JP2009263268A - Composition for reforming tooth interprismatic space - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a composition which corresponds also to endogenous discoloration wherein the color of dentin is discolored due to aging, an external wound or the like can be seen through enamel, and gives a beautiful bleaching effect to teeth. <P>SOLUTION: The composition for reforming tooth enamel surface layer interprismatic spaces contains 0.05 to 18 mass% of phytic acid or its salt and has pH of 5.5 to 6.5, when diluted with water into concentration of 30 mass%. Light reflected from the inside of enamel is increased by the scattering of the light in interprismatic spaces to give naturally white teeth. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a composition for remodeling the trabecular space of teeth.

  The coloring of human teeth can be exogenous coloring, such as calculus, plaque, smoking, or customary eating and drinking such as coffee or tea, and the color of dentin colored by aging or trauma. Depends on intrinsic coloring, such as when the enamel is visible through the enamel or when the enamel is colored by the use of a drug such as tetracycline during the tooth formation. Therefore, in order to fundamentally whiten teeth, it is necessary to deal with not only exogenous coloring but also intrinsic coloring.

  Conventionally, various physical or chemical methods have been reported as means for whitening teeth. As a physical method, in addition to polishing removal, n-butyl ether, butyl butyrate, or the like is used to remove the colored material (Patent Document 1, Patent Document 2), or a ceramic veneer is used to coat the teeth. There are ways to improve color tone. As chemical methods, a method for promoting remineralization with an oral composition containing hydroxyapatite (Patent Document 3, Patent Document 4), an oxidative bleaching method using a peroxide (Patent Document 5), A method using a tooth whitening composition in which a self-curing calcium phosphate compound and a fluorine compound are mixed with an oxide (Patent Document 6), and an oral composition containing a liquefied calcium phosphate compound promotes remineralization of enamel. A method (Patent Document 7) and the like are known.

  However, the method using ceramic veneer or the like needs to delete the tooth substance, and the use of this method requires guidance and treatment by a dentist. In addition, the method of oxidative bleaching using a peroxide requires the use of a high-concentration peroxide capable of oxidative bleaching of the teeth, and therefore needs to be performed carefully in accordance with the guidance of an expert. However, even under the guidance of specialists, damage to teeth and gums and hypersensitivity may occur due to peroxides.

On the other hand, the method of promoting tooth remineralization using calcium phosphate compounds such as hydroxyapatite mainly makes the teeth healthy by repairing the enamel surface with apatite. I can't say.
JP-A-1-203316 JP-A-1-104004 JP-A-1-305020 JP-A-9-202718 Japanese Patent Publication No. 6-8248 JP-A-11-116421 JP-A-8-319224

  An object of the present invention is to provide a composition that gives an excellent whitening effect to teeth.

The enamel of a tooth is made up of a collection of columnar bodies made of hydroxyapatite polycrystals called enamel trabeculae. In general, in the youth, a space (gap), that is, a trabecular space exists between the enamel trabeculae and the enamel trabeculae, and is filled with water, saliva components, and the like. In such a tooth, the incident light to the enamel is scattered due to a large difference in refractive index between the enamel trabeculae and the space between the trabeculae, and the teeth appear white.
However, if the substance dissolved in saliva continues to accumulate in the trabecular space of the tooth enamel surface, for example due to aging, the trabecular space is filled, and as a result, the refractive index of the enamel trabecular space is smaller than that of the trabecular space. As the difference becomes smaller, the enamel becomes more transparent and incident light tends to reach the dentin, which is yellow or brown, located deep in the enamel, and the teeth appear yellow.
Therefore, the present inventors have formed enamel by selectively removing from the trabecular space a material (hereinafter referred to as “trabecular space material”) present in the trabecular space of the tooth enamel surface layer. By re-forming the trabecular gap while suppressing damage to the enamel trabecula itself, and increasing the reflected light from the inside of the enamel by light scattering by the space of the trabecular gap, natural white teeth can be obtained Thought.
Further, as a result of various studies, it was found that phytic acid has an action of re-forming the lost trabecular space, and the present invention has been completed.

That is, the present invention contains 0.05 to 18% by mass of phytic acid or a salt thereof, and re-forms the trabecular space of a tooth having a pH of 5.5 to 6.5 when diluted to 30% by mass with water. The composition for use is provided.
Moreover, this invention contains 0.05-18 mass% of phytic acid or its salt, and when diluted to 30 mass% with water, the composition for oral cavity whose pH is 5.5-6.5 is used for a tooth | gear. A method for removing a trabecular bone material of a tooth is provided.

  When the composition of the present invention is applied to teeth, the trabecular space material generated by aging and the like is selectively removed, and the lost trabecular space is re-formed. Preventing or whitening teeth from inside the teeth. In addition, it is possible to obtain a high whitening effect on the intrinsic coloring of the tooth while suppressing damage to the enamel of the tooth. Thereby, it is possible to easily whiten teeth through repeated use such as daily oral care or regular use of chewing gum.

The active ingredient of the composition for remodeling the trabecular cavity of the present invention is phytic acid or a salt thereof. Phytic acid is also called myo-inositol hexaphosphate and is a phosphate compound. Among various phosphoric acid compounds, phytic acid or a salt thereof is particularly excellent when considering both the remodeling action of trabecular space and damage to enamel.
Examples of the salt include alkali metal salts such as sodium and potassium, ammonium salts, and the like.

The trabecular cavity re-forming composition of the present invention contains phytic acid or a salt thereof in an amount of 0.05% by mass to 18% by mass.
From the viewpoint of sufficiently exerting the trabecular space re-forming effect of the present invention, phytic acid or a salt thereof is contained in the composition in an amount of 0.05% by mass or more, preferably 0.1% by mass or more. From the viewpoint of suppressing decalcification and from the viewpoint of taste and squeakiness, the content is 18% by mass or less, preferably 10% by mass or less. In addition, the content of phytic acid or a salt thereof in the composition for re-forming the trabecular space of the present invention is measured by neutralizing with potassium hydroxide or sodium hydroxide, and the total amount is converted to an acid.

The trabecular cavity re-forming composition of the present invention has a pH of 5.5 to 6.5 when diluted to 30% by mass with water.
That is, when the composition is applied to the oral cavity, the trabecular crevice material is removed, the decalcification of the tooth surface is suppressed, and the formation of irregularities on the tooth surface is suppressed, that is, the trabecular crevice material is selected. From the viewpoint of removal, the pH when the composition is diluted to 30% by mass with water is preferably 5.5 or more, more preferably 5.8 or more, and the light scattering effect due to the formation of the trabecular space is sufficient. From the viewpoint of achieving the above, it is preferable that the pH is 6.5 or less, more preferably 6.2 or less.
Since the pH cannot be accurately measured in the case of a highly viscous oral composition such as toothpaste, the pH of the composition is determined by diluting the composition to 30% by mass with water. . What was diluted to 30% by mass with water was assumed to be applied to the oral cavity of the composition.
In order to adjust the pH of the composition to the above range, it is preferable to use a pH adjusting agent, and the pH adjusting agent can suppress decalcification of teeth without inhibiting the trabecular space re-forming effect by phytic acid. In range, organic acid salts such as acetic acid, fumaric acid, malic acid, lactic acid, gluconic acid, tartaric acid, phosphoric acid other than phytic acid (for example, orthophosphoric acid), inorganic acid salts such as hydrochloric acid, sulfuric acid, sodium hydroxide, etc. Examples include hydroxides, ammonia or aqueous ammonia, lower alkanolamines, basic amino acids such as arginine and lysine, and these may be used alone or in combination of two or more.

  In the trabecular cavity re-forming composition of the present invention, the content of polyvalent cations is preferably kept low. This is because the polyvalent cation makes phytic acid insoluble or reduces the effect of removing the trabecular crevice substance, thereby preventing the reduction of the effect. The content is preferably 100 ppm or less as measured by ICP emission analysis (ICP emission analyzer: Optima 5300DV, manufactured by Perkin Elmer). That is, it is desirable not to add an agent that mainly supplies polyvalent cations such as aluminum, calcium, magnesium, iron, and zinc, and those that substantially do not contain polyvalent cations are preferable.

  Further, the composition for remodeling the trabecular space of the present invention includes sodium fluoride, potassium fluoride, and the like within a range (content, dosage form, etc.) that does not inhibit the remodeling effect of the trabecular space by phytic acid or a salt thereof. Fluoride such as ammonium fluoride and sodium monofluorophosphate may be blended. The fluoride is preferably contained in the composition in an amount of 0.01 to 0.5% by mass, and more preferably 0.02 to 0.2% by mass.

  In addition to the above components, the composition for re-forming the trabecular space of the present invention includes, for example, a foaming agent, a foaming aid, an abrasive, a wetting agent, a thickening agent, a gelling agent, a binder, a bulking agent, and a sweetening agent. In addition, preservatives, bactericides, medicinal ingredients, pressure-sensitive adhesives, pigments, dyes, fragrances and the like can be appropriately contained, and the composition can be produced by conventional methods according to various dosage forms. Moreover, combined use, such as polyethylene glycol which is a conventionally used whitening component, is not limited.

The trabecular cavity re-forming composition of the present invention is prepared in a dosage form such as a solution, gel, or paste, for example, powder dentifrice, moisturizing dentifrice, toothpaste, liquid dentifrice, mouthwash, etc. Can be used as a food composition such as chewing gum, troche, candy, etc., or can be used as an oral hygiene device such as dental floss.
In any of these dosage forms, polyethylene glycol, propylene glycol, glycerin, sorbitol, maltitol, xylitol, lactitol, erythritol and the like can be contained for the purpose of a wetting agent or a thickening agent.

Further, as a thickening agent for a solution-like composition or a gelling agent for a gel-like composition, and as a binder for a paste-like composition, sodium carboxymethylcellulose, hydroxyethylcellulose, carboxyvinyl polymer, xanthan gum, carrageenan, alginic acid Sodium, hydroxypropyl cellulose, guar gum, sodium chondroitin sulfate and the like can be contained alone or in combination. Among these, it is preferable to select an adhesive other than sodium alginate from the viewpoint of sufficiently exerting the whitening effect of phytic acid or a salt thereof.
In particular, in the case of a high salt concentration due to the buffer system, one or more kinds of nonionic polymers, that is, hydroxyethyl cellulose, guar gum, hydroxypropyl cellulose and the like can be contained.

Such a trabecular cavity re-forming composition is applied to human teeth for 10 seconds to 10 hours (10 seconds or more for mouthwashes, 1 minute or more for dentifrices, 5 minutes or more for applicators) ), For example, once to 5 times a day, preferably 1 to 16 weeks, by selectively removing trabecular interstitial material from the trabecular space to the enamel trabecules themselves forming the enamel Natural white teeth can be obtained by re-forming the trabecular space while suppressing damage and increasing the reflected light from the enamel through the space of the trabecular space. That is, even when used for a long time or repeatedly, natural white teeth can be obtained while suppressing damage to the enamel trabecules themselves.
In order to apply the composition for oral cavity of the present invention to teeth, it may be applied as it is, or includes both cases in which the composition is diluted to about 30% by mass with water or saliva. That is, in the case of a mouthwash, it is applied to teeth without dilution. On the other hand, in the case of a toothpaste, etc., it is applied to the teeth in a state diluted to about 30% by mass with saliva.

Test Example 1: Selection of Phosphate Compound Table 1 shows each component of a toothpaste containing 1% phytic acid and its content (Example 1). A toothpaste mixed with these components was prepared as a test solution. Magnesium and aluminum in the test solution were 100 ppm or less as measured by ICP emission analysis (ICP emission analyzer: Optima 5300DV manufactured by Perkin Elmer).
Each test solution with the same components and mixing ratios as in Example 2 except that phytic acid in the toothpaste in Example 2 in Table 1 was replaced with orthophosphoric acid, pyrophosphoric acid, polyphosphoric acid, and metaphosphoric acid, respectively. Was prepared.
The human tooth used for the test is a sample in which a part of the enamel surface is polished into a mirror surface to be a treated surface, and the other part is coated with wax.
Human teeth were immersed in each test solution for 48 hours at room temperature. In this case, a change Δb ^* in b ^* value before and after immersion was measured. The change [Delta] b ^* is - was determined from (after immersion b ^* before immersion b ^*).
This b ^* value is calculated using the L ^* a ^* b ^* color system for images taken using a digital camera D1x (Nikon) and a white flash light source (Konica Minolta) using Adobe Photoshop (Adobe Systems). Represented and sought. The closer the value of b ^* is to 0, the less yellowish the whiteness increases, and the larger -Δb ^* (Δb ^* absolute value) means the whiteness increases.
The damage to the enamel trabeculae of the teeth was evaluated by visually observing the irregularities of the tooth surface state with a magnifying glass (magnification 10 times).
The results of Test Example 1 are shown in Table 2.

Although pyrophosphoric acid, polyphosphoric acid, and metaphosphoric acid are observed to have some b * value change (Δb *) and have a whitening effect, surface observation reveals deep irregularities in the enamel trabecula and damage is observed. It was. For orthophosphoric acid, almost no damage to the enamel trabeculae was observed, but Δb * was small and a sufficient whitening effect was not recognized. On the other hand, phytic acid has a large Δb * value, and a high trabecular space substance removal effect is recognized. Moreover, the surface of the enamel trabecular remains smooth before and after the test solution treatment, and no change is observed. No damage was found. Tripolyphosphoric acid, tetrapolyphosphoric acid, hexapolyphosphoric acid, and pentapolyphosphoric acid were also performed in the same manner, but phytic acid was remarkably superior in removing the trabecular space material.
Accordingly, phytic acid was most excellent in the whitening effect and the evaluation of damage to the enamel trabeculae among these phosphate compounds. Furthermore, the following tests were conducted on test solutions containing phytic acid.

Test Example 2: Composition pH and Phytic Acid Content in Composition (1) Preparation of Composition and Test Object Tables 1 and 3 show the toothpastes of Examples 1-7 and Comparative Examples 1-8. Each component and its content are shown. The pH of these toothpastes (test solutions) is the pH when diluted to 30% by mass with water.
When the content of phytic acid in the toothpaste is 1% by mass and the pH is diluted to 30% by mass with water, 3.0, 4.0, 5.0, 5.5, 6.0, Toothpaste test solutions (Examples 1 to 3 and Comparative Examples 1 to 5) adjusted to 6.5, 7.0, and 8.0 were prepared. The content of magnesium and aluminum in each of these test solutions was 100 ppm or less.
In addition, each test solution of toothpaste with a phytic acid content in the toothpaste adjusted to 0, 0.05, 0.1, 10, 18, 19, 20% by mass and the pH adjusted to 6.0 (Examples 4 to 7 and Comparative Examples 6 to 8) were prepared. A phytic acid content of 1% by mass was intended for Example 2. The contents of magnesium and aluminum in each test solution were also 100 ppm or less.
The measurement of b ^* value change Δb ^* before and after immersion with each test solution, the measurement of unevenness of the tooth surface state, and the observation of the trabecular space state by SEM are the same as in Test Example 1 above. I went there.

(2) Method for observing tooth trabecular gap of SEM by electron microscope (SEM: Hitachi S-4800) before and after applying toothpaste (test solution) of Example 2 to human teeth. The observed photographs are shown in FIGS. 2 (a) and 2 (b).

(3) Test method by paneler Further, the toothpaste of each composition was brushed with a paneler (20 healthy men and women) for 5 minutes in the morning and evening for 2 weeks. The age structure of healthy men and women at this time is 20 people in their 40s to 70s.

(4) Results (observation of trabecular space of teeth by SEM)
The photographs of the trabecular space of the teeth observed with an electron microscope (SEM: Hitachi S-4800) are shown in FIGS. FIG. 1 (a) shows a photograph of white teeth A (10th generation human teeth) observed with an electron microscope (SEM), and FIG. 1 (b) shows colored teeth B (50th generation human teeth). As shown in the photographs of FIGS. 1A and 1B, the trabecular space can be observed with the white teeth A, but the trabecular space can hardly be observed with the colored teeth B.
FIG. 2 (b) shows the tooth B before dipping in the composition containing phytic acid of the present invention, and FIG. 2 (a) shows that after dipping in the composition containing phytic acid of the present invention (Example 2). The photograph observed with the electron microscope of the tooth | gear B of is shown. As shown in the photographs of FIGS. 2 (a) and 2 (b), the trabecular space can hardly be observed in the photograph of FIG. 2 (b) before the immersion of the tooth B, but small in the photograph of FIG. 2 (a) after the immersion. The column gap was observed, and it was confirmed that a small column gap was formed.

(Test result at pH of composition)
Table 1 shows changes in the surface state due to immersion at each pH, and Tables 3 and 4 show changes in Δb ^* .

As shown in FIG. 3 and Table 4 (Tables 1 and 3), in the region where the pH is lower than 5.5, the change in b ^* (Δb ^* ) indicating the change in tooth whiteness is large, but the surface condition of the tooth Unevenness was observed, and in observation with an electron microscope (SEM), a gap wider than the trabecular gap (0.1 to 0.5 μm) of the original enamel trabecula was observed. Therefore, in the region lower than pH 5.5, whiteness of the teeth can be obtained, but it can be determined that the enamel trabeculae are dissolved and decalcified. On the other hand, when the pH was 7.0 or more, the change Δb ^* in tooth white after immersion was very small, but the surface condition was smooth and no change was observed. On the other hand, the trabecular cavity re-forming composition of the present invention has a pH of 5.5 or more and 6.5 or less. Under these conditions, Δb ^* is sufficiently large and exhibits high whitening performance. Appropriate gaps were observed between the enamel trabeculae, the surface state was smooth and no change was observed, and it was judged that almost no demineralization occurred.
Thus, the phytic acid (inositol 6-phosphate) and its salt in the region of pH 5.5 to 6.5 shown in the present invention hardly damage the enamel trabeculae constituting the enamel, The trabecular space material can be selectively removed.

(Test results for the content of phytic acid in the composition)
FIG. 4 and Table 5 (Tables 1 and 3) show Δb ^* by phytic acid concentration. FIG. 4B is an enlarged view of Δb ^* in a region where the phytic acid concentration is 1.5% by mass or less. As shown in FIG. 4 (b) and Tables 1 and 3, even when the phytic acid concentration was 0.05% by mass, the b ^* value change Δb ^* was −4.5, indicating whitening performance, and at 0.1% or more, Δb ^* Showed the highest whitening performance.
However, as shown in FIG. 4A, almost no change in the surface state is observed up to a phytic acid concentration of 18% by mass, but unevenness occurs at a concentration of 19% by mass or more. Moreover, also from a viewpoint of taste, the density | concentration of 18 mass% or less and also the density | concentration of 10 mass% or less are preferable.

  Therefore, the trabecular space re-forming composition using phytic acid at a concentration of 0.05 to 18% by mass at a pH in the range of 5.5 to 6.5 has a good feeling and hardly damages teeth or gums. High whitening performance without giving.

It is a SEM observation photograph of (a) white tooth A and (b) colored tooth B. (A) Tooth B after immersion in a composition containing phytic acid, (b) SEM observation photograph of tooth B before immersion. The influence of the pH change of the composition containing phytic acid is shown. The influence of the phytic acid content in the composition is shown. (A) A region having a phytic acid content of 25% by mass or less and (b) a region having a phytic acid content of 1.5% by mass or less are shown.

Claims (2)

  A composition for remodeling the trabecular space of a tooth containing 0.05 to 18% by mass of phytic acid or a salt thereof and having a pH of 5.5 to 6.5 when diluted to 30% by mass with water.   A dental composition containing 0.05 to 18% by mass of phytic acid or a salt thereof and having a pH of 5.5 to 6.5 when diluted to 30% by mass with water is applied to the teeth. Removal method of column gap material.