JPH02188510A - Curable sizing agent for filling root canal - Google Patents

Abstract

PURPOSE:To provide a two pack type curable sizing agent having excellent affinity with living bodies and used for filling root canals by containing a powder material comprising calcium phosphate powder, calcined magnesium oxide and a vegetable resin and a liquid material comprising a higher fatty acid in a specific ratio. CONSTITUTION:A two pack type curable sizing agent having the above- mentioned effect and used for filling the root canals comprises (A) a powder material comprising 50-75wt.% of calcium phosphate powder, 0.1-25wt.% of calcined magnetism oxide and 20-40wt.% of a vegetable resin (preferably rosin or guaiacum resin) and (B) a higher fatty acid, preferably linoleic acid, linolenic acid and/or oleic acid, in an A/B(g/ml) ratio of >=2. The component may be further compounded with up to 30wt.% of an X-ray contrast medium preferably bismuth oxycarbonate or barium sulfate, thereby permitting the easy confirmation of a root canal-filling state with X rays and the sure treatment of the root canals.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a hardening glue material for root canal filling that has excellent biocompatibility.

In addition, in this specification, all "%" shall mean "weight %."

Prior art and its problems Root canal filling in dental treatment is performed as a final treatment of root canal treatment. Root canal filling methods are broadly divided into the following two methods.

The first method is to mechanically fill the empty root canal with solid materials such as Galata Virtua points, metal points, and resin points, thereby preventing external foreign matter from entering the root canal. This is to prevent intrusion. In this treatment method based mainly on physical or mechanical effects, the shapes of the treatment area and the filling material do not match, making it difficult to reliably fill the root end of the root canal. Therefore, it is often used in combination with gluing described below.

The second method is a hardening adhesive (zinc oxide-clove oil type,
This method uses a resin-based adhesive, etc.) or a non-hardening adhesive (formalin-based, iodoform-based, calcium hydroxide-based, etc.). These adhesives mainly exert biological or therapeutic effects, but as shown below, none of them can be said to be root canal filling materials with excellent biocompatibility.

Hardenable adhesives are mainly used for the purpose of healing the end plate tissue and occluding the root canal. In particular, zinc oxide and clove oil adhesives have an analgesic effect, pulp capping material, luting material, and temporary adhesive material. It has been widely used in various applications. However, this gluing is irritating to the tissue surrounding the root end, and is not satisfactory.

The non-hardening adhesive material is mainly intended for promoting healing of plate end tissues or for healing bony scars. However, formalin-based and iodoform-based woods have a strong antiseptic effect and therefore have the disadvantage of lacking biocompatibility.

In addition, calcium hydroxide-based shelving materials have a strong bony scar healing effect, so they have traditionally been used to treat inflammatory lesions.
As it is non-curing, it is not suitable for long-term use.
Another problem is that it is highly irritating to the plate edge tissue.

Means for Solving the Problems The inventor of the present invention, while conducting intensive research in view of the above-mentioned problems with the prior art, found that it has excellent biocompatibility.
Substitute materials for living tissues such as teeth and bones (implant materials)
We focused on calcium phosphate-based materials, which are used as inorganic constituents.

As a result of further research into the effects of calcium phosphate-based materials on the dental pulp and tissues around the root tip, we found that a material with a specific composition featuring tetracalcium phosphate can be used as a root canal filling material with excellent biocompatibility. I discovered that.

That is, the present invention provides the following curable preparation for root canal filling: (a) 50 to 70% tetracalcium phosphate powder in a 2-material curable preparation for root canal filling; , consisting of a powder material consisting of 0.1 to 25% calcined magnesium oxide and 20 to 40% vegetable resin, and (b) a liquid material consisting of higher fatty acids, with a powder/liquid ratio (g/ml) of 2 or more. A hardened preparation for root canal filling, characterized by the following:

(2) The curable preparation for root canal filling according to the above category [1], wherein the higher fatty acid is at least one of linoleic acid, linolenic acid, and oleic acid.

(2) The curable preparation for root canal filling according to the above category [1], wherein the vegetable resin is at least one of rosin and guaiac resin.

(2) The hardening preparation for root canal filling according to the above category [1], wherein the powder material further contains an X-ray contrast material of up to 30% of the weight of the powder material.

■The hardening preparation for root canal filling described in the above category (■) in which the X-ray contrast material is bismuth oxycarbonate or barium sulfate.

In the present invention, among many calcium phosphate materials, tetracalcium phosphate is particularly used. Since this tetracalcium phosphate has both biocompatibility and bioactivity, it is more stable as apatite in vivo than, for example, hydroxyapatite, which only has biocompatibility. Further, although α-tricalcium phosphate has biocompatibility and bioactivity comparable to that of tetracalcium phosphate, the amount of calcium per unit molecule is smaller than that of tetracalcium phosphate. Therefore, after the neutralization reaction with acid, it is difficult to reach pH 7.0, which is the most desirable state from the viewpoint of biocompatibility, and the problem is that the disintegration rate is about twice that of tetracalcium phosphate. Yes, it cannot be used.

The tetracalcium phosphate used in the present invention as the main component in the powder material (a) is not particularly limited in terms of its manufacturing method, but it is desirable that the content of hydroxyapatite and the like is as low as possible. Such high-purity tetracalcium phosphate can be obtained, for example, by mixing calcium diphosphate or calcium diphosphate dihydrate and calcium carbonate at a molar ratio of 1:1, and then heating the mixture in the atmosphere at 1600 to 1650°C for 2 hours. It is obtained by heating in a furnace to a certain extent to make it into a molten or semi-molten state, and then allowing it to cool naturally in the furnace until it becomes 400° C. or less, and then cooling it outside the furnace. When the heating temperature is less than 1600°C, the amount of hydroxyapatite produced tends to increase. The proportion of tetracalcium phosphate in the width of powder material (a) is 5
The range is 0 to 75%. If the proportion of tetracalcium phosphate is less than 50%, the biocompatibility as a filler will be insufficient, while if it exceeds 75%, the curing time will be shortened, making treatment work difficult. Become.

The calcined magnesium oxide that constitutes a part of the powder material (a) is
It is blended in order to reduce the curing speed and adjust the curing time of the prepared material of the present invention. Calcium hydroxide, which has properties similar to calcined magnesium oxide, cannot be used because it significantly shortens the hardening time of the shelving material. The proportion of calcined magnesium oxide in the powder material (a) is in the range of 0.1 to 25%. When the proportion of calcined magnesium oxide is less than 0.1%, hardening is not controlled, while when it exceeds 25%, hardening is excessively suppressed and the hardening rate is significantly reduced.

Due to its water repellency, the vegetable resin, which is another component of powder material (a), prevents internal acids from entering the root tip and prevents inflammation that may occur between the internal acid and the root tip. It works to prevent. As such a vegetable resin, rosin or guaiac resin is used. The proportion of vegetable resin in the width of powder material (a) is 2
The range is 0 to 40%. If the proportion of vegetable resin in the powder material (a) is less than 20%, it will not be possible to sufficiently prevent the intrusion of internal acids into the root tip, and the reaction between internal acids and tetracalcium phosphate will be inhibited. This shortens the curing time of the shelf material, whereas if it exceeds 40%, the curing time becomes significantly longer.

In the present invention, the powder material (a) and the liquid material (b) made of higher fatty acids are used together. As such a higher fatty acid, at least one of linoleic acid, linolenic acid, and oleic acid is used, which has no medical effect on living organisms, is liquid at room temperature, and is insoluble in water. Although no difference in performance is observed between these, oleic acid is more preferred in terms of ease of mixing with powder material (a). Because of their excellent water repellency, these higher fatty acids, like the vegetable resin in powder material (a), have the function of preventing inflammation at the root tip caused by body acids and adjusting the hardening time of the filling material. Has a function. The ratio of powder material (a) and liquid material (b) used is usually 1 to 4 g or more, preferably about 2 to 3 g, of powder material (b) per 1 ml of liquid material (b).

In addition, in the present invention, the powder material (a) is 3% of the powder material weight.
It may further contain up to 0% X-ray contrast material. In this case, it becomes easy to confirm the filling state of the root canal using X-rays, and it becomes possible to perform root canal treatment reliably. The X-ray contrast material is not particularly limited as long as it does not affect the performance of the hardened wood for root canal filling according to the present invention, but bismuth oxycarbonate or barium sulfate is particularly suitable.

The content in the powder material (a) is more preferably 10 to 30%. If it is less than 10%, the contrast properties may be insufficient, and if it exceeds 30%, although the contrast properties are improved, other properties are degraded.

Effects of the Invention According to the hardening adhesive for root canal filling of the present invention, the following remarkable effects can be achieved.

(b) Since the main ingredient is tetracalcium phosphate, which has both biocompatibility and bioactivity, it can be applied to the affected area for a long period of time.
Does not cause any trouble.

(b) There is also very little stimulation to the plate edge tissue.

(c) The curing time can be adjusted appropriately by changing the ratio of the powder material (a) and the liquid material (b) depending on the dentist's treatment method.

(d) Since it is a two-material preparation consisting of powder material and liquid material,
Excellent effects can also be achieved when used in combination with conventional solid root canal filling materials.

(f) Does not require any special equipment and has excellent workability.

EXAMPLES Examples and comparative examples are shown below to further clarify the features of the present invention.

Examples 1 to 11 After preparing powder material (a) and liquid material (b) using each material in the proportions shown in Table 1, ISO standard 6876-19
86, the physical properties as a hardening glue material for root canal filling were measured.

The results are shown in Table 3 together with the results of the comparative examples below.

In addition, each symbol in Table 1 represents the following materials and items.

■... Tetracalcium phosphate ■... Calcined magnesium oxide ■... Rosin ■... Guayac resin ■... Bismuth oxycarbonate ■... Barium sulfate ■... Linoleic acid ■... Linolenic acid ■...Oleic acid The physical properties of a hardening adhesive for root canal filling were measured.

The details are as follows.

Comparative Example]..."Apatite Root Sealer Type ■", Sankin Kogyo Co., Ltd. Comparative Example 2..."Neodyne", Neo Pharmaceutical Kogyo Co., Ltd. Comparative Example 3...Same as above Comparative Example 4...Same as above Comparative Example 5: Described in JP-A-62-255403.

In addition, in Table 2, P/L refers to 1ml of liquid material.
Represents the number of grams of powder per serving.

Table 2 Powder material Liquid material P/L Comparative example 1 α-triphosphoric acid Organic polymeric acid 1.25 Calcium zinc oxide clove oil 3.0 Zinc oxide clove oil 4.0 Zinc oxide clove oil 5.0 5 Hydroxy acid Mixture of Abbatite (guaiacol eucalyptus butorrosine olive oil) 2.0 Table Experimental Example 1 The hardening adhesive for root canal filling shown in the above examples and comparative examples was applied to 150 root canals of mandibular premolars of 15 adults. After 3 months, histopathological examination was performed.

Table 4 shows the results.

In Table 4, "closed by newly generated hard tissue" means that the root canal was closed by newly generated hard tissue. This indicates that tetracalcium phosphate has biocompatibility and bioactivity, and therefore causes almost no inflammation in the tissues surrounding the root tip and does not interfere with the natural healing action of existing tissues. It is something.

No. table Procedural amendment stamp system March 6, 1999

Claims (1)

[Scope of Claims] [1] In a two-material type hardening glue material for root canal filling, (a)
It consists of a powder material consisting of 50-75% tetracalcium phosphate powder, 0.1-25% calcined magnesium oxide, and 20-40% vegetable resin, and (b) a liquid material consisting of higher fatty acids, and the powder/liquid ratio is (g/ml) of 2 or more. [2] The curable adhesive for root canal filling according to claim 1, wherein the higher fatty acid is at least one of linoleic acid, linolenic acid, and oleic acid. [3] The curable glue material for root canal filling according to claim 1, wherein the vegetable resin is at least one of rosin and guaiac resin. [4] The hardening glue material for root canal filling according to claim [1], wherein the powder material (a) further contains an X-ray contrast material in an amount of up to 30% of the powder material weight. [5] The hardening glue material for root canal filling according to claim 4, wherein the X-ray contrast material is bismuth oxycarbonate or barium sulfate.