JPS6137346B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a dental magnetic alloy containing gold, palladium, and cobalt as main components, and in particular to a dental magnetic alloy suitable for performing dental prosthetics and orthodontics in combination with Hikyu magnets having high magnetic energy such as rare earth cobalt magnets. It relates to soft magnetic alloys. The use of Hikyu magnets in denture prostheses is known, for example, in US Pat. No. 2709301, US Pat.
It is well known from the various specifications of the No. However, conventionally, alnico magnets and ferrite magnets have been used as permanent magnets, which has the disadvantage that the volume of the magnet must be large in order to obtain the necessary attractive or repulsive force, which limits the range of use. ,
There are also examples of using platinum-cobalt magnets, but the use of permanent magnets in dental prosthetics has not been widely put into practical use due to reasons such as the fact that these magnets are too expensive and are not always satisfactory. . However, in recent years, rare earth cobalt-based magnets with extremely excellent magnetic properties have been developed and put into practical use, making it easy to obtain extremely strong magnetic attraction with small magnets. It is being reviewed again. In addition, it is predicted that the scope of application will be extremely wide by not only using rare earth cobalt magnets alone but also by combining these magnets with dental soft magnetic alloys. It is hoped that a soft magnetic alloy for use will emerge. For example, as shown in FIG. 1, a soft magnetic alloy 3 is embedded in the tooth root 2 remaining in the gingival region 1, and a rare earth cobalt based magnet 5 is placed inside the tooth crown 4, one of the magnetic poles of which is made of the soft magnetic alloy. Set up so as to face 3,
A possible method is to fix the two using magnetic attraction. This method has the advantage that the range of use is not limited because the degree of freedom in embedding the magnetic alloy in the tooth root is greater than the conventionally known method that utilizes the magnetic attraction force that acts between a pair of Hikyu magnets. be. The saturation magnetic flux density required for magnetic alloys used in combination with rare earth cobalt magnets, for example in dental prosthetics or orthodontics, etc., is suitable for complete dentures, partial denture bases, bridges, crowns, and filling materials. The final decision will be made clinically depending on the method and location used, the size and shape of the rare earth cobalt magnet, the distance between the magnet and the magnetic alloy, the required attraction force, etc., but in general There is an appropriate range for . For example, in order to achieve the configuration shown in Figure 1, the saturation magnetic flux density of the magnetic alloy must be at least 2000G or higher, preferably 4000G or higher, but on the other hand, it is difficult to maintain multiple dentures simultaneously. Therefore, even a smaller value is practical. The present invention has been made in response to the above requirements, and an object of the present invention is to provide a dental magnetic alloy having characteristics optimal for use in combination with rare earth cobalt magnets. In order to achieve the above object, the present invention is an alloy characterized by containing cobalt, palladium and gold as main components. The present applicant has proposed an alloy containing cobalt and palladium as its main components (patent application filed in 1973-
126145), alloys containing nickel and palladium as main components (Patent Application No. 135106, 1982), cobalt,
An alloy containing nickel and palladium as main components (Japanese Patent Application No. 12206/1983) was previously proposed, and the present invention has properties equivalent to these alloys. In the present invention, cobalt is a basic element for obtaining soft magnetic properties, and is 15% by weight (the same applies hereinafter).
It is practical if the cobalt content is ~70%, but in order to make the saturation magnetic flux density 4000G or more, it is necessary to contain cobalt by 20% or more. In the present invention, palladium is effective for increasing the hardness of the alloy without deteriorating its corrosion resistance, and in practical terms, it is necessary to contain at least 5% or more, preferably 10% or more. On the other hand, if the palladium content exceeds 70%, the melting point of the alloy will be high and casting will be difficult.
Must be less than or equal to In the present invention, gold is contained in order to improve corrosion resistance, but it is necessary for the total content of gold and palladium to be at least 30% for practical purposes, and desirably 35% or more. On the other hand, the content including gold and palladium is 85%
If the saturation magnetic flux density exceeds 4000G, the saturation magnetic flux density becomes extremely small and causes practical problems, so it is necessary to keep the saturation magnetic flux density below 85%.
Must be below 80%. In addition, in the present invention, Mn, Zn, Sn,
One or more of Al, Si, and Mg may be added, but the content of these is 5%.
If the content exceeds 5%, the alloy becomes brittle, so the content must be 5% or less. Hereinafter, the present invention will be explained in detail with reference to Examples. Alloys of various compositions were melted in an argon arc melting furnace, cast into predetermined shapes, and the magnetic properties and corrosion resistance of the resulting cast bodies were measured, and the results shown in Table 1 were obtained.

[Table] In the table, corrosion resistance was measured using 0.1% Na ₂ S as a corrosive liquid under the conditions specified in JIS. If no discoloration was observed, it was indicated by ○, and if discoloration was observed, it was indicated by ×. There is. As is clear from the table, in the present invention, as the Co content increases, the saturation magnetic flux density increases, but when the Co content exceeds 70% and the content including gold and palladium decreases, corrosion resistance deteriorates. Become. On the other hand, when the Co content is less than 15, the saturation magnetic flux density is 2000G.
It has fallen below. Therefore, the Co content is 20~
70% is desirable. In addition, Mn, Zn, Sn, Al, Si,
Even if Mg was contained in an amount of 5% or less, the magnetic properties and corrosion resistance were hardly affected, and the castability was improved. In addition, Pt and Cr are added to increase hardness without deteriorating corrosion resistance, and Ag to lower melting point.
and Cu, and Fe and Cu to increase the magnetic flux density.
Adding Ni was effective. As detailed above, the present invention is a dental magnetic alloy suitable for use in combination with a rare earth cobalt magnet, and by performing dental prosthesis or orthodontics using the present alloy, (1) bridges, etc. Instead, it uses magnetic force to extend the lifespan of healthy teeth. (2) The root of the tooth can be used. (3) Removal of dentures and crowns is easy;
Easy to keep the oral cavity clean. The industrial effect is great because the following effects can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a schematic explanatory diagram of the case where a rare earth cobalt magnet and a soft magnetic alloy are used for dental purposes. 1: Gum part, 2: Root part, 3: Magnetic alloy, 4:
Crown part, 5: Rare earth cobalt magnet.

Claims (1)

[Claims] 1% by weight: 15-70% cobalt, 5-5% palladium
Dental magnetic alloy characterized by 70% gold and 10-80% gold. 2. The dental treatment according to claim 1, which further contains one or more of manganese, zinc, tin, aluminum, silicon, and magnesium in an amount of 5% or less by weight as a deoxidizing agent. Magnetic alloy for use.