KR20230114014A - Biocompatible coating method for dental metal materials - Google Patents

Abstract

The present invention relates to a biocompatible coating method for dental metal materials that can fix the position of teeth without irritating the human body by coating the surface of metal parts used for orthodontic treatment. The present invention provides a biocompatible coating method for dental metal materials comprising the following steps: (a) etching and activating the surface by immersing the dental metal material in an acidic solution; (b) coating rhodium on the surface of the etched and activated dental metal material; and (c) cleaning and drying the rhodium-coated dental metal material.

Description

Biocompatible coating method for dental metal materials}

The present invention relates to a biocompatible coating method for a dental metal material, and more particularly, to a dental metal material capable of fixing the position of teeth without stimulation to the human body by coating the surface of a metal part used for orthodontic treatment. It relates to a biocompatible coating method of

In general, malocclusion is an occlusion relationship in which the arrangement of teeth is not aligned or the upper and lower meshing state is out of the normal position for some reason, resulting in aesthetic or functional problems. It is to treat malocclusion so that the mouth and teeth can fully fulfill their roles for reasons such as chewing, correct pronunciation, and improvement of oral hygiene and aesthetic reasons.

Treatment of malocclusion uses various devices and methods depending on the cause or treatment period. There are devices designed to eliminate habits, devices that inhibit or promote the growth of the upper and lower jawbones, and devices that slowly move teeth to a desired position. It can also be divided into detachable fixed devices. Each device is used alone or in parallel according to the purpose of treatment.

Common orthodontic methods include a lingual orthodontic method in which orthodontic brackets (see FIGS. 1 and 2) are attached to the inside of the teeth and installed so as to contact the tongue, and an orthodontic bracket is attached to the outside of the teeth and installed so as to contact the lips. It is classified as medial orthodontic method. Recently, lingual orthodontic method has been activated for aesthetic reasons, but due to limitations in terms of treatment effect and completeness of correction, medial orthodontic method is implemented in principle rather than lingual orthodontic method.

In the case of orthodontic treatment using the internal orthodontic method, the brackets must be attached to the teeth without being arbitrarily detached during the orthodontic period, and also must not damage the tooth surface when detached after orthodontic treatment is completed.

Conventional orthodontic brackets can be manufactured in various shapes using metal, ceramic, resin, etc. Any shape basically serves as an attachment surface where the back side is directly attached to the teeth, and a plurality of brackets are attached to the outer surface opposite to the back side. Slots are formed into which orthodontic wires connecting to each other are inserted.

In order to perform orthodontic treatment using these orthodontic brackets, the practitioner first applies adhesive to a certain portion of the tooth surface to be corrected, and then, before the adhesive completely solidifies, the entire attachment surface of the bracket to the tooth surface to which the adhesive is applied. After attaching, align the position of the bracket so that the wire can be easily inserted into the slot and wait until the adhesive is completely solidified.

Thereafter, when the adhesive is completely solidified, the operator inserts the wire into the slot (141 in FIG. 1, 2111 in FIG. 2) formed on the outer surface of the plurality of brackets attached to the teeth, and connects both ends of the wire to a support member fixed to the molars, etc. Support and fix to complete the installation of the orthodontic bracket.

When the installation of the plurality of brackets is completed as described above, the wires inserted into the slots of the plurality of brackets apply tension necessary for orthodontic treatment to the teeth.

In general, in the case of the bracket used in the internal orthodontic method, the surface attached to the teeth (130 in FIG. 1, 2120 in FIG. 2) is made of plastic or ceramic to prevent damage to the teeth, but in the case of such plastic or ceramic Since it is easily damaged by contact with the wire and friction, a metal slot or fixing part (120 in FIG. 1 and 220 in FIG. 2) is formed on the contact surface with the wire to fix the wire. However, in the case of a slot or a fixing part made of the metal, it may corrode at a high speed depending on the environment within the section, and may cause an allergic reaction due to oxidation and elution of the metal, so research is being conducted to improve this.

(0001) Republic of Korea Patent No. 10-1039680 (0002) Republic of Korea Patent No. 10-1591015

In order to solve the above problems, the present invention is to provide a biocompatible coating method of dental metal materials that can fix the position of teeth without stimulation to the human body by coating the surface of metal parts used for orthodontics. .

In order to solve the above problems, the present invention is (a) immersing a dental metal material in an acidic solution to etch and activate the surface; (b) coating rhodium on the surface of the dental metal material after the etching and activation are completed; and (c) washing and drying the rhodium-coated dental metal material.

In one embodiment, the acidic solution is hydrofluoric acid (HF), hydrochloric acid (HCl), perchloric acid (HClO ₄ ), chloric acid (HClO ₃ ), hypochlorous acid (HClO), acetic acid (CH ₃ COOH), sulfuric acid (H ₂ SO ₄ ), sulfurous acid (H ₂ SO ₃ ), nitric acid (HNO ₃ ), nitrous acid (HNO ₂ ), phosphoric acid (H ₃ PO ₄ ), hydrogen iodide (HI), iodine acid (HIO ₃ ), bromic acid (HBr), oxalic acid (H ₂ C ₂ O ₄ ), arsenic acid (H ₃ AsO ₄ ), chloroacetic acid (CH ₂ ClCOOH), formic acid (HCOOH), benzoic acid (C ₆ H ₅ COOH), hydrazoic acid (HN ₃ ), propionic acid (CH ₃ CH ₂ COOH), carbonic acid (H ₂ CO ₃ ), hydrogen sulfide (H ₂ S), hydrocyanic acid (HCN), chromic acid (H ₂ CrO ₄ ), trifluoromethanesulfonic acid (CHF ₃ O ₃ S), methanesulfonic acid (CH ₃ SO ₃ H), trifluoroacetic acid (CF ₃ COOH), trichloroacetic acid (CCl ₃ COOH), citric acid (C ₆ H ₈ O ₇ ), n-butanesulfonic acid (C ₄ H ₉ SO ₃ H), camphorsulfonic acid (C ₁₀ H ₁₆ SO ₄ ), tosylic acid, poly(4-styrenesulfonic acid), poly(vinylsulfonic acid), poly(styrene-alt-maleic acid), poly( acrylic acid) and poly(methacrylic acid).

In one embodiment, the acidic solution contains 50 to 1000 parts by weight of 30 to 50% by weight of hydrochloric acid, 80 to 120 parts by weight of 10 to 30% by weight of acetic acid, and 100 parts by weight of 50 to 60% by weight of hydrofluoric acid. -20% sulfuric acid 280-330 parts by weight mixture; Alternatively, it may be a mixture of 50 to 1000 parts by weight of 30 to 50% by weight of hydrochloric acid and 50 to 1000 parts by weight of 55 to 70% by weight of nitric acid based on 100 parts by weight of water.

In one embodiment, the acidic solution may further include a metal salt compound.

In one embodiment, the metal salt compound may include one or more selected from the group consisting of iron chloride, nickel chloride, copper chloride, zinc chloride, manganese chloride, chromium chloride, silver chloride, cobalt chloride, ammonium fluoride, and potassium permanganate. .

In one embodiment, the step (b) comprises preparing a rhodium plating solution by mixing 0.1 to 5 g/L of rhodium sulfate and 1 to 30 ml/L of 90 to 98 vol% sulfuric acid in water; immersing a dental metal material, which has been etched and activated, into the rhodium plating solution; Injecting a metal ball into the rhodium plating solution in which the dental metal material is immersed; Connecting an electrode to the rhodium plating solution in which the dental metal material and the metal ball are immersed, then plating for 1 to 20 minutes under a voltage of 0.1 to 30V and a current of 0.1 to 10A; and removing the rhodium plating solution and then separating the metal ball from the dental metal material.

In one embodiment, the plating step comprises: primary plating for 1 to 10 minutes under a voltage of 0.1 to 1.5V and a current of 0.1 to 0.3A; and performing secondary plating for 1 to 10 minutes at a voltage of 1.8 to 30V and a current of 0.4 to 10A.

In one embodiment, the metal ball is made of iron, copper, aluminum, nickel, gold, silver, titanium, or an alloy thereof, has a diameter of 3 to 10 mm, and has a diameter of 2 to 2 ~5 times the number can be input.

In one embodiment, the rhodium may form a rhodium layer having a thickness of 0.1 to 0.5 μm or a microstructure of rhodium having a size of 8 nm to 10 μm on the surface of a dental metal material.

The biocompatible coating method for dental metal materials according to the present invention performs rhodium coating on the surface of dental metal materials to minimize corrosion of metal materials in the oral cavity while minimizing inflammation in the oral cavity due to oxidation or elution of the metal It is possible to provide a biocompatible coating method for dental metal materials that can be used.

1 shows the shape of a conventional orthodontic bracket.
Figure 2 shows the shape of another conventional orthodontic bracket.
3 is an optical micrograph of the surface of a dental metal material according to an embodiment of the present invention.
Figure 4 is a SEM picture of a dental metal material according to an embodiment of the present invention.
5 is a TEM photograph of a dental metal material according to an embodiment of the present invention.
6 is a TEM photograph of a dental metal material according to another embodiment of the present invention.
7 is an analysis of the microstructure formed on the surface of a dental metal material according to another embodiment of the present invention.
8 is an EDS analysis result according to another embodiment of the present invention.
9 is an optical micrograph of the surface of a dental metal material according to a comparative example of the present invention.
10 shows metal dissolution test results according to an embodiment and a comparative example of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail. In describing the present invention, if it is determined that a detailed description of related known technologies may obscure the gist of the present invention, the detailed description will be omitted. Throughout the specification, singular expressions shall be understood to include plural expressions unless the context clearly dictates otherwise, and terms such as “comprise” or “have” refer to the described feature, number, step, operation, or component. However, it should be understood that it does not preclude the possibility of existence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof. . In addition, in performing a method or manufacturing method, each process constituting the method may occur in a different order from the specified order unless a specific order is clearly described in context. That is, each process may occur in the same order as specified, may be performed substantially simultaneously, or may be performed in the reverse order.

Since the present invention can apply various transformations and have various embodiments, specific embodiments will be exemplified and described in detail in the detailed description. However, this is not intended to limit the present invention to specific embodiments, and should be understood to include all conversions, equivalents, or substitutes included in the spirit and scope of the present invention.

The technology disclosed herein is not limited to the implementations described herein and may be embodied in other forms. However, the implementations introduced herein are provided so that the disclosed content is thorough and complete and the technical idea of the present technology can be sufficiently conveyed to those skilled in the art. In the drawing, in order to clearly express the components of each device, the size of the components, such as width or thickness, is shown somewhat enlarged. In the description of the drawings as a whole, it has been described from the viewpoint of an observer, and when one element is referred to as being located on top of another element, this means that the one element is located directly on top of another element or that additional elements may be interposed between them. include In addition, those skilled in the art will be able to implement the spirit of the present invention in various other forms without departing from the technical spirit of the present invention. In addition, like reference numerals in a plurality of drawings denote elements that are substantially the same as each other.

In this specification, the term 'and/or' includes a combination of a plurality of recited items or any one of a plurality of recited items. In this specification, 'A or B' may include 'A', 'B', or 'both A and B'.

The present invention comprises the steps of (a) etching and activating the surface of a dental metal material by immersing it in an acidic solution; (b) coating rhodium on the surface of the dental metal material after the etching and activation are completed; and (c) washing and drying the rhodium-coated dental metal material.

Dental metal materials are generally used for orthodontic purposes, and are devices used to even out the arrangement of teeth by fixing teeth and moving them at a slow speed. Since it must be used, it is required to have high corrosion resistance. In the case of a bracket used for orthodontic treatment (see FIGS. 1 and 2), the entirety may be made of metal, but the part in contact with the teeth (130 in FIG. 1, 2120 in FIG. 2) is made of polymer resin or ceramic, and then , Some parts including the fixing part (120 in FIG. 1 and 220 in FIG. 2) for fixing the wire are made of metal. In particular, when the entire bracket is made of metal, since it has a unique color and luster of metal, aesthetics may be deteriorated during orthodontic treatment, so after making some parts that require appreciation and elasticity as described above, It is made of polymer resin or ceramic similar to the color of teeth, and it satisfies both rigidity and aesthetics.

Existing dental metal materials are manufactured using stainless steel or titanium to increase corrosion resistance due to the nature of orthodontic devices used for a long time in the oral cavity. In the case of, processing is difficult and the strength is weak, so it is used in a limited way only in some fields. In addition, in the case of titanium, since it is manufactured in blackish gray, it has a disadvantage that it is more aesthetically inferior than the stainless steel.

In order to improve this, a dental metal material having high corrosion resistance by coating or plating the surface of the metal with chromium or nickel has been developed and used. However, in the case of the chromium or nickel, it is necessary to improve this in that it can cause inflammation due to a metal allergic reaction in many people when in contact with the mucous membrane in the oral cavity. In accordance with the need for such improvement, a technique for coating the surface of the dental metal material with ceramic has been developed. However, in the case of ceramics, the durability of dental metal materials may be lowered due to low bonding with the dental metal materials, and in the case of ceramic materials, since they have brittleness due to high hardness, they are eliminated from the dental metal materials, resulting in dental use. Corrosion of metal materials may occur.

In the case of the present invention, rhodium may be coated and used to prevent corrosion of the dental metal material. Since rhodium has high corrosion resistance and can form a matte grayish-white layer when coated on a metal surface, aesthetics can also be greatly improved.

In addition, the dental metal material of the present invention can be made of various materials and then coated with rhodium. At this time, the dental metal material may be made of iron, aluminum, nickel, copper, tin, gold, silver or titanium, and preferably may be made of nickel so that existing equipment can be used as it is. In the case of the nickel, since it has a high affinity with the rhodium coating of the present invention and is known to have high corrosion resistance, the rhodium coating of the present invention can minimize damage and detachment, as well as minimize damage and detachment even when damage and detachment occur. It can retain corrosion resistance. In addition, since the nickel has a metallic luster, unlike rhodium plated, it can be easily found when the rhodium coating is damaged or dropped.

Etching and surface activation may be performed by immersing the dental metal material prepared as described above in an acidic solution. Through this step, bonding between the dental metal material and the rhodium layer to be described later may be increased. Looking at this in detail, two kinds of reactions can be performed on the dental metal material immersed in the acidic solution. The first reaction is an etching reaction in which the surface of the dental metal material is finely etched to increase surface roughness. When the surface roughness of the dental metal material is increased through this process, the contact area with the rhodium layer is increased, so that adhesion can be improved. In addition to the etching, surface activation may occur when an acidic material contacts the dental metal material. In the case of this surface activation, it means that some of the molecules present on the surface of the dental metal material are ionized or combined with hydrogen, etc. there is. The increased adhesion due to etching and surface activation can prevent the rhodium from being removed due to impact or friction, and as a result, the durability of the dental metal material can be improved.

In addition, surface treatment through physical polishing was previously performed for coating of dental metal materials. In the case of existing dental metal materials, surface roughness is formed through physical polishing to improve the adhesion of the plating layer. Accordingly, there is a high possibility that foreign substances may be attached or deposited on the surface when using dental metal materials. However, in the case of the present invention, the surface roughness can be precisely controlled through chemical etching, which means that the roughness of the surface is very low after the coating is completed, and as a result, the adhesion of foreign substances can be minimized. In particular, in the case of dental metal materials used in the oral cavity, when grooves are formed on these surfaces, not only foreign substances but also plaque or calculus may be deposited on these parts, so it is very important to remove these grooves to prevent inflammation and infection in the oral cavity. do.

To this end, the acidic solution is hydrofluoric acid (HF), hydrochloric acid (HCl), perchloric acid (HClO ₄ ), chloric acid (HClO ₃ ), hypochlorous acid (HClO), acetic acid (CH ₃ COOH), sulfuric acid (H ₂ SO ₄ ), Sulfurous acid (H ₂ SO ₃ ), nitric acid (HNO ₃ ), nitrous acid (HNO ₂ ), phosphoric acid (H ₃ PO ₄ ), hydrogen iodide (HI), iodine acid (HIO ₃ ), hydrobromic acid (HBr), Oxalic acid (H ₂ C ₂ O ₄ ), arsenic acid (H ₃ AsO ₄ ), chloroacetic acid (CH ₂ ClCOOH), formic acid (HCOOH), benzoic acid (C ₆ H ₅ COOH), hydrazoic acid (HN ₃ ), propionic acid ( CH ₃ CH ₂ COOH), carbonic acid (H ₂ CO ₃ ), hydrogen sulfide (H ₂ S), hydrocyanic acid (HCN), chromic acid (H ₂ CrO ₄ ), trifluoromethanesulfonic acid (CHF ₃ O ₃ S), Methanesulfonic acid (CH ₃ SO ₃ H), trifluoroacetic acid (CF ₃ COOH), trichloroacetic acid (CCl ₃ COOH), citric acid (C ₆ H ₈ O ₇ ), n-butanesulfonic acid (C ₄ H ₉ SO ₃ H), camphorsulfonic acid (C ₁₀ H ₁₆ SO ₄ ), tosylic acid, poly(4-styrenesulfonic acid), poly(vinylsulfonic acid), poly(styrene-alt-maleic acid), poly(acrylic acid) and poly (Methacrylic acid) may contain one or more selected from the group. In the case of the present invention, the coating shape of the rhodium may be determined according to the type of acid used for etching and the amount of electric power used for plating, which will be described later.

Looking at this in detail, when the amount of hydrofluoric acid is increased and sulfuric acid and acetic acid are used, surface roughness and surface activation may be increased. At this time, when the amount of power used during plating is increased, it is possible to form a rhodium layer by uniformly plating the rhodium on the surface of the dental metal material. However, when the amount of hydrofluoric acid is reduced and nitric acid is used instead of sulfuric acid and acetic acid, roughness may be less increased and surface activation may be lowered. At this time, when plating is performed using a low amount of power, the rhodium may form a microstructure on the surface of the dental metal material. This will be described later.

In order to form the rhodium layer as described above, the acidic solution is 50 to 60% by weight of hydrofluoric acid 100 parts by weight, 30 to 50% by weight of hydrochloric acid 50 to 1000 parts by weight, 10 to 30% by weight of acetic acid 80 to 120 parts by weight A mixture of 280 to 330 parts by weight and 5 to 20% by weight of sulfuric acid may be used. Within the above range, proper roughness can be formed and surface activation can be excellent. However, if the range is less than the above range, the hydrofluoric acid content is relatively high and the surface roughness is increased, resulting in a rough surface of the dental metal material, In addition, as the content of sulfuric acid and acetic acid is lowered, the surface activity is lowered, and the adhesion of rhodium may be lowered. In addition, when the above range is exceeded, the content of the Buddha image is relatively low, and as desired roughness is not formed, adhesion may be reduced. In addition, in the case of the hydrochloric acid, it is more preferable that 80 to 120 parts by weight is used.

In order to form the rhodium microstructure, a mixture of 50 to 1000 parts by weight of 30 to 50% by weight of hydrochloric acid and 50 to 1000 parts by weight of 55 to 70% by weight of nitric acid based on 100 parts by weight of water may be used as an acidic solution. When used in a ratio exceeding the above range, since the amount of nitric acid increases, surface roughness increases, making it difficult to form a microstructure. When used below the above range, surface roughness decreases, resulting in poor adhesion and formation of a microstructure. this can be difficult In addition, in the case of hydrochloric acid and nitric acid, it is more preferable to use 180 to 220 parts by weight and 560 to 750 parts by weight.

In addition, in the case of the acidic solution, various acids having a pKa of -11 to 13 may be used alone or in combination. In the case of the acidic solution, it is used to etch the dental metal material, and preferably has an appropriate pKa value according to the type and size of the dental metal material. Therefore, it is possible to etch the dental metal material to a desired roughness by selecting and using an appropriate acid solution among acids having an appropriate pKa or by mixing and using the acid solution.

In addition, in the case of highly corrosive acids such as hydrochloric acid, nitric acid, and dispersion among the acids contained in the acidic solution, they can be directly used as the acid for performing the etching, but additionally, other acids are included as catalysts, thereby increasing the efficiency of the etching and surface activation. It is also possible to increase At this time, in the case of the acid included as the catalyst, it is possible to activate the surface during the etching and additionally supply hydrogen ions consumed at the same time so that etching and surface activation can occur efficiently, and also remove metal ions eluted by etching. and can play a role in maintaining the pKa.

In addition, in the case of the acidic solution, a metal salt compound may be further included. The metal salt compound refers to a salt produced by reacting a metal with an acid or an oxidizing agent, and may function as a kind of catalyst that assists and accelerates the etching and surface activation by being included in the acidic solution. In this case, the metal salt compound may include at least one selected from iron chloride, nickel chloride, copper chloride, zinc chloride, manganese chloride, chromium chloride, silver chloride, cobalt chloride, ammonium fluoride, and potassium permanganate, preferably iron chloride or chloride May contain nickel.

In addition, the above etching and surface activation steps may be performed by immersing the dental metal material in the acidic solution for 3 to 10 minutes. If the immersion is performed for less than 3 minutes, the etching and surface activation may not be performed smoothly, and the adhesion of the rhodium layer may decrease, and if the immersion is performed for a time exceeding 10 minutes, excessive etching is performed. Since the surface of the material becomes rough, foreign matter may be deposited.

In addition, the etching and surface activation steps may be performed immediately after manufacturing the dental metal material, but may be performed before or after physical polishing to improve the efficiency of surface treatment. In the case of chemical etching and surface activation of the present invention, as described above, fine surface etching is possible and surface roughness can be precisely increased. Therefore, after fabricating the dental metal part, it is possible to perform primary surface treatment through physical polishing, and then perform chemical etching and surface activation according to the present invention to increase manufacturing efficiency. In the case of physical polishing used at this time, gas or liquid is used as a carrier, and any one of emery, silicon carbide, silicon nitride, and aluminum oxide can be used as the polishing powder, but it is not limited thereto, and polishing powder of other materials can be used. can In addition, the carrier is a material that allows the abrasive powder to be sprayed at a constant speed and pressure. When a liquid carrier is used, a volatile liquid such as ethanol, methanol, isopropyl alcohol, or carbon tetrachloride may be used, and the gas carrier If used, an inert gas such as nitrogen, helium, neon, argon, or xenon may be used.

A degreasing and washing step may be further included before the etching and activating step. The degreasing and washing step is a step of degreasing and washing the surface of the dental metal material to remove foreign substances on the surface so that the coating with rhodium, which will be described later, is smoothly performed. The dental metal material may be manufactured through cutting and bending processes, and at this time, lubricating oil, cutting oil, cooling water, etc. may be contacted for processing. However, if such a processing liquid remains on the surface, it may interfere with rhodium coating, and may also accelerate the removal of rhodium by being located between rhodium and dental metal materials during rhodium coating.

Therefore, in the case of the present invention, it is possible to minimize defects caused by foreign substances by degreasing and washing the dental metal material.

The degreasing and washing step includes a degreasing step of immersing the dental metal material in a degreasing solvent and then supplying ultrasonic waves for 1 to 400 minutes to remove foreign substances and lipids on the surface; After the degreasing step, a cleaning step of immersing the dental metal material in a cleaning solvent and supplying ultrasonic sound for 1 to 400 minutes; and drying the surface of the dental metal material after the washing is completed.

The degreasing step is a step of removing foreign substances including lipids present on the surface of the dental metal material, and may be performed using a degreasing solvent and ultrasonic waves instead of a basic substance generally used in the conventional degreasing step. In the case of the dental metal material of the present invention, it is manufactured on the premise that it is used in the oral cavity, and an etching step using an acid may be performed after the degreasing step. Therefore, if a basic solution is used during degreasing, inflammation may occur in the oral cavity or etching may not be performed smoothly due to the remaining basic solution. Therefore, in the case of the present invention, degreasing is performed using a degreasing solvent, and ultrasonic waves may be supplied to increase the efficiency of such degreasing. The degreasing solvent used at this time can be used without limitation as long as it can perform the degreasing as described above, but preferably a volatile solvent or an organic solvent may be used, and most preferably ethanol. In the case of the volatile solvent, since it can volatilize and disappear at a rapid rate after performing the above degreasing, it is possible to minimize the washing time of the washing step to be described later, and in the case of the organic solvent, the organic solvent and the organic compound such as the lubricating oil or cutting oil Since it has excellent affinity, it can show high degreasing efficiency.

The ultrasound used at this time is preferably supplied at a frequency and intensity capable of resonating with lipids and foreign substances attached to the surface of the dental metal material or vibrating the dental metal material to remove foreign substances on the surface. To this end, the ultrasonic wave has a frequency of 20 to 60 kHz and may be supplied at an intensity of 100 to 600 W. Generally sold ultrasonic cleaners perform cleaning using a frequency of 26 to 28 kHz. However, in the case of the dental metal material of the present invention, various foreign substances are attached to it, and since the dental metal material can have various shapes and sizes, it is better to increase the range of change in the frequency so that these foreign substances can be more effectively removed. desirable. Therefore, the ultrasonic waves used in the present invention may have a frequency of 20 to 60 kHz, and more preferably, 25 kHz, 40 kHz, and 60 kHz are sequentially generated at regular time intervals to effectively remove and degrease various foreign substances. It is preferable. In addition, when the frequency of the ultrasonic wave is less than 20 kHz, foreign matter is not effectively removed, and when it exceeds 60 kHz, heat is generated due to resonance, so care is required. In addition, the ultrasound may be supplied for 1 to 400 minutes, preferably 100 to 150 minutes, at an intensity of 100 to 600 W. If it is supplied for less than the intensity or for less than the time, the degreasing is not smooth, and if it is supplied in excess of the intensity or for a time exceeding 400 minutes, it is uneconomical because there is no further effect.

Washing may be performed after degreasing is completed as described above. The cleaning step may be performed by immersing the dental metal material in a cleaning solvent and supplying ultrasonic sound for 1 to 400 minutes, preferably 30 to 100 minutes. The ultrasonic wave used at this time may be the same as the ultrasonic wave used in the degreasing step, and accordingly, the number of devices used may be reduced, making it more economical. In addition, in this cleaning step, foreign substances remaining in the dental metal material, which were eliminated in the degreasing step, may be removed, and in addition, volatile solvents or organic solvents used in the degreasing step may be removed. Therefore, the cleaning solvent used in the washing step is used in a larger amount than the degreasing solvent in the degreasing step, so that the reattachment of the degreasing solvent and foreign substances can be prevented. That is, the ratio of the volume of the washing solvent to the volume of the degreasing solvent is preferably 1:1 to 5:1. When the volume ratio is less than 1:1, the amount of distilled water is insufficient and the degreasing solvent and foreign matter may be reattached, and when the volume ratio exceeds 5:1, the consumption of expensive cleaning solvent increases, which is uneconomical.

In addition, the washing solvent may use polar, non-polar and organic solvents capable of performing the washing as described above, preferably water, distilled water, pure water, ultrapure water, isopropyl alcohol, carbon tetrachloride or liquid carbon dioxide may be used, and most preferably Preferably, distilled water may be used.

After the etching and activation are completed, rhodium may be coated on the surface of the dental metal material. As described above, rhodium is a metal having high corrosion resistance to bodily fluids such as saliva, and when used for the dental metal material, the dental metal material may have high corrosion resistance. However, since rhodium has a higher price than precious metals such as gold or platinum, it is difficult to manufacture and use the entire dental metal material with rhodium. In the present invention, the surface of the dental metal material is coated and used. It is possible to minimize the price increase while increasing the corrosion resistance of metal materials.

Existing dental metal materials were manufactured using nickel having high corrosion resistance on the surface in order to increase corrosion resistance, or nickel was plated on the surface of the dental metal material. However, in the case of nickel, many people have a metal allergy, and accordingly, when used as a dental metal material, it has a disadvantage that it can cause inflammation in the oral cavity. However, in the case of rhodium, it is known that such an allergic reaction is relatively low, and when the surface of the dental metal material is coated with rhodium, it is possible to minimize inflammation in the oral cavity while having high corrosion resistance.

To this end, the step (b) comprises preparing a rhodium plating solution by mixing 0.1 to 5 g/L of rhodium sulfate and 1 to 30 ml/L of 90 to 98 vol% sulfuric acid in water; immersing a dental metal material, which has been etched and activated, into the rhodium plating solution; Injecting a metal ball into the rhodium plating solution in which the dental metal material is immersed; Connecting an electrode to the rhodium plating solution in which the dental metal material and the metal ball are immersed, then plating for 1 to 20 minutes under a voltage of 0.1 to 30V and a current of 0.1 to 10A; and removing the rhodium plating solution and then separating the metal ball from the dental metal material.

A plating solution is used to plate the rhodium, and the plating solution used at this time is 0.1 to 5 g/L of rhodium sulfate in water, preferably 1.0 to 5 g/L and 1 to 30 ml/L of sulfuric acid at 90 to 98 vol%, preferably It may be prepared by mixing at a rate of 5 to 30 ml / L. At this time, the water used in the plating solution may be simply purified water, but it is preferable to use water from which foreign substances or ions are removed, such as distilled water, pure water, or ultrapure water to prevent contamination by foreign substances or ions. In addition, when the rhodium sulfate is included in less than 0.1 g / L, smooth coating may be difficult. ) and causes defects, so it is uneconomical. In the case of sulfuric acid, it is included as an electrolyte in the water, and when it is included in less than 1 ml / L, the amount of current passing through the water is inadequate, which may make it difficult to smoothly coat. It can corrode the surface of the surface and increase the roughness undesirably. Also, in the case of the sulfuric acid, it may be used to adjust the pH of the plating solution, and in this case, an amount to maintain a constant pH may be added. In particular, in the case of pH at this time, it is preferable to properly adjust the pH by adding an appropriate amount of sulfuric acid after adding the rhodium sulfate.

After the plating solution is prepared as described above, a dental metal material that has been etched and activated may be immersed in the rhodium plating solution. Therefore, it is preferable that the plating solution is prepared and used in a sufficient amount to immerse the dental metal material, and more preferably, the amount that occupies 1.5 to 3 times the volume of the dental metal material occupied in the plating bath. can be used Through this, the dental metal material can be completely immersed in the plating solution, and plating can be performed multiple times due to a sufficient amount of the plating solution, and also the rhodium sulfate and sulfuric acid consumed by additionally adding the rhodium sulfate and Uniform plating is possible even when plating is performed multiple times by replenishing sulfuric acid.

As described above, after the immersion of the dental metal material is completed, the metal ball may be put into the plating solution. The metal ball serves as an electrode of the dental metal material, and in the case of the dental metal material of the present invention, since the size is very small, conventional electrodes cannot be used, so it is better to use a method different from conventional plating. desirable. In the case of the existing plating method, a plurality of electrodes are installed on a cathode or an anode, an object to be plated is connected to the electrode one by one, and then the object connected to the electrode is immersed in a plating solution to perform plating. In this case, plating is generally not performed on the portion where the electrode is connected. However, in the case of the dental metal material of the present invention, the size is very small, and as described above, unplated portions (voids) by the electrode remain in a large proportion, which may cause corrosion during use. Therefore, in the case of the present invention, rather than connecting each dental metal material to an electrode, a network structure is formed between the dental metal materials using the metal ball, and electrodes are inserted and connected to one or both sides. Dental metal materials can be plated. Also in this case, the contact area between each of the metal balls and the dental metal material may not be plated, but the contact area may be randomly changed by periodically stirring the inside of the plating solution. It can be plated so that unplated parts (voids) are not formed on the entire metal material.

The metal ball may be made of iron, copper, aluminum, nickel, gold, silver, titanium, or an alloy thereof, and preferably, brass having excellent electrical conductivity while having high durability and chemical resistance may be used. In addition, the metal ball preferably has a diameter of 3 to 10 mm. In the case of the metal ball, a network structure may be formed in a kind of random contact with the dental metal material. Therefore, the metal ball preferably has a size similar to that of the dental metal material. At this time, when the metal ball has a size of less than 3 mm, it penetrates into the inside of the dental metal material and it may be difficult to separate it, and when it has a size exceeding 10 mm, the dental metal material settles between the pores of the metal ball. Therefore, it is difficult to make random contact with the dental metal material, so that smooth coating may be difficult. In addition, the number of metal balls may be input 2 to 5 times compared to the number of inputs of the dental metal material. When the metal balls are introduced in an amount less than twice the amount of the dental metal material, contact between the dental metal materials may occur due to an insufficient amount of the metal balls, and accordingly, during plating, the gap between the dental metal materials Adhesion may be formed, and when an amount exceeding 5 times is input, the amount of dental metal material that can be processed at one time is reduced, which is uneconomical.

After connecting the electrode to the rhodium plating solution in which the dental metal material and the metal ball are immersed, plating may be performed for 1 to 20 minutes under a voltage of 0.1 to 30V and a current of 0.1 to 10A.

At this time, the plating conditions may be supplied differently according to the shape of the rhodium plated and formed as described above.

Looking at this in detail, as described above, when acetic acid and sulfuric acid are used and a relatively large amount of hydrofluoric acid is used during etching using the acidic solution, the surface of the dental metal material may have increased roughness and high activation. In this case, when plating is performed for 1 to 8 minutes at a voltage of 1.5 to 2.0V and a current of 0.1 to 0.5A, a uniform rhodium layer can be formed on the surface of the dental metal material. The rhodium layer thus formed prevents the dental metal material from contacting bodily fluids including saliva, thereby preventing corrosion of the dental metal material and reducing inflammation in the oral cavity. At this time, the thickness of the rhodium layer formed is preferably 0.1 to 0.5 μm. When the rhodium layer has a thickness of less than 0.1 μm, durability of the rhodium layer may deteriorate, and when the thickness exceeds 0.5 μm, the amount of rhodium used increases, which is uneconomical.

In addition, separately from this, when nitric acid is used in the etchant and the content of hydrofluoric acid is reduced, the roughness of the surface of the dental metal material may be reduced and the activation degree may be lowered. At this time, when a voltage and current lower than those for forming the rhodium layer are supplied, the rhodium may be aggregated on the surface of the dental metal material to form a kind of microstructure. As described above, the rhodium microstructure formed on the surface of the dental metal material may have hydrophobicity due to the nature of the microstructure, and such a hydrophobic surface may prevent adhesion of body fluids including saliva in the oral cavity. Looking at this in detail, since the liquid in contact with the microstructure formed on the surface of the dental metal material has surface tension, it can be in contact with the microstructure at a certain angle. At this time, if another microstructure adjacent to the microstructure is formed, the liquid may be contacted in a shape connecting the microstructures, and may not descend below a certain portion of the microstructure due to surface tension. . The hydrophobic surface due to this microstructure can be observed on lotus leaves or the skin of reptiles, and in the case of the present invention, rhodium is used to form such a microstructure on the surface of the dental metal material, including Avoid contact with bodily fluids. In addition, the microstructure of the surface of the dental metal material can prevent the reflection of light so that the dental metal material has a matte surface, and can enhance aesthetics and reduce a sense of difference compared to a dental metal material having a glossy surface.

In addition, the rhodium microstructure formed in the present invention may be formed in a spherical shape having a circular, elliptical, or similar shape in cross section of the vertical axis, but by finely adjusting the supplied power, it may be formed in a cylindrical, conical, truncated cone, or polygonal column shape. , it may be manufactured in a non-spherical shape such as a polygonal pyramid shape or a polygonal pyramid shape. In the case of the spherical rhodium microstructure, it is easy to manufacture and uniform production is possible, but if it has a column-shaped, horn-shaped, or horn-shaped microstructure having an angle on the upper surface, hydrophobicity may be increased, so that of the dental metal material Depending on the purpose, it may be appropriately selected and used. In addition, in the case of the column-shaped, horn-shaped, or horn-shaped microstructure, it is possible to form directly on the surface of the dental microstructure, but after forming the spherical microstructure, it is properly processed to form the columnar, horn-shaped, or horn-shaped microstructure. It is also possible to form large-scale microstructures.

In addition, in order to form the microstructure, the plating step may include primary plating for 1 to 10 minutes, preferably 3 to 8 minutes, under conditions of a voltage of 0.1 to 1.5V and a current of 0.1 to 0.3A; and performing secondary plating for 1 to 10 minutes, preferably 2 to 5 minutes, under conditions of a voltage of 1.8 to 30V and a current of 0.4 to 10A.

The primary plating step is a step of forming a microstructure on the surface of the dental metal material, and by forming a plurality of microstructures having an appropriate distance, the surface of the dental metal material can have hydrophobicity. At this time, a microstructure may be normally formed on the surface of the dental metal material within the above condition range, but if it is out of the above range, plating may not be performed or the microstructure may adhere to form a rhodium layer.

The secondary plating is a step of growing the microstructure to an appropriate size by coating the surface of the microstructure formed in the primary plating. When the primary plating is continued, a large amount of microstructures are formed, and as a result, adhesion is formed between the microstructures, so that a rhodium layer other than the microstructures may be formed. Therefore, after a certain amount of the microstructure is generated, it is preferable to grow the rhodium microstructure by adjusting plating conditions. At this time, within the above range, the growth of the microstructure may occur as described above, but outside the above range, the growth of the microstructure may not occur, or parts other than the microstructure may be plated, resulting in poor hydrophobicity.

In addition, the microstructure produced as described above may have a size of 8 nm to 10 μm, preferably 50 to 200 nm. When the microstructure has a size of less than 8 nm, it may be difficult to exhibit hydrophobicity due to the too small size, and when the microstructure has a size exceeding 10 μm, foreign substances may be adsorbed between the microstructures. In addition, the distance between the microstructures may be 10 nm to 10 μm, preferably 100 to 200 nm. When the distance between the microstructures is less than 10 nm, each microstructure may adhere and the surface may be coated with rhodium, and when the distance exceeds 10 μm, hydrophobicity may be deteriorated.

The dental metal material manufactured as described above may be washed and then packaged as a product or combined with other parts to be commercialized. At this time, the washing is performed to remove the plating solution and at the same time to remove the rhodium-precipitated powder, which is immersed in a solution in which distilled water and ethanol are mixed in a weight ratio of 1: 1, and then supplied with ultrasonic waves for 1 to 3 hours. can be performed The ultrasonic waves used at this time are preferably the same as those used in the degreasing and washing steps.

After the washing is completed as described above, the dental metal material may be put into a vacuum oven and then dried at a temperature of 30 to 50 ° C for 5 to 10 hours. At this time, when dried for less than the temperature or for less than 5 hours, water or ethanol may remain on the surface of the dental metal material, and when dried for a temperature exceeding 50 ° C or for a time exceeding 10 hours, the rhodium Delamination may cause defects.

Hereinafter, with reference to the accompanying drawings, a preferred embodiment of the present invention will be described so that those skilled in the art can easily implement it. In addition, in the description of the present invention, if it is determined that a detailed description of a related known function or known configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted. And certain features presented in the drawings are enlarged, reduced, or simplified for ease of explanation, and the drawings and their components are not necessarily drawn to scale. However, those skilled in the art will readily understand these details.

Example 1

After manufacturing 1000 dental metal materials (120 in FIG. 2) as shown in FIG. 2, they were immersed in 500ml ethanol solution and degreased by stirring while supplying ultrasonic waves for 2 hours. After the degreasing was completed, the dental metal material was immersed in 1000 ml of distilled water and washed by stirring while supplying ultrasonic waves for 1 hour.

Etching and activation were performed by immersing the cleaned dental metal material in a solution containing 10 ml of 60 wt% hydrofluoric acid, 10 ml of 40% hydrochloric acid, 10 ml of 20% acetic acid, and 30 ml of 10% sulfuric acid for 5 minutes.

The washed dental metal material was added to 10 L of the plating solution mixed with 1 g/L of rhodium sulfate and 15 ml/L of sulfuric acid, and 3000 brass balls with a diameter of 5 mm were mixed, and then plated at 1.8 volt and 0.25 ampere for 5 minutes.

After the plating was completed, the dental metal material was immersed in a solution in which distilled water and ethanol were mixed in a weight ratio of 1:1, and ultrasonic waves were applied for 2 hours to wash.

After the washing was completed, it was dried in a vacuum oven at 40° C. for 8 hours.

Example 2

After manufacturing 1000 dental metal materials (120 in FIG. 2) as shown in FIG. 2, they were immersed in 500ml ethanol solution and degreased by stirring while supplying ultrasonic waves for 2 hours. After the degreasing was completed, the dental metal material was immersed in 1000 ml of distilled water and washed by stirring while supplying ultrasonic waves for 1 hour.

Etching and activation were performed by immersing the cleaned dental metal material in a mixture of 5 ml of water, 10 ml of 40% hydrochloric acid, and 30 ml of 20% 60% nitric acid for 5 minutes.

Into 10L of the plating solution mixed with 1g/L of rhodium sulfate and 15ml/L of sulfuric acid, the washed dental metal material was added, 3000 brass balls with a diameter of 5mm were mixed, and the first plating was performed at 1 volt and 0.12 ampere for 5 minutes. Then, secondary plating was performed at 2 volts and 0.5 ampere for 3 minutes.

After the plating was completed, the dental metal material was immersed in a solution in which distilled water and ethanol were mixed in a weight ratio of 1:1, and ultrasonic waves were applied for 2 hours to wash.

After the washing was completed, it was dried in a vacuum oven at 40° C. for 8 hours.

Comparative Example 1

In Example 1, instead of the etching and activation process, a physical polishing method was used as in the conventional method.

The physical polishing used at this time used a liquid phase in which 30% by weight of abrasive stone (Keumgangsa) with a grain size of 80 to 90㎛ and 70% by weight of ethyl alcohol were mixed, and the liquid phase was mixed with the dental metal material at a pressure of 5kg/cm2. It was performed by spraying with air for 20 seconds at a distance of 30 cm.

Experimental Example 1

Surfaces and cross sections of the dental metal materials prepared in Examples 1 and 2 and Comparative Example 1 were observed to confirm whether an appropriate rhodium layer was formed.

Figure 3 is a photograph of the surface of Example 1 observed using an optical microscope, Figure 4 is a photograph observed using an SEM, Figure 5 is a cross-sectional photograph observed using a TEM. 3 to 5, in the case of Example 1 of the present invention, it was confirmed that a uniform rhodium layer was formed on the surface of the dental metal material.

6 is a photograph of the surface of Example 2 observed by TEM, and FIG. 7 is a photograph of analyzing the rhodium microstructure. 8 is a photograph confirming the distribution of elements using EDS. As shown in FIG. 6, in the case of the embodiment of the present invention, it was confirmed that the microstructure was formed at an appropriate interval, and as shown in FIG. 7, in the case of the rhodium microstructure of the present invention, a two-layer structure was formed due to two platings. appeared to have Also, as shown in FIG. 8, it was confirmed that this microstructure was composed of rhodium.

9 is an optical micrograph of Comparative Example 1. As shown in FIG. 9, in the case of Comparative Example 1, since the conventional physical polishing method was used, it was confirmed that the surface roughness was significant even after the coating was completed.

Experimental Example 2

Experiments were conducted to confirm defects of the dental metal materials manufactured in Examples 1 and 2. By observing each dental metal material using an optical microscope, micrometer-sized pinholes, voids, and pint defects were selected, and the results are shown in Table 1 below.

Total number of metal materials pinhole (pcs) Boyd (dog) feet (dog) Example 1 1000 5 6 12 Example 2 1000 8 12 9

As shown in Table 1, in the case of the embodiment of the present invention, the defect rate was found to have around 2%. In addition, in the case of Example 2, since nanoscale voids, pinholes, and pits can be formed by the rhodium microstructure, only pinholes, voids, and pits having a micrometer size or larger were judged as defective, and this also resulted in a defect rate of around 2%. appeared to indicate

Experimental Example 3

An experiment was conducted to confirm the dissolution and inflammation inhibitory effect of the dental metal material according to the embodiment of the present invention.

Kimchi, which is frequently consumed by Koreans, generally has an environment of ph 4.5, and to simulate this, a dissolution test of dental metal material (10g) was conducted in a ph 4.5 buffer (500ml) solution for 40 days. As shown in FIG. 10, it was confirmed that only a very small amount of harmful Ni metal within 3 ppm was eluted after 40 days in both Examples 1 and 2 compared to Comparative Example 1.

In addition, after selecting 40 pre-educated participants, the surface of the teeth of Example 1, Example 2, Comparative Example 1 and the existing nickel-plated dental metal material (Comparative Example 2) installed for orthodontic use 20 brackets were installed for each of 10 people (200 each for each Example and Comparative Example). For the next 30 days, they went about their daily lives, but in order to control the conditions as similarly as possible, they ate the same meal at the accommodation and brushed their teeth 3 times a day at the same time. After 30 days, the occurrence of stomatitis in the oral cavity and the number were measured and shown in Table 2 below. In addition, after 30 days had elapsed, the number of dental metal materials deposited with foreign matter (calculus) and the number of corrosion were confirmed and marked.

Occurrence of stomatitis (people) Total stomatitis (dogs) Foreign body deposition (pcs) Example 1 One 3 6 Example 2 2 3 5 Comparative Example 1 5 10 11 Comparative Example 2 10 31 10

As shown in Table 2, in the case of Examples 1 and 2 of the present invention, it was confirmed that stomatitis, foreign matter deposition, etc. were reduced, and corrosion was suppressed, indicating that long-term use was possible. However, in the case of Comparative Example 1 in which physical polishing was performed as in the conventional method, the roughness of the surface increased, resulting in increased deposition of foreign substances and corrosion. It was found that there was a large increase in

Having described specific parts of the present invention in detail above, it will be clear to those skilled in the art that these specific descriptions are only preferred embodiments, and the scope of the present invention is not limited thereby. will be. Accordingly, the substantial scope of the present invention will be defined by the appended claims and their equivalents.

Claims (9)

(a) etching and activating the surface of a dental metal material by immersing it in an acidic solution;
(b) coating rhodium on the surface of the dental metal material after the etching and activation are completed; and
(c) washing and drying the rhodium-coated dental metal material;
Biocompatible coating method of dental metal material comprising a.
According to claim 1,
The acidic solution is hydrofluoric acid (HF), hydrochloric acid (HCl), perchloric acid (HClO ₄ ), chloric acid (HClO ₃ ), hypochlorous acid (HClO), acetic acid (CH ₃ COOH), sulfuric acid (H ₂ SO ₄ ), sulfurous acid ( H ₂ SO ₃ ), nitric acid (HNO ₃ ), nitrous acid (HNO ₂ ), phosphoric acid (H ₃ PO ₄ ), hydrogen iodide (HI), iodic acid (HIO ₃ ), hydrobromic acid (HBr), oxalic acid ( H ₂ C ₂ O ₄ ), arsenic acid (H ₃ AsO ₄ ), chloroacetic acid (CH ₂ ClCOOH), formic acid (HCOOH), benzoic acid (C ₆ H ₅ COOH), hydrazoic acid (HN ₃ ), propionic acid (CH ₃ CH ₂ COOH), Carbonic Acid (H ₂ CO ₃ ), Hydrogen Sulfide (H ₂ S), Hydrocyanic Acid (HCN), Chromic Acid (H ₂ CrO ₄ ), Trifluoromethanesulfonic Acid (CHF ₃ O ₃ S), Methanesul Ponic acid (CH ₃ SO ₃ H), trifluoroacetic acid (CF ₃ COOH), trichloroacetic acid (CCl ₃ COOH), citric acid (C ₆ H ₈ O ₇ ), n-butanesulfonic acid (C ₄ H ₉ SO ₃ H ), camphorsulfonic acid (C ₁₀ H ₁₆ SO ₄ ), tosylic acid, poly(4-styrenesulfonic acid), poly(vinylsulfonic acid), poly(styrene-alt-maleic acid), poly(acrylic acid) and poly(meth) A biocompatible coating method for a dental metal material comprising at least one selected from the group of acrylic acid).
According to claim 2,
The acidic solution,
50 to 60% by weight of hydrofluoric acid 100 parts by weight, 30 to 50% by weight of hydrochloric acid 50 to 1000 parts by weight, 10 to 30% by weight of acetic acid 80 to 120 parts by weight and 5 to 20% by weight of sulfuric acid 280 to 330 parts by weight mixture; or
A mixture of 50 to 1000 parts by weight of 30 to 50% by weight of hydrochloric acid and 50 to 1000 parts by weight of 55 to 70% by weight of nitric acid, based on 100 parts by weight of water;
A biocompatible coating method for phosphorus dental metal materials.
According to claim 2,
The acidic solution is a biocompatible coating method of a dental metal material further comprising a metal salt compound.
According to claim 4,
The metal salt compound is a biocompatible coating of a dental metal material containing at least one member selected from the group consisting of iron chloride, nickel chloride, copper chloride, zinc chloride, manganese chloride, chromium chloride, silver chloride, cobalt chloride, ammonium fluoride, and potassium permanganate. method.
According to claim 1,
In step (b),
preparing a rhodium plating solution by mixing 0.1 to 5 g/L of rhodium sulfate and 1 to 30 ml/L of 90 to 98 vol% sulfuric acid in water;
immersing a dental metal material, which has been etched and activated, into the rhodium plating solution;
Injecting a metal ball into the rhodium plating solution in which the dental metal material is immersed;
Connecting an electrode to the rhodium plating solution in which the dental metal material and the metal ball are immersed, then plating for 1 to 20 minutes under a voltage of 0.1 to 30V and a current of 0.1 to 10A; and
After removing the rhodium plating solution, separating the metal ball and the dental metal material;
Biocompatible coating method of dental metal material comprising a.
According to claim 6,
In the plating step,
Primary plating for 1 to 10 minutes at a voltage of 0.1 to 1.5V and a current of 0.1 to 0.3A; and
Secondary plating for 1 to 10 minutes at a voltage of 1.8 to 30V and a current of 0.4 to 10A;
Biocompatible coating method of dental metal material comprising a.
According to claim 6,
The metal ball,
Made of iron, copper, aluminum, nickel, gold, silver, titanium or their alloys,
It has a diameter of 3 to 10 mm,
A biocompatible coating method for a dental metal material in which 2 to 5 times the number of inputs of the dental metal material is input.
According to claim 1,
The rhodium is
A biocompatible coating method for dental metal materials to form a rhodium layer with a thickness of 0.1 to 0.5 μm or a rhodium microstructure with a size of 8 nm to 10 μm on the surface of the dental metal material.