DD230771A1 - DENTAL PROSTHESIS AND METHOD FOR THE PRODUCTION THEREOF - Google Patents

Abstract

A dental prosthesis made from a solid corrosion-resistant metal alloy base and at least one decorative outer layer and process for its preparation. The object is to design a dental prosthesis with a decorative outer layer and a metallic base and to create such a ratio of the thickness of the layers that the denture has a longer usability compared to the monolithic prostheses of noble alloys while maintaining high medical and biological characteristics and the decorative and cosmetic properties during use. This is achieved according to the invention in that the decorative outer layer is made of a stronger material as the basis and contains nitrides, hydroxynitrides, carboxynitrides, cyano nitrides and / or monoxides of the metals of the transition group of the fourth group of the periodic table. The ratio of the strength of the decorative outer layer to the strength of the basis is 1:10 or 1: 200.

Description

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Known is the construction of a layered dental prosthesis (GB-PS 1215485), which is produced by electroplating, in which one first a layer of metal (gold, rhodium or chromium), which is compatible with tissues of the organism, and then a second layer a corrosion-resistant non-precious metal (nickel) that is slightly stronger than the first, and then precipitate the third layer of a metal (gold, rhodium or chromium) that is compatible with the body tissues. Also known is the construction of a dental prosthesis (SU-PS 212442), which consists of a metallic base of a solid corrosion-resistant metal alloy (alloy of silver and palladium) and a decorative outer layer. The outer layer is a gold based alloy that has lower strength compared to the base.

These dentures allow to reduce the consumption of precious metals by 90 to 95%. But since the thickness of the layer of precious metals on the prostheses 10 to 20μ.ηη (with larger strengths, the sense of the layered construction of the denture lost due to increased consumption of precious metals) does not exceed, wear the chewing surfaces of the prosthesis, the intense abrasion be exposed quickly (within 2 to 3 months of operation of the prosthesis) and it will lose the decorative and cosmetic effect of the denture. In addition, the destruction of the decorative outer layer of the dental prosthesis is a strong electrochemical Entedelung (change in the difference of electrical potentials by 20 to 60 mV) of the construction of the prosthesis, the emergence and an active functioning of microgalvanic cells. The latter can exert a local and generally harmful effect on the human organism. Simultaneously with this, the basis of the respective prosthesis is intensively destroyed by the microgalvanic cells, and as a result, the process of destruction of the decorative outer layer is accelerated.

Object of the invention

The aim of the invention is a dental prosthesis, which can be produced easily and inexpensively and has high performance properties.

Explanation of the essence of the invention

The invention has the object of providing a dental prosthesis with a decorative outer layer and a metallic base in such a way and to create such a ratio of the thickness of the layers that the denture a longer usability compared to the monolithic prostheses of noble alloys while maintaining high medical and biological characteristics and which allows for decorative and cosmetic properties during use.

This is inventively achieved in that the decorative outer layer is made of a stronger material as the basis and nitrides, hydroxynitrides, carboxy nitriles, cyano nitrides and / or monoxides of the metals of the subset of the fourth group of the periodic table, wherein the ratio of the thickness of the decorative outer layer to the strength of the foundation is 1:10 to 1: 200.

The base of the prosthesis is made of a solid corrosion-resistant material: stainless steel, a chrome-cobalt, chromium-cobalt-molybdenum alloy, or any other conventional metal alloy. Such a basis ensures the respective denture a high strength at variable sign loads that arise when chewing food. The basis of the dental prosthesis can be composed entirely of individual elements of the construction, which are immovably connected by means of welding or soldering.

The nitrides, hydroxynitrides, carboxy nitrides, cyano nitrides, and / or monoxides of the metals of the sub-group of the fourth group of the periodic table, from which the decorative outer layer of the dentures is made, are characterized by a high chemical resistance in acidic, alkaline and neutral media of the oral cavities, by the non-toxicity and a good compatibility with tissues of the organism. Therefore, the dentures themselves are resistant to the oral cavity media and biologically indifferent.

As a material for the decorative outer layer it is recommended to use nitrides, hydroxynitrides, carboxynitrides, cyano nitrides and / or monoxides of titanium and / or zirconium.

As the nitrides, hydroxynitrides, carboxynitrides, cyano nitrides and / or monoxides of titanium and / or zirconium produce a wide range of goldenish, gold shimmering, golden red and silver shimmering hues and shades (depending on the type of chemical compound and process parameters for their recovery ), the said compounds, when applied to metallic products, ensure the necessary decorative and cosmetic effect for these products. Thus, the zirconium nitride depending on the content of nitrogen in him a color from silvery shimmering to dark gold shimmering hue, that is, it mimics platinum or gold alloys. The titanium nitride, mixtures of titanium nitrides and zirconium nitrides, monoxides of titanium and / or zirconium and their hydroxynitrides may have golden straw, golden yellow and golden red hues and the multitude of their shades and mimic the gold of various samples and thereby extend the range of shades to be produced itself.

The hardness of the materials making up the decorative skin layer of the dentures of the invention is 10 ⁴ MPa (2200 to 2,900 kp / mm ² ), which is significantly higher than the hardness of the known metal alloys used in stomatology. Therefore, the decorative outer layer of such a prosthesis is characterized by a very high wear resistance (180 to 220 times higher than the wear resistance of a layer of galvanic gold) and allows the denture to successfully withstand the abrasion.

The increased brittleness of the materials to be used for the decorative outer layer creates boundary conditions for the ratio of the strength of the base to the outer layer. The thinner the decorative outer layer will be, the lower is its ductility. However, over-rejuvenation of this layer reduces the life of a prosthesis due to its rapid abrasion.

It has been determined exprimentally that the ratio of the thickness of the decorative outer layer to the thickness of the denture base should be 1:10 to 1: 200. For bridge or temple prostheses, the calculation of the thickness of the decorative outer layer should be based on the thinnest cross-section of the structure of a prosthesis.

The decorative outer layer of the dental prosthesis according to the invention can be one, two or more layers depending on the tasks set. In a multilayer composition of the decorative outer layer, the layers of the above-noted metal-like titanium and zirconium compound alternations may occur. The multilayer compositions of the decorative outer layer make it possible to more fully vary their adhesion properties to a base of various materials, the characteristics of the malleability and wear resistance of the decorative ones

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The dental prostheses according to the invention may extend to the following product nomenclature: individual punching and casting crowns (full crowns, equatorial crowns, half crowns, three-quarter crowns, crowns with pin), fully cast bridge-like prostheses, soldered bridge-like prostheses with cast artificial teeth and facets, cast inserts, locks for Fix dentures in periodontal disease and body pieces and arch of temple prostheses, curved and cast braces.

With insignificant damage to the decorative outer layer (presence of micropores or microcracks, local attrition) that does not degrade the decorative and cosmetic properties of the denture, as a result of filling these sites with fluids from the oral cavity, local microgalvanic cells may form between the base and the decorative outer layer arise.

The consequence of the formation of microgalvanic cells (without the introduction of special measures) is the appearance and development of corrosive foci of a much more electronegative metal of a cell, that is, the basis of the dental prosthesis. This causes the local destruction of the base under a coating, an accelerated destruction of the weakened (base missing) decorative outer layer due to mechanical effects and, ultimately, the loss of the decorative and cosmetic properties of the denture.

To increase the corrosion protection of the material of the dental prosthesis base of the invention, it is recommended that a protective layer be made of a metal that is more electronegative than the metal of the decorative outer layer and has the ability to passivate in liquid oral cavity media between the denture base and decorative outer layer Ratio of the thickness of the protective layer to the thickness of the decorative outer layer 0.3: Ibis is 1: 1.

In the presence of said protective layer, the liquid medium in the oral cavity in the case of destruction of the decorative outer layer does not gain access to the basis of the prosthesis, but to the material of the protective layer. A microgalvanic cell is created between metals of the protective layer and the decorative outer layer. The role of an anode in this cell is met by a more electronegative metal, that is, the metal of the protective layer. However, the metal of the protective layer is chosen so that it can passivate sufficiently well under conditions of anode polarization. In the area of the respective defect in the decorative skin, an anode polarization is always noted due to the difference in the electrical potentials of the metals in contact, that is, the protective layer has all the conditions for its passivation (formation of passive films). The protective layer comprising passive films does not allow the metal of this layer to be further destroyed (dissolves), thereby preventing the spread of corrosion processes.

This ensures the corrosion resistance of the prosthesis according to the invention.

As the metal for the protective layer, it is recommended to use titanium, tantalum or chromium. These metals have the ability to easily passivate themselves in media in the oral cavity, thereby preventing corrosion of the protective layer and, consequently, the base of the respective dentures.

To ensure reliable protection of the metal alloy of the denture base from corrosion, the protective layer should be completely (without through pores). As the thickness of the layer increases, the likelihood of having through pores in it decreases, so the protective layer should be made as strong as possible. However, as the thickness of the protective layer increases, the amount of work required for its precipitation increases. From this point of view, the protective layer should be made as thin as possible.

It has been found experimentally that the ratio of the protective layer to the thickness of the decorative outer layer should be 0.3: 1 to 1: 1. Lower values are taken for tantalum and titanium, larger for chrome.

The physico-mechanical characteristics (thermal linear expansion coefficient, moldability, microhardness and others) of the base and the decorative outer layer or the protective layer and the decorative outer layer differ greatly (on the multiple).

When changing the temperature control or under conditions of mechanical stress, for example during the use of a dental prosthesis, occur at the separation points of said layers concentrations of mechanical stresses. In a number of cases, this causes the decorative outer layer to peel off.

To avoid this in the dental prosthesis according to the invention, it is recommended to carry out between the base and the decorative outer layer or the protective layer, a transition layer, which is composed of titanium, tantalum or chromium in admixture with a corresponding metal nitride. The concentration of said nitrides increases in the thickness of the transition layer toward the decorative outer layer in a range of 0.01% by weight to 90 to 99.9% by weight, and the ratio of the thickness of the transition layer to the thickness of the decorative outer layer is 0.3: 1 to 1: 1.

In the transition layer, the distribution of the concentration of the metals and their nitrides ensures a gradual change in the physical-mechanical characteristics of this layer. The values of the characteristics of the transitional layer vary in magnitude from the characteristics of the base to the characteristics of the decorative outer layer.

In the dental practice, often enough soldered constructions based on a dental prosthesis are used in the manufacture of bridge-type dentures. The elements of such a construction (crowns, faceted bodies, artificial teeth) are made separately, and then they become uniform in the soldering process

^ Construction merged.

For soldering the elements of the construction of stainless steel dental prostheses, chromium-cobalt and other conventional corrosion-resistant metal alloys, inexpensive silver solders are successfully used. Most commonly silver-cadmium are (composition in wt .-%: Ag 45, Cu 25, Mn Cd 15 and 15) (having a melting point of 620-660 ⁰ C and silver-zinc solders composition in wt .-% : Ag 63, Cu 27, Zn 10 or in IVra .-%: Ag 37, Cu 38, Zn 15, Cd 0.5, Mn 5.2, Ni 4, Mg 0.3) having a melting point of 800 to 850 ^0th C used.

At the solder joints, the decorative outer layer, which is usually precipitated at 400 to SOO ⁰ C and beyond, has a low adhesion due to evaporation of individual components of the solder. This often causes the exfoliation of the decorative outer layer or the formation of cracks, pores and other defects at the solder joints of the outer layer.

Therefore, when the base of a dental prosthesis includes a brazed solid corrosion resistant metal alloy structure, it is recommended that an additional layer be applied between the outer decorative layer and the prosthetic base or prosthesis base and prosthesis base. In the first case she should

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are suitably made of cobalt, nickel, chromium, molybdenum or zirconium or nitrides of chromium or molybdenum. In the second case it is recommended to use the additional layer of cobalt, nickel, chromium, molybdenum or zirconium. In both cases, the ratio of the thickness of the additional layer to the thickness of the decorative outer layer is 0.5: 1 and 1: 1, respectively.

At a ratio of the thickness of the additional layer to the thickness of the decorative outer layer equal to 0.5: 1 to 1: 1, the additional layer has no through pores. The pore-free additional layer is a sufficiently reliable barrier not only for the liquid, but also for the vapor phase of the evaporated components of the respective solder. A greater thickness of the additional layer is unjustified due to the increase in the cost of making this layer. The presence of an additional layer on the brazed construction of a denture base makes it possible to ensure the integrity of the brazed suture, the absence of visible pores at the solder joints and, as a result, high mechanical strength of such dentures as well as high quality of their decorative outer layer also in the area of the soldered seam.

The method of manufacturing such a dental prosthesis, which provides for the fabrication of a base by soldering the elements of dentures of a solid corrosion resistant metal alloy into a unitary construction and applying a decorative outer layer with vacuum technology, is characterized in that the zone of soldered connection of the construction or the entire construction is coated before application of the decorative outer layer with a layer of cobalt, nickel, chromium, molybdenum or zirconium or nitrides of chromium or molybdenum galvanic or vacuum technology process, wherein the ratio of the thickness of the additional layer to the strength of the decorative outer layer is 0.5: 1 or 1: 1.

As mentioned above, the additional layer precludes the formation of defects in the decorative outer layer at the soldered seams and increases the mechanical strength of the soldered joint.

The dental prostheses according to the invention are in their decorative and cosmetic properties, in their biologically neutral behavior, in chemical and corrosion resistance not behind the monolithic dental prostheses, which are made of gold or from platinum alloys, and in their strength and wear resistance they surpass the latter. In this case, the dental prostheses according to the invention have good machinability and are economically advantageous. They are 10 to 15 times cheaper than the dental prostheses made from gold alloys, porcelain and metal-ceramic. The prostheses with the decorative outer layers of the present invention are resistant to saline and saliva, and to cultures of the blue-type bacteria, the gold-colored Staphylococcus, the coli bacteria, the primary trypsin-treated cultures of human embryo fibroblasts, the digestible line of HEP-2 Lines and the cells of the buccal epithelial tissue of a human indifferent.

The decorative outer layer in the dental prostheses according to the invention does not cause chromosome aberrations. The method for producing the dental prostheses according to the invention is simple in technological design, is based on known technological processes and is carried out as follows:

First of all, according to the methodology (diecasting, stamping) common in stomatology, the basis of a dental prosthesis is made of solid corrosion-resistant non-precious metal alloys (stainless steel, alloys of cobalt and chromium or of cobalt, chromium and molybdenum) in the form of molds of required shape. One checks the accuracy of their seat in the oral cavity of a patient. After fitting and fitting the scale is removed from the surface of the respective molding and it is up to a roughness of the surface R _z = 0.1 to 0.4μ, ηι polished. Then the denture base of the dental prosthesis is carefully washed in conventional technology and degreased in an ultrasonic bath.

In the known process of vacuum technology, a decorative outer layer of calculated thickness of a material is applied, which ensures the adhesion and wear resistance as well as the required hue and shading of the coating. Like, above _; mentioned, the decorative outer layer can be mono-, double- or multilayer. When applying two or more layers, the composition and pressure of the reaction gas, the substance to be evaporated and the technological parameters of the precipitation process of layers vary depending on the objects to be solved.

Thereafter, if necessary, the decorative outer layer of the respective denture is finally polished and then, if necessary, the missing elements of plastic are formed on the prosthesis.

In the case where the presence of a protective layer on the dental prosthesis is required, one of the known methods (electroplating, vacuum plasma technology) on the surface of the denture base prior to the application of the decorative outer layer, a layer of titanium, tantalum or Chrome applied in the required thickness. As mentioned above, to reduce the concentration of mechanical stresses at the interface between the denture base and the decorative outer layer or between the decorative outer layer and the protective layer, a transition layer is made. The transition layer is also deposited in a known, for example, vacuum plasma process by increasing the pressure of the nitrogen in the chamber upon precipitation of the layer. When the base of a dental prosthesis is formed from a brazed construction, an additional layer of calculated thickness of cobalt, nickel, chromium is applied to such a (brazed) dental prosthesis prior to vacuum plasma deposition of layers (protective, transition and decorative outer layers) , Molybdenum, zirconium, chromium or molybdenum nitrides precipitated.

embodiment

The invention will be explained below in more detail by way of several individual examples. Example 1 *

A dental prosthesis is made in the form of a monolithic bridge-type construction containing a chromium-cobalt alloy base with a titanium nitride decorative outer layer.

The prosthesis base in the required form is cast on a wax model of a chromium-cobalt alloy. One examines the accuracy of their seat in the oral cavity of a patient and finally adapts it. The adapted base of a dental prosthesis is polished with finely dispersed (0.5 to 1 μΐη) abrasives. After polishing, the prosthesis base is carefully washed in an ultrasonic bath with hot water (70 to 80 ° C) containing 2 to 3 wt .-% synthetic detergent. Then it is washed with running water, in a bath with gasoline and then it is in

Subsequently, the basis of a bridge-like dental prosthesis is placed in a vacuum chamber provided with a rotating device to the drum of which the prosthesis base is applied. The vacuum chamber is also provided with three titanium plasma sources which are directed to the drum of the rotary device. The evaporating substance used in all three plasma sources is chemically pure titanium.

~ DTe "V ¥ kmJnl" m "me7wrrclTis" iextending Λ 1 0 ' ⁵ Torr evacuated, the turning device (rotational speed 9 rpm) is turned on, the base is applied a negative voltage of 1.1 kV, a plasma source turned on and set in this a arc current of 80 A. Within 2 minutes, the base is completely cleaned by bombarding its surface with titanium ions, then a negative voltage of 180V is applied to the base and a second and third plasma source is turned on Arc current is 9OA in each of the three plasma sources Under these conditions, nitrogen is supplied to the vacuum chamber by adjusting the pressure in the vacuum chamber to 5 × 10 ^-3 Torr, thereby precipitating the titanium nitride decorative outer layer on the base the layer reaches a thickness of 8μΓη, the plasma sources are turned off, the supply of nitrogen is stopped, the rotating device a The negative voltage is removed from the prosthesis and after 10 minutes the prosthesis is removed from the vacuum chamber.

The decorative outer layer has a microhardness of 2 500 to 2 600 kp / mm ² , a hue that matches the color of a high-grade gold alloy, and good adhesion to the base.

The prepared prosthesis was fixed with viscous cement in the oral cavity of a patient. Observations over four years have revealed no local and general negative effects on the human organism. The prosthesis was not destroyed. The color of the prosthesis did not change.

Example 2.

A dental prosthesis is made in the form of a monolithic bridge-type construction containing a chromium-cobalt alloy base with a titanium hydroxy-nitride decorative outer layer.

The denture base is made, polished, washed and placed in the vacuum chamber as in Example 1.

The treatment of the prosthesis base takes place until the moment of feeding nitrogen into the vacuum chamber as in Example 1. Instead of nitrogen, the vacuum chamber is a mixture of nitrogen and oxygen (80 vol .-% nitrogen + 20Vol .-% oxygen) fed and a pressure of 5 × 10 ^-3 Torr in the vacuum chamber. A layer of titanium hydroxynitride precipitates on the surface of the base (decorative outer layer). If the layer has reached a thickness of 10 μ.sup.-2, the plasma sources are switched off, the supply of the gas mixture is terminated, the negative voltage is removed from the prosthesis and the rotary device is turned off. After 10 minutes, the prosthesis is removed from the vacuum chamber.

The decorative outer layer has a microhardness of 2300 kp / mm ² , a hue that matches the color of a high-grade gold alloy, and good adhesion to the base.

The prepared prosthesis was fixed with viscous cement in the oral cavity of a patient. Observations over 2 years have not revealed any local and general negative effects on the organism. The color of the prosthesis has not changed.

Example 3

A dental prosthesis is made in the form of a monolithic bridge-type construction containing a chromium-cobalt alloy base with a zirconium nitride decorative outer layer.

The denture base is made, polished, washed and placed in a vacuum chamber as in Example 1.

The vacuum chamber is provided with three plasma sources, in which zirconium serves as an evaporating substance. The ion cleaning by bombardment with zirconium ions and the application of the decorative outer layer are carried out as in Example 1. The precipitation is carried out until the production of a layer of 20μ, πη.

The prepared layer has a microhardness of 2 500 kp / mm ² , a color tone corresponding to the color of a high-grade gold alloy, and good adhesion to the base.

The prepared prosthesis was fixed with viscous cement in the oral cavity of a patient. Observations over four years have not revealed any local or general negative effects on the human organism.

Example 4

A dental prosthesis is fabricated in the form of a monolithic bridge-type construction containing a chromium-cobalt alloy base with a nitride decorative outer layer of titanium or zirconium (70 wt% titanium nitride and 30 wt% zirconium nitride).

The denture base is made, polished, washed and placed in a vacuum chamber as in Example 1.

The vacuum chamber is provided with three plasma sources, in which one zirconium and in the two remaining titanium serves as an evaporable material. The ion cleaning is carried out as in Example 1; Then a negative voltage of 200V is applied to the base, the sources of titanium and zirconium plasma are turned on, in the sources of the titanium plasma arc current values of 9OA and in the source of the zirconium plasma of 8OA are set. Thereafter, nitrogen is supplied to the vacuum chamber and its pressure is adjusted to 5x10 ^-3 Torr. At the surface of the base, the decorative outer layer is precipitated, which is composed of a mixture of titanium and zirconium nitrides (70% by weight of titanium nitride and 30% by weight of zirconium nitride). If this layer has a thickness of 12 μm, the plasma sources are switched off, the supply of nitrogen is stopped, the rotating device is stopped, the tension is removed from the dental prosthesis and after 10 minutes the denture is taken out of the vacuum chamber.

The decorative outer layer has a microhardness of 2600 kp / mm ² , a hue that matches the color of a high-grade gold alloy, as well as good adhesion to the base.

The prepared prosthesis was fixed in the oral cavity of a patient with viscous cement. Observations over four years have not revealed any local or general negative effects on the human organism. In analyzing the saliva of the patient, zirconium and titanium were not detected. The color of the prosthesis has not changed.

Example 5

A dental prosthesis is made in the form of a bridge-type monolithic construction comprising a chromium-cobalt alloy base with a decorative outer layer of a mixture of titanium and zirconium nitride (0.1% by weight zirconium nitride and 99.9% by weight). % Titanium nitride).

The denture base is made, polished, washed and placed in a vacuum chamber as in Example 1.

The vacuum chamber is provided with three plasma sources which serves as an evaporable material an alloy which is composed of 99.9 wt .-% titanium and 0.1 wt .-% zirconium.

The application of the decorative outer layer is carried out as in Example 1 until the production of a layer in a thickness of 15μ, μΐη. The prepared layer has a microhardness of 2500kp / mm ² , a hue that matches the color of a high grade gold alloy, and good adhesion to the base.

The prepared prosthesis was fixed in the oral cavity of a patient with viscous cement. Observations Over four years have not revealed any local or general negative effects on the human organism. The color of the prosthesis has not changed.

Example 6

A dental prosthesis is fabricated in the form of a monolithic bridge-type construction containing a chromium-cobalt alloy base with a decorative outer layer consisting of two layers, one of which is adjacent to the base, of a mixture of carboxy-nitrides of titanium and zirconium (67% by weight titanium carboxynitride and 33% by weight zirconium carboxynitride) and the second composed of titanium nitride.

The denture base is made, polished, washed and placed in a vacuum chamber as in Example 1.

The vacuum chamber is provided with three plasma sources, in which zirconium and in the remaining two titanium serves as an evaporable material. The ionic cleaning of the base is carried out as in Example 1.

Then a negative voltage of 200V is applied to the base, the plasma sources of titanium and zirconium are turned on, and a arc current in each of the plasma sources is set at 9OA each. Then, a mixture of nitrogen, oxygen and methane (80% by volume of nitrogen, 10% by volume of oxygen and 10% by volume of methane) is fed to the vacuum chamber, the pressure in the vacuum chamber being 10 10 ^-3 Torr is set. The first layer of the decorative outer layer, which is composed of a mixture of the titanium carboxynitrides and zirconium (67% by weight of titanium carboxyloxynitride and 33% by weight of zirconium carboxynitride), is deposited on the surface of the base.

When this layer has reached a thickness of 6 / xm, the plasma source of zirconium is turned off, the supply of the gas mixture is adjusted and nitrogen is supplied, the pressure of which in the vacuum chamber is set at 5 × 10 ^-3 Torr. The second layer of the decorative outer layer of titanium nitride is deposited.

If the layer of titanium nitride has reached a thickness of 3 μ, ιτ), the plasma sources are switched off, the supply of nitrogen is stopped, the negative voltage is removed from the prosthesis and the rotary device is brought to a standstill. After 10 minutes, the prosthesis is removed from the vacuum chamber.

The produced decorative outer layer has a microhardness of 2600kp / mm ² , a color corresponding to the color of the high grade gold alloys, and a good adhesion to the base.

The prepared denture was fixed in the oral cavity of a patient with Visphat cement. Observations over two years have not revealed any local or general negative effects on a patient's organism. The color of the prosthesis has not changed.

Example 7

A dental prosthesis is made in the form of a momolithic bridge-like construction containing a base of a chromium-cobalt alloy with a decorative outer layer composed of two layers, one of which is adjacent to the ^ GTun ^ made of titanium ynamite nitride and the second of titanium oxynitride.

The prosthesis base is manufactured, polished, washed and placed in a vacuum chamber as in Example 1.

The denture base is machined until the moment of introduction of nitrogen into the vacuum chamber as in Example 1. Instead of nitrogen, a mixture of nitrogen and acetylene (95 vol.% Nitrogen and 5 vol.% Acetylene) is fed to the vacuum chamber wherein the pressure in the vacuum chamber in the amount of 8 × 10 ^-4 Torr is set. In this case, a layer of titanium ynamite nitride is deposited on the surface of the base. After this layer has been deposited to a thickness of 5 / xm, the feed of the gas mixture is stopped and a gas mixture of nitrogen and oxygen (90% by volume of nitrogen and 10% by volume of oxygen) is returned by reducing the pressure in the vacuum chamber is set at the level of 6 × 10 ^-3 Torr and the titanium oxynitride layer is deposited. When the layer of titanium oxynitride has reached a thickness of 5 μm, the plasma sources are switched off, the supply of the gas mixture is stopped, the negative voltage is removed from the prosthesis and the rotary device is brought to a standstill. After 10 minutes, the prosthesis is removed from the vacuum chamber.

The decorative outer layer produced has a microhardness of 2400 kp / mm ² , a color that matches the color of the high-grade gold alloys, and good adhesion to the base.

The prepared denture was fixed in the oral cavity of a patient with Visphat cement. Observations over 2 years have not revealed any local or general negative effects on the patient's organism. The color of the prosthesis has not changed.

Example 8

A dental prosthesis is made in the form of a monolithic bridge-type construction containing a chromium-cobalt alloy base with a decorative outer layer composed of two layers, one of which is adjacent to the base, titanium monoxide and the like second consists of titanium nitride.

The denture base is made, polished, washed and placed in a vacuum chamber as in Example 1.

The processing of the basis of the dental prosthesis takes place until the moment of feeding nitrogen of the vacuum chamber also as in Example 1.

Instead of nitrogen, the vacuum chamber oxygen is supplied by the pressure in the amount of 5 10 ^-4 Torr is set.

In this case, a layer of titanium monoxide is deposited on the surface of the base. When this layer has reached a thickness of 5μ.η, the supply of oxygen is stopped and nitrogen is supplied to the vacuum chamber by adjusting the pressure in the chamber to 5 × ¹ CT ³ Torr, thereby precipitating the second layer of titanium nitride. When the layer of titanium nitride has reached a thickness of 5 / xm, the plasma sources are switched off, the supply of nitrogen is stopped, the negative voltage is removed from the prosthesis and the rotary device is brought to a standstill. After 10 minutes, the prosthesis is removed from the vacuum chamber.

The decorative outer layer produced has a microhardness of 2500kp / mm ² , a color corresponding to the color of the high grade gold alloys, and good adhesion to the denture base.

The prepared denture was fixed in the oral cavity of a patient with Visphat cement. Observations over two years have not revealed any local or general negative effects on a patient's organism.

Example 9

A denture is made in the form of a monolithic bridge-like construction comprising a chromium-cobalt alloy base with a decorative outer covering of a mixture of titanium and zirconium nitrides (33% by weight zirconium nitrides and 67% by weight titanium nitrides) and Contains a protective layer of titanium.

The base of the dental prosthesis is fabricated, polished, washed and placed in a vacuum chamber as in Example 1. The ion cleaning of the prosthesis base is carried out by bombardment with titanium ions as in Example 1. Then, a negative voltage of 200V is applied to the prosthesis base, the second plasma source turned on with titanium, therein set a arc current of 80 A and a protective coating of titanium in a thickness of 3μιτ \ dejected. Then, the third plasma source is turned on with zirconium, a arc current in all three plasma sources of 90 A is set, and nitrogen is supplied to the vacuum chamber by adjusting the pressure to the level of 5 × 10 ^-3 Torr. A decorative outer layer of a mixture of titanium and zirconium nitrides is precipitated. When this layer has reached a thickness of 10 / tm, the plasma sources are switched off, the supply of gas is stopped, the negative voltage is removed from the prosthesis and the rotary device is brought to a standstill

 Technical and medical characteristics of the dental prosthesis correspond to the characteristics given in Example 4.

Example 10

A denture in the form of a single crown of stainless steel with a decorative outer layer of titanium nitride and a protective layer of tantalum is made. A cylindrical hollow body made of stainless steel is heated to a temperature of 800 to 900 ⁰ C and punched out the required shape for the production of the molding of a crown. Then, the high-temperature annealing of the molding, while the accuracy of the seat is checked the respective molding on the tooth stump and it is finally adapted to the position of the teeth when biting a counter-tooth. Subsequently, the scale is removed from the crown molding by dipping it into a solution having the following composition (g / l): sulfuric acid 100, nitric acid 150, hydrofluoric acid 30. The molding is held in this solution until the scale is completely removed (20 to 60 s). Thereafter, the crown molding is washed in running water, dried and polished with finely dispersed (0.5 to 1 μΐη) abrasives. The prosthesis base prepared is washed in an ultrasonic bath with hot water (70 to 8O ⁰ C) containing 3 wt .-% of synthetic detergent, and then washed with gasoline and ethyl alcohol. Then, the prosthesis foundation is mounted in a vacuum chamber on the drum of a rotary device. The vacuum chamber is provided with three plasma sources, in which one tantalum and in the other two titanium serves as an evaporable substance. ... ,

The vacuum chamber is evacuated to a pressure of 1 × 10 ^-5 Torr, the rotating device turned on, a negative voltage of 800V to the denture base, turned on the tantalum plasma source and set an arc current of 200 A therein.

The ion cleaning is carried out by bombarding the prosthesis base with tantalum ions for a period of 2 min. Then, a negative voltage of 50 V is applied to the denture base and a protective layer of tantalum is deposited. If the protective layer has reached a thickness of 3μ, Γη, the two titanium plasma sources are turned on and a total arc current of 90 A is set, the tantalum plasma source is switched off, a negative voltage of 180 V is applied to the prosthesis base and nitrogen is fed to the vacuum chamber. by adjusting the pressure in the vacuum chamber at 5 × 10 ^-3 Torr. In this case, a decorative outer layer of titanium nitride is deposited. When this layer has reached a thickness of 9 / cm, the plasma sources are switched off, the supply of nitrogen is stopped, the negative voltage is removed and the rotary device is brought to a standstill. After 10 minutes, the prosthesis is removed from the vacuum chamber.

The prepared denture has a microhardness of 2500kp / mm ² , a color matching the color of the high grade gold alloys, and a high wear resistance (190 times higher than gold alloys). The prepared denture was fixed in the oral cavity of a patient with viscous cement. Observations over four years have not revealed any local or general negative effects on a patient's organism. The color of the prosthesis has not changed.

Example 11

A dental prosthesis is made in the form of a brazed bridge-type construction comprising a stainless chromium-nickel-based and a silver-cadmium solder with a protective layer of chromium and a decorative outer layer of titanium and zirconium nitride (0.5 wt. % Zirconium nitride and 9.9 wt% titanium nitride).

Crown moldings of the bridge-type denture are prepared as in Example 10. Then, after a wax model, the intermediate part of the prosthesis (facets and artificial teeth) is cast and by means of soldering with silver-cadmium solder a uniform basic construction of the bridge-like prosthesis is made. Afterwards, the scale is removed, the denture is polished and washed as in Example 10.

Then the base is dipped in a galvanic bath for applying the protective layer of chromium.

As the aqueous electrolyte for chromium plating, the following composition (g / l) is used: chromic anhydride 250 and sulfuric acid 2.5. The precipitation is carried out at a temperature of the electrolyte of 60 ° C and a current density of 50 A / dm ² . Under the conditions mentioned, the protective layer of chromium is allowed to precipitate in a thickness of 8 / xm.

Then, the prosthesis base is polished with the protective coating of chromium with finely dispersed diamond pastes, washed with gasoline and ethyl alcohol in an ultrasonic bath containing hot water containing 3% by weight of synthetic detergent.

Thereafter, the prosthesis base is mounted in a vacuum chamber on the drum of a rotating device. The vacuum chamber is provided with three plasma sources in which an alloy of titanium with zirconium (0.5 wt% zirconium and 99.5 wt% titanium) serves as the vaporizable substance

The ion cleaning of the prosthesis base is carried out by bombardment with titanium and zirconium ions and the application of the decorative outer layer of a titanium and Zirkoniumnitridgemisch in a thickness of 8 / xm as in Example 1.

The prosthesis produced has the same technical and medical characteristics as the prosthesis in Example 5.

Example 12

A dental prosthesis is fabricated in the form of a monolithic bridge-type construction containing a chromium-cobalt alloy base with a titanium oxynitride decorative outer layer and a transition layer of a titanium and titanium nitride mixture. The denture base is made, polished, washed and placed in a vacuum chamber as in Example 1.

The vacuum chamber is provided with three plasma sources containing titanium as an evaporable substance.

The ion cleaning of the prosthesis base is carried out as in Example 1.

Then a negative voltage of 200V is applied to the prosthesis base, the other two plasma sources are turned on, the arc current is set in each case in the amount of 8OA, the vacuum chamber is fed nitrogen by the pressure gradually from 1 10 ~ ⁵ Torrauf 1 10 ~ ⁴ Torr during the entire time of precipitation of the transition layer in a thickness of 6μπ \ is brought. The content of titanium nitride in the transition layer increases in thickness from 0.01% by weight to 90% by weight.

When the transition layer has reached a thickness of 6 / xm, the supply of nitrogen is stopped and a mixture of nitrogen and oxygen (85% by volume of nitrogen and 15% by volume of oxygen) is fed in by the pressure of 5 × 10 ^-3 Torr is set. This leaves a decorative outer layer to precipitate in a thickness of 25μηη.

The technical and medical characteristics of the prosthesis produced correspond to the characteristics mentioned in Example 2.

Example 13

A denture is made in the form of a monolithic bridge-type construction comprising a chromium-cobalt alloy base with a titanium and zirconium nitride (50 wt% titanium nitride + 50 wt% zirconium nitride) outer sheath decorative layer and a transition layer of a titanium nitride Tantalum and tantalum nitride mixture contains. The prosthesis base is made, polished, washed and placed in a vacuum chamber as in Example 1. The vacuum chamber is provided with three plasma sources, in which one tantalum, the second titanium and in the third zirconium is used as an evaporable substance.

The lonenreinigung carried out as in Example 10. Then, a negative voltage of 100 V is applied to the Prothes'engrundlage and the vacuum chamber nitrogen supplied by the pressure gradually whole of 1 x 10 ^-6 Torr to 8 · 10 "" * Torr during the Time of precipitation of the transition layer is brought in a strength of 4jum. The content of tantalum nitride in the transition layer increases from 0.01% by weight to 95% by weight. If the transition layer has reached a thickness of 4μΐη, the plasma sources are switched on with titanium and zirconium, the arc current is set at 90 A, the plasma source is switched off with tantalum, and the negative voltage of 250 V is applied to the denture base. Nitrogen is then added to the vacuum chamber by adjusting the pressure to the level of 4 × 10 ^-3 Torr and allowing the decorative outer layer of titanium and zirconium nitride mixture to precipitate. When this layer has reached a thickness of 9 / .mu.m, the plasma sources are switched off, the supply of nitrogen is stopped, the negative voltage is removed from the prosthesis and the rotary device is brought to a standstill. After 10 minutes, the prosthesis is removed from the vacuum chamber

The technical and medical characteristics of the prosthesis produced correspond to the characteristics mentioned in Example 6.

Example 14

A dental prosthesis is made in the form of a brazed bridge-type construction containing a base of stainless chromium nickel steel and silver-zinc braze with a titanium nitride decorative outer layer and a transition layer of chromium and chromium nitride mixture.

The denture base is prepared and washed as in Example 11. Then, the prosthesis base is mounted in a vacuum chamber on the drum of a rotating device. The vacuum chamber is provided with three plasma sources in which one chromium and in the other two titanium serves as an evaporable substance.

The vacuum chamber is evacuated to a pressure of 1 x 10 ~ ^s Torr, turned on the rotary device, a negative voltage of 700V to the denture base and the lonenreinigung 4min performed long.

Then a negative voltage of 30 V is applied to the prosthesis base, in the plasma source, a sheet flow of 90 A is set and fed to the vacuum chamber nitrogen. The pressure of the nitrogen is gradually brought from 1 × 10 ^-5 Torr to 3 10 ~ ⁴ Torr during the whole time of the precipitation of the transition layer in a thickness of 4 / jm. The concentration of chromium nitride increases in the thickness of the transition layer from 0.01% by weight to 90% by weight. The microhardness of this layer increases from 400 kp / mm ² to 2 600 kp / mm ² . If the transition layer has reached a thickness of 4μ.ιη, two titanium plasma sources are switched on, it is set in a sheet current of 9OA, a negative voltage of 180 V applied to the prosthesis base and turned off the chromium plasma source. Nitrogen is then fed to the vacuum chamber by adjusting the pressure to the level of 5 × 10 ^-3 Torr and allowing the titanium nitride decorative outer layer to precipitate to a thickness of 10 / μm. If this layer has reached a thickness of 10 / xm, the plasma sources are switched off, the supply of nitrogen is stopped, the voltage is removed from the prostheses and the rotary device is brought to a standstill

 The prosthesis produced has technical and medical characteristics that correspond to the characteristics mentioned in Example 1.

Example 15

A dental prosthesis is made in the form of a brazed bridge-type construction containing a stainless chromium-nickel steel and silver-zinc-solder base with a zirconium nitride decorative outer layer, a chromium and chromium nitride transition layer, and a chromium protective layer ,

The denture base is prepared and washed as in Example 11.

Then, the prosthesis base is mounted in a vacuum chamber on the drum of a rotating device.

The vacuum chamber is provided with three plasma sources, in which one chromium and in the other two zirconium serves as an evaporable substance.

The ion cleaning of the prosthesis base takes place as in Example 14.

Then, a negative voltage of 30V is applied to the base, a 90A arc current is set in the plasma source, and a chromium protective layer of 4μιη thickness is deposited.

After reaching the predetermined thickness of the protective layer, the transition layer is allowed to precipitate as in Example 14.

The precipitation of the decorative outer layer is carried out as in Example 14 only with the difference that zirconium is used as an evaporable substance.

The decorative outer layer produced has a microhardness of 2500 kp / mm ² , a color corresponding to the color of a high-grade gold alloy, and a good adhesion of the layers to one another and to the prosthesis base.

The prosthesis was fixed in the oral cavity of a patient with viscous cement. Observations over four years have not revealed any local or general negative effects on a patient's organism.

Example 16

A dental prosthesis is fabricated in the form of a monolithic bridge-type construction comprising a chromium-cobalt alloy base with a decorative outer splint composed of a layer of the titanium carboxynitride and a layer of the titanium oxynitride with a transition layer of a titanium and titanium nitride mixture and a protective layer of titanium.

The denture base is prepared, polished and placed in a vacuum chamber as in Example 1. The vacuum chamber is provided with three plasma sources in which titanium serves as an evaporable substance. The ion cleaning of the prosthesis base is carried out as in Example 1.

Then, a negative voltage of 180A is applied to the denture base, the remaining two plasma sources are turned on, set therein a current of 8OA each arc and deposited the protective layer in a thickness of 6 / xm. Then, the transition layer is made of a titanium and Titannitridgemisch as in Example 12 with the difference in the precipitation that the pressure of the nitrogen at 7 x 10 ~ ⁴ Torr is increased. This, in turn, increases the content of titanium nitride at the boundary to the decorative outer layer to 99% by weight. When the transition layer has reached a thickness of 6 / xm, the supply of nitrogen is stopped, the arc current in the plasma sources is brought to 90 A, and a mixture of nitrogen, methane and oxygen (85% by volume nitrogen, 10% by volume oxygen and 5 vol % Of methane) was fed to the vacuum chamber, the pressure in the vacuum chamber was set at 2 × 10 ^-3 Torr, and the first layer of the titanium carboxynitride decorative outer layer was precipitated. If this layer has reached a thickness of 3μηι, the supply of the gas mixture is stopped and a gas mixture of nitrogen and oxygen (90% nitrogen + 10% oxygen) supplied by the pressure of this mixture in the amount of 5 10 ~ ³ Torr is set, and then the second layer of the decorative outer layer of titanium oxynitride is precipitated. If this layer has reached a thickness of 3 μm, the plasma sources are switched off, the supply of gas mixture is stopped, the negative voltage is removed from the prosthesis and the rotary device is brought to a standstill. After 10 minutes, the prosthesis is removed from the vacuum chamber.

The prepared prosthesis has a microhardness of 2500 kp / mm ² , a good adhesion between the layers and with the basis and color of a high quality gold alloy.

The prosthesis was fixed in the oral cavity of a patient with Visphat cement. Observations over two years have not revealed any local or general negative effects on a patient's organism. _The color of the prosthesis has not changed. _

Example 17

A dental prosthesis in the form of a brazed bridge-like construction is made, comprising a base of stainless chromium-nickel steel and silver-cadmium solder with a decorative outer layer of a titanium and zirconium nitride mixture (67 wt .-% titanium nitride and 33 wt. % Zirconium nitride) and with an additional layer of cobalt.

The denture base is prepared and washed as in Example 11.

Then the prosthesis base is immersed in a galvanic bath for applying the additional layer of cobalt. As the aqueous solution for applying the layer, the following composition (g / 1) is used: cobalt sulfate 500, sodium chloride 17 and boric acid 45. The precipitation of the additional layer of cobalt is carried out at a current density of 3 A / cm ² , the temperature of the electrolyte is 45 ° C and the pH 4. The additional cobalt layer is deposited in a thickness of 8μ.Γπ.

Then the prepared prosthesis base is polished with the additional layer of cobalt with finely dispersed pastes. Thereafter, the denture base is washed and placed in the vacuum chamber as in Example 1.

Then the decorative protective outer layer is deposited as in Example 9, the precipitation takes place until reaching a 25μ.ιτι strong layer. If the decorative outer layer has reached a thickness of 25μ.ιη, the process of Niederschiagens is terminated as in Example 9.

Technical and medical characteristics of the prosthesis produced correspond to the characteristics mentioned in Example 4.

Example 18

A dental prosthesis in the form of a brazed bridge-type construction is made, comprising a base of stainless chromium-nickel steel and silver-cadmium solder with a decorative outer layer of titanium oxynitride and an additional layer of molybdenum.

The denture base is prepared and washed as in Example 11.

Then, the base is mounted in a vacuum chamber on the drum of a rotating device.

The vacuum chamber is provided with three plasma sources in which one molybdenum and in the other two titanium serves as an evaporable substance.

The vacuum chamber is evacuated to a pressure of 2 × 10 ^-5 Torr, the rotating device turned on, a negative voltage of 600 V on the basis turned on, the molybdenum-plasma source, set an arc current of 130 A and the lonenreinigung the denture base 3 minutes long performed. Then a negative voltage of 25V is applied to the base and the additional layer of molybdenum is precipitated.

Thereafter, the titanium plasma sources are turned on, a 90A arc current is set therein, the molybdenum plasma source is turned off, and a 200V negative voltage is applied to the base with the additional layer of molybdenum. Then, a gas mixture of nitrogen and oxygen (80% by volume of nitrogen and 20% by volume of oxygen) is supplied to the vacuum chamber by adjusting the pressure therein to the level of 5 × 10 ^-3 Torr, and the decorative outer layer of titanium oxynitride in a thickness of 15 / xm knocked down.

Technical and medical characteristics of the prosthesis correspond to the characteristics mentioned in Example 2.

Example 19

A denture is made in the form of a brazed bridge-type construction comprising a stainless chromium-nickel steel and silver cadmium solder prosthesis base with a titanium and zirconium nitride decorative outer layer (3 wt% titanium nitride and 70 wt% zirconium nitride ) and an additional layer of zirconium.

The denture base is prepared, polished and washed as in Example 11.

Then, the base in the vacuum chamber is attached to the drum of a rotary device.

The vacuum chamber is provided with three plasma lines, in which one zirconium serves as an evaporative substance in one titanium and in the other two.

The vacuum chamber is evacuated to a pressure of 1 x 10 ^"s Torr, turned on the rotary device, a negative voltage of 900 V on the basis turned on the zirconium-plasma source by an arc current of 80 A is set. For For 3 minutes, the prosthesis base is ion cleaned by bombarding it with zirconium ions, then a negative voltage of 50 V is applied to the base, the second plasma source is switched on with zirconium by adjusting the arc current therein to 80 A, and the additional layer of zirconium in a thickness of 3μΐη deposited.Then the decorative outer layer of the titanium and Zirkoniumnitridgemisch is deposited.

Technical and medical * characteristics of the prosthesis correspond to the characteristics mentioned in Example 6.

Example, 20

A dental prosthesis is made in the form of a brazed bridge-type construction containing a base of stainless chromium-nickel steel and silver-cadmium solder of a decorative zirconium nitride outer layer and an additional layer of molybdenum nitride.

The denture base is prepared, polished and washed as in Example 11.

Then, the base is mounted in a vacuum chamber on the drum of a rotating device.

The vacuum chamber is provided with three plasma sources, in which one molybdenum and in the other two zirconium serves as an evaporable substance.

Then, the vacuum chamber is evacuated to a pressure of 2 × 10 ^-6 Torr, turned on the rotary device, a negative voltage of 600 V on the basis turned on, the molybdenum-plasma source by an arc current in the amount of 130A is set therein. For a period of 3 minutes, the ion cleaning of the base is done by bombarding it with molybdenum ions.

Then, a negative voltage vo.n 25V is applied to the basis of supplied nitrogen of the vacuum chamber, by its pressure in the amount of 8 TO ^"4 Torr is set, and depressed the additional layer of molybdenum to a thickness of 5μνη. If the additional layer reached a thickness of δμ, ηη, the zirconium plasma sources are turned on by adjusting a current of 9OA in each, the molybdenum plasma source is switched off, a negative voltage of 200V is applied to the base and nitrogen is fed to the vacuum chamber, By adjusting a pressure of 4 × 10 ^-3 Torr, a decorative layer of zirconium nitride is deposited in a thickness of 15 μm.

The produced decorative outer layer has a micro hardness of 2500kp / mm ² , the color of the high quality gold alloys and a good adhesion.

The prosthesis was fixed in the oral cavity of a patient with Visphat cement. Observations over three years have not revealed any local and general negative effects on the patient's organism. This prosthesis has its color

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-11- 253 992 6

Example 21

A dental prosthesis is made in the form of a brazed bridge-type construction comprising a stainless chromium-nickel steel and silver-zirconium solder base with a titanium nitride decorative outer layer, a chrome and chromium nitride transition layer and an additional layer of nickel ,

The denture base is prepared, polished and washed as in Example 11.

Then the prosthesis base is immersed in a galvanic bath for applying the additional layer of nickel. The following composition (g / l) is used as the aqueous solution for applying this layer: nickel sulphate 300, magnesium sulphate 50, sodium chloride 10 and boric acid 30. The layer is applied at a temperature of the electrolyte of 40 ° C., a current density of 3 A / dm ² and a pH of 4.0.

After the application of the additional layer in a thickness of 4μηη the prosthesis is washed with running water and polished.

Then, the prosthesis base is mounted in a vacuum chamber on the drum of a rotating device.

The vacuum chamber is provided with three plasma sources in which one chromium and the other two titanium serve as an evaporable substance. Then the transition layer of chromium and chromium nitride mixture is deposited in a thickness of 5 / xm as in Example 14.

Then the decorative outer layer of titanium nitride deposited in a thickness of 8μπι / The precipitation is terminated as in Example 1. After 10 minutes, the prosthesis is removed from the vacuum chamber.

The prosthesis produced has the same technical and medical characteristics as the prosthesis described in Example 1.

Example 22

A dental prosthesis is made in the form of a brazed bridge-type construction containing a base of stainless chromium-nickel steel and silver cadmium solder with a decorative outer layer composed of two layers, one of which abuts the denture base , from a mixture of the titanium nitrile zirconium and zirconium (67% by weight titanium cyano nitrite and 33% by weight zirconium cyanogen nitride) and the second from a mixture of the nitrides of titanium and zirconium (67% by weight titanium nitride and 33% by weight). Zirconium nitride) and an additional layer of chromium.

The denture base is prepared and washed as in Example 11.

Then the base is immersed in a galvanic bath and the additional layer of chromium deposited in a thickness of 5 / xm as in Example 11.

Then the denture base with the applied additional layer is polished, washed and placed in a vacuum chamber as in Example 11. The vacuum chamber is provided with three plasma sources in which one zirconium and two other titanium serve as an evaporable substance.

The ionic cleaning of the base with the additional layer of chromium is carried out by bombardment with zirconium ions as in Example 6.

Then, the transition layer of the titanium and titanium nitride mixture is precipitated as in Example 12.

Then, a negative voltage of 220 V is applied to the base, the titanium plasma sources are turned on and a arc current of 90 A is set in all three plasma sources. Then, a gas mixture of nitrogen and acetylene (90Vol .-% nitrogen and 10 vol .-% acetylene) is fed to the vacuum chamber, the pressure in the vacuum chamber in the amount of 1 · 10 ~ ³ Torr adjusted and the first layer of the decorative outer layer in a Thickness of 9 / xm knocked down.

After the predetermined thickness is reached, the supply of the gas mixture is stopped, nitrogen is supplied to the vacuum chamber by adjusting the pressure in the vacuum chamber to be 5 10 ^-3 Torr, and the second layer of the decorative outer layer is made of the mixture of nitrides of titanium and titanium Zirconium deposited in a thickness of 4 / xm.

Technical and medical characteristics of the prosthesis produced correspond to the characteristics of the prosthesis mentioned in Example 7.

Example 23

A dental prosthesis is made in the form of a brazed bridge-type construction containing a base of stainless chromium-nickel steel and silver-cadmium solder with a decorative outer layer composed of two layers, one of which abuts the base , from a mixture of the monoxides of titanium and zirconium (33% by weight of titanium oxynitride and 67% by weight of zirconium oxides) and the second of a mixture of monoxide nitrides of titanium and zirconium (33% by weight of titanium oxynitride and 67% by weight of zirconium oxynitride); provided with an additional layer of chromium nitride.

The denture base is prepared and washed as in Example 11.

The base is then mounted in a vacuum chamber on the drum of a rotating device.

The vacuum chamber is provided with four plasma sources, in which one chromium, the second titanium and in the third and fourth zirconium serves as an evaporable substance. The vacuum chamber is evacuated to a pressure of 2-10 ~ ⁵ torr, the rotator is turned on, a negative voltage of 700V is applied to the base, the chromium plasma source is turned on and a 8OA arc current is set therein. For 4 minutes, the ion cleaning of the base is done by bombarding it with chromium ions.

Thereafter, a negative voltage of 30Van is applied to the base, nitrogen is supplied to the vacuum chamber by adjusting the pressure to be 5 × 10 -5 Torr, and the additional layer of chromium nitride is deposited to a thickness of 4 / μm reaches the predetermined thickness, the two zirconium plasma sources and the titanium source are turned on by setting a 90A arc current therein, the chromium plasma source is turned off, and a negative voltage of 200V is applied to the base with the additional coating of chromium nitride.

Then, the supply of nitrogen into the vacuum chamber is stopped by supplying oxygen at a pressure of 3 × 10 ⁴ torr and the first layer of the decorative outer layer of the titanium and zirconium monoxide mixture (33% by weight of titanium monoxide and 67% by weight). Zirconium monoxide) in a thickness of 4μ.ιη deposited. Thereafter, the supply of oxygen is stopped and a gas mixture of nitrogen and oxygen (82 vol .-% nitrogen and 18 vol .-% oxygen) supplied by the pressure in the vacuum chamber in the amount of 5 10 ~ ³ Torr is set and the second Layer of the decorative outer layer of the mixture of oxynitrides of titanium and zirconium deposited in a thickness of 6 / jm.

The produced decorative outer layer has a microhardness of 2200kp / mm ² , a good adhesion with the transition layer and a color corresponding to the color of a high grade gold alloy.

The prosthesis was fixed in the oral cavity of a patient with Visphat cement. Observations over two years have not revealed any local or general negative effects on the patient's organism. The layer on the prosthesis was not destroyed, the color of the prosthesis has not changed.

Example 24

A dental prosthesis is fabricated in the form of a monolithic bridge-type construction containing a chromium-cobalt alloy base with a decorative outer layer composed of three layers, one of which being the base, titanium tannin nitride, the second titanium oxynitride and the third titanium nitride.

The denture base is prepared, polished, washed and placed in a vacuum chamber as in Example 1. The vacuum chamber is provided with three plasma sources containing titanium as an evaporable substance.

The ionic cleaning of the base is carried out by bombardment with titanium ions as in Example 1.

Then, a negative voltage of 220V is applied to the base, the plasma sources are turned on by setting therein a current of 9OA each. Thereafter, a gas mixture of nitrogen and acetylene is (90 vol .-% nitrogen and 10 vol .-% acetylene) is supplied to the vacuum chamber, the pressure of the mixture is adjusted in the amount of 5 x 10 ^-4 Torr, and the first layer of the decorative outer layer of Titanium cyano nitride deposited in a thickness of 4μητι.

Then, the supply of the gas mixture is stopped and a mixture of nitrogen and oxygen (82 vol .-% nitrogen and 18 vol .-% oxygen) supplied to the vacuum chamber by the pressure in the vacuum chamber in the amount of 1 × 10 ^-3 Torr set and the second layer of the decorative outer layer of titanium oxynitride deposited in a thickness of 4 / xm

Thereafter, the supply of the gas mixture is stopped and nitrogen is supplied by adjusting its pressure to the level of 5 × 10 ^-3 Torr, and depositing the third layer of the decorative outer layer of titanium nitride to a thickness of 5 μm.

The decorative outer layer produced has a microhardness of 2 500 kp / mm ² , a high adhesion to the base and a color corresponding to the color of a high-grade gold alloy.

The prosthesis is fixed in the oral cavity of a patient. Observations over two years have not revealed any local or general negative effects on the patient's organism. The color of the prosthesis has not changed.

No destruction of the layer was observed.

In the overwhelming majority of the dental prosthesis design variants of the present invention, sufficiently comprehensive and thorough medical biological investigations have been made which go beyond the limits of clinical investigations.

The investigations were mainly conducted in the following main directions:

1. Hygienic-chemical examination by examining the migration of the metals of a dental prosthesis in model media.

2. Examination of the action of the substance of the layers and their composition in the prosthesis on microorganisms, microflora of the oral cavity and the development of the cultures of a living tissue.

3. Hystological and hystochemical examination of the reaction of the tissue of an organism around the implant with the coating to be examined (material).

4. Investigation of the functional state of the organism of animals with an implant:

- characteristics of the state of general responsiveness;

- dynamics of the mass of a body;

- amount of hystamine in the blood;

- content of vitamin C in the blood;

- resistance to functional loads;

- condition of the central nervous system;

- liver and kidney function.

5. Hystological and hystochemical examination of internal organs (liver, kidneys, spleen, heart, adrenals).

6. Clinical investigations of the dental prosthesis structures according to the invention.

In most of the designs of the dentures of the invention, the listed program of research has been completed in full and with positive results. At other types of constructions the program is in a degree step with positive prospects.

Claims (9)

-1- 253 992 6 Invention claim: A dental prosthesis consisting of a base of a solid corrosion-resistant metal alloy and at least one decorative outer layer, characterized in that the decorative outer layer is made of a stronger material as the basis and nitrides, hydroxynitrides, carboxy nitrides, cyano nitrides and / or metal monoxides of the subgroup of the fourth Group of the Periodic Table, wherein the ratio of the thickness of the decorative outer layer to the thickness of the base 1:10 or 1: 200. 2. Denture according to item 1, characterized in that it contains as a material for the decorative outer layer nitrides, hydroxynitrides, Carboxynitride, Zyannitride and / or zirconium monoxides. 3. Denture according to item 1 and 2, characterized in that between the prosthesis base and the decorative outer layer, a protective layer is provided of a metal that is more electronegative than the material of the decorative outer layer and passivated in liquid media of the oral cavity, the ratio of the Thickness of the protective layer to the thickness of the decorative outer layer is 0.3: 1 and 1: 1, respectively. 4. dental prosthesis according to item 3, characterized in that it contains as the metal of the protective layer of titanium, tantalum or chromium. 5. Denture according to item 1 and 2, characterized in that between the decorative outer layer and the prosthesis base, a transition layer is provided, consisting of titanium, tantalum or chromium in admixture with a corresponding nitride with changing the concentration of the nitride in the thickness of Transition layer in a range of 0.01 to 90-99.9 wt .-%, wherein the ratio of the thickness of the transition layer to the thickness of the decorative outer layer is 0.3: 1 or 1: 1. 6. Dental prosthesis according to item 3 and 4, characterized in that between the decorative outer layer and the protective layer, a transition layer is provided, which consists of titanium, tantalum or chromium in admixture with a corresponding nitride with changing the concentration of the nitride in the thickness of Transition layer in a range of 0.01 to 90-99.9 wt .-%, wherein the ratio of the thickness of the transition layer to the thickness of the decorative outer layer is 0.3: 1 or 1: 1. 7. denture according to item 1 and 2, characterized in that in a prosthesis base of soldered elements of a solid corrosion-resistant metal alloy between the decorative outer layer and the prosthesis base an additional layer of cobalt, nickel, chromium, molybdenum or zirconium or chromium or Molybdenum nitrides is provided, wherein the ratio or the thickness of the additional layer to the thickness of the decorative outer layer is 0.5: 1 and 1: 1, respectively. 8. Denture according to item 5, characterized in that in a prosthesis base of brazed elements of a solid corrosion-resistant metal alloy between the transition layer and the prosthesis base an additional layer of cobalt, nickel, chromium, molybdenum or zirconium is provided, wherein the ratio of the thickness of the additional Layer to the thickness of the decorative outer layer is 0.5: 1 and 1: 1, respectively. A method of manufacturing a dental prosthesis according to item 7, which provides for the fabrication of a base by soldering together elements of the dental prosthesis of a solid corrosion resistant metal alloy into a unitary construction and applying the decorative outer layer in the vacuum technology process, characterized in that the zone of solder joint of the Before applying the decorative outer layer, the construction or the entire construction is coated with an additional layer of cobalt, nickel, chromium, molybdenum, or zirconium or chromium or molybdenum nitride, galvanically or by vacuum technology, the ratio of the thickness of the additional layer to Thickness of the decorative outer layer is 0.5: 1 and 1: 1, respectively. Field of application of the invention The invention relates to a dental prosthesis based on a solid corrosion-resistant metal alloy and at least one decorative outer layer and a method for the production thereof. Characteristic of the known technical solutions Monolithic metal dental prostheses, which are usually produced either from alloys of the precious metals gold, platinum and palladium, or from various corrosion-resistant steels or alloys, are known. In the first case, metal dentures have a high biologically neutral behavior and high decorative and cosmetic properties. However, these prostheses are not durable due to low wear resistance of precious metal alloys. In the second case precious metals are saved and the longevity of the dentures is guaranteed. However, the dentures made of corrosion-resistant steels or alloys lag behind the former in their biologically neutral behavior and in their aesthetic properties. Depending on the materials used, a distinction is made between the following types of non-removable dentures: - of porcelain and metal ceramics; - Of metal alloys with a low content of precious metals; - layered construction of dental prostheses, when a precious metal is used only as an outer layer (coating) of the respective dental prosthesis. The production of metal-ceramic structures is complicated. Porcelain crowns have high decorative and aesthetic properties and are mainly used for restoring frontal teeth. But they are not sufficiently strong due to the brittleness of porcelain. In alloys with a lower content of noble metals, it is not possible to bring the content of precious metals below 40 to 60% without greatly deteriorating their biologically neutral behavior. Solid dental prostheses with high medical and biological characteristics can only be produced by significantly reducing the consumption of precious metals during their production (by 80 to 95%). At present, however, these dentures can not be widely used because high medical and biological characteristics as well as decorative and aesthetic properties of the dental prostheses can only be maintained within 2 to 3 months of their operation.