WO2008032931A1

WO2008032931A1 - Apparatus and method for forming bone filler

Info

Publication number: WO2008032931A1
Application number: PCT/KR2007/003740
Authority: WO
Inventors: Kwang Bum Park; Kyoung Ho Ryoo; Seok Kyu Choi; Dong Jun Yang; Hyun Wook An; Jae Won Kim
Original assignee: Megagen Co., Ltd.
Priority date: 2006-09-11
Filing date: 2007-08-03
Publication date: 2008-03-20
Also published as: KR100677871B1

Abstract

Provided are an apparatus and a method for forming a bone filler. The apparatus includes: a bone filler receptor cell including a bone filler containing space and a drain nozzle through which the bone filler is drained; and a compressor draining the bone filler through the drain nozzle. Thus, a bone filler can be formed in a predetermined shape through a process of compressing and draining the bone filler in a slurry state. Thus, a variation possibility of a physical property of the bone filler can be considerably reduced in a sintering process, and the hardness of the bone filler can be easily adjusted. Also, an unnecessary loss of a material of the bone filler can be reduced, and sharp parts that may damage an organic cell cannot be formed on a surface of the bone filler.

Description

APPARATUS AND METHOD FOR FORMING BONE FILLER

Technical Field

[1] The present invention relates to an apparatus and a method for forming a bone filler, and more particularly, to an apparatus and a method for forming a bone filler by which a variation possibility of a physical property of the bone filler can be removed in a sintering process, the hardness of the bone filler can be easily adjusted, unnecessary losses of materials of the bone filler can be reduced, and a sharp surface that may damage an organic cell cannot be formed at the bone filler. Background Art

[2] In general, if a part of an osseous tissue of a specific site in an organism is defected or is required to be reinforced, a bone is implanted into the osseous tissue of the specific site. If the bone is implanted into the organism as described above, the implanted bone induces a new bone to be generated in the specific site, and a part or a whole part of the implanted bone is slowly decomposed. Thus, if a predetermined period of time elapses after the implantation of the bone, the specific site is filled with the new bone.

[3] Here, the bone implanted into the organism is generally a mixture of a part extracted from the osseous tissue of the organism and an artificial bone that is artificially made out of a material such as ceramics, etc. The artificial bone is usually referred to as a bone filler or a bone substitute.

[4] Such a bone filler is made out of a calcium phosphate compound that is a ceramic material. Components of the calcium phosphate compound are similar to components of a bone of an organism composed of main elements, phosphorus (P) and calcium (Ca). Thus, even if the calcium phosphate compound is implanted into the organism, the calcium phosphate compound induces a generation of a new bone not a physiological, immune rejection inside the organism. According to a report, besides the ceramic material, calcium sulfate (CaSO 4 ) and calcium carbonate (CaCO 3 ) are also stable as materials implanted into an organism. [5] The bone filler is formed using a manufacturing method including processes of making a material of the bone filler into slurry (a mixture of a fluent solid containing insoluble solid particles in a suspension state and a liquid) and sintering, grinding, and sifting the material of the bone filler. The process of making the material of the bone filler into the slurry refers to a process of mixing and agitating the material of the bone filler, a micro-pore forming agent that forms a micro-pore in the bone filler, etc. in order to making the material of the bone filler into the slurry. The sintering process is a process of sintering the bone filler in the slurry state at a high temperature to form a hard tissue. The grinding and sifting process is a process of grinding the sintered bone filler to an appropriate size and then sifting the grinded bone filler.

[6] According to the above-described conventional method of manufacturing the bone filler, if the calcium phosphate compound is used as a material of the bone filler, a very high sintering temperature is required to appropriately harden the calcium phosphate compound. Thus, a physical property of the calcium phosphate compound, in particular, a dissolution speed, varies inside an organism, and it is difficult to adjust the hardness of the bone filler.

[7] Also, since the conventional method includes the grinding and sifting process, a bone filler that is not grinded to an unnecessary appropriate size cannot be used and thus must be discarded. Therefore, an unnecessary loss of the material of the bone filler occurs, and sharp parts are formed on a surface of the grinded bone filler and thus stimulate and damage an organic cell. Disclosure of Invention Technical Problem

[8] The present invention provides an apparatus and a method for forming a bone filler by which a variation possibility of a physical property of the bone filler can be removed in a sintering process, the hardness of the bone filler can be easily adjusted, an unnecessary loss of a material of the bone filler can be reduced, and a sharp surface that may damage an organic cell cannot be formed at the bone filler.

Advantageous Effects

[9] According to the present invention, a bone filler can be formed in a predetermined shape using a process of compressing and draining a bone filler in a slurry state. Thus, a variation possibility of a physical property of the bone filler can be removed in a sintering process, and the hardness of the bone filler can be easily adjusted. Also, an unnecessary loss of a material of the bone filler can be reduced, and sharp parts that may damage an organic cell cannot be formed on a surface of the bone filler. Brief Description of the Drawings

[10] FIG. 1 is a block diagram of a bone filler manufacturing system including a bone filler forming apparatus according to an embodiment of the present invention.

[11] FIG. 2 is an exploded perspective view of a bone filler forming apparatus according to an embodiment of the present invention.

[12] FIG. 3 is a cross-sectional view of the bone filler forming apparatus of FIG. 2.

[13] (a) of FIG. 4 is an enlarged view of portion A of FIG. 3.

[14] (b) of Fig. 4 is a plan view of the portion A of FIG. 3.

[15] FIG. 5 is a cross-sectional view of a piston of the bone filler forming apparatus of FIG. 2 that goes up to the top. [16] FIG. 6 is a cross-sectional view of the bone filler forming apparatus of FIG. 2 into which a bone filler is injected.

[17] FIG. 7 is a side view of the bone filler forming apparatus of FIG. 6.

[18] FIG. 8 is a partial cross-sectional view illustrating a process of forming a bone filler using the bone filler forming apparatus of FIG. 2, according to an embodiment of the present invention. [19] FIG. 9 is an enlarged perspective view of a bone filler formed using the bone filler forming apparatus of FIG. 2.

[20] FIG. 10 is a cross-sectional view of a grinding apparatus of the bone filler manufacturing system of FIG. 1, according to an embodiment of the present invention. [21] FIG. 11 is a scanning electron microscope (SEM) photograph of a bone filler grinded by the grinding apparatus of FIG. 10. [22] FIG. 12 is a flowchart of a method of manufacturing a bone filler, including a method of forming a bone filler using the bone filler forming apparatus of FIG. 2, according to an embodiment of the present invention. [23] FIG. 13 is a flowchart of the method of forming the bone filler using the bone filler forming apparatus of FIG. 2, according to an embodiment of the present invention.

Best Mode for Carrying Out the Invention [24] According to an aspect of the present invention, there is provided an apparatus for forming a bone filler, including: a bone filler receptor cell including a bone filler containing space and a drain nozzle through which the bone filler is drained; and a compressor draining the bone filler through the drain nozzle. [25] The apparatus may futher include a macro-pore former combined with the bone filler receptor cell to form a macro-pore in a center of the bone filler. [26] The macro-pore former may include: a macro-pore core keeping a distance from an outlet of the drain nozzle to be positioned in a center of the outlet; and a macro-pore former body installed in the bone filler receptor cell to support the macro-pore core. [27] A cross-section of the macro-pore former body may be smaller than that of the bone filler receptor cell so that the bone filler passes between the bone filler receptor cell and the macro-pore former body. [28] The bone filler receptor cell may be a cylinder comprising an end at which the drain nozzle is provided, and the compressor may be a piston that goes up and down in contact with an inner wall of the cylinder. [29] The drain nozzle may be a slanting nozzle that is connected to the end of the cylinder and thus of which diameter is gradually reduced along a longitudinal direction of the cylinder. [30] A packing may be combined with a lower end of the piston to seal an interior of the cylinder.

[31] The piston may include: a piston rod installed in the cylinder to go up and down inside the cylinder and compressing the bone filler; and a handle provided at the piston rod. The apparatus may further include: a penetration tube combined with an upper end of the cylinder and through which the piston rod penetrates; an elastic body disposed above the penetration tube; and a penetration tube receptor containing the penetration tube and the elastic body and combined with the cylinder to rotate.

[32] The bone filler may include: a calcium phosphate compound, calcium sulfate (CaSO

), or calcium carbonate (CaCO ); and a micro-pore forming agent mixed with the

4 3 calcium phosphate compound to form a micro-pore in the bone filler in a sintering process. [33] The calcium phosphate compound may be tricalcium phosphate (TCP, Ca (PO ) ), tetracalcium phosphate (TeCP, Ca O(PO) ), dicalcium phosphate dihydtate (DCPD,

CaHPO₄(H₂O)₂), or hydroxyapatite (HA, Ca₅(POp₃(OH)₂). [34] The micro-pore forming agent may be poly methyl meta acrylate (PMMA), starch, ornaphthalene ( C H ).

[35] A diameter of the macro-pore may be within a range between IOOD and 100OD.

[36] According to another aspect of the present invention, there is provided a method of forming a bone filler, including: injecting a bone filler into a space of a bone filler receptor cell comprising a drain nozzle draining the bone filler; compressing the injected bone filler; and draining the bone filler through the drain nozzle. [37] The bone filler may be drained through a macro-pore core provided in a center of the drain nozzle to form a macro-pore in a center of the bone filler.

Mode for the Invention [38] The attached drawings for illustrating preferred embodiments of the present invention are referred to in order to gain a sufficient understanding of the present invention, the merits thereof, and the objectives accomplished by the implementation of the present invention. [39] Hereinafter, the present invention will be described in detail by explaining preferred embodiments of the invention with reference to the attached drawings. [40] FIG. 1 is a block diagram of a bone filler manufacturing system including a bone filler forming apparatus according to an embodiment of the present invention.

Referring to FIG. 1, a bone filler manufacturing system 1000 according to the present embodiment is used to manufacture a bone filler having a porous structure and includes a mixing apparatus 100, a forming apparatus 200, a drying apparatus 300, a cutting apparatus 400, a sintering apparatus 500, and a grinding apparatus 600. The mixing apparatus 100 mixes a material of the bone filler and additives and makes the mixture into slurry. The forming apparatus 200 forms the bone filler in the slurry state in a predetermined shape. The drying apparatus 300 dries the formed bone filler. The cutting apparatus 400 cuts the dried bone filler to a predetermined length. The sintering apparatus 500 sinters the cut bone filler. The grinding apparatus 600 grinds the sintered bone filler.

[41] The mixing apparatus 100 uniformly mixes the material of the bone filler, a micropore forming agent, and other additives to make the bone filler into the slurry. The mixing apparatus 100 may be a tank type mixing apparatus that agitates a mixture through an impeller rotated by a motor so that the mixture has a uniform composition, however, the present invention is not limited thereto. The mixing apparatus 100 may be any apparatus that uniformly mixes a bone filler and makes the mixed bone filler into slurry.

[42] The material of the bone filler may be a calcium phosphate compound, calcium sulfate (CaSO 4 ), or calcium carbonate (CaCO 3 ), however, the present invention is not limited thereto. Hereinafter, a case where the calcium phosphate compound is used as the material of the bone filler will be described. This description may be equally applied to cases whether CaSO and CaCO are used as the material of the bone filler. [43] The calcium phosphate compound may be tricalcium phosphate (TCP, Ca 3 (PO 4 ) 2 ), tetracalcium phosphate (TeCP, Ca O(PO) ), dicalcium phosphate dihydtate (DCPD, CaHPO (H 0) ), or hydroxyapatite (HA, Ca (PO ) (OH) ), however, the present

4 2 2 5 4 3 2 invention is not limited thereto.

[44] The micro-pore forming agent is mixed with the calcium phosphate compound and then volatilized in a process (that will be describe later) of sintering the bone filler using the sintering apparatus 500 so as to form a micro-pore in the bone filler. The bone filler may have a porous structure due to the micro-pore. Thus, if the bone filler is implanted into an organism, blood easily permeates into the micro-pore to assist a bone to be effectively generated. The micro-pore forming agent may be poly methyl meta acrylate (PMMA), starch, or naphthalene (C H ), however, the present invention is not

10 8 limited thereto.

[45] The other additives include a solution making the material of the bone filler into slurry, a sintering additive improving a sintering force of the bone filler, a vesicant assisting the micro-pore to be formed, etc. The solution may be cast-oil, the sintering additive may be poly ethylene glycol (PEG), and the vesicant may be hydrogen peroxide (H O ), however, the present invention is not limited thereto.

[46] The forming apparatus 200 will now be described with reference to FIGS. 2 through

9.

[47] FIG. 2 is an exploded perspective view of the forming apparatus 200 forming a bone filler according to an embodiment of the present invention, FIG. 3 is a cross- sectional view of the forming apparatus 200 of FIG. 2, (a) of FIG. 4 is an enlarged view of portion A of FIG. 3, and (b) of FIG. 4 is a plan view of the portion A of FIG. 3. FIG. 5 is a cross-sectional view of a piston of the forming apparatus 200 of FIG. 2 that goes up to the top. FIG. 6 is a cross-sectional view of the forming apparatus 200 of FIG. 2 into which a bone filler is injected, and FIG. 7 is a side view of the forming apparatus 200 of FIG. 6. FIG. 8 is a partial cross-sectional view illustrating a process of forming a bone filler using the forming apparatus 200 of FIG. 2, and FIG. 9 is an enlarged perspective view of a bone filler formed by the forming apparatus 200 of FIG. 2.

[48] The forming apparatus 200 forms the bone filler, which has been made into the slurry by the mixing apparatus 100, into a predetermined shape and includes a bone filler receptor cell, i.e., a cylinder 210 of the present embodiment, a piston 220, a macro-pore former 230, a penetration tube 240, an elastic body 250, and a penetration tube receptor 260. The cylinder 210 contains the bone filler. The piston 220 compresses and drains the bone filler. The macro-pore former 230 forms a macro-pore in the drained bone filler. The penetration tube 240 is combined with an upper end of the cylinder 210 to support the piston 220. The elastic body 250 provides elasticity to the penetration tube 240. The penetration tube receptor 260 contains the penetration tube 240 and the elastic body 250.

[49] The cylinder 210 is an element that contains the bone filler that is mixed in the slurry state by the mixing apparatus 100 and includes a cylinder body 211 that contains the bone filler and a drain nozzle 213 that drains the bone filler.

[50] The cylinder body 211 provides a space that contains the bone filler. For this purpose, a bone filler containing space 215 is provided inside the cylinder body 211. A plurality of uneven portions 217 may protrude from an outer surface of a lower portion of the cylinder body 211 so as to easily hold the cylinder 210.

[51] The drain nozzle 213 is an element that drains the bone filler contained in the cylinder body 211. For this purpose, an outlet 213a is formed at a lower end of the drain nozzle 213 to drain the bone filler. A shape and a size of the bone filler drained through the drain nozzle 213 are determined depending on a shape and a size of the outlet 213a.

[52] In the present embodiment, the outlet 213a has a circular shape and a diameter of lmm but is not limited thereto. Thus, the outlet 213a may have a closed curve, and the size of the outlet 213a may vary. Also, one outlet 213a is provided in the present embodiment, however, the present invention is not limited thereto. Thus, a plurality of outlets 213a may be provided in one forming apparatus 200 to simultaneously drain and form a plurality of bone fillers. [53] The drain nozzle 213 is a slanting nozzle of which diameter is gradually reduced along a longitudinal direction of the cylinder body 211. Thus, the drain nozzle 213 may receive a stronger compressive force in a process of compressing and draining the bone filler, and the macro-pore former 230 that will be described later may be easily installed inside the cylinder 210.

[54] The piston 220 is an element that compresses and drains the bone filler contained in the cylinder 210 and includes a piston rod 222, a piston handle 224, and a packing 226. The piston rod 222 goes up and down inside the cylinder 210 to compress the bone filler. The piston handle 224 is provided at an upper end of the piston rod 222 to assist a user to easily hold the piston 220. The packing 226 is provided at a lower end of the piston rod 222 to seal an interior of the cylinder 210.

[55] The piston rod 222 is an element that goes up and down inside the cylinder 210 to compress the bone filler contained in the cylinder 210 and includes an end connected to the piston handle 224 and an other end connected to the packing 226. Thus, the piston rod 222 transmits a pressure applied to the piston handle 224 to the packing 226 to compress the bone filler.

[56] The piston handle 224 is an element that assists the user to easily hold the piston

220 and effectively transmits a force to the piston rod 222. For this purpose, the piston handle 224 has a bar shape to be substantially perpendicular to the piston rod 222.

[57] The packing 226 is an element that assists the piston rod 222 to compress the bone filler in contact with an inner wall of the cylinder 210. Therefore, the packing 226 is formed of a rubber material having high elasticity in order to increase the contact with the cylinder 210, however, the present invention is not limited thereto. Thus, the packing 226 may be formed of other materials having elasticity. Also, a packing groove 226a is formed in an upper portion of the packing 226, and thus the packing 226 has a cylindrical shape. Thus, when the lower end of the piston rod 222 is inserted into the packing groove 226a, the packing 226 receives a pressure from the piston rod 222 and transmits the pressure to the bone filler contained in the cylinder 210.

[58] As described above, in the present embodiment, the piston 220 is used to compress the bone filler contained in the cylinder 210, however, the present invention is not limited thereto. The piston 220 may be any structure that compresses the bone filler contained in the cylinder 210 to drain the bone filler from the cylinder 210 as in a hydro-pneumatic method.

[59] The macro-pore former 230 is an element that forms the macro-pore in the bone filler drained from the cylinder 210 and includes a macro-pore core 232 that forms the macro-pore in the bone filler and a macro-pore former body 234 that supports the macro-pore core 232.

[60] The macro-pore core 232 is an element that forms the macro-pore in the bone filler drained through the outlet 213a of the drain nozzle 213. Here, if the bone filler is implanted into an organism, body fluids with blood permeate into the macro-pore, like the micro-pore formed by the micro-pore forming agent. Thus, a new bone is effectively generated and a site to which the generated new bone cell adsorbs is provided so as to prevent the generated new bone cell from separating from the organism. The macro-pore is formed using a different method as that by which the micro-pore is formed but substantially performs the same function as the micro-pore. Thus, the macro-pore may be regarded as a kind of micro-pore and thus given its name macro- pore from this point of view. The macro-pore core 232 is provided in a cylindrical shape and has an end positioned in the center of the outlet 213a in order to form the macro-pore in the bone filler. In the present embodiment, the macro-pore core 232 has a circular cross-section and a diameter between IOOD and 100OD, however, the present invention is not limited thereto.

[61] The macro-pore former body 234 is an element that supports the macro-pore core

232 protruding from a lower portion of the macro-pore former body 234 so as to be installed inside the cylinder 210. For this purpose, the macro-pore former body 234 has a rectangular shape and is simply installed at an upper end of an inner portion of the drain nozzle 213 due to geometric structures of the macro-pore former body 234 and the drain nozzle 213. In other words, if the macro-pore former body 234 is positioned at the upper end of the inner portion of the drain nozzle 213, edges formed at four sides of the macro-pore former body 234 contact an inner wall of the drain nozzle 213. In this state, the drain nozzle 213 is a slanting nozzle of which diameter is reduced downward, and thus the macro-pore former body 234 cannot move downward any more. Thus, since the macro-pore former body 234 is not fixed inside the cylinder 210 using a coupling method, the macro-pore former 230 may separate from the cylinder 210.

[62] As shown in (b) of FIG. 4, a space 215a is formed between the macro-pore former body 234 installed inside the cylinder 210 and the inner wall of the cylinder 210. Thus, the bone filler can be drained through the drain nozzle 213 without being interrupted by the macro-pore former body 234.

[63] As described above, the forming apparatus 200 of the present embodiment includes one outlet 213 and one macro-pore core 232 to form one macro-pore in the bone filler, however, the present invention is not limited thereto. Therefore, the forming apparatus 200 may include a plurality of macro-pore cores 232 to form a plurality of macro-pores in the bone filler.

[64] The penetration tube 240 is an element that supports the piston rod 222 to allow the piston rod 222 to smoothly go up and down. Thus, the penetration tube 240 has a structure into which the piston rod 222 is inserted. Also, the penetration tube 240 includes an upper penetration tube 242 having a larger diameter than an inner diameter of the cylinder 210 and a lower penetrating tube 244 having a smaller diameter than the inner diameter of the cylinder 210. Thus, the lower penetration tube 244 is inserted into the upper end of the cylinder 210 so as to stably support the piston rod 222 that moves up and down through the penetration tube 240.

[65] The elastic body 250 is an element that provides an elastic force to the penetration tube 240 in a process (that will be described later) of injecting the bone filler into the cylinder 210. If the penetration tube 240 moves upward to inject the bone filler into the cylinder 210, the elastic body 250 contacts an upper surface of the penetration tube 240 and thus is compressed so as to provide the elastic force to the upper surface of the penetration tube 240.

[66] The penetration tube receptor 260 is an element that contains the penetration tube

240 and the elastic body 250. For this purpose, a penetration tube containing groove 264 is formed in the penetration tube receptor 260. Also, a penetration tube receptor handle 262 is provided at an upper end of the penetration tube receptor 260 so as to easily hold the penetration tube receptor 260.

[67] A process of injecting the bone filler into the forming apparatus 200 having the above-described structure to form the bone filler will now be described. The process of injecting the bone filler into the forming apparatus 200 will be first described.

[68] As shown in FIG. 5, if the user hooks fingers on the piston handle 224 to fully pull the piston rod 222 in an +X direction, the packing 226 combined with the lower end of the piston rod 222 contacts the lower penetration tube 224. If the user further pulls the piston rod 222 in the +X direction, the lower penetration tube 244 separates from the cylinder 210. Here, the elastic body 250 is compressed to provide the elastic force to the upper penetration tube 242 in a -X direction.

[69] In this state, if the cylinder 210 rotates at an angle of 90°in a Y direction, longitudinal directions of the piston rod 222 and the cylinder 210 are perpendicular to each other as shown in FIGS. 6 and 7. Thus, even if an external force pulling the piston rod 222 in the +X direction is removed, the penetration tube 240 receives a force in the -X direction from the elastic body 250 that is compressed. Thus, the piston 220 and the cylinder 210 keep contacting each other at a right angle.

[70] If the piston 220 and the cylinder 210 keep perpendicular to each other due to the elastic force provided from the elastic body 250 as described above, the user may hold only the cylinder 210 to inject the bone filler into the bone filler containing space 215 of the cylinder 210.

[71] If the bone filler is completely injected into the cylinder 210, the user pulls the piston rod 222 in the +X direction again and then rotates the cylinder 210 at an angle of 90 in the Y direction in order to position the piston rod 222 and the cylinder 210 in a line. Next, the user pushes the piston rod 222 in the -X direction so that the lower penetration tube 244 is combined with the cylinder 210 and a lower portion of the piston rod 222 is positioned inside the cylinder 210. As a result, the forming apparatus 200 returns to the state shown in FIG. 3.

[72] As described above, the user can use the forming apparatus 200 of the present embodiment to pull the piston 220 and rotate the cylinder 210 at the angle of 90 so as to easily inject the bone filler into the cylinder 210. Next, the user can re-rotate the cylinder 210 at the angle of 90 to return the cylinder 210 to the original state so as to perform a subsequent process of forming the bone filler. Thus, a time required for manufacturing the bone filler can saved, and the convenience of the user can be increased.

[73] The process of forming the bone filler using the forming apparatus 200 will now be described.

[74] As shown in FIG. 8, if the piston rod 222 compresses a bone filler B contained in the cylinder 210 downward, the bone filler B goes down due to the compressive force of the piston rod 222 and is drained through the outlet 213a so as to form a bone filler B as shown in FIGS. 8 and 9. Here, an end of the macro-pore core 232 is positioned in the center of the outlet 213a, and thus a macro-pore P having the same shape as a cross-section of the macro-pore core 232 is formed inside the bone filler B . Thus, an outer diameter D 4 of the bone filler B 2 is equal to a diameter D 2 of the drain nozzle 213, and a diameter D of the macro-pore P is equal to a diameter D of the macro-pore core 232.

[75] As described above, if a bone filler is formed using the forming apparatus 200 of the present embodiment, the bone filler may be sintered at a lower temperature between 100⁰C and 200⁰C than a bone filler that is not compressed and formed, in a subsequent sintering process that will be described later. The reason is why the subsequent sintering process is to heat particles to supply energy for coupling the particles. Therefore, if the bone filler is compressed before being sintered, distances among the particles constituting the bone filler become closer. As a result, the energy necessary for coupling the particles may be reduced.

[76] If a bone filler is sintered at a low sintering temperature as described above, a variation possibility of a physical property of a calcium phosphate compound that is a material of the bone filler is considerably reduced. If the physical property of the bone filler, in particular, a decomposition speed of the bone filler varies in an organism, the bone filler may not be decomposed at an appropriate speed when the bone filler is implanted into the organism to generate a new bone. Thus, the new bone may not be effectively generated. In an embodiment of the present invention, a sintering temperature of a bone filler can be lowered to effectively induce a new osseous tissue to be generated.

[77] Also, a selection range of the sintering temperature of the bone filler can be increased in a process of sintering the bone filler due to the lowering of the sintering temperature of the bone filler. As a result, it is easily adjust the hardness of the bone filler depending on the sintering temperature.

[78] Like a micro-pore formed by a micro-pore forming agent, the macro-pore P formed in the bone filler formed by the forming apparatus 200 of the present embodiment operates as a path through which blood is supplied and a bone is transmitted when the bone filler is implanted into an organism. Thus, the macro-pore P promotes a generation of a new bone and provides a site to which the new bone adsorbs, so as to prevent the new bone from separating from the organism. The shape and size of the macro-pore core 232 can be adjusted to accurately adjust a shape and a size of the macro-pore P according to the intensions of the user.

[79] The forming apparatus 200 of the present invention forms a bone filler to a predetermined size. Thus, a process of sorting out a bone filler having a size appropriate for being implanted into an organism is not required due to the process of grinding and sifting the bone filler. In a conventional method of manufacturing a bone filler, necessarily including a grinding and sifting process, a part of the bone filler is not grinded to an appropriate size and thus is discarded. As a result, an unnecessary loss of a material of the bone filler occurs. However, in the present invention, such an unnecessary loss of a material of a bone filler can be reduced.

[80] The drying apparatus 300 dries the bone filler B formed by the forming apparatus

200 to lower the viscosity of the bone filler B so as to make the bone filler B into a cuttable state. The drying apparatus 300 is a heater such as a hot air dryer or a vacuum dryer and dries a bone filler for 1 to 2 hours at a temperature between 100⁰C and 200⁰C.

[81] The cutting apparatus 400 cuts the dried bone filler to a length between 0.5mm and

1.5mm. The bone filler is cut to a relatively short length as described above so as to be adaptively implanted even into a narrow site of an organism. Thus, the cutting apparatus 400 may be a laser cutter or a water zet cutter capable of precisely performing cutting in order to cut the bone filler within a short length range, however, the present invention is not limited thereto.

[82] The sintering apparatus 500 sinters the cut bone filler at a high temperature so that the bone filler has predetermined hardness and volatilizes the micro-pore forming agent uniformly mixed with the calcium phosphate compound in the sintering process to 3-dimensionally form the micro-pore in the bone filler. Here, a sintering temperature may be within a range between 1000⁰C and 1200⁰C, and sintering may be performed for 1 to 2 hours. [83] The grinding apparatus 600 will now be described with reference to FIGS. 10 and

11. FIG. 10 illustrates the grinding apparatus 600 according to an embodiment of the present invention, and FIG. 11 is a scanning electron microscope (SEM) photo of a bone filler grinded by the grinding apparatus 600 of FIG. 10.

[84] The grinding apparatus 600 grinds an outer shape of a cylindrical bone filler in which a micro-pore has been formed through a sintering process and includes a vessel body 610, a cover 640, a grinding plate 620, and an organic solvent 630. The vessel body 610 contains the bone filler to be grinded, the cover 640 seals the vessel body 610, the grinding plate 620 grinds edges of the bone filler using rubbing, and the organic solvent 630 is contained in the vessel body 610 to prevent particles of the bone filler from clashing against one another in a process of grinding the bone filler.

[85] The vessel body 610 must contain the bone filler to be grinded and thus have a space containing the bone filler. The vessel body 610 may be rotated by a driver such as a motor or the like based on an axis.

[86] If the vessel body 610 rotates with containing the bone filler, the grinding plate 620 grinds the edges of the bone filler. For this purpose, the grinding plate 620 includes a metal plate such as a stainless steel plate and diamond particles uniformly distributed on a surface of the metal plate. The grinding plate 620 adheres to an inner wall of the vessel body 610 to grind the edges of the bone filler contained in the vessel body 610.

[87] The organic solvent 630 operates as a cushion that prevents the bone filler contained in the vessel body 610 from receiving an impact due to collisions among the particles of the bone filler. The organic solvent 630 also frequently contacts an outer surface of the bone filler so as to smooth the outer surface of the bone filler. Here, the organic solvent 630 does not dissolve the bone filler and may be a solution heavier than H 0 so that a grinding process is performed when the bone filler is 3-dimensionally distributed in the organic solvent 630. Thus, CH OH may be used as the organic solvent 630, however, the present invention is not limited thereto.

[88] If the bone filler is injected into the grinding apparatus 600 having the above- described structure, and then the grinding apparatus 600 rotates at a predetermined angular velocity, the edges of the bone filler start wearing due to the friction between the bone filler and the diamond particles. As time elapses, the cylindrical bone filler is transformed into a spherical bone filler B in which a macro-pore P and a micro-pore Q are 3-dimensionally formed as shown in FIG. 11. If a bone filler is formed in a spherical shape as described above, the bone filler does not have sharp parts. Thus, if the bone filler is implanted into an organism, an organic cell contacting the implanted bone filler is not stimulated and damaged by the bone filler when the bone filler generates and settles a new bone. Also, since the bone filler does not have the sharp parts, the bone filler does not easily crumble. [89] A method of manufacturing a bone filler, including a method of forming a bone filler, will now be described with reference to FIGS. 12 and 13.

[90] FIG. 12 is a flowchart of a method of manufacturing a bone filler, including a method of forming a bone filler using the forming apparatus 200, according to an embodiment of the present invention, and FIG. 13 is a flowchart of the method of forming the bone filler using the forming apparatus 200 of FIG. 2, according to an embodiment of the present invention.

[91] In operation S210, a calcium phosphate compound, a micro-pore forming agent, and other additives are uniformly mixed using the mixing apparatus 100 to make a bone filler into a slurry state. Here, an amount of the micro-pore forming agent can be adjusted to adjust a number of micro-pores formed in the bone filler in a sintering process that will be described later. Thus, the whole micro-pore rate of the bone filler can be adjusted.

[92] In operation S220, the bone filler in the slurry state is compressed and syringed using the forming apparatus 200 to form a bone filler in which a macro-pore is formed. The formation of the bone filler will now be described in more detail with reference to FIG. 13.

[93] In operation 212, the bone filler in the slurry state is injected into the bone filler containing space 215 of the cylinder 210 of the forming apparatus 200. In operation S214, the bone filler is compressed toward the drain nozzle 213 of the cylinder 210 using the piston 220 of the forming apparatus 200. In operation S216, the bone filler is compressed by the piston 220 to be drained through the output 213a provided at the lower end of the drain nozzle 213 so as to be transformed into a bone filler in which a macro-pore is formed by the macro-pore core 232 provided in the center of the outlet 213a.

[94] Here, a shape and a size of the bone filler are approximately determined depending on a shape and a size of the outlet 213a, and a shape and a size of the macro-pore is determined depending on a shape and a size of the macro-pore core 232. The shapes and sizes of the outlet 213a and the macro-pore core 232 may be modified into various forms. Thus, the bone filler can be adjusted to various shapes and sizes in a process of forming the bone filler. As a result, the whole micro-pore rate of the bone filler can be adjusted.

[95] In operation S230, the formed bone filler is dried for 1 to 2 hours at a temperature between 100⁰C and 200⁰C using the drying apparatus 300. As a result, the viscosity of the bone filler is weakened due to the drying process, and thus the bone filler is made into a cuttable state.

[96] In operation S240, the dried bone filler is cut to a predetermined length. In operation S250, the cut bone filler is sintered. Here, the bone filler is sintered for 1 to 2 hours at a temperature between 1000⁰C and 1200⁰C. In general, a temperature of 1200⁰C or more is required to sinter a calcium phosphate compound. However, if the bone filler is compressed to be formed using the method of forming the bone filler using the forming apparatus 200, the bone filler may be sintered at a temperature between 1000⁰C and 1200⁰C. This results from a property of the sintering temperature of the bone filler that is affected by a compression degree of the bone filler. Therefore, the bone filler is compressed to be formed using a piston in a forming process so as to lower the sintering temperature.

[97] In general, a physical property of a calcium phosphate compound may vary at a temperature of 1200⁰C or more. If a bone filler is manufactured using the forming apparatus 200 of the present invention, the bone filler can be sintered at a temperature lower than 1200⁰C. Thus, a physical property of the bone filler, in particular, a variation possibility of a decomposition speed of the bone filler in an organism can be considerably reduced. If a sintering temperature of 1200⁰C or more is required in a sintering process of the bone filler, a selectable range of the sintering temperature is narrow. Thus, it is difficult to adjust the hardness of the bone filler determined depending on the sintering temperature. If the bone filler is formed and then sintered, the selectable range of the sintering temperature in the sintering process is widened. Thus, the hardness of the bone filler can be easily adjusted.

[98] The bone filler loses viscosity in the sintering process and thus is changed into a solid state so as to have the hardness enough to be implanted into an organism. Also, a micro-pore forming agent uniformly distributed in the bone filler is volatilized, and thus a micro-pore is 3-dimensionally formed throughout the bone filler.

[99] In operation S290, edges of the sintered bone filler are grinded to obtain the bone filler B having a final shape as shown in FIG. 11.

[100] As described above, a bone filler can be manufactured using the forming apparatus

200 of the present invention. Thus, the bone filler can be formed and compressed in a forming process before experiencing a sintering process. As a result, even if a sintering temperature is low, a bone filler having hardness enough to be implanted into an organism can be obtained. Accordingly, the bone filler can be sintered at a lower temperature than in a conventional method of forming a bone filler. Thus, a variation possibility of a physical property of the bone filler made of a calcium phosphate compound in the sintering process can be considerably reduced, and the hardness of the bone filler can be easily adjusted.

[101] In addition, a process of grinding and sifting the bone filler is not required after the bone filler is sintered. Thus, a loss of a material of the bone filler can be considerably reduced, and sharp parts that may stimulate and damage an organic cell are not formed on a surface of the bone filler. [102] Moreover, a size of a macro-pore and a number of micro-pores can be easily adjusted. Thus, the whole micro-pore rate of the bone filler can be effectively adjusted.

[103] While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the following claims. Industrial Applicability

[104] According to the present invention, a bone filler can be formed in a predetermined shape using a process of compressing and draining a bone filler in a slurry state. Thus, a variation possibility of a physical property of the bone filler can be removed in a sintering process, and the hardness of the bone filler can be easily adjusted. Also, an unnecessary loss of a material of the bone filler can be reduced, and sharp parts that may damage an organic cell cannot be formed on a surface of the bone filler.

Claims

[1] An apparatus for forming a bone filler, comprising: a bone filler receptor cell comprising a bone filler containing space and a drain nozzle through which the bone filler is drained; and a compressor draining the bone filler through the drain nozzle.

[2] The apparatus of claim 1, further comprising a macro-pore former combined with the bone filler receptor cell to form a macro-pore in a center of the bone filler.

[3] The apparatus of claim 2, wherein the macro-pore former comprises: a macro-pore core keeping a distance from an outlet of the drain nozzle to be positioned in a center of the outlet; and a macro-pore former body installed in the bone filler receptor cell to support the macro-pore core.

[4] The apparatus of claim 3, wherein a cross-section of the macro-pore former body is smaller than that of the bone filler receptor cell so that the bone filler passes between the bone filler receptor cell and the macro-pore former body.

[5] The apparatus of claim 1, wherein: the bone filler receptor cell is a cylinder comprising an end at which the drain nozzle is provided, and the compressor is a piston that goes up and down in contact with an inner wall of the cylinder.

[6] The apparatus of claim 5, wherein the drain nozzle is a slanting nozzle whichis connected to the end of the cylinder and thus of which diameter is gradually reduced along a longitudinal direction of the cylinder.

[7] The apparatus of claim 5, wherein a packing is combined with a lower end of the piston to seal an interior of the cylinder.

[8] The apparatus of claim 5, wherein: the piston comprises: a piston rod installed in the cylinder to go up and down inside the cylinder and compressing the bone filler; and a handle provided at the piston rod, and the apparatus further comprises: a penetration tube combined with an upper end of the cylinder and through which the piston rod penetrates; an elastic body disposed above the penetration tube; and a penetration tube receptor containing the penetration tube and the elastic body and combined with the cylinder to rotate.

[9] The apparatus of claim 1, wherein the bone filler comprises: at least one of a calcium phosphate compound, calcium sulfate (CaSO ), and calcium carbonate (CaCO ); and a micro-pore forming agent mixed with the calcium phosphate compound to form a micro-pore in the bone filler in a sintering process.

[10] The apparatus of claim 9, wherein the calcium phosphate compound is at least one of tricalcium phosphate (TCP, Ca (PO ) ), tetracalcium phosphate (TeCP, Ca O(PO) ), dicalcium phosphate dihydtate (DCPD, CaHPO (H 0) ), and hydroxy apatite (HA, Ca (PO ) (OH) ).

[11] The apparatus of claim 9, wherein the micro-pore forming agent is at least one of poly methyl meta acrylate (PMMA), starch, and naphthalene ( C H ).

10 o

[12] The apparatus of claim 3, wherein a diameter of the macro-pore is within a range between IOOD and 100OD. [13] A method of forming a bone filler, comprising: injecting a bone filler into a space of a bone filler receptor cell comprising a drain nozzle draining the bone filler; compressing the injected bone filler; and draining the bone filler through the drain nozzle. [14] The method of claim 13, wherein the bone filler is drained through a macro-pore core provided in a center of the drain nozzle to form a macro-pore in a center of the bone filler.