JP3208585B2 - Method for producing hardened neutral bone formation - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a hardened neutral bone formation used for filling a root canal, a bone filling material, a bone cement, a purulent tooth, and the like.

[0002]

2. Description of the Related Art Conventionally, as a curable composition using chitosan which is a natural polymer, an acidic aqueous solution in which chitosan is dissolved and a basic water-curable inorganic substance are mixed to make the entire system basic. There is a water-curable inorganic substance characterized in that:
This curable composition is based on the fact that the solubility of chitosan decreases in the basic region and becomes insoluble. As the basic water-hardened inorganic composition, lime, Portland cement, alumina cement and the like are used. About the basicity of the whole system after mixing, pH 9 or more is desirable. Other examples of the curable composition include an aqueous chitosan solution, hydroxyapatite, zinc oxide and / or zinc oxide.
Alternatively, a curable composition is produced by mixing magnesium oxide. Since the curable composition contains apatite, it has excellent affinity for teeth, bones, and the like, and has a characteristic of being cured near neutrality. (Japanese Unexamined Patent Publication No.
(See JP-A-208347) Chitosan is a calcium and calcium salt that is found in crustaceans, insect shells and fungi.
Present as a complex of proteins. This chitosan is obtained by deacetylating chitin and is a polysaccharide having an amino group. Furthermore, chitosan is used for plant fiber, cosmetics, porous carriers, adsorbents, soil conditioners, and the like. These are based on the fact that chitosan is a polyamine and easily forms a complex.

[0003] On the other hand, in the field of dentistry, dental cements such as coalescence of restorations, temporary filling, and root canal filling are used. Examples of dental cements include zinc linsan, zinc / eugenol, carboxylate, and the like. It is used by mixing powder and liquid at the time of use, and has a curing time of 4 to 10 minutes.

[0004]

However, any paste prepared by mixing a cement powder and a liquid in a dental cement has a pH of 2 to 4, that is, is acidic, and causes pulp damage in vivo. There is a problem.

[0005] In addition, granular apatite used as a bone filling material moves from the initial filling position,
For example, there is a problem that gingiva is inflamed due to occlusal pressure by entering between gingiva and bone.

[0006] Furthermore, the curable composition containing the apatite granules described above is not effective for bone formation because the granules may move and be excluded.

[0007] Therefore, an object of the present invention is to provide a non-toxic substance in a living body, a cured product near neutral after completion of a chemical reaction, and excellent ossification without gingival inflammation due to occlusal pressure. To provide a hardened neutral bone formation.

[0008]

According to the present invention, an animal bone is provided.
Baking the mineral bone only, and crushing the animal bone
The process of making animal bone meal, zinc oxide and calcium oxide
The at least one oxide and the animal bone meal
Mixing powder at a mixing ratio of
Kneading with the chitosan sol dissolved in
Thus, a method for producing a hardened neutral bone formation product is obtained.

Further, according to the present invention, animal bone is calcined and
A process to make only the substance, and crush this animal bone to animal bone meal
The process of making zinc oxide and calcium oxide
At least one oxide, said animal bone meal, and chemically synthesized
Mixed apatite at a predetermined mixing ratio to make a mixed powder
Step and kneading the mixed powder with chitosan sol dissolved in acid
Hardening neutral bone formation, comprising:
A method for manufacturing a product is obtained.

According to the present invention, the mixed powder is produced.
In the step, together with the oxide, a magnet oxide
Curing characterized by mixing the calcium at a predetermined mixing ratio
A method for producing a model neutral bone formation is obtained.

[0011]

[0012]

[0013]

[0014]

[0015]

According to the present invention, a kneaded mud of a hardened, neutral bone-forming product, which is a hardened, neutral, homogeneous product, is produced by kneading a mixed powder and a chitosan sol. When this hardened neutral bone formation is filled in or near bone, bone is created. The condensed mud hardens in a few minutes, and a curable neutral bone formation having a pH in the range of 6 to 8 is obtained. Animal bone meal is about twice as fast as apatite at conducting bone. The chitosan sol is gelled to fix the apatite granules, and when the chitosan is absorbed into the living body, an osteoid matrix is recognized and the chitosan sol is replaced with bone. In this hardened neutral bone formation, zinc oxide or calcium oxide may be used alone as a neutralizing agent,
Alternatively, the main component is zinc oxide.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The hardened neutral bone formation of the present invention is an osteoconductive material. The osteoconductive material has a property of producing bone when a substance is filled near or in bone in the field of dental care.

A first embodiment of the hardened neutral bone forming material of the present invention will be described below. A hardened neutral bone formation can be obtained by mixing animal bone meal, an oxide of a Group II metal, and chitosan sol to obtain a neutral and uniform hardened product. In particular, the present invention focused on the fact that calcined inorganic animal bone powder is about twice as fast as apatite in conducting biological bone. The animal bone meal described herein is obtained by crushing bones of non-human animals. For example, animal bone meal is selected from bones of animals living on land such as cow bones and pig bones and bones of animals living in the sea. The hardened neutral bone formation has animal bone powder, a mixed powder obtained by mixing zinc oxide and calcium oxide, which are oxides of Group II metals, and chitosan sol dissolved by an acid. Kneaded mud is obtained by kneading the mixed powder and chitosan sol. Zinc oxide and calcium oxide are used as neutralizing agents. In particular,
The more zinc oxide, the faster the cure rate. Zinc oxide or calcium oxide may be used alone, or zinc oxide may be mainly mixed with calcium oxide.

Further, the method for producing a hardened neutral bone product in the first embodiment is performed as shown in FIG. And animal bones was fired 3-7 hours at 800 ° C. C. to 1100 ° C. firing step S ₁ that only inorganic, and the grinding step S ₂ to produce an animal bone powder by pulverizing the animal bones, animal bone powder and zinc oxide and calcium oxide each and mixing step S ₃ to make a mixture powder mixed at a predetermined mixing ratio to obtain a kneaded mud with a step S ₄ of kneading the mixed powder with chitosan sol prepared by dissolving in acid.

Next, as a second embodiment, the hardened neutral bone forming material is a mixed powder obtained by mixing animal bone powder, apatite, zinc oxide and calcium oxide which are oxides of Group II metals,
And chitosan sol dissolved by an acid. The mixed powder and the chitosan sol are kneaded to obtain a kneaded mud. Also in this hardened neutral bone forming material, zinc oxide or calcium oxide may be used alone, or it is preferable that zinc oxide or calcium oxide is mainly used.

Further, the method for producing a hardened neutral bone formation product of the second embodiment is performed as shown in FIG. A firing step S ₁ that only inorganic calcined animal bone, the milling step S ₂ to produce an animal bone powder by pulverizing the animal bones, chemically synthesized apatite (hydroxyapatite, alpha type - tricalcium phosphate Hate, β-type - tricalcium phosphate hate), and mixing step S ₃ to make animal bone powder, and mixed powder by mixing zinc oxide and calcium oxide at respective predetermined mixing ratio, is triturated with chitosan sol prepared by dissolving a mixed powder with acid obtaining a kneaded mud with a kneading step S _4. In the hardened neutral bone formation containing apatite granules, the apatite granules are not moved or eliminated. That is, since the chitosan sol gels and fixes the apatite granules,
At the time when chitosan is absorbed into a living body, an osteoid matrix is recognized and is replaced by bone.

When bovine bone meal is used as an inorganic animal bone powder, as described above, bovine bone powder has a characteristic that the speed of conduction of biological bone is faster than that of apatite.
The time for forming the bone of the living body is short. Therefore, when the ratio between the bovine bone meal and the apatite is shown, the first embodiment contains only the bovine bone meal without the apatite. In the second embodiment, the ratio of beef bone meal to apatite was 9%.
When 9 W%, bovine bone meal is 1 W%, and apatite 50
When it is W%, beef bone meal is 50 W%. The ratio of the mixed powder of the second embodiment is, for example, as follows.

Calcium oxide 0.5-35 W% Zinc oxide 0.5-35 W% Beef bone meal and apatite 10-99 W% Further, in the present invention, if necessary, magnesium oxide as a neutralizing agent is further added to the mixed powder, 0.05-20W
% Mix. The operability can be improved by reducing the size of the bovine bone powder to 100 μm or less, preferably 74 μm or less. That is, the fluidity is improved in the chitosan sol, and the chitosan sol is easily filled. In addition, kneaded mud hardens in 3 to 10 minutes,
A hardened neutral bone formation having a pH in the range of 6 to 8 is obtained.

The acid used for chitosan may be any acid that dissolves chitosan. Specifically, as an acid,
Acetic acid, formic acid, lactic acid, malic acid, citric acid, adipic acid,
Tartaric acid, malonic acid and the like are used. With this acid,
The dissolved chitosan can be made into an acidic sol.

In the present invention, chitosan 0.05 to
Chitosan sol can be formed from a solution prepared by dissolving 0.125 g of acid in 0.05 to 0.255 g of acid using 2.0 cc of distilled water or physiological saline.

The components of the mixed powder are as described below.

Zinc oxide 0.01 to 0.100 g Calcium oxide 0.01 to 0.100 g Magnesium oxide 0 to 0.005 g Beef bone meal 0.05 to 1.00 g Apatite 0 to 1.00 g Calcium can reduce the amount of zinc oxide and magnesium oxide and increase the amount of apatite. In this case, the pH is appropriately selected from the above range according to a desired curing speed and the like. However, when the ratio of calcium oxide is high, the pH of the cured product exceeds 8, and thus it is desirable to set the range. Table 1 shows the results of kneading a mixed powder using beef bone meal and apatite with a chitosan sol dissolved with malic acid and malonic acid.

[0027]

[Table 1]

In the results shown in Table 1, the curing time (minute)
As a result, the time was significantly shortened when malonic acid was used as compared with when malic acid was used. Therefore, it was possible to compensate for the shortening of the curing time by using the chitosan sol dissolved with malonic acid.

Next, the most important thing in vivo is that the material used has no toxicity, and it is desirable that the product be neutral after the completion of the chemical reaction. Therefore, the pH value was measured. p
The measured values of H are shown in FIG. FIG. 3 shows a mixture of calcium oxide 0.03 g, zinc oxide 0.045 g, beef bone 0.2 g, apatite 0.2 g, malonic acid 0.1 g, chitosan 0.125 g, and physiological saline 2.0 g. It is a hardened neutral bone forming product obtained by kneading the produced chitosan sol. As is clear from FIG. 3, the hardened neutral bone formation obtained a result in which the pH was kept almost constant in the vicinity of neutrality in the range of 6 to 8 with time.

Next, Table 2 shows the compressive strength of the hardened neutral bone formation product.

[0031]

[Table 2]

Further, in the tissue observation, 0.2 g of bovine bone meal,
0.2 g of hydroxyapatite, 0.1 g of calcium oxide.
A mixed powder of 03 g and zinc oxide (0.045 g) was dissolved in malonic acid (0.1 g) with physiological saline (2.0 cc) to prepare a chitosan sol using chitosan (0.125 g), and this chitosan sol was kneaded. A recess was formed in the skull of a rat with a bone bar under water injection, and the recess was filled into the recess. 4
After a week, the rats were sacrificed, and the tissues were observed. Four weeks later, the osteoid matrix stained with the eosin staining solution was strongly observed. Hydroxyapatite, which contained no bovine bone meal and was used in the same manner as a control, showed only slight osteoid formation.

[0033]

As described above, according to the curable neutral bone forming material of the present invention, since the pH of the prepared cured product is in the range of 6 to 8, The product is a hardened product in the vicinity of neutrality for the living body, and is excellent in bone formation such as a root canal filling material, a bone filling material, a bone cement, and fixation of pyorrhea without pulp disorders.

Further, since the hardened neutral bone formation maintains an elastic state in a living body, even if it is filled between the gingiva and the bone to regenerate the jaw bone, gingival inflammation due to occlusal pressure is caused. Does not occur.

[Brief description of the drawings]

FIG. 1 is a process explanatory view showing a method for producing a hardened neutral bone formation product according to a first embodiment of the present invention.

FIG. 2 is a process explanatory view showing a method for producing a hardened neutral bone formation product according to a second embodiment of the present invention.

FIG. 3 shows the pH of one embodiment of the hardened neutral bone formation product of the present invention.
It is a graph which shows the measurement result of a value.

[Explanation of symbols]

S ₁ firing process S ₂ grinding process S ₃ mixing process S ₄ kneading process

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) A61L 27/00-27/58 A61L 24/00-24/12 A61C 13/08-13/097

Claims (3)

(57) [Claims] 1. A process for baking animal bone to make it inorganic only.
Crushing the animal bone to produce animal bone meal;
Lead, at least one oxide of calcium oxide,
And the animal bone meal is mixed at a predetermined mixing ratio to form a mixed powder.
And mixing the mixed powder with a chitosan sol dissolved in an acid.
Hardening neutral bone shape, comprising
A method for producing a product. 2. A process in which animal bone is calcined to make it only inorganic.
And the process of crushing this animal bone to make animal bone meal, oxidation
Oxidation of at least one of zinc and calcium oxide
Material, the animal bone meal, and chemically synthesized apatite
Mixing at a predetermined mixing ratio to produce a mixed powder;
Kneading with a chitosan sol dissolved in acid.
A method for producing a hardened neutral bone formation. 3. The method according to claim 1 , wherein the step of preparing the mixed powder comprises the step of:
Magnesium oxide together with magnesium oxide at the specified mixing ratio
3. Curing according to claim 1 or 2, characterized in that:
A method for producing a type neutral bone formation.