KR20150131863A

KR20150131863A - implant forming hydroxyapatite coating layer using RF magnetron sputtering and manufacturing method thereof

Info

Publication number: KR20150131863A
Application number: KR1020140059246A
Authority: KR
Inventors: 정운조
Original assignee: (주)오티앤티
Priority date: 2014-05-16
Filing date: 2014-05-16
Publication date: 2015-11-25

Abstract

The present invention relates to an implant and a method of manufacturing the same, and more particularly, to a dental implant and an orthopedic implant using a RF magnetron sputtering method having a high adhesive force and a large area coating effect, And a method for manufacturing the same.
The implant having the apatite hydroxide coating formed by RF magnetron sputtering according to the present invention has a ceramic or metal base material and a coating film formed on the surface of the base material by RF magnetron sputtering and containing apatite hydroxide .

Description

TECHNICAL FIELD [0001] The present invention relates to an implant having a hydroxyapatite coating layer formed by RF magnetron sputtering and a method of manufacturing the same,

The present invention relates to an implant and a method of manufacturing the same, and more particularly, to a dental implant and an orthopedic implant using a RF magnetron sputtering method having a high adhesive force and a large area coating effect, And a method for manufacturing the same.

Currently, the materials used in dental and orthopedic implants are pure titanium (Ti) or titanium alloys (Ti-6Al-4V), and titanium has excellent biocompatibility, so titanium implants have a high clinical success rate. However, since titanium has no bioactivity, the bone formation reaction is slow and the healing period is long, and the adhesion between the bone and the implant is weak.

In order to solve this problem, studies have been carried out to improve the bone-bonding ability by physically or chemically treating the surface of the implant or by preparing it as a porous body to increase the surface area and to change the surface composition and shape. However, have.

(Hydroxyapatite, Ca ₁₀ (PO ₄ ) ₆ (OH) ₂ , HA) with bioactivity on the titanium surface as a method for accelerating the bone formation reaction and shortening the healing period and increasing the adhesion of bone and implant interface. Have been actively researched and developed.

Among them, there is a nano-structured HA coating method (J. Biomed. Mater. Res., 59, 312-317, 2002) in which yttrium (Y) is doped in HA to enhance the osseointegration strength. Another method is to impregnate collagen fibers with nano-sized HA crystals (Biomedical Engineering Handbook, pp. 274, 1995).

Another method (plasma spraying method) in which HA crystals are coated by melt spraying using plasma is also used (International Thermal Spray Conference, 28-30 May, 2001, Singarpore pp. 105).

However, the plasma spray method and the anodizing method are exposed to some problems such as weak adhesion of the HA coating layer to the metal and degradation or absorption of the HA coating layer in the human body, and the failure rate And it has not been commercialized in earnest. In addition, the most important point of the implant treatment is shortening of the bonding time to the bone and strong adhesion at the interface is required. HA coated with the plasma spraying or anodic oxidation method is the cause of the failure of the implant due to the peeling phenomenon at the interface with titanium .

The present invention has been made to overcome the above problems, and it is an object of the present invention to provide a method for producing a bioactive apatite having high bioactivity by using an RF magnetron sputtering method capable of achieving excellent adhesion to a substrate among various PVD coating techniques, And to provide a method of manufacturing the implant having excellent characteristics of a coating film by coating the implant on the surface of an orthopedic implant.

In order to accomplish the above object, an implant having an apatite hydroxide film formed by RF magnetron sputtering according to the present invention comprises a base material of a ceramic or metal material; And a coating film formed on the surface of the substrate by RF magnetron sputtering and containing apatite hydroxide.

The HA coating film is further characterized by containing β-TCP tricalcium phosphate (β-TCP).

And a buffer layer formed of titanium or titanium nitride between the substrate and the coating film.

In order to accomplish the above object, there is provided a method of manufacturing an implant having a hydroxyapatite coating film using RF magnetron sputtering, the method comprising: a target manufacturing step of manufacturing a target containing apatite hydroxide; And a coating step of forming a coating film on the surface of the ceramic or metal substrate by RF magnetron sputtering after the target is installed in the chamber.

The target is a mixed powder obtained by mixing 50 to 60% by weight of the hydroxyapatite, 35 to 45% by weight of tricalcium phosphate (β-TCP), 1 to 5% by weight of at least one additive selected from calcium oxide and phosphorus pentoxide And then sintering it.

In the coating step, the pressure of the chamber is maintained at 5 to 30 mTorr by injecting argon gas, and then sputtering is performed at a power of 100 to 500 W for 1 to 5 hours to form the coating layer with a thickness of 0.1 to 2 탆.

As described above, according to the present invention, an apatite hydroxide coating having high bioactivity is formed on the surface of a base material by using an RF magnetron sputtering method capable of achieving excellent adhesion to a base material and facilitating large-area coating, The physical properties of the coating film are excellent.

The implant of the present invention can be usefully used for dental, orthopedic, and plastic surgery implants.

1 is a coating film formed with an RF power of 130 W,
2 is a coating film formed with an RF power of 160 W,
3 is a coating film formed with an RF power of 190 W,
4 is a coating film formed with an RF power of 220 W,
5 is a coating film formed with an RF power of 250 W,
6 to 7 are graphs showing scratch test results of a coating film formed with an RF power of 200 W. FIG.

Hereinafter, an implant having a hydroxyapatite coating film formed by RF magnetron sputtering according to a preferred embodiment of the present invention and a method for manufacturing the same will be described in detail.

An implant having an apatite hydroxide film according to an embodiment of the present invention includes a base material and a coating film formed on the surface of the base material.

Various components of dental or orthopedic and plastic surgery implants can be used. Examples of components of a dental implant include crown, abutment, screw, fixture, and the like. In addition to dental implants, brackets and wires, which are dental prosthetic components, can be used as the base material.

Metal or ceramic is applied to the base material. The metallic material may be made of a single metal such as titanium (Ti), zirconium (Zr), or aluminum (Al), or may be made of an alloy in which two or more metal components are mixed. Further, a sintered body obtained by sintering zirconia, alumina oxide or the like with a ceramic material can be used.

The coating film is formed on the surface of the substrate by an RF magnetron sputtering method. For example, the coating film may be formed to a thickness of 0.1 to 2 mu m.

The RF magnetron sputtering method is an eco-friendly process that does not emit pollutant emissions, and enables precise process control and excellent adhesion and abrasion resistance of the coating film. RF magnetron sputtering is easy to coat regardless of whether the target material is an insulator such as ceramics or a conductor such as a metal. The accelerated ions in the argon gas plasma strongly collide with the target surface, and the protruding target material reaches the surface of the substrate with high kinetic energy and has strong physical bonding with the coating material.

When using a target containing hydroxyapatite, apatite hydroxide as a target material is coated on the surface of the substrate by strong physical bonding with the substrate. Therefore, the coating film has a high adhesive force with the substrate and also has excellent physical properties of the film.

A sintered body obtained by sintering apatite hydroxide powder as a target to form a coating film containing apatite hydroxide can be used.

Hydroxyapatite (HA) (Ca ₁₀ (PO ₄ ) ₆ (OH) ₂ ), one of the bioactive ceramics, has the same physical and chemical properties as calcium, phosphorus and constituent elements that make up the bones of our body. It is most similar and has strong chemical bonding with internal body tissues, so it has excellent bioactivity and natural bonding is possible.

In addition, other components besides the hydroxide apatite can be further contained in the coating film. For this purpose, a target to which other ingredients are added besides apatite hydroxide can be used. For example, the target may further contain β-TCP tricalcium phosphate (β-TCP). For example, a sintered product obtained by sintering a mixed powder obtained by mixing 50 to 60% by weight of apatite hydroxide and 40 to 50% by weight of tricalcium β-TCP (β-TCP) can be used. β-Tricalcium Phosphate has the advantage of enhancing the bone adhesion and bone regeneration ability of the implant without reducing the strength of the coating film.

Tricalcium phosphate (TCP) (Ca ₃ (PO ₄ ) ₂ ) has a homology between β-phase (α-TCP) and α-phase (α-TCP). The β phase has a hexagonal crystal phase at a low temperature, and when the β phase is thermally treated at 1100-1180 ° C., it transforms into a phase α phase having a monoclinic phase. This high-temperature α-phase reacts violently with water and is therefore unsuitable for use as a biomaterial. In addition, the? -Phase has a higher density than the? -Phase having a lower density, so that the strength of the coating film is not lowered.

The coating film formed on the surface of the substrate using a target containing apatite hydroxide and tris (3-calcium phosphate) has high bone adhesion and bone regeneration ability of the implant.

In another embodiment of the present invention, a buffer layer may be further formed between the substrate and the coating film. For example, a buffer layer is formed on the surface of the substrate, and a coating film containing apatite hydroxide is formed on the surface of the perforated layer.

The buffer layer is made of titanium (Ti) or titanium nitride (TiN). The buffer layer can be formed on the surface of the substrate by a RF magnetron sputtering method using a titanium target or a titanium nitride target. The buffer layer formed between the base material and the coating film improves the bonding strength of the coating film to further enhance the properties of the coating film.

Hereinafter, a method for producing an implant having the above-described apatite hydroxide coating film will be described.

A method of manufacturing an implant having an apatite hydroxide film according to an embodiment of the present invention includes a target manufacturing step of manufacturing a target containing apatite hydroxide and a coating step of forming a coating film on the surface of the substrate.

Each step will be examined in detail.

1. Target manufacturing stage

First, a target to be used for RF magnetron sputtering is manufactured.

As an example of the target, a sintered body obtained by sintering apatite hydroxide powder can be used. In order to form a coating film having chemical uniformity, it is necessary to secure a target of good quality.

To prepare the target, apatite hydroxide powder is prepared. Hydrophilic apatite can be synthesized by a wet synthesis method, a dry synthesis method, a hydrothermal synthesis method, etc. Among these, apatite hydroxide powder having a mole ratio of Ca to P of 1.67 can be prepared by a precipitation method in a wet synthesis method. It is of course possible to purchase and use a commercialized product.

The hydroxyapatite powder can be manufactured into a sintered body by using a sintering method. As the sintering method, a pressure sintering method or a spark plasma sintering (SPS) method can be used.

For example, a pressure sintering method is used. In this case, pressure sintering is performed under temperature and pressure conditions to induce densification of density. For example, the apatite hydroxide powder is placed in a carbon mold of a pressure sintering furnace, and pressed and sintered in an Ar gas atmosphere at a temperature of 950 to 1100 ° C for 30 minutes while applying a pressure of 25 to 35 MPa to produce a sintered body. The sintered body thus prepared is used as a target.

Discharge plasma sintering is a sintering method which can remarkably reduce sintering time until powder is densified compared to conventional hot pressing methods and hot isostatic pressing, and exhibits excellent physical properties. Discharge plasma sintering is called as various technical names such as FAST (Field Activated Sintering Technology), PECS (Pulsed Electric Current Sintering) and PAS (Plasma Activated Sintering).

In addition to the above-described sintering method, it is of course possible to use apatite hydroxide powder as a target by molding with a molding method such as a conventional die-pressing, injection molding or cold isostatic pressing.

On the other hand, another example of the target can be produced by sintering a mixed powder obtained by mixing apatite hydroxide powder and tricalcium phosphate (β-TCP) powder. For example, a mixed powder obtained by mixing 50 to 60 wt% of hydroxyapatite and 40 to 50 wt% of beta-tricalcium phosphate is sintered.

Another example of the target may be produced by sintering a mixed powder obtained by mixing apatite hydroxide powder, tricalcium phosphate powder and powdery additives. For example, a mixed powder obtained by mixing 50 to 60 wt% of hydroxide apatite, 35 to 45 wt% of beta -phosphate and 1 to 5 wt% of an additive is sintered.

As the additive, calcium oxide (CaO) or phosphorus pentoxide (P ₂ O ₅ ) can be used. It is also possible to use calcium oxide and phosphorus pentoxide mixed as an additive at the same weight ratio.

When the apatite hydroxide target is used to coat the surface of the base material, the calcium and phosphorus components of the target material may be separated from the plasma to lower the chemical uniformity of the coating film. Therefore, calcium oxide (CaO) or phosphorus pentoxide (P ₂ O ₅ ) added to the target is to correct the calcium component and phosphorus component.

2. Coating step

When the target is ready, the coating step is carried out.

In the coating step, a target is placed in the chamber, argon gas is injected, and the target is discharged to form a coating film on the surface of the substrate.

A substrate to form a coating film is prepared to carry out the coating step. After the substrate is prepared, the foreign matter on the surface of the substrate is washed. In order to clean the foreign matter, the substrate is put into the washing container, and then a common washing liquid is injected and the impurities attached to the surface of the substrate are cleaned by using a washing machine. In addition, it can be cleaned using ultrasonic waves in ethanol.

After rinsing process, it is rinsed, dried in a drier to evaporate moisture, and then mounted on a holder installed inside the chamber.

The present invention applies an RF magnetron sputtering method as a method for forming a coating film on the surface of a substrate. Coating can be performed using conventional RF magnetron sputtering equipment.

The chamber is evacuated to 5 x 10 < ^-6 > Torr and argon is then introduced into the chamber and cleaned to remove contaminants from the substrate surface and the target surface. Then, the deposition is performed with the chamber pressure adjusted to 5 to 30 mTorr.

As one example of the deposition conditions, a coating film having a thickness of 0.1 to 2 탆 is formed by sputtering at a power of 100 to 500 W for 1 to 5 hours.

Through the above-described coating step, a coating film having bioactivity can be formed by containing apatite hydroxide on the surface of the substrate.

Hereinafter, the present invention will be described by way of examples. However, the following examples are intended to illustrate the present invention in detail, and the scope of the present invention is not limited to the following examples.

(Example)

60% by weight of hydroxyapatite (HA) powder having a molar ratio of Ca to P of 1.67 and 40% by weight of tricalcium phosphate (? -TCP) were put into a carbon mold of a pressure sintering furnace, Pressure and 1000 캜 for 30 minutes in an Ar gas atmosphere to prepare a target.

Titanium metal having a purity of 99.9% was processed into a disk having a diameter of 15 mm and a height of 3 mm to prepare a substrate. Then, the substrate was ultrasonically cleaned in ethanol for 20 minutes, rinsed in distilled water for 30 minutes, and dried.

The coating process was carried out using an RF magnetron sputtering apparatus (AGS-0408D, A-Tech System, Korea). The chamber was evacuated to 5 × 10 ^-6 Torr after the prepared target and substrate were placed in the chamber (distance between the substrate and the target: 90 mm), and then argon gas was injected to remove contaminants from the substrate surface and the target surface. Plasma cleanings were performed on the substrate for 30 minutes with DC negative bias, followed by sputter cleaning on the target for 10 minutes at 200 W RF power.

Then, argon gas was injected and the chamber pressure was adjusted to 10 mTorr. Then, a 1.2 탆 thick coating film was formed on the surface of the substrate by sputtering with RF power of 130-250 W for 2 hours.

&Lt; Thickness of Coating Film According to RF Power >

The thickness of the coating film was measured according to the change of the RF power under the same conditions, and the results are shown in FIGS. 1 to 5.

FIG. 1 shows a coating film formed with an RF power of 130 W, FIG. 2 shows a coating film formed with an RF power of 160 W, FIG. 3 shows a coating film formed with an RF power of 190 W, And FIG. 5 is a coating film formed with an RF power of 250 W. FIG.

Referring to FIGS. 1 to 5, when the RF power was 130 W, the thickness of the coating layer was about 589 nm, and when the RF power was 250 W, the thickness of the coating layer was about 1.19 μm. Experimental results show that as the RF power increases, the coating thickness becomes thicker.

&Lt; Measurement of adhesion of coating film &

Scratch tests were conducted twice to confirm the adhesion of the coating film formed on the substrate to RF power of 200 W, and the results are shown in FIGS. 6 and 7.

As a result of the experiment, it was confirmed that the adhesion strength of the coating film to the substrate was 7.15N on average, and the adhesion strength of the coating film was excellent.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be clearly understood that the same is by way of illustration and example only and is not to be taken by way of limitation.

Claims

A substrate of ceramic or metal material;
And a coating film formed on the surface of the base material by RF magnetron sputtering and containing apatite hydroxide. The implant according to claim 1, wherein the apatite hydroxide film is formed by RF magnetron sputtering.

[2] The implant according to claim 1, wherein the HA coating layer further comprises beta -triccium phosphate (beta-TCP), wherein the apatite hydroxide coating is formed by RF magnetron sputtering.

The implant according to claim 1, further comprising a buffer layer formed of titanium or titanium nitride between the base material and the coating film to form the apatite hydroxide coating layer by RF magnetron sputtering.

A target preparation step of producing a target containing apatite hydroxide;
And a coating step of forming a coating film on the surface of the ceramic or metal base material by RF magnetron sputtering after the target is installed in the chamber. The RF magnetron sputtering method according to claim 1, &Lt; / RTI >

5. The method of claim 4, wherein the target comprises at least one additive selected from the group consisting of 50 to 60% by weight of the hydroxyapatite, 35 to 45% by weight of tricalcium phosphate (? -TCP), calcium oxide and phosphorus pentoxide % Of the mixed powder is prepared by sintering the mixture powder. The method for manufacturing an implant having the apatite hydroxide coating formed by RF magnetron sputtering.

The method according to claim 4, wherein the coating step is performed by injecting argon gas to maintain the pressure of the chamber at 5 to 30 mTorr, and then sputtering at a power of 100 to 500 W for 1 to 5 hours to form the coating film Wherein the apatite hydroxide film is formed by RF magnetron sputtering.