JPH01279815A - Treating agent for surface of tooth - Google Patents

Abstract

PURPOSE:To provide a treating agent for treating the surface of tooth to strongly adhere a tooth therapeutic agent to the dentine of the tooth by adding a constant amount of a metal chloride such as calcium chloride and water to an organic carboxylic acid such as citric acid or an acid anhydride thereof. CONSTITUTION:A tooth surface-treating agent for treating the surfaces of enamel and/or dentine comprises an organic carboxylic acid (especially, citric acid, cinnamic acid, oxalic acid, tartaric acid, ethylene tetracarboxylic acid, salts thereof, etc.,) or an acid anhydride thereof, a metal chloride consisting of potassium chloride, calcium chloride or a mixture thereof and water wherein the concentrations of the organic acid or the acid anhydride thereof and the metal chloride are 5-50wt.% and 5-50wt.%, respectively, based on the total amount of the composition. Particularly, a tooth surface-treating agent for strongly adhering a filling and repairing material, a pit fissue-packing material, an adhesive cement, etc., to the tooth surface on the therapy of dental caries, etc., with these material is provided.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention is used in the field of dentistry to treat the surface of a tooth or the inner surface of a cavity when treating the tooth using a material that has adhesive properties. Regarding surface treatment agents. In particular, filling repair materials such as composite resin, pit and fissure filling materials,
The present invention relates to materials used to treat tooth surfaces in order to firmly adhere these materials to tooth structure when treating cavities and the like using adhesive cement.

(Conventional technology) In order to bond organic materials (composite resin, glass ionomer cement, carboxylate cement, composite resin cement, pit and fissure fillers, etc.) used in the treatment of dental caries to the tooth surface, enamel is coated with an acid aqueous solution. etc. are being processed. As this processing agent,
Aqueous solutions of phosphoric acid and citric acid with various concentrations are recommended as tooth surface treatment agents, but from the viewpoint of treatment effects, phosphoric acid aqueous solutions with a concentration of 20 to 60% by weight are most commonly used.

In particular, composite resins used for filling and restoring carious areas are made of synthetic resin and inorganic filler. The method involves etching the enamel wall of the cavity from which the carious area has been removed using an acid aqueous solution (for example, a phosphoric acid aqueous solution), and applying an adhesive made of a polymerizable monomer, which is a synthetic resin component of the composite resin, to the treated surface. It is known that the tooth surface is made up of enamel and dentin, and when performing a filling restoration, a cavity created by removing the carious part is used. Due to the presence of walls of enamel and dentin, it is desirable to bond the composite resin strongly to both the enamel and the dentin.For this reason, adhesives containing special polymerizable monomers that bond to dentin are used. agents are now being used.

By the way, when tooth substance is removed with a grinding tool, cutting waste adheres to the adhesive surface. It is estimated that this cutting waste contains bacteria present in carious areas and bacteria floating in the oral cavity. If this cutting waste is left in place and repaired with a composite resin, etc., even if the composite resin and the cutting waste are strongly bonded, the adhesion between the tooth surface and the cutting waste will be insufficient, and peeling will occur between them. will occur. There is also a concern that the bacteria present in the cuttings may irritate the dental pulp. For this reason, it is desirable to remove the cutting debris before filling and repairing with composite resin. If the entire cavity is treated with the above-mentioned phosphoric acid aqueous solution, the cutting debris adhering to the enamel and dentin surfaces will be completely removed, but the dentinal tubules that were blocked by the cutting debris will open, allowing the irritating substances to open. There is also concern that it may reach the dental pulp through the dentinal tubules and cause harmful effects.

Therefore, research has been carried out on using various organic carboxylic acids as tooth surface treatment agents for dentin in place of phosphoric acid.
Enamel is treated with a tooth surface treatment agent that is effective as a dentin treatment agent when used with aqueous solutions such as citric acid, oxalic acid, and formic acid, and/or metal salts such as ferric oxalate and iron chloride. However, the adhesion between the Hunposit resin and the enamel is not as strong as when treated with a phosphoric acid aqueous solution. Therefore, when using such a tooth surface treatment agent, it is necessary to first treat the dentin with an organic carboxylic acid or the like and then treat the enamel again with an aqueous phosphoric acid solution or the like, resulting in a complicated operation.

(Problems to be Solved by the Invention) As mentioned above (tooth surface treatment agents made of organic carboxylic acids are effective for dentin, but cannot exhibit sufficient treatment effects for enamel. Therefore, when using such tooth surface treatment agents, it is necessary to treat the dentin and then treat the enamel again with a phosphoric acid aqueous solution, which requires complicated operations from a clinical standpoint, and tooth surface treatment. It is unsuitable for general use as an agent.

In addition, the most important characteristic of tooth surface treatment agents is the treatment effect to enhance adhesive strength to enamel and dentin, but ivory! It is also desirable that the denaturing effect of (particularly collagen) is small.

(Means for Solving the Problems) The present inventor focused on this point, and as a result of intensive study on a tooth surface treatment agent that can simultaneously treat enamel and dentin in place of phosphoric acid, the present invention was achieved.

In other words, an organic carboxylic acid that is said to have no harmful effect on the dental pulp even if the dentin surface is treated as a substrate for a tooth surface treatment agent, and a specific additive that enhances the treatment effect of this organic carboxylic acid on enamel. After intensive study on the concentration of enamel and its concentration, we came up with a tooth surface treatment agent that can treat enamel and dentin at the same time.

The tooth surface treatment agent of the present invention contains an organic carboxylic acid, a metal chloride, and water as main components.

The organic carboxylic acids that can be used in the treatment agent of the present invention include monocarboxylic acids, dicarboxylic acids, tricarboxylic acids, tetracarboxylic acids, and their acid anhydrides. Monocarboxylic acids and their acid anhydrides include formic acid, acetic acid,
Lactic acid, butyric acid, valeric acid, nonanoic acid, hexanoic acid, heptanoic acid, lauric acid, pyruvic acid, glycine, methacrylic acid, acrylic acid, crotonic acid, benzoic acid, ami7benzoic acid, salicylic acid, aminosalicylic acid, acetic anhydride, anhydride Examples include butyric acid, valeric anhydride, lauric anhydride, glycine anhydride, crotonic anhydride, and benzoic anhydride. Examples of dicarboxylic acids and their acid anhydrides include oxalic acid, succinic acid, tartaric acid, glutaric acid, fumaric acid, maleic acid, malonic acid, citraconic acid, itaconic acid, (o, m, P) phthalic acid, (α, β -) Naphthalic acid, 2.3-naphthalenedicarboxylic acid, 2-methacryloyloxyethyl trimellitic acid, and succinic anhydride, maleic anhydride, citraconic anhydride, itaconic anhydride, phthalic anhydride,
α.

Examples include β-)naphthalic acid, 1,8-naphthalene dicarboxylic anhydride, and 2-methacryloyloxyethyltrimellitic anhydride. Examples of tricarboxylic acids and their acid anhydrides include citric acid, trimellitic acid, trimellitic acid, and trimellitic anhydride. As the tetracarboxylic acid and its acid anhydride, ethylenediaminetetraacetic acid (EDTA) or a salt thereof, pyromellitic acid, pyromellitic anhydride, and the like are used. Moreover, (meta)a, two or more kinds may be mixed and used. Among these organic carboxylic acids, citric acid, succinic acid, oxalic acid, tartaric acid, or ethylenediaminetetraacetic acid or its salt,
Maleic anhydride, succinic anhydride and the like are preferred. The concentration of the organic carboxylic acid in the composition consisting of the organic carboxylic acid, metal chloride and water may be 5 to 50% by weight. More preferably, the concentration is 5 to 30% by weight. In the case of citric acid, it is preferably 5 to 30% by weight. Outside the above range, the etching effect will be insufficient.

The metal chloride that can be used in the treatment agent of the present invention is potassium chloride, calcium chloride, or a mixture thereof, as long as the concentration in the composition is 5 to 50% by weight. Among these, calcium chloride with a concentration of 5 to 30% by weight is preferred.

By the way, Kojima et al. (Dental Materials and Instruments, Vol. 1, p. 131)
(1982) reported the tooth surface treatment effect when a solution prepared by adding various metal chlorides to a citric acid aqueous solution with a concentration of 10% by weight to a concentration of 3fI% was used as a tooth surface treatment agent. However, when zinc chloride is used as the metal chloride, the adhesive strength to dentin is as low as 44 kg/am'';
It is said to be unsuitable as a tooth surface treatment agent.

Further, when ferric chloride is used, although it has excellent adhesion to dentin, it adsorbs iron ions and is colored brown, which is a problem from the aesthetic point of view after treatment. However, it is surprising that although the treatment agent of the present invention contains a high concentration of metal chloride, it does not stain dentin and significantly improves the tooth surface treatment effect without impairing aesthetics. Note that if the concentration of metal chloride exceeds 50% by weight, the etching effect will be insufficient.

By adding a viscosity modifier to the tooth surface treatment agent of the present invention, it has fluidity when applied to the tooth surface, but quickly loses its fluidity (thixotropic property) after application, so that it can be locally applied. It is also possible to enable coating. Furthermore, the application site can be easily identified by coloring with food coloring or the like. Examples of such viscosity include polymeric thickeners typified by polyvinylpyrrolidone, carboxymethyl cellulose, and highly dispersible silica. Moreover, food coloring etc. are mentioned as a coloring material.

Hereinafter, the tooth surface treatment agent of the present invention will be specifically explained with reference to Examples.

(Example) Examples 1 to 16 Using various organic carboxylic acids and metal chlorides, Table 1
A tooth surface treatment agent with the following composition was prepared. The tooth surface treatment agent is 1
A predetermined amount of an organic carboxylic acid and water were placed in a 00m12 beaker, and a predetermined amount of metal chloride was added and thoroughly stirred to prepare a transparent liquid. Similarly, processing agents having the compositions shown in Table 1 were prepared as comparative examples. The adhesion force of the dental composite to the tooth substance when each treatment agent was used was measured by the method described below, and the tooth surface treatment effect was examined.

[Method for Measuring Adhesion Strength] Immediately after extraction, the labial side of a freshly frozen middle anterior tooth was polished with silicone carbide paper to create a smooth enamel or dentin surface. A spacer with a hole of a defined area was placed on the surface.

A tooth surface treatment agent adjusted to a predetermined concentration was applied to the enamel or dentin surface in the hole, left for 40 seconds, washed with water, and dried with air flow. A phosphate ester bonding material for dental composite resin (product name: Clearfil Photobond, manufactured by Kuraray Co., Ltd.) is applied to the surface, left for 30 seconds, volatile components are evaporated with an air stream, and a light irradiator (quick) is applied. Light (manufactured by Morita Seisakusho) was used for irradiation with light for 20 seconds for polymerization. A dental composite resin (trade name: Clearfil Photo Posteria, manufactured by Kuraray Co., Ltd.) was filled into the hole, and was polymerized and cured by irradiation with light for 60 seconds using the above-mentioned light irradiator. After removing the spacer, a stainless steel rod was adhesively fixed onto the hardened Funposit resin using a phosphate ester dental adhesive cement (Panavia, manufactured by Kuraray). After being stored in water at 37°C for 24 hours, 2 mm was measured using a universal testing machine.
The tensile adhesive strength was measured at a speed of 15). In addition, we made sure that there would be no breakage between the hardened composite resin and the stainless steel rod.

[Tooth surface treatment effect] The treatment agent according to the present invention exhibits excellent adhesive strength to both enamel and dentin. On the other hand, although the treatment agent of the comparative example had a high adhesion force to enamel, its adhesion force to dentin was insufficient. Further, when comparing the effects of the processing agents of Example 5 and Comparative Example 2 on the degeneration of fullerogen fibers derived from bovine dental pulp using electron micrographs, it was found that the effects of the processing agents of Example were small.

Table 1 (Effects of the Invention) According to the present invention, a tooth surface treatment agent capable of treating both the enamel surface and the dentin surface could be obtained.

Patent applicant RiRashi Co., Ltd.

Claims (3)

[Claims] (1) A tooth surface treatment agent for treating enamel and/or dentin surfaces, which comprises an organic carboxylic acid or its anhydride, metal chloride, and water, and (a) the organic carboxylic acid. or its anhydride has a concentration of 5 to 50% by weight based on the composition consisting of an organic carboxylic acid or its anhydride, a metal chloride, and water; (b) the metal chloride is potassium chloride, calcium chloride; or a mixture thereof, the concentration of which is 5% relative to the composition.
A tooth surface treatment agent characterized in that the amount is 50% by weight. (2) The tooth surface treatment agent according to claim 1, wherein the organic carboxylic acid is citric acid, succinic acid, oxalic acid, tartaric acid, ethylenediaminetetraacetic acid, or a salt thereof. (3) The tooth surface treatment agent according to claim 1, wherein each of citric acid and calcium chloride is contained in an amount of 5 to 30% by weight based on the composition.