KR101901980B1 - Porous Surface Having a Triple Structure of at the Macro, Micro and Nanolevel for Improving Osteointegration of Implants and Method for Producing the Same - Google Patents

Abstract

Disclosed is a titanium-based implant for vital implantation having a hydrophilic surface with a large surface area and an appropriate surface roughness, and a manufacturing method thereof. The surface of this implant has a nanoscale, microscale, and macroscopic triple structure. In the nanoscale structure, nanoparticles of titanium oxide form a hydrophilic surface, which is the inner surface of micro-pores of a few micrometers in size formed in the irregularities of the implant surface. These micro scale irregularities form a plurality of depressions with a tensile to several hundreds of micrometers on a macroscopic scale with a curved surface with a surface roughness of the order of 0.5 to 5 mu m. These implants are formed by forming titanium metal or a titanium alloy into a desired shape, impacting inorganic particles on the surface by a method such as sand blasting, acid treatment to form micropores, and then anodizing the titanium oxide nanoparticles And then, if necessary, heat treatment.

Description

TECHNICAL FIELD [0001] The present invention relates to a porous surface for improving the osseointegration ability of an implant having a macroscopic-micro-nano-scale triple structure, and a method for manufacturing the porous surface. the Same}

The present invention relates to dental and surgical implants. More particularly, the present invention relates to a titanium implant surface treated for bone formation and a method of manufacturing the same.

Early dental implants used pure titanium metal implants with a smooth surface. However, when such a smooth surface is used, it sometimes takes a long time for the formation of the osseointegration, or the osseointegration fails. In order to compensate for this, various efforts have been made to improve the osseointegration ability by roughening the surface of the implant. As a result, titanium material with a titanium oxide film has become the most widely used material for dental and orthopedic surgeons to repair teeth and bones. In particular, it has been found that the use of surface treatment implants with a thin film of titanium oxide on the metal surface through surface treatment of the titanium metal material improves bone regeneration ability.

Among the methods for such surface treatment, there is a method of spraying titanium dioxide or alumina particles onto titanium to form irregularities on the surface and to improve surface roughness through acid treatment. This method is the most widely used method of surface treatment of typical implant materials. However, this method is disadvantageous in application to a living body implant since the treated surface shows hydrophobicity. In recent years, research and development have been carried out to improve the osseointegration ability by increasing surface energy or hydrophilicity by widening the surface area of the material by chemical treatment or electrochemical treatment. Efforts have been made to form a hydrophilic structure having a surface area.

Suitable as such hydrophilic materials are titanium dioxide, in particular titanium dioxide. However, in the prior art used for forming the microstructure of the titanium oxide on the surface of the implant, the mechanical properties of the titanium oxide produced were low. Therefore, if the implant is placed in a general procedure, the titanium oxide microstructure is damaged and deformed, and the effect of improving the osseointegration performance of the implant fixture is poor. To improve this problem, even if the mechanical properties of the titanium microstructure are improved through heat treatment, the same problem arises if a general technique (implantation with appropriate load to increase the initial fixing force) is applied. In addition, the formation of these titanium oxide microstructures did not improve the roughness over the entire implant surface, since the surfaces were only machined implants. Therefore, despite the characteristics of titanium oxide, which has excellent hydrophilicity and good bone formation affinity, it has not been widely reflected in the implant products to date.

The technical object of the present invention is to provide a dental and surgical implant having an optimal surface roughness for bone formation and greatly increasing the area of a hydrophilic surface essential for cell and blood compatibility and improving the osteogenesis capacity and reducing the healing period after implantation Titanium implants and a method of manufacturing the same.

According to one aspect of the present invention, there is provided a titanium-based material for bio-implantation having a nanoscale, micro-scale, and macro-scale triple structure on a surface thereof. This titanium-based material is made of a titanium metal or a titanium-based alloy material and has a plurality of concavities and convexities on its surface. The roughness of the surface of the titanium-based material is 1 to 4 탆 when measured under the conditions of cutoff 0.25 and 3 lambda according to ISO 1997 standard Irregular surface. In this titanium-based material, part of its surface is partially covered with titanium oxide nanoparticles. Micropores having a size of 1 to 5 탆 are formed in the irregularities, and a plurality of elliptical depressions having a length of 10 to 200 탆 are formed by forming the irregularities of the irregularities having the micropores to be curved surfaces do. In the titanium-based material, the titanium oxide nanoparticles are coated on the inner surfaces of the micropores.

In one specific embodiment of the present invention, the titanium oxide nanoparticles are nanotubes, nanorods or nanodots. In a more specific embodiment of the present invention, the nanotubes or nanorods are oriented substantially perpendicular to the inner surface of the micropores.

According to another aspect of the present invention, there is provided an implant for implantation of a living body including the aforementioned titanium-based material. This implant can be used in a variety of applications in the dental and surgical field.

According to another aspect of the present invention, there is provided a method of manufacturing the titanium-based implant. The manufacturing method includes forming a titanium-based material of a titanium metal or a titanium-based alloy material into a desired shape, impacting inorganic particles on the surface of the formed titanium-based material to form recesses and protrusions including depressions of a size of several hundreds of micrometers or less Forming a titanium oxide-based material on the surface by etching with an acid to form micropores having a size of less than 5 micrometers on the surface; forming a titanium oxide nanoparticle on the surface by anodizing the multi- And an anodizing step and a heat treatment step of heating the anodized titanium-based material at 350 ° C to 600 ° C.

According to one embodiment of the present invention, in the anodizing step, a voltage of 1 to 30 volts is applied to the titanium-based material as an anode. More specifically, the anodizing step includes a step of applying a fluoride ion ≪ / RTI >

The titanium-based implant of the present invention can easily adjust the surface roughness to a range suitable for osseointegration. In addition, since the implant of the present invention has hydrophilic titanium oxide nanoparticles formed on the inner surface of a porous surface having micro-pores having a size of several micrometers and depressions of a macroscopic scale of several hundreds of micrometers or less, Since the surface area is greatly increased and the blood-friendly hydrophilic surface is provided, the proliferation and differentiation of osteoblasts and the interfacial bonding force between the bone and the implant can be improved, and the healing time after the implant treatment can be greatly reduced. In addition, the titanium oxide nanoparticles are excellent in biocompatibility because they can maintain their shape even under the load generated at the time of implantation, even if the implant procedure is performed by a general procedure. In addition, since the stable oxide titanium oxide film is formed on the surface of the implant, it is excellent in corrosion resistance and can be applied to various materials such as titanium. Thus, it can be widely used for dental and surgical implants, prostheses and fixtures.

1 is a schematic view of the surface of a titanium-based material according to one embodiment of the present invention. Fig. 1 (a) is a schematic diagram showing a low magnification showing a section cut perpendicularly to the surface of the titanium-based material, Fig. 1 (b) is a schematic view of an enlarged inner surface of the micro pores shown in Fig. (c) is an enlarged view of the nanotubes on the inner surface.
2 is an electron micrograph of the surface of a titanium-based material according to one embodiment of the present invention. 2 (a) is a photograph of a magnification of 500 times, and a portion corresponding to a depression is indicated by a dotted line of an ellipse. Fig. 2 (b) is a photograph of enlargement of one of the elliptic dot portions of Fig. 2 (a) at a magnification of 5,000 times, and a portion corresponding to micropores of several micrometers in size is indicated by circles. Fig. 2 (c) shows a nanotube having a diameter of 30 nanometers as a photograph of a magnification of 200,000 times magnified in a circle portion of Fig. 2 (b).
FIG. 3 illustrates nanotubes of various sizes formed in micropores of a surface of a titanium-based material by different conditions according to one embodiment of the present invention.
FIG. 4 is an X-ray diffraction spectrum showing the change in crystallinity of titanium oxide nanoparticles when the heat treatment temperature is varied in the method for producing a titanium-based material according to one embodiment of the present invention.
FIG. 5 is a graph summarizing experimental results obtained by evaluating the bone interface strength of a titanium-based implant according to one embodiment of the present invention by placing it on a rabbit's leg.

Hereinafter, the present invention will be described in more detail.

In one aspect of the present invention, titanium-based materials suitable for dental and surgical implant materials are provided.

The titanium-based material of the present invention is a titanium metal material having a nanostructure including oxide nanoparticles formed on its surface, or a titanium-based alloy containing titanium as a main component. As the titanium-based alloy, those widely used in this field may be used. For example, Ti-Nb-Zr ternary alloy having corrosion resistance and close to the elastic modulus of the bone may be used. However, Do not.

The titanium-based material of the present invention has a triple structure in which nanostructures, microstructure and macrostructure structures are superimposed on the surface. This triple structure has a nanostructure of nano-scale oxide nanoparticles, a microstructure having irregularities with micropores of several micrometers on the inner surface of the nanoparticles, A complex structure ranging from a dimple-shaped macroscopic structure in which uneven surfaces form curved surfaces and form crater-shaped depressions ranging from several tens of micrometers to several hundreds of micrometers. This complex surface structure provides a porous hydrophilic surface favorable for osseointegration.

The surface of the titanium-based material of the present invention is an irregular and non-smooth surface having a plurality of irregularities, at least partially coated with oxide nanoparticles having corrosion resistance and hydrophilicity including titanium oxide.

1 is a schematic view showing a cross-section of a surface of a titanium-based material according to an embodiment of the present invention. Fig. 1 (a) is a schematic diagram showing a low magnification showing a section cut perpendicularly to the surface of the titanium-based material. As shown in Fig. 1 (a), the titanium-based material of the present invention is a non-smooth surface having surface roughness, and a plurality of irregularities form a curved surface. As shown in Fig. 1 (a), the surface roughness is directly related to the height difference between the lowest point and the highest point of the material surface irregularities. The surface of the titanium material shown in Fig. 1 forms a plurality of elliptical depressions having a major axis length of tens to hundreds of micrometers at the dimension of the macro structure. On the other hand, the plurality of irregularities form a micropore of several micrometers in size or not in the depression or the depression. The curved inner surface of the depressed portion is formed with irregularities having such micropores or no micropores. Fig. 1 (b) is an enlarged schematic view of the inner surface of the micropores shown in Fig. 1 (a), and Fig. 1 (c) is a schematic diagram of enlarged nanoparticles on the inner surface. In the embodiment shown in Fig. 1 (c), the nanoparticles are nanotubes whose cross-section is hollow or whose hollow is hollow when the nanoparticles are cut perpendicularly to the longitudinal axis (major axis direction).

In one embodiment of the present invention, the irregular surface has a surface roughness of 1 to 4 占 퐉 when measured under the conditions of cutoff 0.25 and 3 lambda according to ISO 1997 standard. In one embodiment, the length of the long axis of the depressed portion is a plurality of elliptical depressions of 10 to 200 탆. The size of the fine holes is 1 to 5 占 퐉.

In the titanium-based material of the present invention, oxide nanoparticles are coated on the inner surface of the micropores to form a nanostructure. In the present invention, the term " nanoparticles " refers to a collection of aggregates of nanometer-scale particles such as nanotubes, nanorods, and nanodots, and is not specifically limited to nanoparticles.

In one embodiment of the present invention, the nanoparticles are titanium oxide. In one specific embodiment, the titanium oxide of the nanoparticles is crystalline, and in a preferred embodiment, the crystalline titanium oxide is in an anatase or rutile phase.

In one specific embodiment of the present invention, the titanium oxide nanoparticles are nanotubes. Here, the term " nanotube " refers to a longitudinal direction (longitudinal direction or longitudinal direction), and a cross section perpendicular to the longitudinal axis of the nanotube is close to a circle or an ellipse. Refers to a geometry whose width is on the order of nanometers (ie hollow cylinder or other cylindrical shape). In a more specific embodiment of the present invention, the length of the nanotubes is 10 to 200 nm, and the maximum diameter of the cross section perpendicular to the longitudinal axis is 5 to 200 nm. In the titanium material of the present invention, the nanotubes on the same material surface may all have the same cross-section, or the cross-sectional shape may be a mixture of different nanotubes like hollow circles and hollow ellipses. In a more specific embodiment of the present invention, the titanium oxide nanotubes are oriented substantially perpendicular to the inner surface of the micropores. The orientation substantially perpendicular to the inner surface of the micropores in this specification means that the direction of the greatest dimension in the nanotube is precisely aligned with the inner bottom, as well as the orientation of the nanoparticles standing upright at 90 [deg. Orientation that is observed at a slope of less than 90 DEG, for example, a slope of at least 45 DEG with respect to the bottom surface of the micropores.

In another specific embodiment of the present invention, the titanium oxide nanoparticles are nanorods. In this specification, a nanorod is a rod shape which can define a longitudinal direction like the aforementioned nanotube. The maximum width of a cross section perpendicular to the longitudinal axis of the rod is nanometer scale, The shape of the cross-section is not limited to a circle or an ellipse like the nanotube described above, but also includes an ellipse, a circle, a rectangle, and an irregular cross-section. In a more specific embodiment of the present invention, the length of the nanorods is 5 to 50 nm and the maximum diameter of the cross-section cut perpendicular to the longitudinal axis is 5 to 20 nm. In the case of a hollow cylindrical, tortuous, rectangular or irregular Type. In a more specific embodiment of the titanium oxide nanoparticles, the nanorods are oriented substantially perpendicular to the inner surface of the micropores. Fig. 2 (a) shows a nanostructure in which nanorods are covered in the surface of the irregularities of titanium according to this specific embodiment. In the specific form shown in FIG. 2 (a), the cross section of the nanorod is all a rectangular shape. However, as described above, the cross-section may have another shape such as an ellipse or an irregular shape. On the surface of the same titanium material, These different nanorods may be mixed. 2 (a) shows a case in which the nanotube is replaced with a nanorod in FIG. 1 (b) and FIG. 1 (c) Do.

In another specific embodiment of the present invention, the titanium oxide nanoparticles are nanodots having a maximum diameter of 10 nm or less. In this specification, nano-dots refers to nanoparticles representing planes of nanometer scale, in which the axes of two axes are significantly larger than the other axis when defining the three-dimensional orthogonal axes of the nanoparticles. For example, nano-dots are flat nanoparticles with a speck shape whose height or longitudinal axis is much smaller than that of an axis orthogonal thereto. The shape of the spots of the nano dot is not limited to any particular shape such as a circle, an ellipse, a rectangle, and an irregular shape. Fig. 2 (b) shows a nanostructure in which nanodots are coated on the surface of the titanium material of the present invention according to this specific embodiment. 2 (b) shows a case where the nanotubes are substituted with nano-dots in Fig. 1 (b) and Fig. 1 (c) Do.

In another aspect of the present invention, there is provided an implant, a prosthesis, or a fixture for living body implant including such a titanium-based material. In one embodiment, the implant, prosthesis or fixture is for dental use. Examples include, but are not limited to, dental prosthesis, dental orthodontic wire, osteotomy plate, osteotomy screw, artificial tooth, dental crowns, dental bridge, denture frame or fixation screws for dental surgery.

In another embodiment, the implant is for surgery, especially orthopedic. For example, artificial bones, artificial joints, fracture plates, hip joint implants, knee joint implants, shoulder implants, artificial vertebrae, spinal articulating components, But are not limited to, a fracture fixation device, a fracture fixation plate, or a fracture fixation screw.

Another aspect of the present invention discloses a surface treatment method for producing the aforementioned titanium-based material.

The surface treatment method of the titanium-based material for a living body implant

(1) a step of roughening inorganic particles on the surface of a titanium-based material made of a titanium metal or a titanium-based alloy to form recesses and protrusions including depressions of a size of several hundreds of micrometers or less on the surface,

(2) a polycrystalline step of etching the roughened titanium-based material with an acid to form micropores having a size of less than 5 micrometers on the surface,

(3) an anodizing step of forming the titanium oxide nanoparticles on the surface by anodizing the multi-refractory titanium-based material, and

(4) a heat treatment step of heating the anodized titanium-based material at 350 ° C to 600 ° C.

The surface roughening step may use a known method of raising the surface roughness of the titanium-based material by impacting the surface of the titanium-based material with sufficient kinetic energy of the inorganic particles, for example, titanium dioxide or alumina. For example, by sandblasting to form surface irregularities of several tens to several hundreds of micrometers on the surface of a titanium-based material. Thus, the concavo-convex structure including the depression can be formed.

In the subsequent polycrystalline phase, micro-pores of several micrometers are formed in the titanium-based material having the uneven structure. The polycrystalline phase can also use known techniques, for example, acid treatment to etch the surface with acid.

In the anodic oxidation step, nanoparticles of several nanometers to several nanometers in size are formed on the inner surface of the micropores of the titanium-based material having many irregularities with surface micropores. In the anodic oxidation process, the titanium-based material in contact with the electrolyte becomes the anode and the voltage is applied thereto. The negative electrode is not particularly limited, and for example, a platinum electrode or the like can be used. Through the anodic oxidation process, various sizes of porous nanostructures can be formed in the micropores. Various oxide nanoparticles including titanium oxide can be formed by controlling the kind of electrolyte and additives. For example, by using an electrolyte containing fluoride ion (F-), the reaction conditions such as anodization time (10 seconds to 5 hours) or voltage (1 volt to 30 volts) The shape of the structure can be changed. There is no or little change in the structure of the micropores already formed in the anodic oxidation step.

In the subsequent heat treatment step, the formed nanoparticles are improved to a proper physical property for use in the implant. The heat treatment conditions are 350 ° C to 600 ° C. In one specific embodiment, the oxide nanoparticles are titanium dioxide, and the amorphous titanium dioxide before the heat treatment is subjected to a heat treatment step to become a crystalline structure, for example, an anatase phase or a rutile phase.

Another aspect of the present invention discloses a method for manufacturing an implant through a surface treatment method of such a titanium-based material. The method for manufacturing an implant of the present invention can be performed by applying the above-described surface treatment method after molding the titanium-based material into a desired shape.

[ Example ]

Hereinafter, the present invention will be described in more detail with reference to the following examples. However, the following examples are intended to illustrate the present invention, but the scope of the present invention is not limited thereto.

Fig. 2 shows the surface of a titanium-based material according to an embodiment of the present invention in which the nanostructure of the titanium oxide nanotube is formed.

2 (a) is a photograph of a magnification of 500 times, and a portion corresponding to a depression is indicated by a dotted line of an ellipse. Fig. 2 (b) is a photograph of enlargement of one of the elliptic dot portions of Fig. 2 (a) at a magnification of 5,000 times, and a portion corresponding to micropores of several micrometers in size is indicated by circles. Fig. 2 (c) shows a nanotube having a diameter of 30 nanometers as a photograph of a magnification of 200,000 times magnified in a circle portion of Fig. 2 (b).

FIG. 3 is an electron microscope photograph of a titanium-based material having various sizes of nanostructures prepared in the same manner as the titanium material shown in FIG. 2, except that the condition of the anodizing step is changed.

4 is an X-ray diffraction chart showing the effect of the heat treatment step of the present invention on the crystallinity of titanium oxide nanoparticles. It can be seen that the crystal phase changes from amorphous (no heat treatment) to anatase (increase in heat treatment) when a signal of a peak near the diffraction angle of 40 ° rises according to the change of the heat treatment condition indicated in the box.

FIG. 5 is a graph showing the bone interface strength of an implant according to the present invention through an experiment in which an implant made of a titanium-based material according to an embodiment of the present invention is implanted into a rabbit leg and then removed. In FIG. 5, SA is a prior art implant using only a roughening step and a multi-step step without conducting anodizing and heat treatment steps. The Nano SA 30 and Nano SA 70 are the same implants that have undergone the same anodizing and annealing steps as the above SA but with anodizing and heat treatment steps. The Nano SA 30 and Nano SA 70 are 30 nm and 70 nm in diameters of titanium oxide nanotubes, respectively, which are different from each other in the anodic oxidation step.

While the present invention has been particularly shown and described with reference to certain exemplary embodiments thereof, it should be understood that the same is by way of illustration and example only and is not to be taken by way of limitation. It will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention as defined in the appended claims. .

Accordingly, all equivalents of the claims and their equivalents, as well as the embodiments described hereinabove and the appended claims, are also within the scope of the inventive concept.

Claims (22)

As a titanium-based material of a titanium metal or a titanium-based alloy for living body implantation,
The surface of the titanium-based material is an irregular surface having a surface roughness of 0.5 to 5 占 퐉 when measured under the conditions of cutoff 0.25 and 3 lambda according to ISO 1997 standard,
A plurality of depressions having a maximum width in a range of 10 to 300 mu m are formed on the surface, at least a part of the surface is coated with titanium oxide nanoparticles,
Wherein the titanium oxide is a crystalline material and the crystalline titanium oxide is a rutile phase. The titanium-based material according to claim 1, wherein micropores having a maximum width of 1 to 5 탆 are superimposed on an irregular surface having a surface roughness of 0.5 to 5 탆. The titanium-based material according to claim 1, wherein the titanium oxide nanoparticles are nanotubes, nanorods, or nanodots. 4. The nanotube according to claim 3, wherein the nanotube has a length of 10 to 200 nm, a cross section perpendicular to the longitudinal axis is in a hollow circle or hollow circle shape, the maximum diameter of the cross section is 5 to 200 nm Based material. 5. The titanium-based material according to claim 4, wherein the nanotubes are oriented in the inner surface of the titanium-based material surface irregularities. The method of claim 3, wherein the nanorods are 5 to 50 nm in length, Wherein the cross section perpendicular to the axis is a circle, an ellipse or a rectangle, and the maximum diameter of the cross section is 5 to 20 nm. 7. The titanium-based material according to claim 6, wherein the nanorods are oriented perpendicular to an inner surface of the titanium-based material surface irregularities. 4. The titanium-based material according to claim 3, wherein the nanodot has a maximum diameter of 10 nm or less. delete delete 9. An implant comprising the titanium-based material of any one of claims 1 to 8. 12. The implant according to claim 11, wherein the implant is a dental implant. The implant according to claim 12, wherein the implant is selected from a dental prosthesis, a dental orthodontic wire, a jaw replacement plate, a jaw replacement screw, an artificial tooth, a dental crown, a dental bridge, a denture frame, Implants characterized. 12. The implant according to claim 11, wherein the implant is a surgical implant. 15. The method of claim 14, wherein the implant is selected from the group consisting of artificial bone, artificial joint, fracture plate, hip joint implant, implant for knee joint, shoulder implant, artificial vertebrae, spinal articulating wherein the implant is selected from a fracture fixation device, a fracture fixation device, a fracture fixation plate, and a fracture fixation screw. delete delete delete delete delete delete delete

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