JP2566676B2 - Dental composition - Google Patents

Description

TECHNICAL FIELD The present invention relates to a dental composition used as a cleaning / disinfecting agent for dentin or root canals in the field of dentistry.

(Prior Art) A sodium hypochlorite aqueous solution is used for cleaning and disinfecting the dentin surface and root canal from which caries have been ground and removed in dental treatment.

(Problems to be Solved by the Invention) However, since the conventionally used sodium hypochlorite aqueous solution has a low viscosity, it was difficult to apply the solution only to a desired place. That is, even if the sodium hypochlorite aqueous solution is applied to a part of the tooth surface,
The liquid spreads around the target area, so the amount required for cleaning and disinfection cannot be secured in that area,
Alternatively, there is the inconvenience that the flowing out aqueous solution attacks the soft tissue in the vagina of the mouth.

In addition, we conducted a study focusing on the fact that the cleaning / disinfecting effect of sodium hypochlorite is due to its oxidative effect, and found that the same cleaning / disinfecting effect can be obtained by using metal salts of related elements that have similar effects. It became clear that
It was confirmed that the hypochlorite need not be limited to the sodium salt.

Therefore, an object of the present invention is to provide an alkali metal hypochlorite preparation which can be applied only to a required site in a limited manner.

(Means for Solving the Problems) By the way, in order to solve the above problems, a thickener may be added to an aqueous solution of an alkali metal hypochlorite, but when actually examined, a water-soluble organic polymer or colloidal silica is used. Typical thickeners such as are not practical because they cannot withstand the strong alkaline and strong oxidizing properties of the aqueous solution of alkali metal hypochlorite or accelerate the decomposition of alkali metal hypochlorite. I understand. Therefore, in order to find a thickener satisfying these conditions, in particular, intensive studies were carried out on inorganic compounds, and as a result, aluminum oxide fine particles were found to be excellent in thickening effect and storage stability, and the present invention was completed. Came to.

That is, the present invention is a dental composition characterized by having an alkali metal hypochlorite, water and BET specific surface area of 10 m ² / g or more of aluminum oxide fine particles as a main component, and having a viscosity of 50 centipoise or more. is there.

The composition of the present invention is prepared by using an alkali metal hypochlorite salt as an aqueous solution and uniformly dispersing aluminum oxide fine particles therein. Examples of the alkali metal hypochlorite used in the present invention include lithium salt, sodium salt, potassium salt, and cesium salt. Among them, sodium salt and potassium salt are preferable from the viewpoint of stability. The cleaning / disinfecting effect on the dentin and the root canal is uniquely dependent on the concentration of alkali metal hypochlorite in the aqueous solution of alkali metal hypochlorite, and the preferred concentration of the present invention is 0.1 to 2
It is 0% by weight. Incidentally, alkali hydroxide represented by sodium hydroxide is added as a stabilizer to an aqueous solution of alkali metal hypochlorite which has been conventionally used for the purpose of sterilization and bleaching. The aqueous solution of the alkali metal hypochlorite in the present invention also contains 1 to 20% by weight of alkali hydroxide such as sodium hydroxide as a stabilizer as in the conventional case.
It is preferably added.

The aluminum oxide fine particles used in the present invention have a BET specific surface area of 1 as a thickener for an aqueous solution of alkali metal hypochlorite.
Those of 0 m ² / g or more are used. The shape of the aluminum oxide fine particles does not affect the effect of the present invention, and any shape such as granular, needle-like, fibrous or plate-like may be used. Therefore, the term "fine particles" in the present invention is used as a general term for the above shapes.

The reason why the aluminum oxide fine particles are required as a thickener for the alkali metal hypochlorite aqueous solution is a condition of the thickener, that the thickener does not accelerate the decomposition of the alkali metal hypochlorite salt, This is because the thickener simultaneously satisfies the two points that it is stable against the oxidizing action of the alkali metal hypochlorite aqueous solution and strong alkalinity.

Conventionally, a water-soluble organic polymer or colloidal silica is generally used as a thickener for an aqueous solution. For example, an aqueous acid solution of phosphoric acid, citric acid, etc., which is used as a tooth surface acid treating agent in dental treatment, is a water-soluble organic polymer such as polyvinyl alcohol, polyvinylpyrrolidone, polyethylene glycol, carboxymethyl cellulose sodium salt, or colloidal silica. Is thickened with.

When an aqueous solution of an alkali metal hypochlorite was thickened with a water-soluble organic polymer in the same manner as described above, a viscosity increase was observed immediately after the preparation, but the polymer was formed by the oxidizing action or strong alkalinity of the aqueous solution of the alkali metal hypochlorite. Was denatured and decomposed, and its viscosity could not be maintained.

On the other hand, many experiments were conducted using silica, aluminum oxide, and other inorganic fine particles resistant to an alkaline aqueous solution as a thickener for an aqueous alkali metal hypochlorite solution. Were found to accelerate the decomposition of alkali metal hypochlorite. That is, despite unexpected findings,
It has been clarified that only aluminum oxide can be used as a thickener for an aqueous solution of alkali metal hypochlorite.

By adding aluminum oxide fine particles selected for such a reason to an aqueous solution of an alkali metal hypochlorite to form a paste, the object of the present invention can be achieved, even if the composition is applied to a vertical surface. It does not run off under its own weight when the viscosity of the composition is 50 centipoise or more. Therefore,
The addition amount of the aluminum oxide fine particles to the aqueous solution of alkali metal hypochlorite is selected so that the viscosity of the composition is 50 centipoise or more, more preferably 100 centipoise or more. The relationship between the added amount of aluminum oxide fine particles and the viscosity of the composition cannot be generally stated because the size of the specific surface area of aluminum oxide is also involved, but a composition of 50 centipoise or more, for example, BET specific surface area of 100 m ² / g oxidation Obtained by adding 12 parts by weight of aluminum fine particles to 100 parts by weight of an aqueous solution of alkali metal hypochlorite (152 centipoise), or by adding 100 parts by weight of aluminum oxide fine particles having a BET specific surface area of 14 m ² / g (50 centipoise). . Aluminum oxide fine particles having a BET specific surface area of less than 10 m ² / g are extremely inferior in the thickening effect, and the precipitation of the aluminum oxide fine particles is very likely to occur, so that a practical composition cannot be obtained. For example, even if 100 parts by weight of aluminum oxide fine particles having a BET specific surface area of 6 m ² / g is added to 100 parts by weight of an aqueous solution of an alkali metal hypochlorite solution, it does not exceed 50 centipoise. If the amount of addition is further increased, a composition with high viscosity can be obtained inevitably, but if this composition is left to stand, layer separation will occur in a short time. Moreover, since the content of the alkali metal hypochlorite is relatively decreased when the added amount of aluminum oxide is increased, the effect of cleaning and disinfecting the teeth, which is the original purpose of the composition, may be reduced. There is. Therefore, as the aluminum oxide fine particles, the BE
A T specific surface area of 10 m ² / g or more, more preferably 50 m ² / g or more is used.

As described above, aluminum oxide fine particles having a BET specific surface area of 10 m ² / g or more are selected as a thickener for an aqueous solution of an alkali metal hypochlorite salt, and the fluidity is obtained by adding it so that the viscosity becomes 50 centipoise or more. It is possible to obtain an alkali metal hypochlorous acid salt formulation in which the amount is suppressed, and the object of the present invention can be achieved.

In addition, in order to make it easy to identify the application of the composition, a small amount of an inorganic pigment such as iron oxide may be added and colored.

(Effects of the Invention) The dental composition of the present invention is an alkali metal hypochlorite preparation whose fluidity is suppressed by the addition of a thickener, and is applied to the outside of the applied portion when cleaning the dentin or the root canal. It has the effect of suppressing the occurrence of troubles such as invading the soft tissue in the vagina of the mouth. Further, the composition has a great advantage not only in cleaning and disinfecting the dentin and the root canal but also in the handling property that it does not spread and spread even when cleaning the surface of the dental restorative material.

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to the examples.

(Examples) Examples 1 and 2 and Comparative Examples 1 to 6 Compositions comprising 100 parts by weight of 10% by weight sodium hypochlorite aqueous solution, 10 parts by weight of aluminum oxide having a granular and BET specific surface area of 100 m ² / g, and 10 A composition comprising 100 parts by weight of an aqueous solution of sodium hypochlorite in a weight ratio of 100 parts by weight, 100 parts by weight of aluminum oxide having a BET specific surface area of 10 m ² / g was prepared and stored at 37 ° C. for 4 days. Changes in the amount of sodium hypochlorite before and after storage were quantified by a titration method to calculate the residual ratio of sodium hypochlorite after storage, which were taken as Examples 1 and 2, respectively. The results are shown in Table 1.

To 100 parts by weight of 10% by weight sodium hypochlorite aqueous solution,
Silica (BET specific surface area 380 m ² / g), titanium dioxide (BET specific surface area 50 m ² / g), magnesium silicate (BET specific surface area 3 m ²
/ g), barium carbonate (BET specific surface area 5 m ² / g), or zirconium dioxide (BET specific surface area 50 m ² / g) was added to 10 parts by weight to prepare a composition at 37 ° C. as in Examples 1 and 2. After storage for 4 days, the residual rate of sodium hypochlorite was determined, and the results are shown in Table 1 as Comparative Examples 1 to 5, respectively. A 10% by weight aqueous solution of sodium hypochlorite alone was used as in Examples 1 and 2.
It was stored at 37 ° C. for 4 days and the residual rate of sodium hypochlorite was determined. The result is Comparative Example 6 and the results are shown in Table 1.

It is clear from Table 1 that only aluminum oxide does not accelerate the decomposition reaction of sodium hypochlorite.

Example 3 and Comparative Examples 7 to 9 A composition comprising 100 parts by weight of a 10% by weight potassium hypochlorite aqueous solution, 10 parts by weight of aluminum oxide having a granular and BET specific surface area of 100 m ² / g was prepared and stored at 37 ° C. for 4 days. did. A change in the amount of potassium hypochlorite before and after storage was quantified by a titration method to calculate the residual ratio of potassium hypochlorite after storage, and Example 3
And The results are shown in Table 2.

100 parts by weight of 10% by weight potassium hypochlorite aqueous solution, silica (BET specific surface area 380 m ² / g), or titanium dioxide (BE
10 parts by weight of T specific surface area 50 m ² / g) was added to prepare a composition,
It was stored at 37 ° C. for 4 days in the same manner as in Example 3, and the residual ratio of potassium hypochlorite was determined. The results are shown in Table 2 as Comparative Examples 7 to 8, respectively. The 10% by weight potassium hypochlorite aqueous solution alone was stored at 37 ° C. for 4 days in the same manner as in Example 3 to determine the residual rate of potassium hypochlorite. The results are shown in Table 2 as Comparative Example 9.

It is clear from Table 2 that aluminum oxide alone does not accelerate the decomposition reaction of potassium hypochlorite.

Example 4 The viscosity of the composition prepared in Example 1 was measured with an E-type viscometer (Tokyo Keiki Co., Ltd.) and found to be 152 centipoise.
The composition was stored at 37 ° C. for 4 days, but no change in viscosity was observed before and after storage.

Comparative Example 10 25% by weight of 100 parts by weight of 10% by weight sodium hypochlorite aqueous solution
Weight% polyvinyl alcohol (degree of polymerization 1700, degree of suspension 98.5
When 50 parts by weight of (mol%) aqueous solution was dissolved, the viscosity increased to 51 centipoise immediately after preparation, but the increased viscosity disappeared after 1 day at room temperature.

Examples 5 to 11 and Comparative Examples 11 to 13 Aluminum oxide having different particle shapes and BET specific surface areas as shown in Table 3 was mixed with 100 parts by weight of a 10% by weight aqueous solution of sodium hypochlorite to prepare 9 kinds of compositions. Was prepared.
The viscosity of the obtained composition was measured with an E-type viscometer (Tokyo Keiki). In addition, the dentin surface (plane) exposed by grinding and removing the enamel of the human molar is held parallel to the vertical line,
The composition was applied to this surface, and it was observed whether the state where the composition was applied was maintained or whether the composition flowed down by its own weight.

Regardless of the particle shape, those with a specific surface area of 10 m ² / g or more could effectively thicken. Also, it is clear that a composition having a viscosity of less than 50 centipoise will run off under its own weight.

Claims (1)

(57) [Claims] 1. An alkali metal hypochlorite salt, water and BET.
A dental composition comprising aluminum oxide fine particles having a specific surface area of 10 m ² / g or more as a main component and a viscosity of 50 centipoise or more.