JPS6256123B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Summary of the Invention The material from which the denture is manufactured by bonding tooth metal parts, particularly of noble metals or precious metal alloys, to tooth porcelain and other tooth metal parts, respectively, is 1 to 100% by weight of one or more materials. It consists of a precious metal halide and a fine precious metal component of 0 to 99% by weight. The invention also relates to methods of using such binders.

The present invention relates in particular to materials and methods for bonding tooth metal parts made of noble metals or precious metal alloys to tooth porcelain and other tooth metal parts, respectively.

In the field of denture loading technology, in particular when producing dental crowns and bridges, it is customary to cover a metal substrate with a subsequent layer of tooth porcelain, which porcelain layers are successively baked at relatively high temperatures. The metal substrate or substructure is generally a metal of the noble metal family, consisting primarily of gold. Tooth porcelain generally consists of feldspar, quartz and kaolin, which may contain small amounts of additives of other materials. A clinically satisfactory bond between the metal substrate and the porcelain depends, inter alia, on the coefficient of thermal expansion of the material used. Since porcelain is fired as layers onto a metal substrate at high temperatures and cooled to room temperature, interfacial stresses tend to develop between the individual material layers and between the metal and the porcelain. Generally, satisfactory bonding between the metal substrate and the porcelain is due to mechanical coercive forces and van der Waalska, with little, if any, chemical bonding. The cohesive forces resulting from such bonds are always weaker than true chemical bonds.

In the past, attempts have been made to provide an intermediate layer on a metal substrate prior to sintering the porcelain to improve the degree of bonding of the porcelain to the metal. For example, referring to German Published Patent Application No. 2531113,
This suggests the formation of oxides, such as tin oxide, on the metal surface before sintering. Although the oxide layer is chemically bonded to the metal substrate, it does not significantly improve the chemical bond between the porcelain and the metal, and this bond may be broken under clinical conditions.

It is also well known that surface modification of metal substrates can improve bonding. The improvement in bonding due to surface modification is primarily attributable to the increase in van der Waals forces. Furthermore, it is known that the bonding material between the metal substrate and the tooth porcelain consists primarily of pure gold powder.

The aim of the invention is to provide a clinically indestructible bond between a metal substrate and tooth porcelain and between tooth metal parts, respectively. Furthermore, the aim is to reduce the tension between the individual layers.

In order to solve these problems, the present invention provides a bonding material for obtaining a denture by bonding tooth metal parts to tooth porcelain and other tooth metal parts, respectively. 1-100% by weight of precious metal halides and 0-100% of fine precious metal components
99% by weight.

Furthermore, the present invention also relates to a method for obtaining a denture by bonding tooth metal parts mainly made of noble metals or noble metal alloys to tooth porcelain and other tooth metal parts, respectively, and this method involves applying a bonding material to a metal substrate. It is characterized in that the bonding material is used when applying and sintering or sintering at high temperature, and then applying and sintering tooth porcelain.

Although the present invention provides clinically unbreakable bonds between metal and tooth porcelain, and between two tooth metal parts, respectively, it is still unclear how this bond is formed in theory. It's not clear. Bond formation can be explained by assuming that a chemical bond is first formed between the metal substrate and the bonding material.
The bonding material then reacts with other tooth metal parts or tooth porcelain. In this last case, the tension within the porcelain is likely to decrease and a chemical bond to the porcelain itself will occur. Preferably, the binder according to the invention contains one or more noble metal halides.
~99.9% by weight and fine precious metal components 0.1~99% by weight
Contains.

The noble metal halides used are preferably chlorides and/or fluorides, but bromides and iodides can also be used. Suitable noble metal halides are silver chloride, gold chloride and/or gold fluoride.

The noble metal component may consist of a noble metal or an alloy thereof, preferred metals being gold and/or silver. Furthermore, palladium and/or platinum are also suitable, but rhodium, osmium and iridium are less preferred. The finely divided precious metal component can be used in any suitable form, such as flakes, granules or powder. The particle size of the noble metal component is preferably about 1 to 60 μm, with particle sizes of 10 μm or less being preferred. Optimal particle size is in the range of about 1-10 μm. Precious metal particles are commercially available in finely divided form or may be ground to the appropriate particle size in suitable equipment.

A noble metal component for the purposes of the present invention is defined as a metal or metal alloy containing one or more noble metal components, where the precious metal component accounts for all or substantially the majority of the weight proportion of this metal or metal alloy, i.e. other than precious metals. These elements can be present, if at all, only in small amounts. The noble metal component is: (a) particles of pure precious metal, (b) alloy particles of two or more noble metals, (c) a physical mixture of (a) and (b) above, (d) (a) above. , (b) or (c) and small amounts of base metals added as alloying components or physical mixtures.

The precious metal component preferably contains at least 50% by weight gold, while the balance is about 0-45% by weight of a metal selected from the group consisting of silver, platinum, palladium and rhodium, and zinc, iron, tin, cadmium, manganese. , about 0 to 5% by weight of a base metal selected from the group consisting of germanium, magnesium, cobalt, and nickel.

The noble metal halide component of the composition is a critical component. For example, elemental metal particles of noble metals such as gold or silver do not provide the same improved results. At present, it is not clear why precious metal halide components, alone or in combination with precious metal-based metal components, react with tooth porcelain or tooth metal components to form clinically indestructible bonds upon sintering. ,
This bond is believed to be chemical in nature and does not occur in metallic noble metal particles. Noble metal halides are commercially available in granular or crystalline form in particle size ranges within or below the desired range for the noble metal component. For example, gold chloride is commercially available as _HAuCl4 and can be used directly in this form. Also, noble metal halides can be used in 100% amounts;
Preferably, noble metals should also be used, especially gold or alloys containing a high proportion of gold. This is because it is desirable to obtain a substantial gold background on the underside of the porcelain coating.

The binder can be used with or without suitable dispersants and/or other binders. Preferably, the bonding material according to the invention is used together with a binder so that it can be easily and controllably applied to metal surfaces, for example by brushing, painting, dipping or spraying. The binder or support vehicle can preferably be removed under the action of heat, ie it should preferably burn off or volatilize without leaving any residue during the sintering process. The same applies to dispersants, for which known aqueous detergents can be used.
Suitable binders are organic substances with adhesive properties, which can also be further diluted with suitable solvents. If no dispersant or binder is used, the binder can be applied to the metal surface by any suitable method, such as by applying a powder or an aqueous or organic dispersion.

As metal substrate, customary tooth metals or tooth alloys can be used. In general, the composition of the metal substrate corresponds to the composition of the finely divided noble metal component, i.e. the metal substrate preferably includes one or more noble metals,
Composed of gold, silver, platinum or palladium.

After the bonding material is applied to the tooth metal component, optionally with a dispersant and/or binder, the bonding material is sintered in the applied portion at a temperature in the range of about 870° to 1080°C. Temperatures below or above this range may also be used, depending particularly on the composition of the binder or metal substrate. The optimum temperature range is approximately 1010°~1040°
It is ℃. The binder is typically sintered for about 1 to 25 minutes. The sintering temperature also depends on the type of noble metal halide used, ie noble metal halides can already wet the noble metal substrate at temperatures below 870°C. When making dental crowns, bridges or dentures, it is often preferred to choose a sintering temperature such that the bonding material forms only a coating of irregularly shaped particles on the metal substrate. The optimum temperature range for this purpose is about 980° to 1024°C. Thereafter, tooth porcelain is baked onto the thus treated surface. The firing temperature of tooth porcelain generally depends on its composition, but is usually within the range of about 870° to 1000°C. It is also possible to sinter the binder simultaneously with the sintering of the porcelain, but this is less preferred.

Suitable tooth metal parts to which the bonding material according to the invention can be baked include, for example, precious metal foils, preferably platinum foils. It is also possible to sinter several layers of the same or different bonding material onto the tooth metal part.

After carrying out the method according to the invention, the tooth porcelain is baked onto the precious metal substrate to form an unbreakable bond. It is believed that the sintered bond material chemically interacts with the porcelain to form an unbreakable bond. It is not entirely clear whether the noble metal chloride or fluoride itself decomposes or escapes during sintering.
However, it is clear that the noble metal halides contribute to the formation of unbreakable bonds.
For the purposes of this invention, an unbreakable bond is:
It is defined as an adhesive joint that does not cause separation of the components at the adhesive interface under clinical conditions. This involves applying sufficient impact force perpendicularly to a composite structure until the structure fractures, and then visually inspecting the fractured structure to see if separation has occurred at the interface between each member. is easily determined.

For dentures, primarily porcelain-coated cast metal crowns are used. A relatively thick metal base is created by creating a wax impression from the fabricated teeth.
The impression is embedded in a potting composition, the wax is burned off and the metal is cast into the cavity. after that,
The tooth porcelain is coated as a layer onto this metal substrate and baked. The metal used is preferably a noble metal or a noble metal alloy in which the amount of gold is predominant.

The thickness of the cast metal substrate is in the range 0.2-0.5 mm, and this metal substrate is relatively expensive due to the precious metals used. Furthermore, bulky metal substrates do not leave sufficient space for the porcelain coating.

Therefore, a mantle is preferred. This is aesthetically superior to all other dentures,
They cannot be distinguished from natural teeth. However, in most cases it can only be used on the front teeth where aesthetic considerations are the main concern. This limited use is due to the insufficient strength of the tooth porcelain used. The crown is usually made by fitting platinum foil to the root of the prepared tooth, then removing the foil and encasing it in porcelain and baking it. The platinum foil is then removed again and the mantle crown is cemented in place. According to DE 2531113, the platinum foil does not need to be removed, but remains in place to reinforce the tooth porcelain. A metal oxide layer, for example a tin oxide layer, can bond the tooth porcelain to the platinum foil.

The procedure for applying the bonding material to the noble metal substrate and the additional procedure include, of course, the use of a noble metal foil, in particular a platinum foil, as the noble metal substrate. The thickness of the model and the composition of the precious metal substrate depend on what is being fabricated (eg, whether a crown, a crown, or other prosthetic tooth).

After applying the binding material to, for example, platinum foil, it is baked and
By subsequently applying the tooth porcelain as a layer and firing it, the bonding material and method according to the invention provides a reinforced cap with a strength substantially greater than that of DE-A-2531113.

The noble metal substrate can be coated with one layer of the binder material to be fired, but it is also possible to apply and bake several layers to the substrate. If noble metal foils, especially platinum foils, are used as noble metal substrates, at least one layer is deposited, but preferably two layers or even several layers can be deposited. The total thickness of the layer depends on how the platinum foil can be processed. If the layer of bonding material is too thick, the foil will be too stiff and difficult to conform to the tooth root.

The bonding material is applied before fitting the platinum foil to the fabricated teeth.
It can also be applied to this foil and baked. Thus, platinum foil can be sold with one or several layers of sintered binder. This is also true for other suitable noble metal substrates.

If several layers are used, these do not have to be identical. One layer of precious metal halide 1-100
% and precious metals from 0 to 99%,
The other layers may be the same as the first layer or different.

The present invention will be further explained below with reference to Examples.
All percentages are by weight.

Example 1 A bonding material having the following composition was applied to a metal substrate (thin noble metal, 100% Pt).

(A) Noble metal halide: Powdered AgCl 1.4% (B) Noble metal component: Fine particles (5-10 μm) of Au
97% and Ag 0.6% and Pt 0.4% and Cu, Fe, Cr, Cd
Alloyed with 2%.

The binder was baked onto the platinum foil at 1024°C for 3 minutes. A layer of commercial tooth porcelain (manufactured by Ceramco) was then applied and fired at 969°C. The resulting composite structure was clinically indestructible.

Corresponding tests were carried out using other tooth porcelains and comparable results were obtained.

Example 2 The procedure of Example 1 was repeated with the following changes to the metal substrate.

(1) Au 87.5%, Pt 4.5%, Pd 6%, balance is trace elements (2) Au 52%, Pd 38%, Zn 4%, balance is trace elements (3) Ag 60%, Pd 40% Obtained The results were comparable to those of Example 1.

Example 3 The procedure of Example 1 was repeated except that (A) 93% AgCl and (B) the same noble metal component as in Example 1, 7%, were used. Comparable results were obtained.

Example 4 The procedure of Example 1 was repeated except that (A) 50% AgCl and (B) the same 50% noble metal component as in Example 1 were used. Comparable results were obtained.

Example 5 The procedure of Example 1 was repeated except that (A) 7% AgF and (B) 93% Au were used. The resulting composite structure was clinically indestructible.

Example 6 The procedure of Example 1 was repeated, except that only PtCl ₂ was used, ie, no noble metal component was used. Comparable results were obtained.

Example 7 The procedure of Example 1 was repeated except that (A) 10% PtCl ₂ and (B) 90% Au were used. Comparable results were obtained.

Example 8 The procedure of Example 1 was repeated, except that only HAuCl ₄ was used, ie no noble metal component was used as a binder. Comparable results were obtained.

Example 9 The procedure of Example 1 was repeated except using (A) 10% HAuCl ₄ and (B) 90% Au. Comparable results were obtained.

Example 10 The procedure of Example 1 was repeated except using (A) 5% AgCl ₂ and 5% PtCl ₂ and (B) 90% Au.
Comparable results were obtained.

Example 11 (A) 10% HAuCl ₄ and 5% PtCl ₂ and (B) 80% Au
The procedure of Example 1 was repeated except that . The remaining 5% was composed of an organic binder. Comparable results were obtained.

Example 12 A root model 18 was created from an impression of a manufactured tooth. As shown in FIG. 1, the platinum foil 10 was wrapped tightly around the root 18 to form an overlapping edge 20, which was folded back as shown in FIG. The foil should extend beyond the gingival margin 26 and form a seam 28 of sorts. Pressure was applied to the foil 10 with an instrument or by hand to press it tightly against the root 18. This was then separated from the root and a noble metal substrate was provided thereon as shown in FIG.

Applying a bonding material according to Example 8 to this metal substrate,
Baking was performed at 970°C for 5 minutes. Thereafter, several tooth porcelain layers were applied and baked onto the substrate in a known manner.

To demonstrate the strength of the finished crown, the crown was fixed to a metal root and a metal pin was brought into contact with the incisal border of the crown. A metal cylinder weighing 100 g was kept 20 cm above the metal pin and dropped from there.
No significant damage to the crown could be detected. When increasing the distance of the metal cylinder to 40 cm, the porcelain broke only in a limited area.

For comparison, the same tests were carried out on crowns made without the bonding material according to the invention. A 100g weight dropped from a height of 20cm bursts even large tooth porcelain particles.

[Brief explanation of the drawing]

1 to 3 are explanatory diagrams showing a part of the procedure of the present invention. 10...Platinum foil, 18...Root, 20...Overlapping edge, 26...Gingival margin, 28...Seam.

Claims (1)

[Scope of Claims] 1. Consisting of a noble metal or a noble metal alloy characterized by containing 1 to 100% by weight of one or more noble metal halides and 0 to 99% by weight of fine noble metal components. A bonding material for manufacturing dentures by bonding tooth metal parts to tooth porcelain and other tooth metal parts. 2. The bonding material according to claim 1, characterized in that it contains 1 to 99.9% by weight of one or more noble metal halides and 0.1 to 99% by weight of fine noble metal components. 3. The binding material according to claim 1 or 2, wherein the noble metal halide is a chloride and/or a fluoride. 4. The bonding material according to any one of claims 1 to 3, wherein the noble metal halide is silver chloride and/or gold fluoride. 5. Claims 1 to 4, characterized in that the precious metal component consists of gold and/or platinum.
The binding material described in any of the paragraphs. 6. The noble metal component contains at least 50% by weight of gold, the balance being 0 to 45% by weight of a metal selected from the group consisting of silver, platinum, palladium and rhodium;
Claims 1 to 5 consist of 0 to 5% by weight of a base metal selected from the group consisting of zinc, iron, tin, cadmium, manganese, germanium, magnesium, cobalt and nickel. The binding material described in any of the above. 7. The binding material according to any one of claims 1 to 6, further comprising a dispersant and/or another binder. 8. Binding material according to any one of claims 1 to 7, characterized in that the binding material can be removed under the action of heat. 9. Claims 1 to 8, characterized in that the particle size of the noble metal component is approximately 1 to 60 μm.
The binding material described in any of the paragraphs. 10. A method for obtaining dentures by bonding tooth metal parts, in particular of noble metals or precious metal alloys, to tooth porcelain and other tooth metal parts, respectively, which comprises applying a bonding material to a metal substrate and sintering or sintering it at high temperatures. A bonding method characterized in that a bonding material containing 1 to 100% by weight of one or more noble metal halides and 0 to 99% by weight of fine noble metal components is used. 11. The method according to claim 10, characterized in that a binder containing 1 to 99.9% by weight of one or more noble metal halides and 0.1 to 99% by weight of fine noble metal components is used. Method. 12 Claim 1, characterized in that a metal substrate mainly composed of one or more of the noble metals gold, silver, platinum, and palladium is used.
The method described in item 0. 13 The noble metal halide component is chloride and/or
The method according to any one of claims 10 to 12, characterized in that a binder made of a fluoride or a fluoride is used. 14. The method according to any one of claims 10 to 13, characterized in that a binder is used in which the noble metal halide component contains silver chloride, gold chloride and/or gold fluoride. 15. The method according to any one of claims 10 to 14, characterized in that a binder whose noble metal component contains gold, silver, platinum and/or palladium is used. 16 Precious metal component contains at least 50% by weight of gold, the balance being 0-45% by weight of a metal selected from the group consisting of silver, platinum, palladium and rhodium.
and copper, zinc, iron, tin, cadmium, manganese,
Claims 10 to 15, characterized in that a binder comprising 0 to 5% by weight of a base metal selected from the group consisting of germanium, magnesium, cobalt and nickel is used. Method. 17. A method according to any one of claims 10 to 16, characterized in that the bonding material is applied to the tooth metal part and/or tooth porcelain together with a dispersant and/or other binders. 18 Claim 1, characterized in that the binder is sintered within a temperature range of approximately 870° to 1080°C.
The method according to any one of items 0 to 17. 19. A method according to any of claims 10 to 18, characterized in that the binder is sintered for about 1 to 25 minutes. 20. A method according to any of claims 10 to 19, characterized in that the noble metal component of the binder has a particle size of about 1 to 60 μm. 21. A method according to any of claims 10 to 20, characterized in that the tooth metal part is a precious metal foil, preferably a platinum foil. 22. A method according to any one of claims 10 to 21, characterized in that several layers of the same or different bonding material are sintered onto the tooth metal part.