JP2011045559A - Implant material, method for producing the same, and method for improving affinity of the implant material to osteocyte - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an implant material which suppresses osteoclast induction and promotes differentiation to osteoblast. <P>SOLUTION: The implant material includes a substrate 10, and a carbonaceous thin film 20 formed on the surface of the substrate 10. The carbonaceous thin film 20 contains at least one selected from an oxygen-containing functional group and a nitrogen-containing functional group. The abundance ratio of the oxygen-containing functional group is not more than 4% and the ratio of the abundance ratio of the nitrogen-containing functional group to the abundance ratio of the oxygen-containing functional group is not more than 10. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an implant material, a method for producing the same, and a method for improving affinity with bone cells, and particularly relates to a material that requires affinity for bone cells such as artificial roots and dentures and a method for producing the same.

  Currently, titanium and titanium alloys are used as a base material for implants to be embedded in living bodies such as artificial tooth roots because they are excellent in biocompatibility, corrosion resistance and mechanical strength. However, if an artificial dental root made of titanium or titanium alloy is directly fixed to the jawbone, the metabolic balance of bone tissue regeneration of the jawbone may be lost, and the artificial root may loosen or the jawbone may be destroyed. Are known.

  As a cause of the failure of such artificial tooth root implantation, there is peri-implantitis in which osteoclasts are induced around the artificial tooth root and bone destruction occurs. Peri-implantitis may result from microbial stimulation such as bacterial infection and mechanical stimulation such as excessive bite force, but also occurs due to osteoclast activation by the artificial tooth root itself.

  The activation of osteoclasts by the artificial tooth root also occurs at the time of initial implantation of the implant. Osteoclasts that appear at the time of initial implantation interfere with the osseointegration of the implant and cause the implant to fail.

  Such activation of osteoclasts is considered to be caused by the fact that titanium and titanium alloys do not have sufficient affinity with bone cells. On the surface of a material having insufficient affinity for bone cells, differentiation from osteoclast precursor cells to osteoclasts is promoted, thereby causing bone destruction. Titanium and titanium alloys are known to have relatively high affinity for bone cells. However, it cannot be said that the affinity is sufficient, and the implantation of the artificial tooth root fails due to the condition of the jaw bone of the person to be implanted, the condition in the oral cavity, and the like.

  As a method for improving the affinity between an implant such as an artificial tooth root and a bone cell, an attempt has been made to coat with a diamond-like thin film (DLC film) (see, for example, Patent Document 1). The DLC film has carbon as a main component and has a smooth and inert surface, so that it is excellent in compatibility with a living body. For this reason, it is thought that it is excellent also in the affinity with a bone cell.

JP 2002-204825 A

  However, the affinity between the implant and the bone cell needs to be examined not only from the suppression of osteoclast induction but also from the viewpoint of promoting differentiation into osteoblasts. Even if the differentiation from osteoclast precursor cells to osteoclasts can be suppressed, if the differentiation from immature osteoblasts to osteoblasts is suppressed or the proliferation of osteoblasts is inhibited, the osseointegration of the implant Is not promoted. To date, little is known about how the DLC membrane affects osteoblast differentiation.

  The present invention suppresses the induction of osteoclasts and promotes the differentiation into osteoblasts based on the knowledge of the effect of the DLC film on the differentiation into osteoblasts obtained by the inventors of the present application. An object of the present invention is to realize a material for implants.

  Specifically, the implant material according to the present invention includes a base material and a carbonaceous thin film formed on the surface of the base material, and the carbonaceous thin film includes at least a functional group containing oxygen and a functional group containing nitrogen. The ratio of the functional group containing oxygen is 4% or less, and the value obtained by dividing the abundance ratio of the functional group containing nitrogen by the abundance ratio of the functional group containing oxygen is 10 or less. To do.

  According to the study by the present inventors, it has at least one of a functional group containing oxygen and a functional group containing nitrogen, the abundance ratio of the functional group containing oxygen is 4% or less, and the presence of a functional group containing nitrogen On the surface of the carbonaceous membrane where the ratio / the ratio of oxygen-containing functional groups is 10 or less, differentiation into osteoblasts is likely to occur, and differentiation into osteoclasts is difficult to occur. For this reason, the implant material of the present invention can suppress differentiation into osteoclasts and promote differentiation into osteoblasts, thereby realizing an implant material with excellent affinity with bone tissue. it can.

  In the implant material of the present invention, the base material may be a metal. Moreover, it is preferable that a base material consists of titanium or a titanium alloy.

  In the implant material of the present invention, the base material may be an artificial tooth root, a denture, a crown restoration, an artificial bone, or an artificial joint.

  In the implant material of the present invention, the zeta potential on the surface of the carbonaceous film may be −50 mV or more and less than 0 mV.

  The method for producing an implant material according to the present invention includes a step (a) of preparing a base material, and a step of forming a carbonaceous film on the surface of the base material by a chemical vapor deposition method using a gas containing a hydrocarbon. (B) and a step (c) for maintaining the substrate in a vacuum state until the dangling bonds on the surface of the carbonaceous film formed on the surface of the substrate are stabilized, and a function including oxygen in the carbonaceous film The abundance ratio of groups is 4% or less, and the value obtained by dividing the abundance ratio of functional groups containing nitrogen by the abundance ratio of functional groups containing oxygen is 10 or less.

  The method for producing an implant material of the present invention may further include a step (d) of irradiating the carbonaceous film with plasma of a basic nitrogen-containing compound after the step (c).

  In the method for improving the affinity of an implant material according to the present invention with bone cells, a carbonaceous film having at least one of a functional group containing oxygen and a functional group containing nitrogen is formed on the surface of a base material, The abundance ratio of the group is 4% or less, and a value obtained by dividing the abundance ratio of the functional group containing nitrogen by the abundance ratio of the functional group containing oxygen is 10 or less.

  According to the carbon thin film and the method for producing the same according to the present invention, an implant material that suppresses induction into osteoclasts and promotes differentiation into osteoblasts can be realized.

FIG. 6 is a cross-sectional view illustrating an exemplary implant material. It is a graph which shows the relationship between the surface state of a base material, and the proliferation of an osteoblast. It is a graph which shows the relationship between the surface state of a base material, and the differentiation to an osteoblast. It is a graph which shows the relationship between the surface state of a base material, and the differentiation to an osteoblast. It is a graph which shows the relationship between the surface state of a base material, and the differentiation to an osteoclast.

  In this embodiment, the implant includes not only an artificial tooth root but also a denture, a crown restoration material, a denture restoration material, and the like. In addition to dental use, it also includes instruments that need to be compatible with bone cells, such as artificial bones and artificial joints, that are implanted in a living body.

The carbonaceous film is a film containing sp ² carbon-carbon bonds (graphite bonds) and sp ³ carbon-carbon bonds (diamond bonds) represented by diamond-like films (DLC films). It may be an amorphous film such as a DLC film or a crystalline film such as a diamond film. Usually, it contains sp ² carbon-hydrogen bonds and sp ³ carbon-hydrogen bonds, but hydrogen is not an essential component. Further, silicon (Si), fluorine (F), or the like may be added.

  FIG. 1 shows a cross-sectional configuration of the implant material according to the present embodiment. A carbonaceous film 20 having a film thickness of about 0.005 μm to 3 μm is formed on the surface of the substrate 10. At least one of a functional group containing oxygen typified by a carboxyl group and a functional group containing nitrogen typified by an amino group is present on the surface of the carbonaceous film 20. In the present embodiment, the abundance ratio of the functional group containing oxygen in the carbonaceous film 20 is 4% or less. Further, the value obtained by dividing the abundance ratio of the functional group containing nitrogen by the abundance ratio of the functional group containing oxygen is 10 or less. As will be described in detail later, the abundance ratio of the functional group containing oxygen refers to the peak area of the 1s (O1s) peak of oxygen obtained by X-ray photoelectron spectroscopy as the peak area of the 1s (C1s) peak of carbon. The abundance ratio of the functional group containing nitrogen is a value obtained by dividing the peak area of the 1s (N1s) peak of nitrogen by the peak area of the 1s (C1s) peak of carbon.

  Implant materials are very important for their affinity with bone cells. Affinity with bone cells refers to both the promotion of differentiation from immature osteoblasts to osteoblasts, the promotion of osteoblast proliferation, and the suppression of induction from osteoclast precursor cells to osteoclasts. It is necessary to evaluate from.

  A carbonaceous film is formed on the surface of the substrate, and the abundance ratio of functional groups including oxygen such as carboxyl groups on the surface of the carbonaceous film is 4% or less, and the abundance ratio of functional groups including nitrogen such as amino groups is carboxyl. By dividing the value divided by the abundance ratio of the functional group containing oxygen such as a group to 10 or less, it is possible to promote differentiation into osteoblasts, promote osteoblast proliferation, and suppress induction into osteoclasts. The present inventors have found that can be realized.

  Differentiation from immature osteoblasts to osteoblasts when the ratio of functional groups containing oxygen is 4% or less and the ratio of functional groups containing nitrogen / the ratio of functional groups containing oxygen is 10 or less The reason why the induction of osteoclasts is suppressed is not clear. However, when the abundance ratio of the functional group containing oxygen is 4% or less and the abundance ratio of the functional group containing nitrogen / the abundance ratio of the functional group containing oxygen is larger than 10 and the abundance ratio of the functional group containing nitrogen / oxygen When the abundance ratio of the functional group containing is 10 or less and the abundance ratio of the functional group containing oxygen is higher than 4%, osteoblasts proliferate, but promotion of differentiation into osteoblasts is not recognized. From this, it is considered that the affinity of bone cells is controlled by the balance between the carboxyl group and the amino group on the surface of the carbonaceous membrane.

  In the treatment of dental implants, it is known that platelets have a great influence on treatment results. For example, it is known that treatment is more reliably performed by immersing the implant in platelet-rich plasma obtained from the patient's blood before the implant is placed and adsorbing the platelet to the surface of the implant. It has been. On the other hand, the abundance ratio of the amino group and the carboxyl group on the surface of the carbonaceous film affects the zeta potential on the surface of the carbonaceous film, and the value of the zeta potential zeta potential on the surface of the carbonaceous film is −50 mV or less. In this case, it is known that platelets hardly adsorb. Zeta in the case where the abundance ratio of the carboxyl group which is a functional group containing oxygen is 4% or less and the abundance ratio of the amino group which is a functional group containing nitrogen / the abundance ratio of the carboxyl group which is a functional group containing oxygen is 10 or less The value of the potential is about −60 mV to 0 mV. Therefore, the zeta potential on the surface of the carbonaceous film is preferably −50 mV or more and 0 mV or less.

  Since the implant material of this embodiment covers the surface of the base material with a carbonaceous film, the material for the implant shows excellent affinity with bone tissue regardless of the material of the base material. For this reason, the base material may be any material as long as it satisfies characteristics such as strength. For example, metals such as titanium and titanium alloys, resins, ceramics, and the like can be used. In addition, it can be applied to various implants that require affinity for bone cells such as artificial tooth roots, dentures, artificial bones, and artificial joints.

  The carbonaceous film may be formed by a chemical vapor deposition method (CVD method). Further, it may be formed by sputtering, plasma ion implantation, ion plating, arc ion plating, ion beam vapor deposition, laser ablation, or the like other than CVD.

  Oxygen and moisture present in the chamber during and after the formation of the carbonaceous film cause functional groups containing oxygen such as carboxyl groups on the surface of the carbonaceous film. For this reason, when the abundance ratio of the functional group containing oxygen is 4% or less, it is preferable to use a high-purity raw material gas during film formation and to supply the raw material gas via an adsorption dehydrator or the like. . Further, in order to suppress the bond with oxygen after the film formation is completed, it is preferable that the dangling bond of the carbonaceous film is stabilized by maintaining the film in a vacuum for a certain time immediately after the film formation is completed. For example, when a carbonaceous film is formed by plasma CVD, the purity of the argon gas used for plasma generation is set to 99.9999% or more, and after the film formation is finished, the substrate temperature becomes room temperature, preferably at least 10 minutes. May be left in a vacuum for 60 minutes or longer.

When it is necessary to introduce a functional group containing nitrogen such as an amino group into the carbonaceous film, the carbonaceous film may be irradiated with plasma of a basic nitrogen-containing compound. Examples of the basic nitrogen-containing compound include ammonia and organic amines having a general formula represented by NR ₁ R ₂ R ₃ (where R ₁ , R ₂ and R ₃ are hydrogen, —CH ₃ , —C ₂ H ₅ , —C ₃ H ₇ or —C ₄ H ₈ , and R ₁ , R ₂ and R ₃ may be the same or different from each other.) Or benzylamine and its secondary and tertiary amines Etc. may be used. However, ammonia is preferable because of cost and ease of handling. Note that the ultimate vacuum in the chamber during plasma irradiation may be about 0.01 Pa to about 500 Pa. However, it is preferable that the ultimate vacuum is higher without being affected by oxygen in the air, and may be about 5 × 10 ⁻³ Pa.

  When a functional group containing oxygen needs to be further introduced into the carbonaceous film, oxygen plasma or plasma of gas containing oxygen may be irradiated. Further, the ultimate vacuum at the time of irradiation with plasma such as ammonia may be lowered.

  Note that a plasma irradiation apparatus having any structure may be used. Also, any type of discharge may be used. For example, a parallel plate method, an after glow discharge method, an electromagnetic induction type, a magnetic field type, or the like may be used. Plasma irradiation conditions are not particularly limited. For example, as the power source for generating plasma, various power source frequencies such as a commercial frequency (50 Hz or 60 Hz), a high frequency (radio frequency), or a microwave region can be used. Furthermore, the pressure control method and supply structure of the source gas are not particularly limited. However, if plasma irradiation conditions with a very high etching rate are used, the carbonaceous thin film may be damaged.

  The thickness of the carbonaceous film is not particularly limited, but is preferably in the range of 0.005 μm to 3 μm, more preferably in the range of 0.01 μm to 1 μm.

  In addition, the carbonaceous film can be directly formed on the surface of the base material, but an intermediate layer is provided between the base material and the carbonaceous thin film in order to more firmly adhere the base material and the carbonaceous thin film. Also good. As the material for the intermediate layer, various materials can be used depending on the type of substrate, but silicon (Si) and carbon (C), titanium (Ti) and carbon (C), or chromium (Cr) and carbon. A known film such as an amorphous film made of (C) can be used. Although the thickness is not specifically limited, the range of 0.005 micrometer-0.3 micrometer is preferable, More preferably, it is the range of 0.01 micrometer-0.1 micrometer. The intermediate layer may be formed using, for example, a sputtering method, a CVD method, a plasma CVD method, a thermal spraying method, an ion plating method, an arc ion plating method, or the like.

(Example)
Hereinafter, the implant material of the present embodiment will be described in more detail using examples.

-Formation of carbonaceous film-
A carbonaceous film made of a DLC film was formed on the surface of a base material made of pure titanium (JIS type 2). A substrate with a diameter of 20 mm was used for cell culture. The DLC film was formed using a chemical vapor deposition (CVD) method. Specifically, C ₂ H ₂ was introduced into the chamber on which the substrate was placed so that the flow rate was 150 sccm (cm ³ / min, but 1 atm, 0 ° C.) and the pressure was 24.67 Pa (35 mTorr). Then, high frequency power of 100 W to 500 W was applied to the RF electrode.

After the DLC film is formed, the DLC film having a low abundance ratio of oxygen-containing functional groups can be obtained by leaving it in a vacuum. Table 1 shows the abundance ratio of the functional group containing oxygen and the abundance ratio of the functional group containing nitrogen when the DLC film is left in a vacuum for 10 minutes after being formed and in a vacuum for 120 minutes. . Note that the functional group containing oxygen is regarded as a carboxyl group (COOH), and the functional group containing nitrogen is regarded as an amino group (NH ₂ ) for evaluation. The abundance ratio of the functional group containing oxygen can be reduced to 4% or less by leaving it in a vacuum for 10 minutes or more after film formation. In addition, the longer the time of leaving in vacuum, the smaller the abundance ratio of the functional group containing oxygen.

−官能基の導入−
炭素質膜に官能基をさらに導入するためにプラズマ照射を行った。プラズマ照射は平行平板型のプラズマ照射装置により行った。プラズマ照射装置のチャンバ内に上記で得られた基材をセットした後、チャンバ内の圧力を２Ｐａ以下まで排気した。次に、チャンバ内にアンモニア又は酸素を所定の流量で導入し、平行平板電極の間に３０Ｗの高周波電力を印加することによりプラズマを発生させた。ガス流量の調整はマスフローコントローラにより行い、プラズマ照射時のチャンバ内圧力は１３０Ｐａとした。高周波電力は、マッチングボックスを介して接続された高周波電源を用いて印加した。窒素を含む官能基の導入にはアンモニアを用い、酸素を含む官能基の導入には酸素を用いた。プラズマ照射時間は１５秒とした。

-Introduction of functional groups-
Plasma irradiation was performed to further introduce functional groups into the carbonaceous film. Plasma irradiation was performed by a parallel plate type plasma irradiation apparatus. After setting the base material obtained above in the chamber of the plasma irradiation apparatus, the pressure in the chamber was evacuated to 2 Pa or less. Next, ammonia or oxygen was introduced into the chamber at a predetermined flow rate, and plasma was generated by applying high frequency power of 30 W between the parallel plate electrodes. The gas flow rate was adjusted by a mass flow controller, and the pressure in the chamber during plasma irradiation was 130 Pa. The high frequency power was applied using a high frequency power source connected via a matching box. Ammonia was used to introduce a functional group containing nitrogen, and oxygen was used to introduce a functional group containing oxygen. The plasma irradiation time was 15 seconds.

-Evaluation of functional group abundance ratio-
The abundance ratio of functional groups in the carbonaceous film was evaluated by X-ray photoelectron spectroscopy (XPS) measurement. An aluminum Kα ray was used as the X-ray source, the acceleration voltage was 10.0 KV, and the emission current was 10 mA. The incident angle of X-rays was 45 degrees, and the state from the surface to a depth of about 4 nm was measured.

The abundance ratio of the functional group containing nitrogen was the ratio of the area of the 1s (N1s) peak of nitrogen and the area of the carbon (C) 1s peak obtained in XPS measurement. It is not clear what state nitrogen is present on the surface of the carbonaceous film. However, it is considered that functional groups containing nitrogen (nitrogen functional groups) such as amino groups and amide groups are formed. Although detailed analysis of the nitrogenous functional group is difficult, it is considered that it exists mainly as an amino group because an N1s peak appears in the vicinity of 399 eV in XPS measurement. Hereinafter, the ratio of the area of the N1s peak to the area of the C1s peak will be described as the abundance ratio [NH ₂ ] of the amino group.

  The abundance ratio of the functional group containing oxygen was the ratio of the area of the oxygen 1s (O1s) peak obtained in the XPS measurement to the area of the C1s peak. A hydroxyl group other than a carboxyl group may be formed as a functional group containing oxygen, but in the following, the ratio of the area of the O1s peak to the area of the C1s peak is referred to as a carboxyl group abundance ratio [COOH]. .

  In XPS measurement, the abundance ratio obtained from the ratio of peak areas is atomic% (at%).

-Evaluation of osteoblasts-
The sample was cultured in contact with a mouse osteoblast-like cell line MC3T3-E1 cell (hereinafter referred to as MC3T3-E1 cell) in a well having a diameter of 20 mm. Cells were seeded at 5 × 10 ⁴ cells per well. As the culture medium, α-modified Eagle medium (α-MEM) containing 10% fetal bovine serum (FBS), L-glutamine, mixed antibiotics (manufactured by Invitrogen) and 50 μg / ml ascorbic acid was used. The culture temperature was 37 ° C., and the culture was performed in a 5% carbon dioxide atmosphere.

  After culturing the cells for one day, the number of cells was evaluated by MTS (Multiple target screening) method. The wavelength of absorbance measurement for evaluating proliferation was 490 nm.

  After culturing the cells for 7 days, the expression of Runx2 and Type I collagen (CoI-I), which are bone differentiation marker genes, was evaluated. Specifically, RNA was extracted from cultured MC3T3-E1 cells using TRIzol reagent (Invitrogen), and then cDNA was prepared using ReverTra Ace reverse transcriptase (Toyobo). The prepared cDNA was evaluated by quantitative RT-PCR (Rela-time Quantitative Reverse Transcriptase-Polymerase Chain Reaction) method.

-Evaluation of differentiation of bone destructive cells-
In the well, the sample and osteoclast precursor cells were contacted in the presence of an osteoclast differentiation inducing factor (Receptor Activator of NF-kB Ligand: RANKL) and cultured at 37 ° C. As the osteoclast precursor cells, cell line RAW264.7 cells (TIB-71, ATCC) that have been established to differentiate into osteoclasts in the presence of RANKL were used. Cells were seeded at 5 × 10 ³ cells per well.

  Differentiation into osteoclasts was evaluated by quantifying the expression of cathepsin K, which is a differentiation-related gene, using a quantitative RTPCR method.

-Measurement results-
Measurement was performed on four samples shown in Table 2. Sample 1 is a pure titanium base material on which a DLC film provided for control is not formed. Sample 2 is a DLC film not subjected to plasma irradiation. Sample 3 is a DLC film in which the amount of carboxyl groups introduced is increased by plasma irradiation. Sample 4 is a DCL film in which the amount of amino groups introduced is increased by plasma irradiation.

図２は、ＭＣ３Ｔ３−Ｅ１細胞の増殖特性を示している。図２において縦軸は４９０ｎｍの吸光度を示し、吸光度が高いほどＭＣ３Ｔ３−Ｅ１細胞が増殖していることを示す。図２に示すように、ＤＬＣ膜を形成してもＭＣ３Ｔ３−Ｅ１細胞の増殖性は低下しなかった。また、ＤＬＣ膜に導入した官能基の量によってもＭＣ３Ｔ３−Ｅ１の増殖性は影響を受けなかった。

FIG. 2 shows the growth characteristics of MC3T3-E1 cells. In FIG. 2, the vertical axis indicates the absorbance at 490 nm, and the higher the absorbance, the more the MC3T3-E1 cells are proliferating. As shown in FIG. 2, the proliferation of MC3T3-E1 cells did not decrease even when a DLC film was formed. In addition, the proliferation of MC3T3-E1 was not affected by the amount of functional groups introduced into the DLC film.

3 and 4 show the differentiation characteristics of MC3T3-E1 cells. In FIG. 3, the vertical axis indicates the mRNA expression level of Runx2, and the larger the value, the more Runx2 is expressed and the differentiation of MC3T3-E1 cells is promoted. In FIG. 4, the vertical axis represents the amount of CoI-I mRNA expression, and the larger the value, the more CoI-I is expressed and the differentiation of MC3T3-E1 cells is promoted. In sample 2, the expression levels of Runx2 and CoI-I increased about 200 times that of pure titanium. However, in sample 3 with [COOH] exceeding 4% and sample 4 with [NH ₂ ] / [COOH] exceeding 10, no effect of promoting differentiation into osteoblasts was observed.

FIG. 5 shows the expression characteristics of cathepsin K, which is an index of differentiation into osteoclasts. In both sample 1 and sample 2, when RANKL, which is a differentiation promoting factor, is not present, the expression level of cathepsin K is small, and differentiation from osteoclast precursor cells to osteoclasts is suppressed. Yes. However, in the presence of RANKL, in the case of sample 1, the expression level of cathepsin K increased to 9 times or more that in the absence of RANKL, and differentiation from osteoclast progenitor cells to osteoclasts occurred actively. On the other hand, in the sample 2 having a carbonaceous film having [COOH] of 4% or less and [NH ₂ ] / [COOH] of 10 or less, the increase in the expression level of cathepsin K was slight. This revealed that a carbonaceous film having [COOH] of 4% or less and [NH ₂ ] / [COOH] of 10 or less can suppress differentiation from osteoclast precursor cells to osteoclasts.

  The implant material and the production method thereof according to the present invention can realize an implant material that suppresses induction into osteoclasts and promotes differentiation into osteoblasts, and in particular, bone cells such as artificial tooth roots and dentures. It is useful as a dental material that requires an affinity for and a manufacturing method thereof.

10 Substrate 20 Carbonaceous film

Claims (8)

A substrate;
A carbonaceous film formed on the surface of the substrate;
The carbonaceous film has at least one of a functional group containing oxygen and a functional group containing nitrogen,
The abundance ratio of the functional group containing oxygen is 4% or less,
A value obtained by dividing the abundance ratio of the functional group containing nitrogen by the abundance ratio of the functional group containing oxygen is 10 or less.   The implant material according to claim 1, wherein the base material is made of metal.   The implant material according to claim 1, wherein the base material is made of titanium or a titanium alloy.   The implant material according to any one of claims 1 to 3, wherein the base material is an artificial tooth root, a denture, a crown restoration, an artificial bone, or an artificial joint.   The implant material according to any one of claims 1 to 4, wherein a zeta potential on the surface of the carbonaceous film is -50 mV or more and less than 0 mV. Preparing a substrate (a);
A step (b) of forming a carbonaceous film on the surface of the substrate by chemical vapor deposition using a gas containing hydrocarbon;
(C) holding the substrate in a vacuum state until dangling bonds on the surface of the carbonaceous film formed on the surface of the substrate are stabilized,
The abundance ratio of the functional group containing oxygen in the carbonaceous film is 4% or less, and the value obtained by dividing the abundance ratio of the functional group containing nitrogen by the abundance ratio of the functional group containing oxygen is 10 or less. A method for manufacturing an implant material.   The method for producing an implant material according to claim 6, further comprising a step (d) of irradiating the carbonaceous film with plasma of a basic nitrogen-containing compound after the step (c). . Forming a carbonaceous film having at least one of a functional group containing oxygen and a functional group containing nitrogen on the surface of the substrate;
An implant characterized in that the abundance ratio of the functional group containing oxygen is 4% or less, and a value obtained by dividing the abundance ratio of the functional group containing nitrogen by the abundance ratio of the functional group containing oxygen is 10 or less. A method for improving the affinity of materials with bone cells.

Images