WO2013047998A2 - Preparation method of porous implant and porous implant prepared thereby - Google Patents

Abstract

The present invention relates to a preparation method of a medical porous implant and a porous implant prepared thereby, and more specifically, to a preparation method of a porous implant and a porous implant prepared thereby, wherein the preparation method comprises: a filling step of filling a material comprising a metal powder and a ceramic powder into a mold; and a sintering step of applying 100-2,000 kgf/cm² of pressure to the material filled in the mold and simultaneously generating 500-2000 A of current and 3-7 V of voltage using a spark plasma sintering device so as to allow current to flow throughthe material, thereby sintering the material at 800-1,400 ℃. The porous implant is harmless to the human body, and can be prepared within a short time at low temperatures, thereby reducing manufacturing costs.

Description

Method for producing porous implants and porous implants prepared therefrom

The present invention relates to a method for manufacturing a porous implant used for medical purposes and to a porous implant prepared therefrom, and more particularly, the mold using a filling step and an energization sintering device to fill a mold with a metal powder or ceramic powder. Sintering step of sintering the raw material at 800 to 1400 ℃ by energizing the raw material by applying a pressure of 100 to 2000kgf / ㎠ and generating a current of 500 to 2000A and a voltage of 3 to 7V Including, it is to a method for producing a porous implant that can be produced in a short time at a low temperature harmless to the human body and to a manufacturing method and a porous implant prepared therefrom.

Implants are artificial devices designed to replace or act as tissues that have been lost, for example implants that are used in human joints, including orthopedic implants, dental implants, spinal cages, knees and hip joints Ore block, bone support and bone graft material used in bone defects.

In order for the implant to function, the implant should be well integrated with the surrounding bone tissue, and the difference in Young's modulus between the implant and the surrounding bone tissue should be small so that stress shielding does not occur in the surrounding bone tissue. In order for the implant to function effectively, an implant may be manufactured to have a porosity. For example, the macropore of the porous implant may have bone ingrowth, and thus the porous implant may be fixed as compared to a dense tissue implant. The time required for shortening and the fixing force is increased. In addition, the porous implant has a low Young's modulus similar to that of the bone tissue compared to the implant of the dense tissue, so the stress shielding phenomenon does not occur in the surrounding bone tissues after implantation does not cause loss of bone tissue.

A method of manufacturing a porous implant, conventionally a method of obtaining a porous implant by coating tantalum on the carbon skeleton by the method of chemical vapor deposition (Low Temperature Arc Vapor Deposition) to polyurethane foam (PU foam) Method of manufacturing a porous implant using the method of), a method of manufacturing a porous implant by removing the pore precursor after mixing the metal powder and the pore precursor, repeatedly depositing polyurethane foam on a slurry consisting of a metal powder and a binder And a method for producing a porous implant.

However, the chemical vapor deposition method or low temperature arc deposition method for producing a porous implant has to use expensive equipment, there is a problem that the manufacturing process time is increased and the manufacturing cost increases. In addition, the method using a pore precursor or a binder, there is a problem that the toxic pore precursor or binder and the like remains in the implant even after the preparation of the porous implant.

The present invention has been made to solve the above problems,

The present invention is orthopedic implants, dental implants, spinal cages, porous implants used in the joint block, artificial bone joints used in the human joint including the knee and hip joints, bone support used in bone support and bone defects It is an object of the present invention to provide a method for preparing and an implant prepared therefrom.

In addition, the present invention provides a method for producing a porous implant and an implant prepared therefrom, while being firmly fixed to the surrounding bone tissue in a short time, while having a low Young's modulus similar to that of the bone tissue so that stress shielding does not occur in the surrounding bone tissue after transplantation Its purpose is to.

It is also an object of the present invention to provide a method for producing a porous implant, which is not harmful to the human body, by using no pore precursor or a binder at the time of manufacture, and an implant prepared therefrom.

In addition, an object of the present invention is to provide a method for producing a porous implant that can be produced in a short time at a low temperature by using a current-carrying sintering device and an implant manufactured therefrom.

The present invention is implemented by the embodiment having the following configuration to achieve the above object.

According to an embodiment of the present invention, a method for manufacturing a porous implant according to the present invention includes a filling step of filling a mold made of a metal powder or a ceramic powder; Including a sintering step of applying a predetermined pressure to the raw material filled in the mold using an energizing and sintering device and sintering the raw material at a constant temperature by energizing the raw material; including, shortening the manufacturing time and lowering the manufacturing temperature It features.

According to another embodiment of the present invention, the pressure applied in the sintering step in the method for producing a porous implant according to the present invention is characterized in that the 100 to 2000kgf / ㎠.

According to another embodiment of the present invention, the temperature for sintering in the sintering step in the method for producing a porous implant according to the invention is characterized in that 800 to 1400 ℃.

According to another embodiment of the present invention, in the method of manufacturing a porous implant according to the present invention, the sintering step is characterized by applying a current of 500 to 2000A and a voltage of 3 to 7V.

According to another embodiment of the present invention, in the method of manufacturing a porous implant according to the present invention, the metal is titanium, titanium alloy, cobalt chromium, cobalt chromium alloy, tantalum, tantalum alloy, niobium, niobium alloy and titanium nitride It is characterized in that any one or more selected from the group consisting of.

According to another embodiment of the present invention, in the method of manufacturing a porous implant according to the present invention, the ceramic is characterized in that any one or more selected from the group consisting of tricalcium phosphate, hydroxyapatite, zirconia and alumina.

According to another embodiment of the present invention, in the method of manufacturing a porous implant according to the present invention, the mold is characterized in that it is made of one or more selected from the group consisting of graphite, tungsten carbide and tungsten.

According to another embodiment of the present invention, the porous implant according to the present invention is characterized by being manufactured by the manufacturing method according to any one of claims 1 to 4.

According to another embodiment of the present invention, the porous implant according to the present invention is prepared by the method according to any one of claims 1 to 4, characterized in that having a porosity of 10 to 80%.

The present invention can achieve the following effects by the configuration and combination, the use relationship described above in the present embodiment.

The present invention can be used in orthopedic implants, dental implants, spinal cages, artificial bone joints used in human joints including knee and hip joints, bone graft material used in the support of bones and bone defects, etc. There is.

In addition, the present invention is firmly fixed to the surrounding bone tissue in a short time, while having a low Young's modulus similar to the bone tissue has the effect that the stress shielding phenomenon does not occur in the surrounding bone tissue after transplantation.

In addition, the present invention does not use a pore precursor, a binder or the like at the time of manufacture, there is an effect that is not harmful to the human body.

In addition, the present invention can be manufactured in a short time at a low temperature by using the energization sintering device has the effect of reducing the manufacturing cost.

1 is a schematic view of the energization sintering apparatus used in the method for manufacturing a porous implant according to an embodiment of the present invention.

Figure 2 is a flow chart showing a method of manufacturing a porous implant according to an embodiment of the present invention.

Figure 3 is a photograph of a porous implant produced by the manufacturing method according to an embodiment of the present invention.

Figure 4 is a SEM image of the porous implant produced by the manufacturing method according to an embodiment of the present invention.

5 is a graph showing the results of XRD analysis of the porous implant specimen prepared by the manufacturing method according to an embodiment of the present invention.

6 is a SEM photograph showing the appearance of osteoblasts attached to the porous implant specimen prepared by the manufacturing method according to an embodiment of the present invention.

* Explanation of symbols used in the drawings

1: energizing and sintering device 11: casing 12: mold

13: Punch 14: Pressing portion 15: Power supply portion

2: raw material 3: porous implant

Hereinafter, a method for manufacturing a porous implant according to the present invention and a porous implant prepared therefrom will be described in detail with reference to the accompanying drawings. Unless otherwise defined, all terms in this specification are equivalent to the general meaning of the terms understood by those of ordinary skill in the art to which the present invention pertains and, if they conflict with the meanings of the terms used herein, Follow the definition used in the specification.

Figure 1 is a schematic diagram of the energizing and sintering apparatus used in the method for manufacturing a porous implant according to an embodiment of the present invention.

Hereinafter, with reference to Figure 1, after describing the energizing and sintering apparatus 1 used to manufacture the porous implant according to the present invention, to explain a method for manufacturing a porous implant using the energizing and sintering apparatus (1). do.

The energizing and sintering device 1 is a device for applying a pressure to the raw material (2) made of a powder inserted therein and directly through electricity to sinter the raw material (2) at a predetermined temperature to make a product, the casing (11) , Mold 12, punch 13, pressurizing means 14, power supply unit 15, and control unit (not shown).

The casing 11 forms an outer shape of the energizing and sintering device 1 and accommodates the mold 12 and the punch 13 therein, and the inside of the casing 11 is maintained in a vacuum state when manufacturing the product.

The mold 12 is configured to accommodate a raw material 2 such as metal powder or ceramic powder, which is a raw material of a product, and is inserted into the casing 11. The mold 12 includes a hollow 121 penetrated up and down, and the punch 13 is installed at the upper and lower ends of the hollow 121 to move upward and downward, respectively. The raw material (2) is located in the space (S) formed by the hollow 121 and the punch 13, the product is manufactured, by deforming the shape of the hollow 121 and punch 13 Products of various shapes can be produced. The mold 12 is formed of an electrically heat-resistant material such as graphite, tungsten oxide or tungsten.

The punch 13 is installed in the upper and lower ends of the hollow 121 of the mold 12 so as to be movable, respectively, and the end of the punch 13 is coupled to the pressing means 14 to be described later. The punch 13 is formed of an electrically heat-resistant material such as graphite, tungsten oxide or tungsten.

The pressing means 14 is connected to the punch 13, and provides a driving force for allowing the punch 13 to move up and down in the hollow 121 of the mold 12.

The power supply unit 15 is configured to generate electricity to allow electricity to flow in the raw material 2 in the mold 12, the power supply unit 15 is the pressing means 14, punch 13, the mold 12 Is electrically connected). When the power supply unit 15 is operated to allow electricity to be supplied to the raw material 2 in the mold 12, heat is generated to cause the raw material 2 to be sintered.

The control unit (not shown) is configured to control the overall operation of the energization and sintering apparatus 1, by operating the pressing means 14 to press the raw material 2 or to operate the power supply unit 14 to the raw material (2) It plays a role in making electricity flow.

Figure 2 is a flow chart showing a method for manufacturing a porous implant according to an embodiment of the present invention, Figure 3 is a photograph of a porous implant prepared by a manufacturing method according to an embodiment of the present invention, Figure 4 is a view of the present invention SEM image of the porous implant prepared by the manufacturing method according to an embodiment, Figure 5 is a graph showing the XRD analysis of the porous implant specimen prepared by the manufacturing method according to an embodiment of the present invention, Figure 6 SEM image showing the appearance of osteoblasts attached to the porous implant specimen prepared by the manufacturing method according to an embodiment of the present invention.

1 to 6, a method for manufacturing a porous implant according to an embodiment of the present invention comprises a raw material preparation step (S1) for preparing a raw material (2) made of metal powder or ceramic powder; A mold and punch preparation step (S2) for preparing the mold 12 and the punch 13 to form a space S into which the raw material 2 is inserted; A filling step (S3) of filling the mold 12 with the prepared raw material 2; Sintering step (S4) of applying a constant pressure to the raw material (2) filled in the mold 12 using the energization sintering device (1) and energizing the raw material (2) to sinter the raw material (2) at a predetermined temperature (S4) Including, it is possible to manufacture a porous implant in a short time at a low temperature harmless to the human body has a feature that can reduce the manufacturing cost.

The raw material preparation step (S1) is a step of preparing a raw material for manufacturing a porous implant, a metal powder and / or ceramic powder of 10 to 2000㎛ size is used as the raw material and the raw material has a spherical or irregular shape Can have.

The metal powder is titanium, titanium alloy, cobalt chromium, cobalt chromium alloy, tantalum, tantalum alloy, niobium, Any one or more metal powder selected from the group consisting of niobium alloy and titanium nitride may be used.

The ceramic powder may be any one or more ceramic powders selected from the group consisting of tricalcium phosphate, hydroxyapatite, zirconia, and alumina.

The mold and punch preparation step (S2) is a step of preparing the mold 12 and the punch 13 to form a space S into which the raw material 2 is inserted to have a specific shape. The punch 13 is made of an electrically heat-resistant material such as graphite, tungsten oxide or tungsten. Since the raw material 2 is located in the space S formed by the mold 12 and the punch 13 to manufacture a product, the shape of the mold 12 and the punch 13 may be deformed and variously desired. It is possible to manufacture a shaped product.

The filling step (S3) is a step of filling the raw material 2 in the mold 12 prepared in the mold and punch preparation step (S2), inserting the raw material into the hollow 121 of the mold 12 and the hollow The punch 13 is coupled to the top and bottom of the 121 so as to be movable.

In the sintering step (S4), a constant pressure is applied to the raw material 2 filled in the mold 12 using the energization and sintering device 1, and the raw material 2 is energized to sinter the raw material 2 at a predetermined temperature. In the step, it comprises a mold insertion step (S41), a vacuum composition step (S42), the pressurizing and energizing step (S43).

In the mold inserting step S41, the mold 12 into which the raw material 2 is inserted in the filling step S3 and the punch 13 is inserted into the casing 11 of the energization sintering device 1 The punch 13 is connected to the pressing unit 14.

The vacuum composition step (S42) is a step of making a vacuum atmosphere inside the casing 11 after the mold insertion step (S41).

The pressurizing and energizing step S43 is a step of pressing and energizing the raw material 2 in the mold 12 and sintering at a predetermined temperature, which is controlled by the controller. The pressurizing and energizing step S43 is generated by the control unit operating the pressurizing unit 14 to push the punch 13 to pressurize the raw material 2 in the mold 12 and generate electricity at the power supply unit 15. Electricity flows along the pressurizing portion 14, the punch 12, and the mold 11 to energize the raw material 2. In the pressurizing and energizing step (S43), since the raw material 2 is pressurized and electricity is flowed through the punch, the mold, and the raw material, Joule heat is generated, and thus the raw material is locally dissolved and combined. In other words, a porous implant having a plurality of pores formed therein.

In the pressurizing and energizing step S43, it is preferable to apply a pressure of 100 to 2000 kgf / cm 2, sinter at a temperature of 800 to 1400 ° C., and generate electricity of a current of 500 to 2000 A and a voltage of 3 to 7 V. .

In addition, the present invention includes a porous implant prepared by the method for producing a porous implant. The implant preferably has a porosity of 10 to 80%. Figure 3 is an example of the porous implant (3) prepared by the method of manufacturing the porous implant, as can be seen in the SEM photograph of the porous implant (3) of Figure 4, it can be seen that a number of pores are formed. . The porous implant 1 may have various shapes by changing the shape of the mold 12 and the punch 13, as well as the pores by controlling the particle size of the raw material in the manufacturing method, the pressure applied in the sintering step, etc. The size and porosity of the can be easily adjusted.

Hereinafter, the present invention will be described in more detail with reference to Examples. However, these are only intended to describe the present invention in more detail, but the scope of the present invention is not limited thereto.

<Example 1>

1) Prepare 400 ~ 500㎛ irregular titanium powder, insert into mold and connect punch.

2) Insert the mold into the casing of the energization and sintering device to connect the pressing means to the punch and to vacuum the inside of the casing.

3) Pressurizing means to pressurize the raw material to 500kgf / ㎠, generate a 5V voltage and 1700A current to sinter the raw material to 1100 ℃ to prepare a cylindrical specimen 13mm in diameter, 25mm in length of the porous implant It was.

<Example 2>

Specimens of porous implants were prepared under the same conditions as in Example 1 except for using irregular titanium powders of 300 to 400 μm.

<Example 3>

Specimens of porous implants were prepared under the same conditions as in Example 1 except that irregular titanium powders of 500 to 600 µm were used.

<Example 4>

Specimens of porous implants were prepared under the same conditions as in Example 1 except for using irregular titanium powders of 900 to 1000 μm.

Example 5

A specimen of a porous implant was prepared under the same conditions as in Example 1 except that the raw material was pressed at 200 kgf / cm 2.

<Example 6>

A specimen of a porous implant was prepared under the same conditions as in Example 1 except that the raw material was pressed at 1000 kgf / cm 2.

Comparative Example 1

1) Comparative Example 1 is a conventional method for producing a porous implant, 400 ~ 500 ㎛ of irregular titanium powder and a polyvinyl butyral binder is prepared and inserted into the mold, about 500kgf / Pressurized to 2 cm 2 to produce a molded article.

2) The molded body was subjected to a binder burnout at 600 ° C. in a vacuum sintering furnace, followed by sintering at 1100 ° C. and cooling to prepare a porous implant.

Experimental Example 1 Measurement of Physical Properties and Manufacturing Time of Prepared Porous Implants

Test purpose: Measurement of physical properties and manufacturing time of the prepared porous implants

-Test method: Porosity, yield strength and production time of Examples 1 to 6 and Comparative Example 1 were measured and shown in Table 1 below. The porosity (P) is expressed by the formula P (%) = (1-Db / Dth) * 100 (Db (g / cm 3) = M (g) / V (cm 3), Db is bulk density, Dth is theoretical density, M is Mass, V, by volume). The yield strength was tested at a test speed of 0.123 mm / min using a universal machine (Instron), and the yield strength was measured from the stress-strain curve obtained after the test. The preparation time was measured for the total time from preparing the raw material to preparing the specimen of the porous implant.

-Confirmation of results: Compared to Examples 1 to 6 and Comparative Example 1 in Table 1, the porosity and yield strength is almost no difference, while the production time of Examples 1 to 6 is significantly shorter, from the manufacturing method of the present invention In the case of manufacturing a porous implant according to the present invention can be confirmed that it is possible to manufacture a porous implant that is significantly shorter the manufacturing time, but there is no difference in physical properties with the porous implant prepared by the conventional method.

In Examples 1 to 6, it can be seen that as the raw material size increases, the porosity increases, and as the pressure increases, the porosity decreases and the yield strength increases. From this, the desired porosity and yield strength can be obtained by adjusting the raw material size and pressure. It can be seen that the porous implant can be prepared.

Table 1 division Manufacture conditions Test evaluation Manufacturing time (hr) Raw material size (㎛) Pressure (kgf / ㎠) Porosity (%) Yield strength (MPa) Example 1 400-500 500 46.9 29.7 2 Example 2 300-400 500 49 29.9 2 Example 3 500-600 500 43.5 27.7 2 Example 4 900-1000 500 40.6 36.4 2 Example 5 400-500 200 53.2 8.4 2 Example 6 400-500 1000 39.5 80.6 2 Comparative Example 1 400-500 500 47 24.9 30

Experimental Example 2 Measurement of Chemical Properties and Measurement of Biocompatibility of Prepared Porous Implants

-Test purpose: Determination of changes in chemical properties and biocompatibility of prepared porous implants

Test Method: The specimen of Example 1 (a), the specimen of Example 6 (b) and the raw material (c) were analyzed by XRD and shown in FIG. 5 (using Phillips' X'Pert-MPD System). The specimen of 1 was transplanted into the test animal, removed 7 days later, and photographed by SEM and shown in FIG. 6 (using Hitachi S-2400).

-Confirmation of results: Referring to FIG. 5, the components of Example 1 (a), Example 6 (b) and the raw material (c) are the same, and from this, impurities are produced during the manufacturing process using the energization sintering apparatus. It can be seen that there is no change in chemical composition due to penetration. 6, it can be seen that the osteoblasts penetrate the pores and the pores are filled. From this, it can be seen that the osteoblasts are also attached to the porous implants prepared by using the sintering device.

In the above, the Applicant has described various embodiments of the present invention, but these embodiments are merely one embodiment for implementing the technical idea of the present invention, and any changes or modifications may be made to the present invention as long as the technical idea of the present invention is implemented. It should be interpreted as falling within the scope of.

Claims (9)

A filling step of filling the mold with a raw material made of metal powder or ceramic powder; Including a sintering step of applying a predetermined pressure to the raw material filled in the mold using an energizing and sintering device and sintering the raw material at a constant temperature by energizing the raw material; including, shortening the manufacturing time and lowering the manufacturing temperature Method for producing a porous implant, characterized in that. According to claim 1, wherein the pressure applied in the sintering step Method for producing a porous implant, characterized in that 100 to 2000kgf / ㎠. The method of claim 1, wherein the temperature sintered in the sintering step is Method for producing a porous implant, characterized in that 800 to 1400 ℃. The method of claim 1, wherein in the sintering step Method for producing a porous implant, characterized in that for applying a current of 500 to 2000A and a voltage of 3 to 7V. The method of claim 1, wherein the metal is Method for producing a porous implant, characterized in that any one or more selected from the group consisting of titanium, titanium alloys, cobalt chromium, cobalt chromium alloys, tantalum, tantalum alloys, niobium, niobium alloys and titanium nitride. The method according to any one of claims 1 to 4, wherein the ceramic Method for producing a porous implant, characterized in that any one or more selected from the group consisting of tricalcium phosphate, hydroxyapatite, zirconia and alumina. The mold according to any one of claims 1 to 4, wherein the mold is Method for producing a porous implant, characterized in that it is made of one or more selected from the group consisting of graphite, tungsten carbide and tungsten. It is manufactured by the manufacturing method in any one of Claims 1-4, The porous implant characterized by the above-mentioned. A porous implant produced by the method according to any one of claims 1 to 4, having a porosity of 10 to 80%.

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