JP2507953B2 - Granules for filling bone voids and bone resorption parts - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention fills bone defects such as bone voids and bone resorption parts, fixes them at the filling points, and generates bone tissue and bone-like tissue. The present invention relates to a granulated material for filling a bone void portion and a bone resorption portion.

<Prior Art> Conventionally, when treatment is required for a bone defect portion and a bone void portion, the shapes of the bone defect portion and the bone void portion are not constant,
Moreover, since it has a complicated shape, for example, a method of using a sintered body processed so as to conform to the shape as a filler has been performed. However, in the method,
In the actual surgery, there is a disadvantage that the filler needs to be further processed according to its shape, the operation time is extended, and a great burden is imposed on the operator and the patient. Therefore, in recent years, various fillers have been proposed in order to solve such problems. For example, granules of bio-ceramics having a simple shape such as a sphere, an amorphous shape, an ellipse, etc. are known. However, the granules of the biomedical ceramics tend to be delayed in the generation of new bone when the granules of a bone defect or the like are filled and then an external force acts on the granules.

On the other hand, recently, a filler made by pouring a slurry in which ceramic powder is mixed with an organic binder and water into a predetermined mold, a filler made by pressing a ceramic raw material powder into a mold and press-molding, and further a ceramic raw material powder and an organic binder. Also, a filler and the like have been developed in which water is wet-kneaded and extruded using a mold and cut to a desired length to form (Japanese Patent Laid-Open No. 58-1441).

However, the above-mentioned filler is industrially difficult to mass-produce, and since the protrusions are quite large, the three-dimensional voids formed when the protrusions intersect with each other are significantly widened, and thus the biocompatibility is high. Although good, it has the drawback of delaying the formation of new bone.

<Problems to be Solved by the Invention> Therefore, an object of the present invention is to form a bone tissue and a bone-like tissue in a particularly short period of time with excellent biocompatibility and no foreign body reaction, and to provide a structure of a bone tissue defect site. Another object of the present invention is to provide a granule for filling a bone void portion and a bone resorption portion, which can quickly restore and restore its function.

Another object of the present invention is to provide a granule for filling a bone void portion and a bone resorption portion, in which individual granules do not move even if they are externally acted upon after filling a bone defect portion.

<Means for Solving the Problems> According to the present invention, a granulated product made of calcium phosphate-based ceramics, the surface of the granulated product is coated with a ceramic powder having the same composition as the calcium phosphate-based ceramics, The ceramic powder is provided with a plurality of protrusions, and the coating of the protrusions protrudes from the adjacent protrusions on the surface of the granulated product when a plurality of the granulated products are filled in the bone voids and the bone resorption parts. There is provided a granule for filling a bone void portion and a bone resorption portion, which is characterized by intersecting with a portion to form a three-dimensional space.

 The present invention will be described in more detail below.

The granules for filling bone voids and bone resorption parts of the present invention are granules of calcium phosphate-based ceramics having a plurality of protrusions on the surface.

Examples of the calcium phosphate-based ceramics that form the granulated material for filling of the present invention include tricalcium phosphate containing alumina and the like, hydroxyapatite, tetracalcium phosphate, oxyapatite, calcium pyrophosphate, fluoroapatite, and one of the hydroxyl groups of hydroxyapatite. Compound, whose part is replaced by fluorine ion,
HPO ₄・ 2H ₂ O) and mixtures thereof, etc., of which the rate of new bone formation is fast, namely tricalcium phosphate, hydroxyapatite, fluoroapatite or tetracalcium phosphate. It is preferable to use one kind or a mixture of two or more kinds selected. Among them, hydroxyapatite is most preferable because it has the fastest new bone formation rate.

In order to produce the filling granulated product of the present invention, it is obtained by coating the surface of a granular material made of calcium phosphate-based ceramics with a powder having the same composition as the granular material and forming a plurality of protrusions on the surface. be able to. The granules are preferably formed into spheres by, for example, a coating granulation method, and the size thereof is preferably in the range of 2.0 to 0.5 mm. Further, the powder needs to have the same composition as the granular material in order to firmly fix it on the surface of the granular material. The particle size of the powder is preferably 150 μm or less, and the particle size of the granulated product coated with powder ends is 10.0 to 1.0 m.
It is preferably in the range of m.

In order to coat the powder on the surface of the granular material, for example, polyvinyl alcohol (hereinafter abbreviated as PVA), polyvinyl acetate, dextrin, gum arabic or the like is sprayed on the granular material, and the powder is preferably coated.
It can be carried out by a method of sufficiently drying at -50 ° C and then firing at 1200-700 ° C. The powder here does not necessarily have to be coded on the entire surface of the granulate, but can also be further coated onto the coated powder. That is, the powder is firmly fixed to the surface of the granular material, the surface of the resulting granular material has a plurality of protrusions, and when filling the bone defect portion and the bone resorption portion, 3 and the protrusion and the protrusion intersect
The powder may be coated on the powder material in any manner as long as the three-dimensional space can be formed.

<Effects of the Invention> The granules for filling the bone void portion and the bone resorption portion of the present invention are formed of calcium phosphate-based ceramics, and thus are excellent in biocompatibility and are provided with a plurality of protrusions on the surface. Since it has excellent stability after filling, and when filling, the protrusions intersect with each other to form a three-dimensional void, so new bone can be rapidly generated in a short time, and bone loss can be easily achieved. The part and the bone resorption part can be repaired and restored.

<Examples> The present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto.

Example 1 A dried product of hydroxyapatite (hereinafter abbreviated as HAP) was pulverized to obtain a granular material having a particle size of 0.6 mm or less and a powder having a particle size of 90 μm or less.

Then, using a pan-type granulator, make 0.6 mm granules,
While spraying a wt% PVA aqueous solution, a powder having a particle size of 90 μm or less was coated, and a protrusion was provided on the surface.
A 2.0 mm grape tuft granulate was formed. Then, it was sufficiently dried at 80 ° C. and baked at 900 ° C. to obtain a granulated material for filling. FIG. 1 shows an enlarged schematic view of the obtained granules 10 for filling a tuft of grapes. As shown in FIG. 1, the surface of the obtained granulated material for filling 10 was provided with a protrusion 11 made of powder.

Next, the obtained granules for filling were filled in the bones of the femurs of rabbits, and after 4 weeks, the tissue was observed. As a result, the generation of new bone was remarkable as if the protrusions of the granules were connected. Admitted.

Example 2 A granulation material for filling was produced in the same manner as in Example 1 except that a granular material of 1.0 to 6.0 mm obtained by pulverizing a dried HAp material was used as the granular material. As shown in FIG. 2, the obtained filling granules were Compay sugar-like filling granules 20 having a particle size of 2.0 to 3.0 mm and provided with protrusions 21 on the surface. It had been.

Next, the obtained granules for filling were filled in the pulp of the femur of the rabbit in the same manner as in Example 1, and the tissue after 4 weeks was observed. As a result, new bone was formed so as to connect the protrusions. Was remarkably recognized.

Comparative Example 1,2 Tetrapot type particle size consisting of HAp by casting shaping
Granules of 3.0 to 2.0 mm (Comparative Example 1) and HAp dried product were crushed to obtain granules sieved at 3.0 to 2.0 mm (Comparative Example 2). Then each granule was calcined at 900 ° C. and then Example 1
In the same manner as above, the intramedullary femurs were each filled with intramedullary bone, and the tissue was observed 4 weeks later. As a result, in each of the granules of Comparative Examples 1 and 2, only a small amount of new bone was found around the intergranular area, and compared with the granules of Examples 1 and 2, the amount of new bone produced was smaller. The amount was remarkably small.

[Brief description of drawings]

FIG. 1 is an enlarged schematic view of the granules for filling a bone void portion and a bone resorption portion produced in Example 1, and FIG. 2 is the granule for filling a bone void portion and a bone resorption portion produced in Example 2. FIG. 10,20 ... Granules for filling, 11,21 ... Projections.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Toyohiko Yamamoto 2270 Yokose, Yokose-cho, Chichibu-gun, Saitama Mitsubishi Mining and Cement Co., Ltd. Ceramics Research Laboratory (56) Reference JP-A-62-224356 (JP, A) Sho 59-171546 (JP, A)

Claims (1)

(57) [Claims] 1. A granulated product made of calcium phosphate-based ceramics, the surface of which is coated with a ceramic powder having the same composition as the calcium phosphate-based ceramics, the ceramic powder having a plurality of protrusions. When the plurality of granules are filled in the bone void portion and the bone resorption portion, the protrusions on the surface of the adjacent granules intersect with each other to form a three-dimensional coating. A granule for filling a bone void portion and a bone resorption portion, which is characterized by forming a space.