JPH07114803B2 - Method for producing substitute material for biological hard tissue repair - Google Patents

Description

The present invention relates to an alternative material for repairing a living body or tissue for artificially prosthesing a bone defect portion, a void portion, or the like.

Recently, it can be safely implanted in the living body as a substitute material for the restoration of living hard tissues such as teeth and teeth that have been lost due to traffic accidents, caries, severe periodontal disease, surgery, etc. It is desired to develop an artificial material that has good workability, sufficient durability, and clinically good workability.

Conventionally, various alloys and polymer materials have been used as this kind of material, but there is a risk of elution and corrosion of metal ions, and the compatibility with bone tissue cannot be said to be good, so that it is suitable for long-term implantation. There were few things I could bear. In recent years, as a material that has improved such defects, hydroxyapatite <Ca ₁₀ (po ₄ ) ₆ which is an inorganic component of ceramics and bones and teeth is used.
(OH) ₂ > has attracted attention, and in the former, its chemical composition and structure are completely different from the hard tissue of the living body, and it cannot be said that it is necessarily a good alternative material for repairing the hard tissue of the living body. Met. Further, in the latter, the affinity with living tissue is relatively good, but the use site is limited and the application is limited.

When making a molded body from any of these materials, since it is manufactured in a factory at a high temperature and high pressure facility, only the ready-made form can be clinically used. There are cases such as cutting off even large parts,
It was extremely inconvenient.

In view of the above, the present inventors have earnestly studied, tricalcium phosphate which is a precursor of hydroxyapatite, calcium phosphate compounds shown in tetracalcium phosphate, water,
It was found that a molded product having good physical properties and excellent biocompatibility can be easily obtained by baking a temporary coagulation cured product containing a curing agent such as an inorganic acid, an organic acid, and an organic compound. The present invention has been reached.

The raw material and manufacturing method of the present invention will be described below.

Calcium Phosphate Compound In the present invention, “calcium phosphate compound” means α-Ca ₃
It is represented by (PO ₄ ) ₃ . Alpha-type tricalcium phosphate, a compound represented by tetracalcium phosphate represented by Ca ₄ P ₂ O ₉ , CaCO ₃ , CaO, and Ca as calcium sources.
(OH) ₂ , P ₂ O ₅ , H ₃ PO ₄ , NH ₄ H ₂ PO ₄ , (N
H ₄ ) ₂ HPO ₄ and C containing both calcium and phosphoric acid
It is represented by α-Ca ₃ (PO ₄ ) ₂ prepared by a conventional method using aHPO ₄ , Ca (H ₂ PO ₄ ) _{2, and the} like. The production method is not particularly limited, but α-Ca ₃ (PO ₄ ) synthesized by the dry heat method or the like is used.
A powder obtained by pulverizing ₂ is preferably 100 μm or less as a starting material. Tetracalcium phosphate can also be produced by a conventional method using the same raw material as the alpha-type tricalcium phosphate, and the powder type particle size is preferably 100 μm or less.

Hardener Main component is water, but hydrochloric acid <HCl to accelerate initial solidification
>, Orthophosphoric acid <H ₃ PO ₄ >, and other inorganic acids; and citric acid, malonic acid, malic acid, lactic acid, glycolic acid, pyruvic acid, and other organic acids within the range of 0.01 to 1.0 normal.

Any known X-ray contrast agent may be used. Further, in order to improve the kneading operability, carboxymethyl cellulose, hydroxyl propyl cellulose, high polyoxyethylene polymer, polyethylene glycol and the like may be added.

Further, in order to increase the porosity of the fired molded body, the fiber may be added in advance.

On the other hand, as a production method thereof, as a formulation example, an admixture is produced by using each component shown in Tables 1 and 2 within a prescribed range, and then, by adding hydrochloric acid, citric acid or the like shown as a curing agent, -Tricalcium phosphate to tetracalcium phosphate becomes a temporary coagulation product after an appropriate time. This temporary solidified product is used to mold into a shape corresponding to the living body healing part. next,
This molded product is fired in the range of 40 ° C to 1200 ° C for an appropriate time. It is set according to the strength of the applied portion, such as the appropriate time and firing temperature.

Next, the present invention will be described in detail using experimental examples.

Experimental Example 1 40 ml of a liquid agent containing 98% by weight of purified water and 2% by weight of hydrochloric acid was mixed with 100 g of α-tricalcium phosphate powder to obtain a mixed mud. Next, this mixed mud was cast-casting, and then calcined at 40 ° C, 60 ° C, and 1200 ° C at a pressure rising rate of 3 ° C / min. The results of measuring the crushing resistance of this fired body are shown in Table 3 (3a).

Experimental Example 2 An experiment similar to Experimental Example 1 was performed except for tetracalcium phosphate powder 100. The results are shown in Table 3 (3b).

Experimental Example 3 100 g of powder containing 50% by weight of α-tricalcium phosphate powder and 50% by weight of tetracalcium phosphate powder was added to purified water.
40 ml of a liquid agent containing 96% by weight and 4% by weight of citric acid was mixed to obtain a mixed mud. After casting and temporarily solidifying this, 3 ℃ / m
The crushing resistance was measured by heating at a temperature rising rate of in and baking at 40 ° C and 600 ° C. The results are shown in Table 3 (3c).

Experimental Example 4 100 g of α-tricalcium phosphate powder, except that the same experiment as in Experimental Example 3 was performed. The results are shown in Table 3 (3d). However, the firing temperature was set to 40 ° C, 600 ° C, and 1200 ° C.

As described in detail above, the present invention has sufficient strength as a substitute for hard tissues in various parts of a living body, and the molded body is molded into a shape according to the shape of the affected part in the temporary solidified body which is a pre-processing step for firing. The temperature range is wide and the baking temperature is wide enough to withstand use even at low temperatures.

Claims (1)

[Claims] 1. A calcium phosphate compound containing water and 0.1 to 1.0.
A method for producing an alternative material for biomedical tissue repair, comprising the steps of: containing a specified organic acid or water and 0.1 to 1.0% inorganic acid, temporarily setting and hardening, and then firing.