COMPOSITE OF HAp / Col FIBER MATERIAL, PRODUCTION METHOD THEREOF, KNITTED FABRIC-LIKE STRUCTURE, BONE PROSTHETIC MATERIAL, AND ORIENTATION CONTROL METHOD OF FIBER MATERIAL

Abstract

To provide a composite of a HAp / Col fiber material and the like capable of individually controlling a region where bone resorption by the osteoclast in an organism is performed, and a region where bone formation by the osteoblast is performed.SOLUTION: A composite of a fiber material containing hydroxyapatite and collagen includes: a first region where the long exterior surfaces of the fiber material extending along the longitudinal direction of the fiber material are aggregated and exposed; and a second region where the edge surfaces in the longitudinal direction of the fiber material are aggregated and exposed. In the first region, the exterior surfaces of the fiber material extend along the prescribed direction.SELECTED DRAWING: Figure 9

Description

[Technical field]

[0001] The present invention relates to a composite of an HAp / Col fiber material and a method for producing the same, a knitted structure, a bone prosthesis material, and a method for controlling the orientation of a fiber material. [Background technology]

[0002] Conventionally, artificial bone substitute materials have been used to repair bone defects in the field of orthopedic surgery.

[0003] Bone tissue maintains bone mass, strength, and elasticity through bone remodeling metabolism, which consists of bone resorption by osteoclasts and bone formation by osteoblasts in the resorption lacunae formed by osteoclasts. For this reason, bone filling materials are required to have excellent biocompatibility and osteoconductivity. In this regard, hydroxyapatite (HAp), an inorganic substance, has excellent bone affinity, and collagen (Col), an organic substance, has the effect of promoting cell adhesion and cell differentiation, so a composite of hydroxyapatite and collagen (HAp / Col composite) is expected to have excellent properties as a bone filling material.

[0004] As techniques relating to HAp / Col composites and methods for producing the same, the techniques of Patent Documents 1 to 4 and Non-Patent Document 1 are known, for example. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 3592920 [Patent Document 2] JP 2003-190271 A [Patent Document 3] Patent No. 4226830 [Patent Document 4] International Publication WO2004 / 041320 [Non-patent literature]

[0006] [Non-Patent Document 1] M.Kikuchi et.al, DOI:10.1016 / S0142-9612(00)00305-7 “Self-organization mechanism in a bone-like hydroxyapatite / collagen nanocomposite synthesized in vitro and its biological reaction in vivo” [Non-Patent Document 2] Taira Sato, Masanori Kikuchi, Mamoru Aizawa, Preparation of Hydroxyapatite / Collagen Injectable Bone Paste with an Anti-Washout Property Utilizing Sodium Alginate. Part 1: Influences of Excess Supplementation of Calcium Compounds, Journal of Materials Science: Materials in Medicine, 28(3), 491-497,DOI:10.1007 / s10856-017-5853-3 (2017) [Non-Patent Document 3] Taira Sato, Yuki Shirosaki, Masaki Nagaya, Yoshinori Asano, Kazuaki Nakano, Hiroshi Nagashima, Mamoru Aizawa, Masanori Kikuchi, Preparation of Anti-Decay Self-Setting Pastes of Hydroxyapatite / Collagen Utilizing (3-Glycidoxypropyl)trimethoxysilane, Journal of Asian Ceramic Societies, 6(4), 322-331, DOI:10.1080 / 21870764.2018.1517712 (2018)) [Summary of the Invention] [Problem to be solved by the invention]

[0007] However, with previous bone filling materials made from HAp / Col composites, it was not possible to separately control the areas in the body where bone resorption occurs by osteoclasts and the areas where bone formation occurs by osteoblasts.

[0008] The present invention has been made in consideration of the above circumstances, and aims to provide a composite of HAp / Col fiber material capable of separately controlling the region in the body where bone resorption is performed by osteoclasts and the region in the body where bone formation is performed by osteoblasts, a method for producing the same, a knitted structure, and a bone prosthetic material. Another aim of the present invention is to provide an orientation control method for orienting the longitudinal direction of a fiber material containing hydroxyapatite and collagen in one direction. [Means for solving the problem]

[0009] In order to solve the above problems, the following composite, knitted structure, bone prosthesis material, method for producing the composite, and method for controlling the orientation of a fiber material are provided. [1] A composite of a fibrous material containing hydroxyapatite and collagen, A first region in which a long outer surface of the fibrous material extending along a longitudinal direction of the fibrous material is collectively exposed; A second region in which the longitudinal end faces of the fiber material are collectively exposed; Including, In the first region, the outer surface of the fibrous material extends along a predetermined direction. Complex. [2] The average fiber length of the fiber material is 60 μm to 2 mm. A complex of the above [1]. [3] In the first region, the outer surface of the fibrous material is oriented in one direction. A complex of [1] or [2] above. [4] Having a laminated structure made of the fiber material, A complex of any one of [1] to [3] above. [5] The thickness in the stacking direction is 5 mm or less; A complex of the above [4]. [6] The fiber material having a length of 60 μm or more is twisted into a twisted yarn. A complex of the above [1]. [7] It is woven by the composite material of [6] above, Knitted structure. [8] The composite of any one of [1] to [6] or the knitted structure of [7] is included. Bone filling material. [9] A method for producing the composite of [1], comprising the steps of: A precursor of a fibrous material containing hydroxyapatite and collagen is uniaxially pressed to obtain a composite in which the fibrous material is oriented in a predetermined direction. A method for producing the composite.

[10] Uniaxially pressurizing the composite so that the thickness of the composite is 5 mm or less. A method for producing the composite of [9] above.

[11] A method for producing the composite of [1], comprising the steps of: The method includes twisting thread-like fibrous materials containing hydroxyapatite and collagen to obtain a twisted thread-like composite. A method for producing the composite.

[12] A method for producing the composite of [1], comprising the steps of: The method includes extruding a paste of fibrous material containing hydroxyapatite and collagen through a tube having a diameter of 2 mm or less. A method for producing the composite.

[13] A precursor of a fibrous material containing hydroxyapatite and collagen is uniaxially pressurized to orient the longitudinal direction of the fibrous material in one direction. A method for controlling the orientation of fibrous materials. Effect of the Invention

[0010] The composite, knitted structure, and bone filling material of the present invention can individually control the region in the body where bone resorption occurs by osteoclasts and the region where bone formation occurs by osteoblasts. The composite manufacturing method of the present invention can manufacture a composite having the above characteristics. The fiber material orientation control method of the present invention can orient the longitudinal direction of the fiber material in one direction. [Brief description of the drawings]

[0011] [Figure 1] FIG. 2 is a schematic diagram illustrating the first region (the outer longitudinal surface of the HAp / Col fibrous material) of the composite of the first embodiment. [Diagram 2] FIG. 2 is a schematic diagram illustrating the second region (the longitudinal end surface of the HAp / Col fibrous material) of the composite of the first embodiment. [Diagram 3] FIG. 2 is a schematic diagram showing a first region of a modified example of the first embodiment of the composite of the present invention. [Figure 4] FIG. 2 is a schematic diagram illustrating a second embodiment of the composite of the present invention. [Diagram 5] FIG. 1 is a schematic diagram illustrating a third embodiment of the composite of the present invention. [Figure 6] FIG. 11 is a schematic diagram showing a modified example of the composite body of the third embodiment. [Figure 7] FIG. 1 is a schematic diagram illustrating one embodiment of a knitted structure of the present invention. [Figure 8] These are micro-CT images of the implantation site of the HAp / Col fibrous material composite 1.5, 3, 5, 7, 14, and 28 days after implantation. CB in the figure indicates cortical bone. [Figure 9] The figure shows the observation site of the embedded composite. (1) shows the surface where the end faces of the HAp / Col fibrous material are mostly exposed (surface parallel to the compression direction), and (2) shows the surface where the longitudinal direction of the HAp / Col fibrous material is mainly exposed (surface perpendicular to the compression direction). [Figure 10]This is a tissue image of the surface (parallel to the compression direction) where the end face of the HAp / Col fibrous material is largely exposed 14 days after implantation. A large number of osteoclasts (oc) have accumulated on the end face of the HAp / Col fibrous material. [Figure 11] This is a tissue image of the surface (parallel to the compression direction) where the end faces of the HAp / Col fibrous material are largely exposed 28 days after implantation. Bone (arrowheads) has formed on the end faces of the absorbed Hap / Col fibrous material. Additionally, in the area where the longitudinal direction of the HAp / Col fibrous material is exposed, new bone (arrows) has formed on the fibers. The symbol oc in the figure indicates osteoclasts. [Figure 12] This is a histological image of the surface (perpendicular to the compression direction) of the HAp / Col fiber material 14 days after implantation, where the longitudinal direction is mainly observed. Bone formation has occurred on the fibers, and osteoblasts (ob) are observed on the newly formed bone. On the other hand, osteoclasts are hardly observed. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, embodiments of the composite and the method for producing the composite of the present invention will be described.

[0013] First Embodiment (Complex) Fig. 1 is a schematic diagram illustrating a first region of the complex of the first embodiment, Fig. 2 is a schematic diagram illustrating a second region of the complex of the first embodiment, and Fig. 3 is a schematic diagram showing the first region of a modified example of the first embodiment of the complex of the present invention.

[0014] The composite 1 of the present invention is a composite 1 of a fibrous material containing hydroxyapatite and collagen (hereinafter referred to as "HAp / Col fiber material").

[0015] The average fiber length of the HAp / Col fiber material 2 is not particularly limited, but is preferably 60 μm or more, more preferably 1 mm or more, and even more preferably 3 mm or more. The upper limit of the average fiber length of the HAp / Col fiber is not particularly limited, but in practice, it is, for example, 10 cm or less. The "average fiber length" refers to the average length (mean) of the fibers comprising the complex, and can be measured by a known device or visually. When the average fiber length of the HAp / Col fiber material 2 is within this range, the region in which bone formation by osteoblasts takes place can be stably controlled.

[0016] The diameter of the HAp / Col fiber material 2 is not particularly limited, but is preferably 0.1 μm or more, and more preferably 0.5 μm or more. When the diameter of the HAp / Col fiber material 2 is within this range, the region in which bone resorption by osteoclasts occurs can be stably controlled.

[0017] 1 and 2, the composite 1 includes a first region T1 in which the long outer surfaces of the HAp / Col fibrous material 2 extending along the longitudinal direction of the HAp / Col fibrous material 2 are collectively exposed, and a second region T2 in which the longitudinal end faces of the HAp / Col fibrous material 2 are collectively exposed. In the first region T1 of the composite 1, the outer surface of the HAp / Col fibrous material 2 extends along a predetermined direction.

[0018] Specifically, in the first region T1 of the composite 1 of this embodiment, the outer surfaces of the HAp / Col fibrous material 2 in the longitudinal direction are exposed in a state of being oriented in one direction (arrow X direction). In the first region T1 of the composite 1 of this embodiment, the HAp / Col fibrous material 2 does not have to be aligned strictly in one direction. That is, the composite 1 of this embodiment also includes a form in which the longitudinal direction of the HAp / Col fibrous material 2 partially or entirely crosses while the outer surfaces of the HAp / Col fibrous material 2 in the longitudinal direction extend in a predetermined direction (arrow X direction), as shown in FIG. 3. For example, in the form shown in FIG. 3, the longitudinal direction of the HAp / Col fibrous material 2 may be inclined by about 1 to 30° with respect to the predetermined direction (arrow X direction).

[0019] As illustrated in Fig. 1 to Fig. 3, in the second region T2 of the composite 1 of this embodiment, the longitudinal end faces of the HAp / Col fibrous material 2 are collectively exposed. As illustrated in Fig. 1 and Fig. 2, the positions of the exposed longitudinal end faces of each of the fibrous materials may be shifted in the direction of the arrow X. In other words, in the second region T2 of the composite 1 of this embodiment, the longitudinal end faces of each of the HAp / Col fibrous materials 2 may be on the same plane perpendicular to the direction of the arrow X (on the same plane including the direction of the arrow Y), or may not be on the same plane perpendicular to the direction of the arrow X (on the same plane including the direction of the arrow Y).

[0020] As shown in Fig. 2, the composite 1 of this embodiment has a layered structure made of HAp / Col fibrous material 2. That is, the composite 1 of this embodiment has a layered structure (Fig. 2) in which the structure of the HAp / Col fibrous material 2 exposed as the first region T1 (Fig. 1) is continuous in the thickness direction (arrow Z direction).

[0021] The composite 1 of this embodiment preferably has a thickness (length in the direction of arrow Z) of 5 mm or less. When the thickness of the composite 1 is in this range, in the first region T1, the outer surface in the longitudinal direction of the HAp / Col fibrous material 2 is likely to be oriented in one direction (direction of arrow X).

[0022] When the composite 1 of this embodiment is embedded in bone tissue in a living body, osteoconduction by osteoblasts occurs in the first region T1 of the composite 1, while bone resorption by osteoclasts hardly occurs. This phenomenon is caused by the orientation of the HAp / Col fibrous material 2 in the first region T1 of the composite 1. Note that in the composite 1 of a conventional HAp / Col fibrous material, the HAp / Col fibrous material is randomly oriented, and in this case, bone resorption of HAp / Col by osteoclasts occurs on the randomly oriented surface.

[0023] Furthermore, in the second region T2 of the complex 1, osteoclasts adhere to the end faces in the longitudinal direction of the HAp / Col fibrous material, and the HAp / Col fibrous material is absorbed. In the second region T2, bone is formed in the absorption cavity a little later. Furthermore, in the second region T2 of the complex 1, for example, when the laminated structure peels off due to swelling and the outer surface of the longitudinal direction of the HAp / Col fibrous material is exposed, osteoconduction by osteoblasts is observed in the exposed part independently of osteoclasts. That is, according to the complex 1 of this embodiment, it is possible to individually control the region (first region T1) where bone formation by osteoblasts occurs and the region (second region T2) where bone absorption by osteoclasts occurs. In addition, according to the complex 1 of this embodiment, it is also possible to realize a material that delays absorption by osteoclasts and induces only osteoconduction early, enabling the regeneration of large bone defects without the aid of drugs or the like.

[0024] (Method of Manufacturing the Composite) As a method for producing the complex 1 of the present invention, the methods described in, for example, Patent Documents 1-4 and Non-Patent Document 1 can be considered. Specifically, the following methods are exemplified.

[0025] The HAp / Col fiber material 2 can be produced using at least three components as starting materials: collagen, phosphate (aqueous solution), and calcium salt (aqueous solution). In the present invention, phosphate includes phosphoric acid, and calcium salt includes calcium hydroxide, although they are not strictly classified as "salts." In the production of the HAp / Col fiber material 2, in addition to the essential components calcium salt, phosphate, and collagen, other components can also be added within a range that does not impair the purpose and effect of the present invention. Examples of such components include inorganic salts such as Sr, Mg, and CO3, organic substances such as citric acid and phospholipids, and drugs such as bone morphogenetic proteins.

[0026] Collagen is not particularly limited in species, tissue site, age, etc. of animals used as a starting material, and any collagen can be used. Generally, collagen obtained from the skin, bone, cartilage, tendon, organ, etc. of mammals (e.g., cows, pigs, horses, rabbits, mice, etc.) or birds (e.g., chickens, etc.) is used. Collagen-like proteins obtained from the skin, bone, cartilage, fins, scales, organs, etc. of fish (e.g., cod, flounder, plaice, salmon, trout, tuna, mackerel, sea bream, sardine, shark, etc.) may also be used as a starting material. Alternatively, collagen obtained by gene recombination technology, rather than extraction from animal tissue, may also be used. Furthermore, collagen may be used after appropriate chemical modification of the amino acid residues of collagen protein, such as acetylation, succination, maleylation, phthalation, benzoylation, esterification, amidation, guanidination, etc. Examples of methods for preparing collagen include methods in which collagen is extracted from the starting material with a neutral buffer solution or a dilute acid such as hydrochloric acid, acetic acid, or citric acid.

[0027] The phosphate source of the aqueous phosphate solution includes disodium hydrogen phosphate, sodium dihydrogen phosphate, dipotassium hydrogen phosphate, potassium dihydrogen phosphate, phosphoric acid, etc. The aqueous phosphate solution can dissolve the above-mentioned collagen and be subjected to the reaction.

[0028] Examples of calcium sources for the calcium salt aqueous solution include calcium carbonate, calcium acetate, calcium hydroxide, etc. The calcium salt aqueous solution may be a suspension so long as it is in a homogeneous state, and for example, a suspension of calcium hydroxide obtained by calcining calcium carbonate and then pulverizing it in a mortar or the like to obtain calcium hydroxide and adding water thereto can be suitably used.

[0029] In producing the HAp / Col fiber material 2, the calcium salt aqueous solution and the collagen-containing phosphate aqueous solution can be dropped simultaneously into a reaction vessel. Here, "simultaneously" does not mean only dropping at the exact same time, but also includes dropping small amounts (about 0.01 to 5 ml) alternately. Both solutions may be dropped continuously or intermittently as long as they are dropped simultaneously. The length of the HAp / Col fiber to be synthesized can be controlled by the dropping conditions. The dropping speed is preferably about 5 to 30 ml / min, and the reaction solution is preferably stirred at about 10 to 200 rpm. After dropping, the dispersion of the HAp / Col fiber material 2 can be freeze-dried.

[0030] In the production of the HAp / Col fiber material 2, it is preferable to maintain the calcium ion concentration in the reaction vessel at 3.75 mM or less and the phosphate ion concentration at 2.25 mM or less. Furthermore, it is more preferable to maintain the calcium ion concentration at 2.5 mM and the phosphate ion concentration at 1.5 mM or less, since it is possible to obtain a composite 1 having an average fiber length of 1 mm or more.

[0031] Furthermore, the hydroxyapatite and collagen produced in the reaction vessel are present in a weight ratio of 1:1 to 9:1, preferably 60:40 to 80:20.

[0032] In the production of the HAp / Col fiber material 2, the calcium ion concentration and phosphate ion concentration in the reaction vessel can be maintained within a desired range by controlling the speed of feeding the calcium salt aqueous solution and the collagen-containing phosphate aqueous solution to the reaction vessel and / or the starting concentration of the calcium salt aqueous solution and the collagen-containing phosphate aqueous solution. Here, the "starting concentration" refers to the individually adjusted concentration of each component (such as the calcium salt aqueous solution and the collagen-containing phosphate aqueous solution) before being fed to the reaction vessel. In addition, the "feeding speed" refers to the amount of each reaction solution delivered per unit time to the reaction vessel. The setting of the feeding speed can be easily achieved, for example, by using a commercially available tube pump.

[0033] For example, when the weight ratio of the generated hydroxyapatite to collagen is maintained at 60:40 to 80:20, the concentration of the calcium salt aqueous solution at the starting stage is 400 mM or less, preferably in the range of 50 to 200 mM, when the average liquid delivery speed of the calcium salt aqueous solution is set to 5 to 30 mM / min. The concentration of the collagen-containing phosphoric acid aqueous solution is 120 mM or less, preferably in the range of 15 to 96 mM. The "average liquid delivery speed" refers to the average amount of liquid delivered to the reaction vessel per minute, taking into account the on / off control of the pump, etc.

[0034] The ratio of the collagen-containing phosphoric acid aqueous solution to the calcium salt aqueous solution is preferably within the range of 3:1 to 1:3.

[0035] It is desirable to dropwise add the reaction solution so that the pH is in the range of 7 to 11 and the range of change is within 1.

[0036] In the production of the HAp / Col fibrous material 2, the temperature of the reaction solution is preferably maintained at 35°C to 40°C.

[0037] Crosslinking treatment can also be performed on the HAp / Col fiber material 2. Any method, such as thermal crosslinking, chemical crosslinking using a crosslinking agent or condensation agent, or physical crosslinking using gamma rays, ultraviolet rays, thermal dehydration, electron beams, etc., may be used. In the case of thermal crosslinking, the material with the coating layer sufficiently dried is vacuum heated at a temperature of, for example, about 120°C for 24 hours to crosslink the collagen chains and strengthen the coating. Examples of chemical crosslinking agents include aldehyde-based crosslinking agents such as glutaraldehyde and formaldehyde; isocyanate-based crosslinking agents such as hexamethylene diisocyanate; carbozide-based crosslinking agents such as 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride; polyepoxy-based crosslinking agents such as ethylene glycol diethyl ether; and transglutaminase. The amount of these crosslinking agents used is preferably about 10 μmol to 10 mmol per 1 g of collagen.

[0038] Although the crosslinking may be performed at any part between collagens, it is particularly preferable to crosslink a carboxyl group with a hydroxyl group, a carboxyl group with an ε-amino group, or between ε-amino groups. It is preferable to introduce crosslinks to at least 1% of the reactive functional groups, and more preferably to introduce crosslinks to 5% or more.

[0039] The method for producing the complex 1 of this embodiment may include known steps such as a solution preparation step and a freeze-drying step in addition to the steps described above.

[0040] The method for producing the composite 1 of this embodiment includes a pressurizing step in which a precursor (assembly) made of the HAp / Col fiber material 2 produced by the above-mentioned method is uniaxially pressurized to obtain the composite 1 in which the fiber material is oriented in a predetermined direction. With this composite 1, it is possible to individually control the region (first region T1) where bone formation by osteoblasts occurs and the region (second region T2) where bone resorption by osteoclasts occurs.

[0041] When the synthesized HAp / Col fibrous material is molded by uniaxial pressure and compression dehydration, a composite 1 having a laminated structure in which the longitudinal direction of the HAp / Col fibrous material is oriented in the direction perpendicular to the compression direction (the direction of the arrow X in Fig. 1) can be obtained, as shown in Fig. 1. In other words, the longitudinal end face of the HAp / Col fibrous material is a surface parallel to the compression direction (the direction of the arrow Z in Fig. 2).

[0042] The conditions for the pressurizing step (uniaxial pressurizing) are not particularly limited and can be appropriately set depending on the composition and crosslinking of the HAp / Col fiber material. For example, the temperature and pressure in the uniaxial pressurizing can be set in consideration of the amount of water released from the composite 1. Specifically, the temperature during the uniaxial pressurizing is preferably 0°C or higher and 30°C or lower, and more preferably 4°C or higher and 25°C or lower. The pressure during the uniaxial pressurizing is preferably 5 MPa or higher and 80 MPa or lower, and more preferably 9 MPa or higher and 30 MPa or lower.

[0043] It is also preferable to compress the HAp / Col fibrous material to a thickness of 5 mm or less by uniaxial compression. By compressing the composite 1 to a thickness of 5 mm or less, the HAp / Col fibrous material can be oriented in a predetermined direction even inside the composite 1.

[0044] Furthermore, the manufacturing method of the composite 1 of this embodiment may include a step of cutting the HAp / Col fibrous material at an appropriate position in a plane perpendicular to the X-direction. This allows the end face of the HAp / Col fibrous material to be exposed on the cut surface to form the second region T2, making it possible to easily adjust the extent of the region (first region T1) where bone formation by osteoblasts occurs and the position of the region (second region T2) where bone resorption by osteoclasts occurs.

[0045] <Second embodiment> Hereinafter, a second embodiment of the complex of the present invention will be described, but a part of the description of the contents common to the first embodiment will be omitted. Fig. 4 is a schematic diagram illustrating the second embodiment of the complex of the present invention.

[0046] (Composite and its manufacturing method) 4, the composite 1 includes a first region T1 in which the long outer surfaces of the HAp / Col fibrous material 2 extending along the longitudinal direction of the HAp / Col fibrous material are collectively exposed, and a second region T2 in which the longitudinal end faces of the HAp / Col fibrous material 2 are collectively exposed. In the first region T1 of the composite 1, the outer surface of the HAp / Col fibrous material 2 extends along a predetermined direction.

[0047] Specifically, in the first region T1 of the composite 1 of this embodiment, the outer surfaces in the longitudinal direction of the long HAp / Col fibrous materials 2 are exposed and collected in a state of being oriented in one direction (the direction of the arrow X).

[0048] The composite 1 of this embodiment can be produced by extruding a paste containing HAp / Col fibrous material through a tube with a diameter of 2 mm or less to a desired length. The HAp / Col fibrous material extruded to a desired length can be arranged in multiple rows in the direction of the arrow Y. This makes it possible to produce a composite 1 in which the outer longitudinal surface of the HAp / Col fibrous material extends in one direction (the direction of the arrow X). Also in this composite 1, the longitudinal end faces of the HAp / Col fibrous material 2 are exposed and gather to form the second region T2. ​​The composite 1 may also have a structure in which the extruded HAp / Col fibrous material is laminated.

[0049] A paste containing HAp / Col fiber material can be prepared, for example, by kneading unpulverized HAp / Col fiber with a liquid (such as an aqueous alginic acid solution or an aqueous (3-glycidyloxypropyl)trimethoxysilane (GPTMS) solution) in a mass ratio of HAp / Col fiber to liquid (HAp / Col fiber:liquid) in the range of 1:10 to 3:2. In addition, when using pulverized HAp / Col fiber, a paste containing HAp / Col fiber material can be prepared by referring to the following Non-Patent Documents 2 and 3. (Non-Patent Document 2) Taira Sato, Masanori Kikuchi, Mamoru Aizawa, Preparation of Hydroxyapatite / Collagen Injectable Bone Paste with an Anti-Washout Property Utilizing Sodium Alginate. Part 1: Influences of Excess Supplementation of Calcium Compounds, Journal of Materials Science: Materials in Medicine, 28(3), 491-497,DOI:10.1007 / s10856-017-5853-3 (2017) (Non-Patent Document 3) Taira Sato, Yuki Shirosaki, Masaki Nagaya, Yoshinori Asano, Kazuaki Nakano, Hiroshi Nagashima, Mamoru Aizawa, Masanori Kikuchi, Preparation of Anti-Decay Self-Setting Pastes of Hydroxyapatite / Collagen Utilizing (3-Glycidoxypropyl)trimethoxysilane, Journal of Asian Ceramic Societies, 6(4), 322-331, DOI:10.1080 / 21870764.2018.1517712 (2018))

[0050] Furthermore, the manufacturing method of the composite 1 of this embodiment can include, for example, constructing a three-dimensional structure consisting of a composite of HAp / Col fiber material by extruding a paste containing HAp / Col fiber material using an extrusion-type three-dimensional printer.

[0051] In the composite 1 of this embodiment, when the composite 1 is embedded in bone tissue in a living body, in the first region T1 of the composite 1, osteoconduction by osteoblasts occurs, while bone resorption by osteoclasts hardly occurs. Furthermore, in the second region T2 of the composite 1, osteoclasts adhere to the end face in the longitudinal direction of the HAp / Col fibrous material, and the HAp / Col fibrous material is absorbed. In addition, in the composite 1 of this embodiment, by setting the diameter of the tube used for extrusion molding to 2 mm or less, osteoclasts can be stably adhered to the end face (second region T2) in the longitudinal direction of the composite 1. That is, according to the composite 1 of this embodiment, the region (first region T1) where bone formation by osteoblasts occurs and the region (second region T2) where bone resorption by osteoclasts occurs can be individually controlled. In addition, according to the composite 1 of this embodiment, a material that delays resorption by osteoclasts and induces only osteoconduction at an early stage, enabling the regeneration of large bone defects, can be realized without the aid of drugs or the like.

[0052] Furthermore, according to the manufacturing method of the complex 1 of this embodiment, the length of the complex 1 in the extrusion direction (direction of the arrow X) can be easily adjusted, and therefore the range of the region (first region T1) where bone formation by osteoblasts takes place can be easily adjusted.

[0053] <Third embodiment> Hereinafter, a third embodiment of the complex of the present invention will be described, but a part of the description of the contents common to the first embodiment will be omitted. Fig. 5 is a schematic diagram illustrating the third embodiment of the complex of the present invention.

[0054] (Composite and its manufacturing method, knitted structure) 5, the composite 1 of this embodiment includes a first region T1 in which the long outer surfaces of the HAp / Col fibrous material 2 extending along the longitudinal direction of the HAp / Col fibrous material 2 are collectively exposed, and a second region T2 in which the longitudinal end faces of the HAp / Col fibrous material 2 are collectively exposed. In the first region T1 of the composite 1, the outer surface of the HAp / Col fibrous material 2 extends along a predetermined direction (the direction of the arrow X).

[0055] Specifically, the composite 1 of this embodiment is in the form of a twisted yarn in which two or more thread-like HAp / Col fibrous materials 2 each having a length of 60 μm or more are twisted together. Fig. 5 shows an example of a twisted yarn-like composite 1 composed of two HAp / Col fibrous materials 2A and 2B. In the composite 1 of this embodiment, the first region T1 is formed such that the long outer surfaces of the two HAp / Col fibrous materials 2A and 2B are exposed over the entire circumferential area of ​​the twisted yarn.

[0056] In a preferred example of the method for producing the composite 1 of this embodiment, for example, short HAp / Col fiber materials are twisted together to obtain a first thread-like fiber. Then, the first thread-like fiber is further twisted (spun) to obtain a second thread-like fiber (twisted composite). The length of the first thread-like fiber depends on the amount of the HAp / Col fiber material used as the material, and is, for example, 60 μm or more. In addition, the length of the second thread-like fiber (twisted composite) can be controlled to a desired length. By obtaining the second thread-like fiber from the first thread-like fiber, the thickness of the second thread-like fiber can be controlled.

[0057] The method for twisting the thread-like HAp / Col fiber material 2 is not particularly limited, and any method conventionally known in the field of fiber processing can be appropriately adopted.

[0058] The method for producing the composite 1 of this embodiment may also include a carding step for removing impurities and aligning the fibers in a certain direction.

[0059] Fig. 6 is a schematic diagram showing a modified example of the composite of the third embodiment. As shown in Fig. 6, for example, a twisted composite 1 can be produced by winding HAp / Col fiber materials 2A and 2B around a base thread C (such as a bioabsorbable suture thread). In this example, the outer surfaces extending along the longitudinal direction of the HAp / Col fiber materials 2A and 2B constituting the twisted composite 1 are also exposed in a collective manner. In addition, the outer surfaces in the longitudinal direction of the HAp / Col fiber materials 2A and 2B extend along the direction of the arrow X. When the twisted composite 1 includes the base thread C, the handling properties can be improved.

[0060] Furthermore, a two-dimensional or three-dimensional knitted structure can be manufactured by knitting the twisted yarn-like composite 1 of this embodiment. Fig. 7 is a schematic diagram illustrating one embodiment of the knitted structure of the present invention.

[0061] 7, for example, twisted yarn composites 1A of a desired length are arranged in a plurality of rows with their longitudinal directions parallel to the direction of arrow X, and another twisted yarn composite 1B is knitted in a direction (arrow Y direction) perpendicular to the direction of arrow X, to obtain a knitted structure W. In the embodiment illustrated in Fig. 7, a first region T1 is formed by the outer surfaces in the longitudinal direction of the twisted yarn composites 1A and 1B, and a second region T2 is formed by the end portion in the longitudinal direction of the twisted yarn composite 1A.

[0062] In the case of the composite 1 or the knitted structure W of this embodiment, when the composite 1 is embedded in bone tissue in a living body, in the first region T1 of the composite 1, osteoconduction by osteoblasts occurs, while bone resorption by osteoclasts hardly occurs. Furthermore, in the second region T2 of the composite 1, osteoclasts adhere to the end faces of the HAp / Col fibrous material in the longitudinal direction, and the HAp / Col fibrous material is resorbed. That is, according to the composite 1 of this embodiment, the region where bone formation by osteoblasts occurs (first region T1) and the region where bone resorption by osteoclasts occurs (second region T2) can be individually controlled. Furthermore, according to the composite 1 of this embodiment, it is possible to realize a material that can delay resorption by osteoclasts and induce only osteoconduction at an early stage, thereby enabling the regeneration of large bone defects without the aid of drugs or the like.

[0063] <Bone replacement material> The bone filling material of the present invention contains the above-mentioned complex 1 or knitted structure W of the present invention, and can individually control the region where bone formation by osteoblasts occurs (first region) and the region where bone resorption by osteoclasts occurs (second region T2). In addition, the bone filling material of the present invention can delay resorption by osteoclasts and induce only osteoconduction early, thereby realizing a material that enables regeneration of large bone defects without the aid of drugs, etc. The bone filling material of the present invention can also contain other conventionally known components.

[0064] The composite and its manufacturing method, knitted structure, and method for controlling the orientation of a fiber material of the present invention are not limited to the above-described embodiments. EXAMPLES

[0065] The complex of the present invention and its production method will be described below with reference to examples. However, the complex of the present invention and its production method are not limited to the following examples.

[0066] <Preparation of Complex> The HAp / Col fiber material was prepared by dropping a 100 mM calcium hydroxide suspension and a 30 mM phosphoric acid aqueous solution containing collagen at an average dropping rate of 15 mL / min. The material was used as a precursor of the HAp / Col fiber material.

[0067] A dense composite (3 mm thick) was produced from this precursor of HAp / Col fiber material by uniaxial pressing using a dehydration mold. This was then punched out with a biopsy trepan to a diameter of 1.5-2 mm to form a cylindrical shape with a height of 3 mm. The molded composite is an anisotropic dense body in which the end faces of the HAp / Col fiber are exposed on the cylindrical end faces, and the longitudinal direction of the HAp / Col fiber material is largely exposed on the cylindrical outer surface. Conventional HAp / Col fiber material composites are often dehydrated by cold isostatic pressing after creating a dehydrated molded body with a thickness of about 5 cm or more. In this case, the HAp / Col fiber material is not sufficiently oriented and laminated, and is arranged almost randomly.

[0068] A cavity of 1.5-2 mm in diameter was formed in the cortical bone of the proximal medial surface of the tibia of 10-week-old male Wistar rats, and a cylindrical composite of the above-mentioned HAp / Col fiber material was embedded. The rats were euthanized 1.5, 3, 5, 7, 14, and 28 days after embedding, and the tibia was extracted. After micro-CT imaging, the specimens were decalcified with EDTA solution and embedded in paraffin in the usual manner, and then observed by hematoxylin-eosin (HE) staining, tartrate-resistant acid phosphatase (TRAP) staining (osteoclasts), and alkaline phosphatase (ALP) immunohistochemical staining (osteoblasts).

[0069] Micro-CT images revealed that bone was formed around the composite of HAp / Col fiber material that was implanted early after surgery, and that the composite and the host bone gradually integrated in the cortical bone area and were replaced by cortical bone, while in the bone marrow area, HAp / Col was absorbed, including the bone that had formed around it (Figure 8). These results were not significantly different from previous reports.

[0070] In the histologically stained specimens, (1) the surface where the end faces of the HAp / Col fibrous material were largely exposed (surface parallel to the compression direction) and (2) the outer surface where the longitudinal direction of the HAp / Col fibrous material was mainly revealed (surface extending perpendicular to the compression direction) (Figure 9) were observed, and the following findings were obtained.

[0071] (1) A surface where the longitudinal end faces of the HAp / Col fibrous material are mostly exposed (a surface parallel to the compression direction) A large number of osteoclasts were accumulated on the longitudinal end faces of the HAp / Col fibrous material, and resorption of the HAp / Col fibrous material by TRAP-positive osteoclasts occurred (Fig. 10). After that, bone formation by osteoblasts was induced (Fig. 11). Furthermore, in areas where the laminated structure peeled off and the longitudinal direction (long axis direction) of the HAp / Col fibers was exposed, new bone was formed on the fibers (Fig. 11), and this is thought to be bone formation independent of bone resorption by osteoclasts.

[0072] (2) A surface where the longitudinal direction of the HAp / Col fibrous material is predominant (a surface perpendicular to the compression direction) Osteoblasts were established on the outer surface of the HAp / Col fibrous material in the longitudinal direction, and bone formation occurred (Figure 12). Few osteoclasts were observed on the outer surface of the HAp / Col fibrous material in the longitudinal direction, suggesting that modeling occurred in which osteoblasts form bone independently of bone resorption by osteoclasts.

[0073] From the above results, it was confirmed that by controlling the surface (first region) where the longitudinal outer surface of the HAp / Col fibrous material is exposed and the surface (second region) where the longitudinal end surface of the HAp / Col fibrous material is exposed, it is possible to individually control the region in the body where bone resorption by osteoclasts occurs and the region where bone formation by osteoblasts occurs. [Explanation of symbols]

[0074] 1. Complex 2. HAp / Col fiber material T1 1st area T2 2nd area W knitted structure

Claims

1. A composite of a fibrous material containing hydroxyapatite and collagen, A first region in which an elongated outer surface of the fibrous material extending along a longitudinal direction of the fibrous material is collectively exposed; A second region in which end faces of the fiber material in the longitudinal direction are collectively exposed; Including, In the first region, the outer surface of the fibrous material extends along a predetermined direction. Complex.

2. The average fiber length of the fiber material is 60 μm to 2 mm. The conjugate of claim 1.

3. In the first region, the outer surface of the fibrous material is oriented in one direction. The conjugate of claim 1 or 2.

4. The fiber material has a laminated structure. A complex according to any one of claims 1 to 3.

5. The thickness in the lamination direction is 5 mm or less. The complex of claim 4.

6. The fiber material having a length of 60 μm or more is twisted into a twisted yarn. The conjugate of claim 1.

7. The composite of claim 6 is interwoven. Knitted structure.

8. The composite of any one of claims 1 to 6 or the knitted structure of claim 7, Bone filling material.

9. A method for producing the composite of claim 1, comprising the steps of: A precursor of a fibrous material containing hydroxyapatite and collagen is uniaxially pressed to obtain a composite in which the fibrous material is oriented in a predetermined direction. A method for producing the composite.

10. The composite is uniaxially pressed so that the thickness of the composite is 5 mm or less. A method for producing the composite of claim 9.

11. A method for producing the composite of claim 1, comprising the steps of: The method includes twisting thread-like fiber materials containing hydroxyapatite and collagen to obtain a twisted thread-like composite. A method for producing the composite.

12. A method for producing the composite of claim 1, comprising the steps of: The method includes extruding a paste of a fibrous material containing hydroxyapatite and collagen through a tube having a diameter of 2 mm or less. A method for producing the composite.

13. A precursor made of a fibrous material containing hydroxyapatite and collagen is uniaxially pressurized to orient the longitudinal direction of the fibrous material in one direction. A method for controlling the orientation of fibrous materials.

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