiment of the first and second magnet structures, a pair of flat yokes made of a soft magnetic material, a permanent magnet having magnetic poles arranged in the direction of the pair of flat yokes, There is a sandwich type composed of a spacer made of a nonmagnetic material provided between a pair of yokes below a permanent magnet, and a case made of a nonmagnetic material covering the yoke, the permanent magnet and the spacer. Further, instead of the case, an annular cap that covers only the spacer portion may be formed, and the yoke and the cap may be joined by seal welding.
[0021]
As described above, in the conventional non-movable mechanical root surface attachment, clasp method, and Cornus telescope method, a load (side force) in the direction of tilting the maintenance teeth is added as the denture moves in parallel. According to the magnetic attachment of the present invention, an appropriate maintenance force works in the vertical direction (apical direction: physiological displacement direction) and the horizontal direction, and when excessive inclination occurs, the adsorption is disengaged, so a rational and preferable load situation It becomes.
In addition, in the attachment outside the crown, such as a mechanical movable attachment that employs a hinge type as a conventional movable mechanism, it is necessary to set the rotation axis accurately, especially when using multiple devices. It was difficult to take out the prosthetic design and the technical operation. In that respect, according to the magnetic attachment of the present invention, since magnetic attraction force is used, such preparation is unnecessary and handling becomes extremely easy. The magnetic attractive force at this time can also be easily changed by selecting a magnet structure design or a ready-made product. Furthermore, it is easy to attach and detach by the patient of the denture, which is advantageous from the viewpoint of cleanability and hygiene, and is easily removed when an abnormal force exceeding the suction force is applied to the denture, making it difficult to damage the root of the tooth. After the excessive weight is removed, it is naturally adsorbed at a fixed position, so it is easy to use.
[0022]
【The invention's effect】
As described above, according to the present invention, as a device for maintaining a one-side free-end denture, a denture magnetic attachment that reduces the burden on the maintenance teeth and improves the usability can be provided.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram showing a magnetic attachment of a magnet structure and a keeper according to an embodiment of the present invention.
FIG. 2 is a front view, a side sectional view, and a top sectional view showing an embodiment of a magnet structure of the present invention.
FIGS. 3A and 3B are a front view and a top sectional view showing another embodiment of the magnet structure of the present invention. FIGS.
4 is a cross-sectional view illustrating another magnetized form of the magnet structure of FIG. 3;
FIG. 5 is a cross-sectional view of a cup-type magnet structure according to still another embodiment of the present invention.
6 is a side cross-sectional view showing a magnetic attachment of the present invention when the magnet structure of FIG. 5 is used. FIG.
FIG. 7 is a schematic configuration diagram illustrating a conventional magnetic attachment.
[Explanation of symbols]
1: Magnet structure, 2: Keeper, 3: Root face plate, 4: Tooth root, 5: Artificial tooth, 6: Denture base, 7: Root canal, 8: Gingiva, 9: Magnetic yoke, 10: Cup type yoke, 11 : Permanent magnet, 12: Seal plate, 13: Non-magnetic ring, 14: Single axis magnet structure, 15: Maintenance teeth, 16: Crown, 17: Almost L-shaped keeper, 18: Alveolar bone, 19: Vertical adsorption Surface: 20: horizontal attracting surface, 21: biaxial magnet structure, 22: side yoke, 23: shield case, 24: pole piece,

Claims (2)

A magnetic attachment for a denture comprising a magnet structure provided on a denture and a keeper provided on a maintenance tooth, wherein the denture and the maintenance tooth are fixed by a magnetic attractive force acting between the magnet structure and the keeper. The keeper is substantially L-shaped having a vertical attracting surface and a horizontal attracting surface, and the magnet structure is composed of a pair of yokes made of a soft magnetic material, and one yoke from the other to the other Magnetic attraction toward the vertical attracting surface, comprising: a permanent magnet magnetized in a direction toward the yoke; and a shield case made of a nonmagnetic material sandwiched between the pair of yokes and in contact with the non-magnetized surface of the permanent magnet denture magnetic attachment which is characterized that you form a magnetic circuit for generating magnetic attraction force and toward the said horizontal suction surface. A magnetic attachment for a denture comprising a magnet structure provided on a denture and a keeper provided on a maintenance tooth , wherein the denture and the maintenance tooth are fixed by a magnetic attractive force acting between the magnet structure and the keeper. The keeper has a substantially L shape having a vertical attracting surface and a horizontal attracting surface, and the magnet structure includes a first magnet structure magnetically attracted to the vertical attracting surface and the horizontal attracting surface. Each of the magnet structures is provided at a cup yoke made of a soft magnetic material, a permanent magnet held in the yoke, and an opening of the cup yoke. A magnetic attachment for dentures, comprising a seal plate made of a soft magnetic material and a seal plate made of a non-magnetic ring provided on the outer periphery thereof .

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