JPH0228104A - Root canal filler - Google Patents

Abstract

PURPOSE:To obtain a root canal filler usable with gutta-percha points in combination by using alpha-tricalcium phosphate and iodoform powder as a dust and an aqueous solution of a polyalkylene glycol as a curing solution in combination in a specific proportion. CONSTITUTION:A root canal filler consisting of a dust (P) consisting of 100 pts.wt. alpha-tricalcium phosphate and 5-30 pts.wt., especially 15-25 pts.wt. iodoform powder and a curing solution (L) consisting of a 5-15wt.% aqueous solution of a polyalkylene glycol at 1.0-2.0 weight ratio (P/L). The above-mentioned root canal filler has biocompatibility due to use of the alpha-tricalcium phosphate chemically close to ingredients of teeth with excellent adhesion to gutta-percha points and operability without irritancy because of a nearly neutral state of about pH7.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a root canal filling material used in dental treatment, and particularly to a root canal filling material that is effective for root canal filling treatment when used in combination with gutta percha points. It is related to materials.

[Prior art and its problems to be solved]

In dental treatment, when treating pathological causes such as pulpitis and infected root canals, root canals that have become cavities caused by pulp extraction or the like are treated by means such as filling with root canal filling material.

Typical conventional root canal filling treatments include a method in which only root canal filling material is tightly filled into the root apex, and a method in which gutta percha points and root canal filling material are used together to fill and seal the root canal. It is something.

Calcium hydroxide glue is known as the typical root canal filling material used in the former method.
Furthermore, zinc oxide nisinol cement is known as a typical root canal filling material 7 used in the latter method.

However, when calcium hydroxide-based wood is used, there is a problem in that it causes irritation because the pH increases in the vicinity of the filled material. On the other hand, when zinc oxide nisinol cement was used, there was a problem that it had no biocompatibility.

In addition, biocompatible α-
There are examples of using tricalcium phosphate powder, but since this root canal filling material uses polyacrylic acid aqueous solution as the curing liquid, this also lowers the pH and has problems such as poor operability. was there.

The inventors of the present invention, in view of the current situation, have conducted intensive studies on root canal filling materials in order to solve the above-mentioned problems, and have arrived at the present invention.

[Means to solve the problem]

That is, the present invention consists of a powder [P] consisting of 100 parts by weight of α-tricalcium phosphate powder and 5 to 30 parts by weight of iodoform powder, and a curing liquid [Ll] consisting of a 5 to 15% by weight aqueous solution of polyalkylene glycol. and the weight ratio of [P] and [L] [
The present invention relates to a root canal filling material in which P]/[L] is 1.0 to 2.0.

The following properties are generally required for root canal filling materials.

(1) The root canal filling material mixture has appropriate kinematic viscosity, blends well with gutta-percha points, and easily adheres to it.

(11) When created outside the apical foramen, it does not pierce the periodontal tissue and is quickly absorbed.

(iii) It has an appropriate curing time and has a working time.

(1■) Excellent sealing properties.

(v) It has X-ray contrast property.

(vi) Good operability.

The root canal filling material of the present invention is biocompatible and is an epoch-making material that satisfies the above-mentioned required properties.

The present invention will be explained in detail below.

The powder agent [P] constituting the root canal filling material of the present invention consists of α-tricalcium phosphate powder and iodoform powder.

The α-tricalcium phosphate can be produced by a known method, for example, by the following method.

That is, calcium T-pyrophosphate and calcium carbonate were uniformly mixed in equimolar amounts, thoroughly dried, and then
It can be obtained by calcining at ~1400°C, preferably around 1250°C for about 1 hour, and pulverizing the resulting product into a fine powder with a particle size of 100 μm or less. Alternatively, it can be obtained by uniformly mixing calcium hydrogen phosphate dihydrate and calcium carbonate at a molar ratio of 2:1, and then calcining and pulverizing the mixture under substantially the same conditions as in the above method.

The particle size of the powder is preferably 20 μm or less.

Further, the iodoform powder that has been conventionally used for this type of application can be used, and the particle size of the powder is preferably 10 μm or less.

The amount of iodoform powder to be blended is 5 to 30 parts by weight, particularly preferably 15 to 25 parts by weight, per 100 parts by weight of α-tricalcium phosphate.

If the amount of iodoform powder blended is too small than the above range, the X-ray contrast properties of the root canal filling material will be insufficient, and adhesion to gutta-percha points and root canal walls will deteriorate, which is not preferable. On the other hand, if it is in excess of the above range, the amount of α-tricalcium phosphate will be relatively small, which will deteriorate the hardenability of the root canal filling material, which is not preferable.

As explained above, the powder IP used in the present invention consists of α-tricalcium phosphate powder and iodoform powder, but if necessary, barium sulfate powder, basic bismuth carbonate powder, silica powder, alumina powder, apatite powder, etc. Powder etc. may also be blended.

Next, the hardening liquid CLI constituting the root canal filling material of the present invention is an aqueous solution of polyalkylene glycol.

Polyalkylene glycol is polyethylene glycol,
Typical examples include polypropylene glycol or copolymers thereof, which are preferably nonionic and have a linear molecular structure without ester bonds, with some of the terminal hydroxyl groups linked to ether bonds. Anything is fine.

In addition, polyalkylene glycol has a minute F4 of about 2000
Above, the kinematic viscosity is 10 to 1000 cS in a 10% by weight aqueous solution.
t (25°C) is the kinematic viscosity of the root canal filling material mix;
This is preferable because it has good operability.

In addition, the concentration of polyethylene glycol aqueous solution is 5-15
If the weight % is appropriate, and the aqueous solution concentration is less than the above range, the viscosity will be lost during kneading, resulting in poor workability.

On the other hand, if it is larger than the above range, the solubility of the kneaded and cured product increases and the strength decreases, which is not preferable.

The hardening liquid CL used in the present invention is, as explained above, made of an aqueous solution of polyethylene glycol, which may be chlorinated if necessary), ammonium chloride, water-soluble salts of calcium or magnesium, and a thickener. , a surfactant, etc. can also be added in small amounts.

The root canal filling material of the present invention is composed of the powder CPil and the curing liquid [L] as described above, and the weight ratio [:P] / [L] of CP] and [+-, ] is 160 to 2. It is kneaded and used at a ratio of .0.

In addition, if the [P] / [:Ll] ratio is less than 1.0, the viscosity of the kneaded product will be low and a viscous kneaded product will not be obtained, and the workability of filling the root canal will be poor. Become. On the other hand, if it exceeds 2.0, it becomes difficult to knead, and furthermore, the kneaded product has no viscosity and becomes rough, which is not preferable.

The powder agent [P] and hardening liquid [L] of the present invention are kneaded just before use, and then used.

The method for kneading the root canal filling material of the present invention is not particularly limited, and any method conventionally used in the field of dental bath cement may be used, for example, the method specified in JIS-T6602 can be used.

〔Effect of the invention〕

The root canal filling material of the present invention has α-
Since tricalcium phosphate is used, it is biocompatible, and since it is around neutral at around 9117, there is no eastward magnetism, and it also has the properties required as a root canal filling material, such as gutta percha point. Since it has excellent adhesion and operability, it is suitable as a root canal filling material.

Hereinafter, the present invention will be explained in more detail with reference to Examples.

Examples 1 to 3 and Comparative Examples 1 to 4 Calcium T-birophosphate and calcium carbonate were mixed in equimolar amounts by a known method, baked to synthesize α-tricalcium phosphate, and pulverized to pass through a 300-mesh sieve. In this way, α-tricalcium phosphate powder with a predetermined particle size was obtained.

The α-tricalcium phosphate powder thus obtained (
α-TCP) was mixed with other powder components shown in Table 1, and kneaded with the hardening liquid shown in Table 1 in accordance with the method of JIS-"I"6602.

(Numbers on the surface indicate duplicate parts.) The maneuverability, adhesion to gutta-percha points, and X-ray contrast properties of the thus prepared kneaded product were investigated, and the results are shown in the lower column of Table 1. .

Separately, the powder and the curing liquid are uniformly kneaded for 1 minute,
Place the kneaded product in a container, flatten the surface and place a filter paper on it, and 150 seconds after the start of kneading, water is added dropwise to moisten the filter paper,
After sealing and leaving for 24 hours, use Fura Notoya 1pH electrode (Beckman flat type decoupling electrode #395233-502A)
was brought into contact with filter paper and the surface pH of the kneaded product was measured.

As is clear from the test results in Table 1, the root canal filling material of the present invention has a pH near neutrality, very low biomass magnetism, and has excellent operability, adhesion to gutta-percha points, and It had good radiographic properties and was suitable as a root canal filling material.

On the other hand, the comparative examples in which a polyacrylic acid aqueous solution and a sodium polyacrylate aqueous solution were used as the curing liquid had poor operability and were unsuitable.

Note 1) Nonionic polyethylene glycol with a molecular weight of 3000 Note 2) Acrylic acid-itaconic acid copolymer (itaconic acid content 35% by weight) Note 3) Degree of polymerization 2700-7500 Note 4) Operability of kneaded product ( At the time of synthesis, judgments were made regarding whether the consistency of the JIS-T6602 standard was met during kneading and whether the filling workability was good.

Note 5) The powder and hardening liquid were uniformly kneaded for 1 minute, and the adhesion to gutta-percha points was examined 5 minutes after the start of kneading.

Note 6: 80kV, 200mA X for 2mm thick cured material
The X-ray film was exposed to 1M for 0.02 seconds and examined.

Claims (1)

[Scope of Claims] A powder agent [P] consisting of 100 parts by weight of α-tricalcium phosphate powder and 5 to 30 parts by weight of iodoform powder, and a curing liquid [L] consisting of a 5 to 15% by weight aqueous solution of polyalkylene glycol. , and the weight ratio of [P] and [L] is [P]/[
A root canal filling material in which L] is 1.0 to 2.0.