JPH06225890A - Magnetic crown prosthetic material - Google Patents

Abstract

PURPOSE:To provide a crown prosthetic material hardly removed with a porcelain-baked front crown from a support base tooth even when the coupling adhesive strength is weakened. CONSTITUTION:A support base tooth 3 is constructed on a detal pulp-removed root 1, a crown 5 is fitted here to form a crown prosthetic material for prosthesis, the whole or part of the support base tooth 3 is made of a stainless steel alloy 7, a magnet assembly 8 is fixed in the crown 5, the magnetic stainless steel alloy 7 and the magnet assembly 8 are closely stuck when the crown 5 is fitted to the support base tooth 3, and the mutual magnetic attraction serves the role to fix the crown 5 to the support base tooth 3 in the magnetic crown prosthetic material.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic attachment applied to a coronary prosthesis.

[0002]

2. Description of the Related Art As shown in FIG. 2, for example, a coronary prosthesis in which one anterior tooth of the upper jaw is removed is conventionally a pulp prosthesis of the tooth, and the root 1 is an abutment in the root. The abutment tooth 3 is built by casting so as to fit in the tooth hole 2, the abutment tooth 3 is cemented to the abutment tooth hole 2, and the porcelain material 4 is cast on the abutment tooth 3. It is produced by fitting and adhering the porcelain veneer crown 6 (shown in FIG. 3), which has been baked onto.

[0003]

In the crown prosthesis thus produced, the porcelain baking front crown 6 may be dislocated from the abutment tooth 3 due to the action of the occlusal force for a long period of time. For the purpose of the present invention, even when the fitting adhesive strength is weakened in this way, the porcelain baking front crown 6 is fixed to the abutment tooth 3.
It is to provide a crown prosthesis that is harder to slip off.

[0004]

In order to achieve the above-mentioned object, in a crown prosthesis in which an abutment tooth is constructed on a tooth root from which pulp is removed, and a crown is attached to the abutment tooth for prosthesis, all or one of the abutment teeth is provided. The part is made of magnetic stainless alloy, the magnet assembly is fixed inside the crown, and when the crown is attached to the abutment tooth, the magnetic stainless alloy and the magnet assembly are closely attached to each other. The magnetic attraction force is also characterized in that it plays a role of fixing the crown to the abutment tooth. The magnet assembly includes a permanent magnet, a case made of a corrosion-resistant magnetic material having a recess for accommodating the permanent magnet, and a seal plate made of a corrosion-resistant material for covering the permanent magnet so as not to be exposed from an opening of the case recess. The seal plate is composed of two types of components, a seal edge member made of a corrosion-resistant non-magnetic material and a seal plate made of a corrosion-resistant soft magnetic material having an outer peripheral shape substantially the same as the inner peripheral shape of the seal edge member. And the abutting portion of the case and the seal plate are seam welded. Further, the permanent magnet used in the present invention is required to be small in size and to obtain a magnetic flux as strong as possible. Therefore, SmCo
A rare earth magnet such as a system magnet or a NdFe system magnet is used. Further, the shape thereof is usually cylindrical or cylindrical although it depends on the portion to be used.
Therefore, the ring-shaped thin plate member as the seal edge member,
A disk-shaped thin plate member is often used as the seal plate. The permanent magnet is usually magnetized before it is put into the case, but it may be magnetized after the magnet body is assembled.

[0005]

1 is a sectional view of a magnetic coronary prosthesis showing an example of the present invention. The pulp of the tooth root 1 is taken and an abutment tooth hole 2 is formed. Take an impression as usual, make a model with stones, and wax up on the model. After waxing up to a predetermined height, Fe 68 wt% -Cr 30 wt% -Mo 2 wt with a diameter of 3.5 mm and a thickness of 2 mm
A magnetic stainless alloy whose main component is% is embedded in the wax so that the vertex is left and the three sides are surrounded by the wax. After this, it is buried in the investment material as usual, the wax is run, and the gold-palladium alloy is cast by the casting machine,
The abutment tooth 3 is produced. The abutment tooth 3 was fitted on the model, and the diameter was 3.5 mm and the thickness was 4 on the magnetic stainless alloy.
A magnet assembly of mm is placed, and in this state a wax crown is formed, then a wax pattern is taken, and a cast crown S is made of a gold alloy as usual. The cast crown 5 and the porcelain 4 are baked, and the magnet assembly 8 is bonded with an adhesive. When this is fitted to the abutment tooth, in addition to the fitting frictional force between the abutment tooth 3 and the casting crown 5, the magnetic attraction force of the magnetic alloy 7 and the magnet assembly 8 also acts, so The porcelain front crown was not detached from the abutment tooth. Further, FIG. 4 shows a sectional view of the magnet structure of the present invention. In FIG. 4, 11 is a permanent magnet, 12 is a case made of corrosion-resistant stainless steel having magnetism, 15 is a seal edge member and a sealing disk made of non-magnetic corrosion-resistant stainless steel, and 14 is an adhesive. As shown in the figure, the outer peripheral portion of the case 12 and the abutting portion 20 of the seal ring 15, or the seal ring 15 and the seal disc 16 are attached.
Since the butt portion 30 of (1) is sealed by laser welding, the problem of corrosiveness of the rare earth magnet could be solved.

[0006]

According to the present invention, it has been conventionally insufficient.
The reduction of the mating adhesive force of the coronary prosthesis over a long period of time can be prevented by the addition of the magnetic attraction force.

[Brief description of drawings]

FIG. 1 is a sectional view of a magnetic crown prosthesis showing an embodiment of the present invention.

FIG. 2 is a sectional view showing a conventional coronary prosthesis.

FIG. 3 is a diagram showing a structure of a porcelain front cover.

FIG. 4 is a cross-sectional view of a magnet structure showing an example of the present invention.

[Explanation of symbols] 1 tooth root 3 abutment tooth 4 porcelain 5 cast crown 7 magnetic alloy 8 magnet assembly

Claims (2)

[Claims] 1. A crown prosthesis in which an abutment tooth is built on a pulp-rooted root and a crown is attached thereto for prosthesis, wherein all or part of the abutment tooth is constructed of a magnetic stainless alloy. , The magnet assembly is fixed inside the crown, the magnet assembly is fixed inside the crown, and when the crown is attached to the abutment tooth, the magnetic stainless alloy and the magnet assembly are in close contact with each other. A magnetic crown prosthesis characterized in that their mutual magnetic attraction also serves to fix the crown to the abutment tooth. 2. The magnet structure comprises a permanent magnet, a case made of a corrosion-resistant magnetic material having a recess for accommodating the permanent magnet, and a non-corrosion-resistant non-corrosion cover for covering the permanent magnet from the opening of the case recess. A seal plate made of a magnetic material, the seal plate being a seal edge member made of a corrosion-resistant non-magnetic material and a seal plate made of a corrosion-resistant soft magnetic material having an outer peripheral shape substantially the same as the inner peripheral shape of the seal edge member. The magnetic crown prosthesis according to claim 1, wherein the case and the seal plate are seam welded at the butting portion.