KR101835623B1 - An electrolyte composition containing magnesium and silicon in a plasma electrolytic oxidation process and a method for manufacturing dental implants coated by hydroxyapatite containing magnesium and silicon ions using the composition - Google Patents

Abstract

The present invention relates to a method for manufacturing implants, which uses an electrolyte solution containing magnesium and silicon to form the surface of a porous oxidation film containing magnesium, silicon ions, calcium and phosphorus on the surface of the dental implants through a plasma electrolytic oxidation method, thereby improving bioactivity, wherein the method comprises the following steps: a titanium alloy preparation step; an input step; a plasma forming step; and a drying step.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrolyte composition containing magnesium and silicon in a plasma electrolytic oxidation process, and a method for producing dental implants coated with apatite hydroxide containing magnesium and silicon ions using the composition. and a method for manufacturing dental implants coated with hydroxyapatite containing magnesium and silicon ions using the composition}

The present invention relates to a method of forming a porous oxide film on a surface of a titanium-based alloy, which is a metal material inserted into a bone in a human body, by using plasma electrolytic oxidation, and more particularly, The surface of the porous oxide film containing magnesium and silicon ions and calcium and phosphorus on the surface of the dental implant was formed by plasma electrolytic oxidation using an electrolyte solution containing magnesium and silicon which plays an important role in cell adhesion and bone formation in the ion A method of manufacturing an implant for improving bioactivity, comprising the steps of: preparing a titanium alloy to sequentially polish, fine-grind and ultrasonically clean a dental titanium alloy; place the titanium alloy prepared in the preparation step on an electrolytic bath anode; After the platinum is installed, the electrolyte solution A plasma forming step of forming an oxide film on a titanium alloy by generating a plasma by applying a constant voltage and a current density to the titanium alloy and forming an oxide film on the titanium alloy in the plasma forming step and drying after drying the ethanol and distilled water An electrolyte composition containing magnesium and silicon in the plasma electrolytic oxidation process, and a method for manufacturing dental implants coated with apatite containing magnesium and silicon ions using the composition.

The most important interest in the field of implant in recent years is shortening of the treatment period, and the most important factor to shorten the treatment period is to keep the osseointegration early. The majority of commercially available implants have high biocompatibility and are believed to have a surface suitable for healing, producing and maintaining bone, but they still can not completely overcome the adverse bone conditions. On the other hand, the titanium-based alloy used as the main material has been reported to be superior to the conventional bio-metals such as low elasticity and excellent biocompatibility and corrosion resistance. However, since it is in vivo inert, it does not directly induce bone formation, takes a long time for treatment to achieve bone connection, and the naturally formed oxide film has a thin thickness, which leads to rapid dissolution and does not lead to regeneration of adjacent bone tissue .

Therefore, in order to solve the above-mentioned problem that the implant can not directly bond with the bone, and to relax the shortening period to shorten the period of bone connection, bioactivity is given through the implant surface treatment. By physically and chemically surface-treating the surface of the titanium used as the main material of the implant, the bioactivity is further improved to shorten the period of healing after the implant is placed in the human body. Studies for more effective surface treatment are continuously carried out In fact. The chemical surface treatment during the titanium surface treatment includes anodizing, sol-gel, plasma spraying, chemical vapor deposition (CVD), and plasma-electrolytic oxidation (PEO-Plasma Electrolytic Oxidation) .

The anodizing method is a method of forming oxide and metal salts relatively thick on a metal surface using an external power source, and a metal to be an oxide layer is formed on the anode and another insoluble metal is brought into contact with the cathode to generate an electric current If an electric current is applied to anodize by flowing, the hydroxide of the metal forms a fine film at a very low voltage, and when a voltage of about 10 V is applied, a metal oxide layer is formed. However, once the oxide layer is formed, resistance is increased, internal stress is concentrated in the metal oxide layer, the oxide layer is destroyed at 70 V, and when the voltage is raised again, a second porous oxide layer is formed. The electric efficiency is poor due to the formation of the oxide layer by applying electricity, and the sparked localized portions are subject to thermal stress, which not only adversely affects the physical properties of titanium, but also adversely affect the final properties.

The sol-gel method is a method of preparing a solution which becomes a gel by hydrolysis and polymerization reaction with alcohol, water and acid in order to prepare a coating film, and a homogeneous solution is prepared in a relatively low viscosity state The wet coating method, such as dip-coating, which applies the sol-gel method by coating on the substrate by gelling on the substrate, is a low-temperature process and can be coated regardless of the area, and the thickness and microstructure of the film can be controlled However, there is a disadvantage in that a post heat treatment process for crystallization is added, formation of a flat plate coating is restricted, and an adhesive for strengthening the adhesion strength is inserted into the intermediate layer so that the coating has a sufficient bonding force with the base material.

Plasma spraying refers to a process in which a material having a high melting point, such as a metal and a non-metallic ceramic material, is deposited on a substrate in a molten state or a semi-molten state. There is no restriction on the material and the size of the base material, it is possible to construct on the spot without causing deformation of the base material, it is possible to form a thick film, easy to control the thickness of the coating, and various kinds of coating materials. Is 0.6 to 15%. It is not a metallic bond, but it has a disadvantage that it is weak against impact when titanium is coated with a ceramic by a mechanical bond, and it is difficult to apply an implant because its bonding with a base material is weak.

The chemical vapor deposition (CVD) method is a method of treating a surface by exposing a gas mixture to a sample at a high temperature, so that various reactions occur to deposit one or more components of the gas mixture in the base material, Method. Is a method commonly used in the field of biomaterials for depositing pyrolytic carbon coatings on substrates such as tantalum, molybdenum, rhenium or graphite.

Plasma electrolytic oxidation is principally the same as anodizing. The anodic oxidation is performed by using a metal (e.g., a sintered steel or a platinum alloy) having a relatively high electrochemical stability with respect to the cathode, The metal to be oxidized, such as magnesium, is placed in the anode. In the plasma electrolytic oxidation process, when a voltage higher than a dielectric breakdown voltage is applied to the pre-formed anodic oxide layer (or dielectric film), a strong current field formed locally in the reacted gas (hydrogen or oxygen gas) An arc (or spark or plasma) is generated. These plasma energy plays a role of fusing momentarily formed oxides, and the surface of the metal located on the anode is formed by a very dense and hard oxide which is completely different from the oxide formed by the anodic oxide film. It is a surface treatment technology applied to a wide range of fields ranging from marine and petrochemical industries. It forms CaO and PO ₄ ions in the electrolyte to form an oxide film that induces the bonding of bone to the metal surface inserted into the bone in the human body By improving the bioactivity, the biocompatibility is improved while being economical. However, problems such as shortening of treatment time due to problems such as failure to bring about regeneration of adjacent bone tissue and disadvantages such as rapid disappearance of oxide film, which are possessed in the prior art, have been partially improved, and still have problems.

Prior art for performing surface treatment of implants by plasma electrolytic oxidation is disclosed in Korean Patent No. 10-1314073 (Oct. 31, 2013), which is a method for manufacturing a titanium implant coated with an oxide film containing calcium triphosphate, and a titanium implant A method for manufacturing a titanium implant for bone implant coated with an oxide film containing calcium phosphate, which is a biocompatible material, comprises the steps of: preparing an electrolyte solution containing phosphate ions; Dispersing the hydroxyapatite particles in the electrolytic solution; And performing a plasma electrolytic oxidation coating on the electrolyte in which the hydroxyapatite particles are dispersed with a titanium implant as an anode. In the course of performing the plasma electrolytic oxidation coating, the phosphoric acid ions of the electrolyte react with hydroxyapatite The method for forming a coating by plasma electrolytic oxidation is a method in which calcium triethoxide formed is contained in an oxide film and a titanium implant is provided. Korean Patent No. 10-1419276 (Apr. 14, 2014) A voltage higher than a voltage applied during a subsequent process is applied at an initial stage of the plasma electrolysis oxidation process and a positive voltage pulse is applied at a voltage applied to the positive electrode and the negative electrode in the plasma electrolytic oxidation chamber, And the ratio of the number of times between the negative voltage pulse The present invention provides a method for forming a coating by plasma electrolytic oxidation applied at a rate of 1: 1 to 2: 1 initially in a zmaic electrolytic oxidation process and at a rate of 30: 1 to 50: 1 after the middle of the process, (A) an electrolytic bath containing phosphoric acid dihydrate potassium (KH ₂ PO ₄ ) and calcium chloride (CaCl ₂ ); and Forming an electrolyte with a mixed aqueous solution; (b) impregnating the electrolytic bath with titanium or titanium for an anode and a metal for a cathode having a reduction potential higher than that of the titanium metal; (c) applying a constant current and voltage to the titanium metal and the cathode metal to generate an arc discharge on the titanium metal to generate a plasma; (d) forming hydroxyapatite (Ca ₁₀ (PO ₄ ) ₆ (OH) ₂ ) on the surface of the titanium metal with ionic materials within the electrolytic cell using the plasma; (e) placing zirconium chloride (ZrCl ₄ ) and titanium metal coated with hydroxyapatite on its surface through the step (d); And (f) heating the inside of the reaction vessel to vaporize the zirconium chloride in a constant gas atmosphere to form a hydroxyapatite / zirconium oxide composite on the surface of the titanium metal.

In the prior art, an oxide film is formed on the surface of a titanium alloy, and an electrolyte solution used in a plasma electrolytic oxidation process includes beta trisphosphate, potassium phosphate dihydrate (KH ₂ PO ₄ ), calcium chloride (CaCl ₂ ) Current density, and the like, thereby forming a porous surface on which an oxide film is formed on the surface of an implant made of a titanium-based alloy, thereby improving bioactivity and inducing bone cell adhesion and bone- Metabolic processes and elements constituting the bones. The elements contained in the electrolyte solution are inadequate in terms of biocompatibility.

Korean Patent No. 10-1314073 (Oct. Korean Patent No. 10-1419276 (Jul. 15, 2014) Korean Patent No. 10-1081687 (2011.11.09.)

The object of the present invention is to increase the initial fixation and reduce the failure rate in the clinic through the provision of an oxide film using ions advantageous to bone formation on the commercially available titanium based bio-alloy, Calcium and phosphorus ions are introduced into the electrolyte by means of plasma electrolytic oxidation, and magnesium and silicon ions, which induce bone-cell adhesion and bone-binding growth among bioactive substance ions, And an electrolyte composition containing magnesium and silicon in a plasma electrolytic oxidation process for providing a composite titanium alloy surface treatment by a plasma oxidation process and a composition thereof, Of dental implants The.

In order to solve the above-mentioned problems and to achieve the object, in the plasma electrolytic oxidation process according to an embodiment of the present invention, the electrolyte composition containing magnesium and silicon is prepared by adding calcium acetate monohydrate, calcium glycerophosphate, , Magnesium acetate tetrahydrate, sodium metasilicate nonahydrate, and distilled water to form an electrolyte solution.

The electrolytic solution was prepared by dissolving 0.12 mol L ^{-1 of} calcium acetate, 0.02 mol L ^{-1 of} calcium glycerophosphate, 0.02 mol L ^-1 of magnesium acetate, 0.03mol L ^-1 and sodium metasilicate electrolytic plasma made of 0.001mol L ^-1 provides a magnesium-containing and silicon oxide in the process electrolyte composition.

 In addition, a method of manufacturing a dental implant having a coating of apatite containing magnesium and silicon ions using the electrolyte composition includes a) preparing a titanium alloy (S10) for sequentially polishing, fine polishing and ultrasonic cleaning a dental titanium alloy, ; b) an inputting step (S20) of installing the titanium alloy prepared in the preparation step on the electrolytic bath anode, the anode being platinum, then the electrolyte solution containing magnesium and silicon being introduced; c) forming a plasma by applying a constant voltage and current density to form an oxide film on the titanium alloy; And d) a drying step (S40) in which an oxide film is formed on the titanium alloy in the plasma forming step, followed by washing with ethanol and distilled water, followed by drying.

The polishing is carried out with a silicon carbide abrasive paper, and is polished stepwise with an abrasive paper having 100, 600, 800, 1200, 2000 grit.

The fine grinding is performed using 0.3 mu m alumina powder, and the alumina powder is removed in the ultrasonic cleaning.

The electrolyte solution is prepared by mixing calcium acetate monohydrate, calcium glycerophosphate, magnesium acetate tetrahydrate, and sodium metasilicate nonahydrate in distilled water.

0.12 mol L ^{-1 of} calcium acetate, 0.02 mol L ^{-1 of} calcium glycerophosphate, and 0.02 mol L ^-1 of magnesium acetate so that the magnesium ion in the electrolyte solution is 20 mol% relative to calcium ion and 5 mol% 0.03 mol L ^-1 and 0.001 mol L ^-1 of sodium metasilicate.

Wherein the voltage, the current density, and the usable time are 250 to 280 V, 50 to 100 mA / cm & lt ^; " ² & gt ^;, and coated for 3 minutes with apatite hydroxide containing magnesium and silicon ions.

As described above, the electrolyte composition containing magnesium and silicon in the plasma electrolytic oxidation process according to the present invention and the method for manufacturing dental implants coated with hydroxyapatite containing magnesium and silicon ions using the composition have the following effects .

(1) According to the present invention, the surface of a dental implant is treated with a titanium-based bio-alloy using a plasma electrolytic oxidation process, thereby simplifying the manufacturing process and reducing the manufacturing time and the duration of the implant.

(2) According to the present invention, a porous oxide film having biocompatibility is produced through a complex substitution of magnesium and silicon ions by a plasma electrolytic oxidation method, and an oxide film thicker and denser than conventional metal oxide films is produced.

(3) The present invention rapidly increases biocompatibility including magnesium and silicon ion bioactive material, thereby reducing the treatment period by increasing the initial fixation force of the dental implant.

1 is a flowchart of a method for manufacturing a dental implant in which apatite hydroxide coated with magnesium and silicon ions is coated by a plasma electrolytic oxidation process according to a preferred embodiment of the present invention.
FIG. 2 is a basic reaction diagram of a plasma electrolytic oxidation surface treatment according to a preferred embodiment of the present invention.
FIG. 3 is an actual view of a surface of a titanium alloy alloy subjected to a plasma electrolytic oxidation treatment in a solution containing magnesium and silicon ions according to a preferred embodiment of the present invention. FIG.
FIG. 4 is a top view of a dental implant subjected to a plasma electrolytic oxidation treatment in a solution containing magnesium and silicon ions according to a preferred embodiment of the present invention.
FIG. 5 is a graph showing energy dispersive X-ray spectroscopy (EDS) of a titanium alloy subjected to plasma electrolytic oxidation according to a preferred embodiment of the present invention.
FIG. 6 is a photograph of an EDS mapping of a titanium alloy subjected to plasma electrolytic oxidation according to a preferred embodiment of the present invention.
FIG. 7 is an X-ray diffractometer (XRD) result graph of a plasma electrolytically oxidized titanium alloy according to a preferred embodiment of the present invention.
FIG. 8 is an apatite real image generated on a surface of a titanium alloy subjected to plasma electrolytic oxidation according to a preferred embodiment of the present invention after immersion in a bioactive solution for 12 hours. FIG.
FIG. 9 is a photograph showing the degree of cell adhesion at the surface of a dental implant alloy subjected to plasma electrolytic oxidation according to a preferred embodiment of the present invention.

The name of the present invention is "an electrolytic composition containing magnesium and silicon in a plasma electrolytic oxidation process and a method for manufacturing dental implants coated with apatite hydroxide containing magnesium and silicon ions using the composition," And the detailed description that can sufficiently be inferred is omitted and, if necessary, examples and drawings are described. In addition, terms defined in the present specification and claims are not to be interpreted as limiting, and may be changed according to the intention or custom of the operator, and should be construed in a meaning and a concept consistent with the technical idea of the present invention.

In one aspect of the present invention,

FIG. 1 is a flow chart of a method for manufacturing a dental implant in which apatite hydroxide coated with magnesium and silicon ions is coated by a plasma electrolytic oxidation process according to a preferred embodiment of the present invention. FIG. 2 is a cross- Fig. 1 is a schematic diagram of a plasma electrolytic oxidation surface treatment according to a first embodiment of the present invention. Fig.

In the electrolytic composition of the plasma electrolytic oxidation process,

The electrolyte composition comprises

The electrolyte solution is composed of calcium acetate monohydrate, calcium glycerophosphate, magnesium acetate tetrahydrate, sodium metasilicate nonahydrate, and distilled water.

The electrolytic solution was prepared by dissolving 0.12 mol L ^{-1 of} calcium acetate, 0.02 mol L ^{-1 of} calcium glycerophosphate, 0.02 mol L ^-1 of magnesium acetate, 0.03 mol L ^-1 and 0.001 mol L ^-1 of sodium metasilicate.

A method of manufacturing a dental implant comprising a titanium alloy,

The dental implant manufacturing method includes:

a) preparing a titanium alloy (S10) for sequentially polishing, fine polishing and ultrasonic cleaning the dental titanium alloy;

b) an inputting step (S20) of installing the titanium alloy prepared in the preparation step on the electrolytic bath anode, the anode being platinum, then the electrolyte solution containing magnesium and silicon being introduced;

c) forming a plasma by applying a constant voltage and current density to form an oxide film on the titanium alloy; And

d) forming an oxide film on the titanium alloy in the plasma forming step, followed by washing with ethanol and distilled water, followed by drying (S40).

Ti-6Al-4V and Ti-6Al-4V extra low interstitial (ELI) are widely used as the commonly used titanium, and titanium is an element constituting the crust and oxygen, silicon, aluminum, , Is the ninth most abundant element following sodium, potassium, and magnesium. Its density is 4.5 g / ㎤ which is 40% lighter than stainless steel (7.95 g / ㎤) and relatively low specific gravity. And the microstructure is composed of only HCP (alpha phase). The diameter of the crystal grains becomes 10 ~ 150 mu m according to the effect of cold working, and the material is strengthened by forming an interstitial solid solution.

The Ti-6Al-4V alloy is mixed with HCP (alpha phase) and BCC (beta phase), and the microstructure is largely affected by the heat effect and is also affected by the processing process. When the temperature is maintained at the above temperature, the α phase of the needle and plate is precipitated in a specific direction in the crystal of β, and this is called "Widmanstten" structure. When the β phase is quenched, martensite is formed. The ordinary Ti-6Al-4V is processed by heating at a temperature of about 882 ° C, which is the transformation temperature of the β phase. Annealing is performed to precipitate β-phase grains on a fine α phase matrix and grain boundaries. And low thermal conductivity and electrical conductivity, and α-Ti is transformed into β-Ti at a temperature of 882 ° C. However, high-temperature β-Ti can not bring the β-phase to room temperature by quenching, and it becomes an acicular α-Ti structure.

Titanium is currently the most widely used implant material because of its excellent mechanical properties and biocompatibility. Titanium is highly reactive and oxidizes when contacted with air or body fluids. This oxidation reaction increases the resistance of the corrosion reaction in the body, And it is preferable to use Ti-6Al-4V as the material of the titanium alloy of the present invention.

In the plasma electrolytic anodization process according to the present invention, a dense oxide film is initially formed on the surface of the metal, and a barrier layer is formed over time, and the porous surface layer is generated in proportion to the applied voltage and continues to grow. When the generation and destruction of the oxide film are repeatedly performed by the plasma discharge after the formation, localized high temperature heat is generated to cause a dissolving action on the surface. Such repetition of the reaction is stopped when the applied voltage stops and the surface roughness is increased, And the main reaction occurring in the anode during the plasma electrolytic oxidation process is as follows.

First, the reaction at the Ti / Ti oxide interface

Ti - > Ti < ^{2 +} & ^{gt ;} + 4e ^-

Second, it can be divided into two reactions at the Ti oxide / electrolyte interface. Oxygen ions react with Ti to form oxides, and an oxygen gas reaction formed on the electrode surface appears.

2H ₂ O → 2O ^{2 -} + 4H ⁺

2H ₂ O? O ₂ (gas) + 4H ⁺ + 4e ^-

Third, the final reaction

Ti ^{2 +} + 2O ^{2 -} > TiO ₂ + 2e ^-

When a voltage is applied to an aqueous solution containing an electrolyte in an electrolytic bath, oxygen gas is generated at the surface of the anode, oxidation reaction of the metal occurs, hydrogen gas is generated at the cathode, or reduction reaction occurs.

Magnesium is one of the major substituents of calcium and is the fourth most abundant cation in the extracellular matrix of bone, contained in enamel, dentine, and bone. Therefore, magnesium deficiency affects bone mineral density and bone ductility by reducing bone metabolism and osteocyte growth. More specifically, it is believed that magnesium-deficient bone marrow cells such as Sr-strontium, Mg-magnesium, Zn-zinc, Na-sodium, Si-silicon, silver-silver, and yttrium play an important role in bone formation because they affect bone density. It is known. In particular, recently, the preparation of magnesium-substituted apatite phase and the formation and growth of crystals in HA have been studied, and magnesium has been known as a calcium substitute because it has a structure in which cationic lattice structure of HA can be easily substituted with various elements, Ca ₁₀ - _x Mg _x (PO ₄ ) ₆ (OH) ₂ . (Mg ^{2 +} , Zn ^{2 +} , Sr ^{2 +} ) and anions (SiO ₄ ^{4 -} , F ^- , CO ² , and Fe ² O ₃ ) as the substituents, ₃ ^2- ) is mainly used. Magnesium is one of the major substituents of calcium and contains 0.2 wt.%, 1.1 wt.% And 0.6 wt.% Of enamel, dentine and bone, respectively. Is the fourth most abundant cation in the. Magnesium deficiency is associated with a decrease in the bone mineral density and bone mineral density of the osteoblasts and osteoblasts, thereby increasing the probability of fracture, and calcium deficiency HA [d-HA, Ca _{10 - x} (HPO _{4) x (PO 4) 6} -x (OH) 2-x; 0 = x = 1] Substituting magnesium in the lattice makes Mg-HA more biocompatible and comparable to hard tissue. Therefore, magnesium has a good effect as a bioactive material by controlling physicochemical properties and controlling biocompatibility and biological activity as a result of solubility, crystallinity, particle shape, and nanoparticle synthesis, and silicon is also involved in the new metabolism, And is effective as a bioactive material in the same manner as magnesium.

The polishing is carried out with a silicon carbide abrasive paper, and is polished stepwise with an abrasive paper having 100, 600, 800, 1200, 2000 grit.

The fine polishing is performed using 0.3 mu m alumina powder. Ultrasonic cleaning is performed in ethyl alcohol for 10 minutes to remove the alumina powder. In this step, the electrolyte solution is applied before the positive electrode is installed, It is preferable to stir the mixture at 200 rpm and to dispose the anode and the cathode at a distance of 20 to 40 mm.

The electrolyte solution is prepared by mixing calcium acetate monohydrate, calcium glycerophosphate, magnesium acetate tetrahydrate, and sodium metasilicate nonahydrate in distilled water.

0.12 mol L ^{-1 of} calcium acetate, 0.02 mol L ^{-1 of} calcium glycerophosphate, and 0.02 mol L ^-1 of magnesium acetate so that the magnesium ion in the electrolyte solution is 20 mol% relative to calcium ion and 5 mol% 0.03 mol L ^-1 and 0.001 mol L ^-1 of sodium metasilicate.

The voltage, the current density and the usable time were 250 to 280 V, 50 to 100 mA / cm ^-2 and 3 minutes, and a separate cooling system was installed to maintain the internal temperature of the electrolytic bath at 25 ° C. It is preferable to dry it after forming an oxide film and then using warm air.

Example  : plasma  Magnesium and silicon ions are removed by the electrolytic oxidation process contain Manufacture of Dental Implants Coated with Hydroxyapatite

Ti-6Al-4V disc (grade 5, Timet Co., Ltd., japan diameter: 10 mm, thickness: 3 mm) was used as the abrasive for silicon carbide abrasive paper and graded to 100, 600, 800, Polishing and micro-polishing with aluminum oxide (Al ₂ O ₃ ) having a particle size of 0.3 μm, and then ultrasonic cleaning was carried out. Then, magnesium ions in the electrolytic solution (distilled water 1 L) were adjusted to 5, 10 and 20 mol% (Calcium acetate monohydrate), calcium glycerophosphate, magnesium acetate tetrahydrate and sodium metasilicate (as shown in the following Table 1) so that the amount of silicon ions is 5 mol% Sodium metasilicate nonahydrate) was weighed and placed in a sterilized sterilized beaker in the third distilled water of the ultrapure water production apparatus. The above reagent was put in a stirrer and stirred at 200 rpm for 30 minutes or more using a magnetic bar. It was prepared such that a solution. The electrolytic solution is manufactured and filled in the electrolyzer, the installation of the specimens finished the ultrasonic cleaning of the anode, cathode electrolytic plasma after installing platinum by applying 280V, 70mA / ㎝ ^-2 3 minutes and subjected to oxidation treatment Respectively.

Furthermore, the dental implants made of the same material of titanium alloy were subjected to the oxidation treatment under the same conditions as those of the specimens subjected to the plasma electrolytic oxidation in the above example.

Test Example  1: Ca (Mg) / P ( Si ) Mol%  Surface porosity of specimen according to the ratio

In the above example, the surfaces of the specimens subjected to plasma electrolytic oxidation and the surfaces of the dental implants were measured by an electron microscope, and magnesium ions were 5, 10, and 20 mol%, respectively, compared to calcium ions and 5 mol% The pore state of the treated surface was examined.

FIG. 3 is an actual view of a surface of a titanium alloy alloy subjected to a plasma electrolytic oxidation treatment in a solution containing magnesium and silicon ions according to a preferred embodiment of the present invention. FIG. 4 is a cross- The surface of the dental implant subjected to the plasma electrolytic oxidation treatment in the solution containing the surfactant will be described in detail with reference to FIG. 3 to FIG.

FIG. 3 is a graph showing the surface of a specimen subjected to plasma electrolytic oxidation in a solution containing magnesium and silicon ions, in which the pores having a size of micrometer unit are uniformly distributed on the oxide film surface of magnesium and silicon ions, , And showed smaller pore shape with increasing concentration of magnesium. Therefore, it was found that as the concentration of magnesium ion (20Mg / 5Si) was increased, a lot of small pores were formed, and thus, it was found that it was favorable for bone joining.

FIG. 4 is a graph showing the results obtained by measuring the surface of a dental implant having the highest magnesium ion (20Mg / 5Si) in an embodiment by forming a uniform pore shape as shown in FIG. 3, .

Test Example  2: plasma  EDS and EDS mapping of electrolytically oxidized titanium alloy specimens

Energy Dispersive X-ray Spectroscopy (EDS) is used as an additional equipment to the scanning electron microscope equipment. It collects the specific X-rays of the sample generated by the electron beam of the scanning electron microscope and analyzes the components. More specifically, when an electron beam is applied to a sample (a titanium-based alloy specimen subjected to a plasma electrolytic oxidation treatment in the embodiment), electrons in the atom absorb energy to become excited, and the excited electrons are stabilized again, Since the emitted X-rays have a unique energy value for each substance, X-rays are collected using a detector, and the collected X-rays are classified according to intensity to perform qualitative analysis on the samples.

FIG. 5 is a graph showing energy dispersive X-ray spectroscopy (EDS) results of a titanium alloy subjected to plasma electrolytic oxidation according to a preferred embodiment of the present invention, and FIG. 6 is a graph showing the results of plasma- Titanium alloy EDS mapping actual view will be described in more detail below with reference to FIG. 5 to FIG.

FIG. 5 shows that the components used in the electrolytic solution were uniformly distributed as a result of the EDS analysis of components of calcium, magnesium, phosphorus, and silicon ions on the surface of the titanium alloy oxide film. FIG. The distribution of calcium, magnesium, phosphorus, and silicon ions on the surface of the titanium alloy was observed by EDS mapping. As a result, it was confirmed that the titanium alloy was evenly distributed over the entire surface of the titanium alloy through the plasma electrolysis process.

Test Example  3: plasma  Electrolytic Oxidized Titanium Alloy Specimens XRD

The X-ray diffractometer (XRD) measures the intensity of a diffracted ray by measuring the intensity of a diffracted ray by changing the diffraction angle of a monochromatic X-ray by a single crystal or a powder sample by X-ray circulation, It is also called diffractometer. It uses X-ray tube, which is an inclusion tube with a stable power source, and combines soller slits, etc., to produce a beam having a proper opening angle. In the case of a powder sample, a goniometer (angle measuring instrument) that interlocks the sample with a counter tube rotates a molded plate-shaped object at an angular velocity ω, rotates the counter tube at 2ω, Collect the excitation line just before the counter. The counter is usually a Geiger-Müller counter. When precision is required, the proportional counter or scintillation counter is used in combination with the analyzer. In addition to the linear diffractometer, there is also a four-axis diffractometer which is made exclusively for a single crystal, which is controlled by a computer, processes the measurement result, makes a determination, and moves to the next measurement.

FIG. 7 is a graph showing the distribution of calcium, magnesium, phosphorus, and silicon ions on the surface of a titanium alloy specimen as a result of X-ray diffraction (XRD) of a titanium alloy subjected to plasma electrolytic oxidation according to a preferred embodiment of the present invention 6 showed that the apatite phase and the anatase phase could be obtained. As the concentration of magnesium ion increased, the apatite phase shifted to the left, which is considered to have affected the apatite phase.

Test Example  4: plasma  Electrolytically oxidized titanium alloy was added to the bio-similar solution Immersed  Apatite generated on the posterior surface

FIG. 8 is a graph showing the relationship between the thickness of the titanium alloy sample and the thickness of a simulated body (hereinafter, referred to as " SBF ") of the titanium alloy sample prepared in Example 1 by immersing the titanium alloy subjected to the plasma electrolytic oxidation treatment according to a preferred embodiment of the present invention in a bio- fluid was prepared by immersing in apatite.

The biocompatible solution contained Na ⁺ (142.0 mM), K ⁺ (5.0 mM), Ca ²⁺ (2.5 mM), Cl ^- (103.0 mM), HCO ^{3 -} (10.0 mM), HPO ^{4 -} (1.0 mM) and SO ₄ ^2- (0.5 mM) were prepared and placed in a beaker in 200 ml increments. The samples were maintained at 36.5 ° C ± 1 ° C, pH 7.4, similar to the oral environment in an incubator, And observed after immersion.

As shown in FIG. 8, after observation for 12 hours, it was found that apatite was formed on the surface of magnesium oxide and silicon ion in the oxide film formed on the surface of the titanium alloy within a short time.

Test Example  5: plasma  Electrolytic oxidation-treated dental implants Iron  Surface cell Degree of attachment

FIG. 9 is a photograph showing the degree of adhesion of cells on the surface of a dental implant alloy treated with plasma electrolytic oxidation according to a preferred embodiment of the present invention. Referring to FIG. 9, cells are human kidney cells 293 (kidney cells 293) Calcium, phosphorus, magnesium and silicon ions were incubated for 24 hours on the surface of a titanium alloy (an example) having an oxide film formed by an electrolytic oxidation process. The results were the same as those obtained when evaluation of apatite formation was observed using a scanning electron microscope And the degree of cell growth and adhesion.

In a further aspect,

Silver nanoparticles may be added to the electrolyte solution to add silver ions to impart antimicrobial properties to the oxide film. The implant implants may have bacterial infections, which may result in periarticular inflammation in the implanted tissue, which is characterized by osseointegration loss at the site of osseointegration in the implanted implant and is known to be caused by excessive occlusal force or infection have. Implants can be divided into peri-implant mucositis and peri-implantitis, and peri-implantitis is characterized by edema, redness, and hemorrhage. peri-implntitis has a wider range of inflammatory symptoms, with loss of crater-like bone along with pyrogen.

On the other hand, if we look at the antimicrobial mechanism of silver ions due to the addition of silver nanoparticles, the cell membrane is composed of a bilayer of phospholipids. Since oxygen bonded to the phospholipids contains anions, the cell membrane has a characteristic of negative charge as a whole, The silver ions reach the cell membrane by diffusion, adsorbing to the cell membrane and destroying the cell structure. Silver ions adsorbed to proteins such as cell membranes and enzymes bind to the sulfhydryl group (-SH) of cysteine, a protein-forming amino acid, to convert it to sulfide and cause energy metabolism disorders by modification of protein enzymes. In addition, silver ions are directly ingested in microorganisms, and they bind with DNA, RNA, celluara protein, and resporatory enzyme to interfere with movement, growth and division, or cause metabolic disturbances in the cytoplasm of bacteria and inactivate them. It destroys cell walls or adsorbs silver ions on the cell membrane, causing the phospholipids of the cytoplasmic anions to migrate to one side, resulting in inactivation of microorganisms by loss of DNA replication ability.

By adding 0.03 mol L ^-1 of silver nanoparticles to the electrolyte solution, the titanium alloy is plasma electrolytically oxidized to have antimicrobial activity on the surface, and the effect of osseointegration is enhanced by magnesium and silicon ions.

Further, in the present invention, the plasma electrolytic oxidation process is performed using the positive electrode or the three electrode using the DC voltage, but an AC voltage may be used. In this case, the AC voltage may use an asymmetrically pulsed voltage, Applying an asymmetric pulsed voltage can cause the positive portion of the pulse to form the converted surface and the oxide layer is formed and the surface converted at the initial stage of the layer growth process has a dense structure and the thickness of the oxide layer coating is The thickness of the oxide film can be increased by performing the plasma oxidation process multiple times by changing the ratio of the current density given to the anode and the cathode, and increasing the porosity of the coating by increasing the porosity of the coating.

In addition, the attachment of osteoblasts to the implants depends on the surface characteristics of the implants. Chemical composition, surface energy, and surface morphology have an important influence on maturation as well as osteoblast attachment, The increase promotes early cell adhesion and expansion, thereby inducing a wider range of bone formation. In general, differences in surface chemical composition and surface energy may be due to differences in hydrophilicity, which acts as a moderate factor for early osteoblast attachment and differentiation. Accordingly, in order to increase the biocompatibility of the surface of the implant, ultraviolet rays, UV-ozone may be treated on the surface of the titanium alloy of the present invention which has been subjected to the plasma electrolytic oxidation treatment, or a step of irradiating a laser to add hydrophilicity to the surface of the implant have.

In order to treat ultraviolet rays and ultraviolet ray-ozone, an oxide film is formed after the plasma electrolytic oxidation process in the present invention, and ultraviolet rays or ultraviolet ray-ozone is applied to the surface of the titanium alloy after the drying step is finished, and the surface is treated for 5 minutes to hydrophilize the surface of the titanium alloy Or Er-Cr.YSGG laser, which is widely used recently, is used to increase the biocompatibility by using CO ₂ laser or Er-Cr.YSGG laser after completion of the drying step as above, It is preferable to set the energy to 100 to 120 mJ and the 20 Hz frequency for 2 minutes at the distance.

As described above, an oxide film containing magnesium and silicon ions is formed on the surface of a titanium alloy dental implant by plasma electrolytic oxidation, and nanostructure porosity is imparted to provide a nanostructure with a large surface area, thereby being more advantageously applied to osseointegration, Is used as a pathway for transferring various chemical substances, drugs, and biomolecules that reach the protein level, and acts only in a specific region. Therefore, the porous space exhibits a great effect as a small-capacity drug, Side effects can be reduced.

In addition, the surface of the dental implant is treated with a titanium-based bio-alloy by a plasma electrolytic oxidation process, so that the manufacturing process is simple, and the implant preparation time and treatment period are reduced, and the plasma electrolytic oxidation method The porous oxide film having a biocompatibility was produced. The oxide film was thicker and denser than the conventional metal coral film and the biocompatibility including the magnesium and silicon ion bioactive material was rapidly increased. Thus, the initial fixation force of the dental implant Increase the treatment period.

While the present invention has been described in connection with certain exemplary embodiments and drawings, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, Various modifications and variations are possible.

Claims (8)

In the electrolytic composition of the plasma electrolytic oxidation process,
The electrolyte composition comprises
An electrolyte solution including calcium acetate monohydrate, calcium glycerophosphate, magnesium acetate tetrahydrate, sodium metasilicate nonahydrate, and distilled water,
The electrolytic solution was prepared by dissolving 0.12 mol L ^{-1 of} calcium acetate, 0.02 mol L ^{-1 of} calcium glycerophosphate, 0.02 mol L ^-1 of magnesium acetate, 0.03 mol L ^-1 and 0.001 mol L ^-1 of sodium metasilicate,
Wherein 0.03 mol L ^-1 of silver nanoparticles is further added to the electrolyte solution, wherein magnesium and silicon are contained in the electrolytic solution. delete A method of manufacturing a dental implant comprising a titanium alloy,
The dental implant manufacturing method includes:
a) a titanium alloy preparation step in which a dental titanium alloy is sequentially polished, micro-polished and ultrasonically cleaned;
b) an input step in which the titanium alloy prepared in the preparing step is installed in an electrolytic bath anode, the anode is platinum, and then an electrolyte solution containing magnesium and silicon is introduced;
c) forming a plasma by applying a constant voltage and current density to form an oxide film on the titanium alloy; And
d) forming an oxide film on the titanium alloy in the plasma forming step, followed by washing with ethanol and distilled water, followed by drying; and
The electrolyte solution is prepared by mixing calcium acetate monohydrate, calcium glycerophosphate, magnesium acetate tetrahydrate and sodium metasilicate nonahydrate in distilled water,
The electrolyte solution is a magnesium ions compared to 20 mol%, the silicon ions in preparation for the ion of calcium acetate to be 5 mol% 0.12 mol L ^-1, calcium phosphate glycerophosphate is 0.02mol L ^-1, magnesium acetate, calcium ions 0.03 mol L ^-1 and 0.001 mol L ^-1 of sodium metasilicate,
0.03 mol L ^-1 of silver nanoparticles was further added to the electrolyte solution,
The plasma forming step may be performed using an anode or three electrodes using a DC voltage. Alternatively, the AC voltage may be replaced with an asymmetric pulsed voltage,
Wherein the surface of the titanium alloy after the drying step is irradiated with ultraviolet ray-ozone for 5 minutes to hydrophilize the surface of the titanium alloy. The method of claim 3,
Wherein the polishing is performed with a silicon carbide abrasive paper and polished stepwise with an abrasive paper having 100, 600, 800, 1200, and 2000 grit, wherein the apatite is coated with magnesium and silicon ions. The method of claim 3,
Wherein the micro polishing is performed using 0.3 탆 alumina powder and the alumina powder is removed while ultrasonic cleaning is performed. delete delete The method of claim 3,
Wherein the voltage and the current density are 250V, 50-100 mA / cm <" ² & gt ^;, and the dissolution time is 3 minutes. The method according to claim 1, wherein the hydroxyapatite-coated magnesium and silicon ions are coated.

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