阅读说明：本技术 口腔用组合物 (Oral composition ) 是由 内野阳介 松冈纯枝 于 2020-01-16 设计创作，主要内容包括：本发明涉及一种通过高含量的赤藓糖醇而有效地抑制由牙本质感觉过敏症引起的疼痛增强的口腔用组合物。即,本发明提供一种口腔用组合物,其含有以下成分(A)、(B)、(C)以及(D)：(A)赤藓糖醇6质量％以上33质量％以下、(B)氟化钠、(C)甘油磷酸钙、(D)水,并且,成分(A)的含量与成分(D)的含量的质量比((A)/(D))为0.06以上0.2以下。(The present invention relates to an oral composition which effectively suppresses the increase in pain caused by dentinal hypersensitivity by a high erythritol content. That is, the present invention provides an oral composition comprising the following components (a), (B), (C) and (D): (A) erythritol 6-33 mass%, (B) sodium fluoride, (C) calcium glycerophosphate, and (D) water, wherein the mass ratio ((A)/(D)) of the content of component (A) to the content of component (D) is 0.06-0.2.)

1. An oral composition comprises a mixture of a first active agent,

comprises the following components (A), (B), (C) and (D):

(A) erythritol of 6 to 33 mass%,

(B) Sodium fluoride,

(C) Calcium glycerophosphate,

(D) The amount of water is controlled by the amount of water,

the mass ratio (A)/(D) of the content of the component (A) to the content of the component (D) is 0.06 to 0.2.

2. The oral composition of claim 1,

the content of the anionic surfactant is less than 1% by mass.

3. The oral composition of claim 1 or 2,

the content of the component (D) is 55 to 93 mass%.

4. The oral composition according to any one of claims 1 to 3,

the mass ratio Ca/F of the amount of calcium atoms in the component (C) to the amount of fluorine atoms in the component (B) is 0.35 to 0.55.

5. The oral composition according to any one of claims 1 to 4,

the total content of the fluorine compound and the polyvalent metal salt other than the component (B) is less than 0.02% by mass.

6. The oral composition according to any one of claims 1 to 5,

the pH value at 25 ℃ is 5.0 to 10.0.

7. The oral composition according to any one of claims 1 to 6,

the content of the component (B) is 0.1 to 2.5 mass%.

8. The oral composition according to any one of claims 1 to 7,

the content of the component (C) is 0.1 to 5% by mass.

9. The oral composition according to any one of claims 1 to 8,

can be used for treating dentin hypersensitiveness.

Technical Field

The present invention relates to an oral composition.

Background

Conventionally, oral compositions using various components such as abrasives, foaming agents, or bactericides have been developed, which are effective for preventing oral diseases such as dental caries, periodontal disease, and halitosis by suppressing the formation of a biofilm in the oral cavity and removing the formed biofilm.

Among such components, erythritol is known to be an effective component in suppressing or decomposing an aggregation reaction between bacteria in the oral cavity, and is known to be excellent not only in the effect of suppressing the formation of a biofilm but also in the effect of removing a biofilm formed in a gap between a tooth and a tooth or a periodontal pocket, as described in patent document 1, for example. In addition, in the dentifrice composition described in patent document 2, the removal effect of biofilm in the oral cavity is further improved by setting the erythritol content to a high level.

(patent document 1) Japanese patent laid-open No. 2005-29484

(patent document 2) Japanese patent laid-open No. 2012-36172

Disclosure of Invention

The present invention provides an oral composition comprising the following components (a), (B), (C) and (D):

(A) erythritol of 6 to 33 mass%,

(B) Sodium fluoride,

(C) Calcium glycerophosphate,

(D) The amount of water is controlled by the amount of water,

the mass ratio ((A)/(D)) of the content of the component (A) to the content of the component (D) is 0.06 to 0.2.

The present inventors have found that, if erythritol having excellent effects of inhibiting biofilm formation in the oral cavity and removing erythritol is used at a high content as in the above patent documents, pain caused by dentinal hypersensitivity is increased due to osmotic pressure stimulation in which erythritol is dissolved in water.

Thus, there is a strong demand for an oral composition which contains erythritol at a high content and has an excellent effect of inhibiting the formation of an intraoral biofilm or an excellent effect of removing the erythritol, and which can effectively prevent pain caused by dentinal hypersensitivity.

Accordingly, the present inventors have conducted various studies and as a result, have found that an oral composition which can effectively reduce the osmotic pressure stimulation mainly caused by erythritol, efficiently form a coating film of fluoride such as calcium fluoride which effectively blocks the openings of dentinal tubules in the surface of exposed dentin, and effectively prevent the increase in pain caused by dentinal hypersensitivity can be obtained by using a combination of erythritol in a high content and erythritol in a specific mass ratio with sodium fluoride and calcium glycerophosphate.

That is, the present invention relates to an oral composition which can effectively suppress the increase of pain caused by dentinal hypersensitivity by a high erythritol content.

According to the oral composition of the present invention, although the content of erythritol is high, the osmotic pressure stimulation due to erythritol can be reduced, and the openings of the dentinal tubules in the surface of the exposed dentin are effectively and effectively blocked by the fluoride coating, so that the excellent effect of suppressing the pain caused by dentin hypersensitivity can be sufficiently exhibited. Therefore, even with a high erythritol content, excellent effects of inhibiting the formation of an intraoral biofilm and removing the biofilm can be sufficiently enjoyed.

Drawings

Fig. 1 is an electron micrograph of the surface of dentin when the oral composition of example 3 was used.

Fig. 2 is an electron micrograph of the surface of dentin when the oral composition of comparative example 2 was used.

Detailed Description

The present invention will be described in detail below.

In the present invention, the "dentinal tubules" are also referred to as "dentinal tubules". The term "occlusion of dentinal tubules" means physically occluding the dentinal tubules, and includes not only a state in which the surface of dentin covers the opening or the periphery of the opening of the dentinal tubules, but also a state in which the dentinal tubules are filled in and covered (plugged) in tubules near the surface of the dentinal tubules.

In the present invention, "fluoride" mainly refers to a fluorine-containing inorganic compound such as calcium fluoride formed from the component (B) and the component (C), and a coating of fluoride is also referred to as a "fluoride coating".

The oral composition of the present invention contains erythritol as component (a) in an amount of 6 to 33 mass%. This promotes the formation of a fluoride coating film by the component (B) and the component (C) described later, and the fluoride coating film effectively physically blocks dentinal tubules, thereby exhibiting the effect of suppressing pain caused by dentinal hypersensitivity. Further, the original effect of erythritol, that is, the biofilm formation-inhibiting effect or the biofilm-removing effect can be exhibited by inhibiting the aggregation reaction between bacteria or decomposing the aggregation of bacteria.

In the oral composition of the present invention, the content of the component (a) is 6 mass% or more, preferably 8 mass% or more, more preferably 10 mass% or more, even more preferably 12 mass% or more, and even more preferably 14 mass% or more, from the viewpoint of maintaining the biofilm formation-inhibiting effect and the biofilm-removing effect and sufficiently exhibiting the accelerating effect by the formation of the coating film of the component (B) and the component (C). In order to effectively avoid excessive increase in pain due to dentinal hypersensitivity due to osmotic pressure stimulation, the content of the component (a) in the oral composition of the present invention is 33 mass% or less, preferably 30 mass% or less, more preferably 25 mass% or less, further preferably 20 mass% or less, and further more preferably 18 mass% or less. In the oral composition of the present invention, the content of the component (a) is 6 to 33 mass%, preferably 8 to 30 mass%, more preferably 10 to 25 mass%, even more preferably 12 to 20 mass%, even more preferably 14 to 18 mass%.

The oral composition of the present invention contains sodium fluoride as the component (B). As a result, the biofilm formation inhibiting effect and the removal effect by the component (a) can be ensured, and after the oral composition of the present invention is applied to the oral cavity, fluoride ions are rapidly released in the process of exerting the film formation promoting effect by the component (a), and a fluoride film is efficiently formed on the surface of dentin together with the component (C) described later. Therefore, the coating effectively blocks dentinal tubules, and thus can effectively suppress the increase of pain caused by dentinal hypersensitivity due to osmotic pressure stimulation mainly caused by a high content of the component (a).

From the viewpoint of efficiently forming a fluoride coating, the content of the component (B) in the oral composition of the present invention is preferably 0.1% by mass or more, more preferably 0.2% by mass or more, further preferably 0.3% by mass or more, and further preferably 0.5% by mass or more. In the oral composition of the present invention, the content of the component (B) is preferably 2.5% by mass or less, more preferably 2.2% by mass or less, even more preferably 2% by mass or less, and even more preferably 1.8% by mass or less, from the viewpoint of ensuring the storage stability of the composition. In the oral composition of the present invention, the content of the component (B) is preferably 0.1 to 2.5% by mass, more preferably 0.2 to 2.2% by mass, even more preferably 0.3 to 2% by mass, and even more preferably 0.5 to 1.8% by mass.

The oral composition of the present invention contains calcium glycerophosphate as component (C). The component (C) can form a fluoride efficiently and form a film in cooperation with the component (B) by utilizing the effect of promoting the film formation of the component (a), and can contribute greatly to the occlusion of the dentinal tubules.

In the oral composition of the present invention, the content of the component (C) is preferably 0.1% by mass or more, more preferably 0.3% by mass or more, even more preferably 0.5% by mass or more, and even more preferably 1% by mass or more, from the viewpoint of efficiently and efficiently forming a fluoride coating together with the component (B) in the presence of the component (a). In the oral composition of the present invention, the content of the component (C) is preferably 5% by mass or less, more preferably 4.5% by mass or less, even more preferably 4% by mass or less, and even more preferably 3.5% by mass or less, from the viewpoint of ensuring the storage stability of the composition. In the oral composition of the present invention, the content of the component (C) is preferably 0.1 to 5% by mass, more preferably 0.3 to 4.5% by mass, even more preferably 0.5 to 4% by mass, and even more preferably 1 to 3.5% by mass.

From the viewpoint of promoting the formation of a film of fluoride, the mass ratio (Ca/F) of the amount of calcium atoms in the component (C) to the amount of fluorine atoms in the component (B) is preferably 0.35 or more, more preferably 0.38 or more, and still more preferably 0.42 or more. The mass ratio (Ca/F) of the amount of calcium atoms in the component (C) to the amount of fluorine atoms in the component (B) is preferably 0.55 or less, more preferably 0.52 or less, and still more preferably 0.5 or less. The mass ratio (Ca/F) of the amount of calcium atoms in the component (C) to the amount of fluorine atoms in the component (B) is preferably 0.35 to 0.55, more preferably 0.38 to 0.52, and still more preferably 0.42 to 0.5.

From the viewpoint of effectively avoiding excessive enhancement of pain caused by dentinal hypersensitivity due to osmotic pressure stimulation, the value of the mass ratio of the calcium atom-equivalent amount of the component (C) to the fluorine atom-equivalent amount of the component (B) (Ca/F)/(A, unit: mass%)^-1) Preferably 0.015 or more, more preferably 0.017 or more, and still more preferably 0.02 or more. In addition, from the viewpoint of maintaining the biofilm formation inhibiting effect and the biofilm removing effect and sufficiently exhibiting the effect of promoting the formation of a coating film by the component (B) and the component (C), the mass ratio of the calcium atom equivalent amount of the component (C) to the fluorine atom equivalent amount of the component (B) (Ca/F)/(a), unit: mass%^-1) Preferably 0.15 or less, more preferably 0.1 or less, and still more preferably 0.07 or less. And the value of the mass ratio of the amount of calcium atoms in the component (C) to the amount of fluorine atoms in the component (B) (Ca/F)/(A, unit: mass%)^-1) Preferably 0.015 to 0.15, more preferably 0.017 to 0.1, and still more preferably 0.020 to 0.07。

From the viewpoint of sufficiently utilizing the excellent fluoride coating formation promoting effect of the component (a), the mass ratio ((C)/(a)) of the content of the component (C) to the content of the component (a) is preferably 0.02 or more, more preferably 0.05 or more, further preferably 0.1 or more, and preferably 0.3 or less, more preferably 0.28 or less, further preferably 0.24 or less, further more preferably 0.18 or less. The mass ratio ((C)/(a)) of the content of the component (C) to the content of the component (a) is preferably 0.02 to 0.3, more preferably 0.05 to 0.28, even more preferably 0.1 to 0.24, even more preferably 0.1 to 0.18.

The oral composition of the present invention contains water as the component (D). By adjusting the water content, the enhancement of pain caused by dentinal hypersensitivity due to osmotic pressure stimulation mainly caused by the high content of the component (A) is effectively avoided. Further, the composition contains fluoride ions released from the component (B), and the component (a) is sufficiently distributed in the oral cavity, so that the formation of a fluoride coating by the component (B) and the component (C) is promoted, and thereby the dentinal tubules can be rapidly and efficiently blocked by the coating.

The content of the component (D) in the oral composition of the present invention is preferably 55 mass% or more, more preferably 60 mass% or more, even more preferably 65 mass% or more, even more preferably 68 mass% or more, and preferably 93 mass% or less, more preferably 91 mass% or less, even more preferably 89 mass% or less, even more preferably 88 mass% or less, even more preferably 87 mass% or less, and even more preferably 86.7 mass% or less, from the viewpoint of suppressing the osmotic pressure stimulation mainly caused by the high content of the component (a), from the viewpoint of efficiently forming a fluoride coating to improve the occlusion effect of the dentinal tubules by the component (B) and the component (C), and from the viewpoint of effectively exerting the biofilm formation suppressing effect or removing effect by the component (a). In the oral composition of the present invention, the content of the component (D) is preferably 55 to 93 mass%, more preferably 60 to 91 mass%, even more preferably 65 to 89 mass%, even more preferably 68 to 88 mass%, even more preferably 68 to 87 mass%, even more preferably 68 to 86.7 mass%.

From the viewpoint of ensuring an excellent fluoride film formation promoting effect by the component (a) and controlling the amount of the component (a) appropriately mainly because the component (a) is a high-content osmotic pressure stimulus, thereby improving the occlusion effect of the dentinal tubules by the fluoride film, the mass ratio ((a)/(D)) of the content of the component (a) to the content of the component (D) is 0.06 or more, preferably 0.08 or more, more preferably 0.09 or more, still more preferably 0.1 or more, and 0.3 or less, preferably 0.26 or less, more preferably 0.24 or less, still more preferably 0.22 or less. The mass ratio ((A)/(D)) of the content of the component (A) to the content of the component (D) is 0.06 to 0.3, preferably 0.08 to 0.26, more preferably 0.09 to 0.24, and still more preferably 0.1 to 0.22.

The oral composition of the present invention preferably contains an anionic surfactant in a limited amount from the viewpoint of efficiently and effectively forming a fluoride coating film by the component (B) and the component (C) in the presence of the component (a). Examples of the anionic surfactant include: sodium lauryl sulfate, sodium lauroyl methyl taurate, and the like. In the oral composition of the present invention, the content of the anionic surfactant is preferably less than 1% by mass, more preferably less than 0.6% by mass, even more preferably less than 0.4% by mass, even more preferably less than 0.2% by mass, even more preferably less than 0.08% by mass, or preferably the oral composition of the present invention does not substantially contain the anionic surfactant.

In the oral composition of the present invention, it is preferable to limit the total content of the fluorine compound and the polyvalent metal salt other than the component (B) from the viewpoint of effectively and efficiently forming a fluoride coating film in the presence of the component (a) by the component (B) and the component (C) to improve the occlusion effect of the dentinal tubules by the fluoride coating film. Specific examples of the fluorine compound other than the component (B) include the following fluorine compounds: fluorine ion supplying compounds such as potassium fluoride and ammonium fluoride, and fluorine-containing compounds such as sodium monofluorophosphate. Specific examples of the polyvalent metal salt include 1 or 2 or more salts selected from copper, iron, calcium, magnesium, aluminum, zinc, and tin. In the oral composition of the present invention, the total content of the fluorine compound and the polyvalent metal salt other than the component (B) is preferably less than 0.02% by mass, more preferably 0.015% by mass or less, and even more preferably 0.005% by mass or less, or the oral composition of the present invention preferably does not contain the fluorine compound and the polyvalent metal salt other than the component (B).

The oral composition of the present invention may contain no abrasive, or may contain an abrasive within a limit of the total content of the fluorine compound and the polyvalent metal salt other than the component (B). The polishing agent includes 1 or 2 or more selected from abrasive silica (having an oil absorption of 50 to 150mL/100g, obtained from the amount of the cooked linseed oil absorbed in accordance with JIS K5101-13-2 (established in 2004)), calcium hydrogen phosphate dihydrate and anhydride, calcium pyrophosphate, calcium carbonate, alumina, aluminum hydroxide, magnesium acetate, magnesium hydrogen phosphate, zeolite, and the like.

The oral composition of the present invention may contain, in addition to the above components, as appropriate within a range not interfering with the effects of the present invention: surfactants such as amphoteric surfactants including cationic surfactants and coconut oil fatty acid amidopropyl betaine, and nonionic surfactants including polyoxyethylene hydrogenated castor oil, sucrose fatty acid esters, and sorbitan fatty acid esters; polyhydric alcohols such as glycerin, propylene glycol, and polyethylene glycol; binders such as sodium alginate, sodium carboxymethylcellulose, carrageenan, xanthan gum, sodium polyacrylate, hydroxyethyl cellulose, hydroxypropyl cellulose, pectin, tragacanth, acacia, guar gum, and the like; a tackifying silica; sweetening agents such as saccharin sodium; a fragrance; a pigment; a medicinal effect component.

The pH of the oral composition of the present invention at 25 ℃ is preferably 5.0 or more, more preferably 6.0 or more, even more preferably 6.5 or more, and even more preferably 6.7 or more, from the viewpoint of efficiently promoting the formation of a fluoride coating film by the component (B) and the component (C) in the presence of the component (a). The oral composition of the present invention has a pH at 25 ℃ of preferably 10.0 or less, more preferably 9.6 or less, even more preferably 9.3 or less, and even more preferably 8.8 or less, from the viewpoint of avoiding discoloration of the composition.

The pH value of the oral composition of the present invention is a value measured at 25 ℃ using a pH electrode, and when the oral composition of the present invention is a liquid dentifrice composition, it means a value measured without diluting the composition, and when the oral composition of the present invention is a toothpaste composition, it means a value measured after being adjusted to a 10 mass% aqueous solution using purified water containing ion-exchanged water or distilled water.

The composition for oral cavity of the present invention can effectively and effectively prevent pain caused by dentinal hypersensitivity by a fluoride coating, and therefore, it can be widely used as a composition for oral cavity for dentinal hypersensitivity, that is, a dentinal hypersensitivity relieving agent or a prophylactic agent.

The method for producing the oral composition of the present invention is not particularly limited, and the above-mentioned components may be appropriately mixed by a conventional method.

With respect to the above embodiments, the present invention further discloses the following oral compositions.

[1] An oral composition comprising the following components (A), (B), (C) and (D):

(A) erythritol of 6 to 33 mass%,

(B) Sodium fluoride,

(C) Calcium glycerophosphate,

(D) The amount of water is controlled by the amount of water,

the mass ratio ((A)/(D)) of the content of the component (A) to the content of the component (D) is 0.06 to 0.2.

[2] The oral composition according to [1], wherein the content of the component (A) is preferably 8% by mass or more, more preferably 10% by mass or more, further preferably 12% by mass or more, further preferably 14% by mass or more, and preferably 30% by mass or less, more preferably 25% by mass or less, further preferably 20% by mass or less, further more preferably 18% by mass or less.

[3] The oral composition according to [1] or [2], wherein the content of the component (B) is preferably 0.1% by mass or more, more preferably 0.2% by mass or more, further preferably 0.3% by mass or more, further preferably 0.5% by mass or more, and preferably 2.5% by mass or less, more preferably 2.2% by mass or less, further preferably 2% by mass or less, further preferably 1.8% by mass or less.

[4] The oral composition according to any one of the above [1] to [3], wherein the content of the component (C) is preferably 0.1% by mass or more, more preferably 0.3% by mass or more, further preferably 0.5% by mass or more, further preferably 1% by mass or more, and preferably 5% by mass or less, more preferably 4.5% by mass or less, further preferably 4% by mass or less, further preferably 3.5% by mass or less.

[5] The oral composition according to any one of the above [1] to [4], wherein the content of the component (D) is preferably 55% by mass or more, more preferably 60% by mass or more, further preferably 65% by mass or more, further preferably 68% by mass or more, and preferably 93% by mass or less, more preferably 91% by mass or less, further preferably 89% by mass or less, further preferably 88% by mass or less, further preferably 87% by mass or less, further preferably 86.7% by mass or less.

[6] The oral composition according to any one of [1] to [5] above, wherein the mass ratio ((a)/(D)) of the content of the component (a) to the content of the component (D) is preferably 0.08 or more, more preferably 0.09 or more, further preferably 0.1 or more, and preferably 0.26 or less, more preferably 0.24 or less, further preferably 0.22 or less.

[7] The oral composition according to any one of the above [1] to [6], wherein the content of the anionic surfactant is preferably less than 1% by mass, more preferably less than 0.6% by mass, even more preferably less than 0.4% by mass, even more preferably less than 0.2% by mass, even more preferably less than 0.08% by mass, or substantially no anionic surfactant.

[8] The oral composition according to any one of the above [1] to [7], wherein the mass ratio (Ca/F) of the amount of calcium atoms converted in the component (C) to the amount of fluorine atoms converted in the component (B) is preferably 0.35 or more, more preferably 0.38 or more, even more preferably 0.42 or more, and preferably 0.55 or less, more preferably 0.52 or less, even more preferably 0.5 or less.

[9] The oral composition according to any one of [1] to [8], wherein the total content of the fluorine compound and the polyvalent metal salt other than the component (B) is preferably less than 0.02% by mass, more preferably 0.015% by mass or less, and further preferably 0.005% by mass or less, or fluoride and the polyvalent metal salt other than the component (B) are not contained.

[10] The oral composition according to any one of [1] to [9] above, wherein the mass ratio ((C)/(a)) of the content of the component (C) to the content of the component (a) is preferably 0.02 or more, more preferably 0.05 or more, further preferably 0.1 or more, and preferably 0.3 or less, more preferably 0.28 or less, further preferably 0.24 or less, further more preferably 0.18 or less.

[11]As described above [1]To [10]]The oral composition according to any one of the above, wherein the value of the ratio of the mass ratio of the amount of calcium atoms converted in the component (C) to the amount of fluorine atoms converted in the component (B) (Ca/F)/(A), unit: mass%^-1) Preferably 0.015 or more, more preferably 0.017 or more, further preferably 0.02 or more, and preferably 0.15 or less, more preferably 0.1 or less, further preferably 0.07 or less.

[12] The oral composition according to any one of the above [1] to [11], wherein the pH at 25 ℃ is preferably 5.0 or more, more preferably 6.0 or more, further preferably 6.5 or more, further preferably 6.7 or more, and preferably 10.0 or less, more preferably 9.6 or less, further preferably 9.3 or less, further preferably 8.8 or less.

[ examples ]

The present invention will be specifically described below based on examples. The contents of the respective components are expressed by mass% unless otherwise specified in the table.

Examples 1 to 12 and comparative examples 1 to 5

The liquid dentifrice compositions of examples 1 to 12 and comparative examples 1 to 5 shown in table 1 were prepared by mixing the respective components by a conventional method.

Then, using the obtained liquid dentifrice composition and the following dentin samples, the state of the mouth blocking of the dentinal tubules and the fluoride coating were observed by the following methods, and the sensory hypersensitivity and the inhibition rate of tartar formation were evaluated and measured.

Test 1: evaluation of the blocking of the opening of the dentinal tubule and the formation of fluoride coating

Preparation of dentin sample

The surface of about 1cm each of the sliced sections (about 500 μm in thickness) of dentin of bovine teeth was mirror-polished using a sandpaper having a particle size of 40 μm and a sandpaper having a particle size of 3 μm, and then subjected to ultrasonic treatment for 10 minutes. Then, the coating layer was completely removed by etching with a 1% citric acid aqueous solution for 20 seconds and ultrasonic treatment was performed again for 10 minutes to expose the opening of the dentinal tubule of the bovine tooth.

Observation with an Electron microscope

The obtained dentin sample was immersed in 10mL of each of the liquid dentifrice compositions of example 3 and comparative example 2 for 5 minutes, and then the sample was washed with distilled water for 10 seconds. After the washing, platinum deposition was performed on the surface of the sample that was sufficiently dried, and the opening of the dentinal tubules in the surface was observed at a magnification of 2000 times using an electron microscope (VE-7800, manufactured by KEYENCE corporation, acceleration voltage 2kV), and the state of the opening blocking of the dentinal tubules and the state of formation of the fluoride coating were confirmed.

The results are shown in FIGS. 1 to 2.

From the results of fig. 1 to 2, it was confirmed that the opening of the dentinal tubules in the surface of the sample was sufficiently blocked by being well covered with the fluoride coating in example 3, whereas it was confirmed that the adherent was observed on the surface of the dentin in comparative example 2, but only the portion covering the opening of the dentinal tubules and the portion where the dentin was exposed were dispersed.

Test 2: sensory hypersensitivity assessment

The subjects who had felt stinging pain every day during the last 1 month or the subjects who had felt stinging pain 2 to 3 times a week were used as the sensory examiners, and 3 sensory examiners were allowed to hold each liquid dentifrice composition for 30 seconds and rinse their mouth, and thereafter, the subjects were kept in cold water and evaluated for pain due to dentinal hypersensitivity according to the following criteria.

4: no pricking pain at all

3: hardly feels stabbing pain

2: feel a bit stabbing pain

1: feeling of stabbing pain

The average of the evaluation results of 3 functional inspectors is shown in table 1.

Test 3: determination of inhibition of tartar formation

1) Treatment of HAp substrates with liquid dentifrice compositions

One surface of a HAp substrate (1 cm square, manufactured by COSMO BIO corporation) was mirror-polished using 40 μm, 12 μm, and 3 μm polishing paper, and then immersed in 1N HCl for 1 minute to perform acid decalcification. The treated HAp plate was washed with ion-exchanged water, dried, put into a 24-well plate, 1mL of each of the liquid dentifrice compositions obtained in examples and comparative examples was added thereto, and shaken for 5 minutes. The shaking was carried out at room temperature (25 ℃ C.) and 500rpm using a shaker (BioShake iQ (manufactured by WAKENBTECH)). Thereafter, each liquid dentifrice composition was aspirated, 1mL of ion-exchanged water was added thereto, and after 5 minutes of shaking, water was aspirated to prepare a treated substrate.

2) Stimulated saliva Collection

Healthy males of 20 to 30 years old were allowed to chew gum particles contained in a Dentobuff Strip (OralCare Inc.), and saliva accumulated in the mouth at each time was spitted into a Falcon tube, thereby collecting the saliva in the Falcon tube. Furthermore, since the bacteria in saliva are different among individuals, the tartar formation inhibition rate was measured for all of the examples and comparative examples based on saliva of 1 healthy male.

3) Making of model tartar

Next, the saliva collected in the Falcon tube of 2) was centrifuged at 3000rpm/rt/10 min. A sucralose solution was prepared by adding sucrose in an amount of 5 mass% to the separated supernatant saliva, and then stirred by a stirrer (Voltex, manufactured by NIPPON Genetics) to prepare a dental calculus model test solution.

4) Evaluation of inhibition Rate of Tartar formation

Adding 1mL of the model tartar test solution prepared in 3) to the HAp substrate treated in 1) per well, and then adding CO thereto₂The bags were stored in a plastic box and incubated at 37 ℃ for 24 hours under anaerobic conditions.

5) CV staining of tartar

The model tartar test solution in the plate was aspirated by a vacuum pump, and 1mL of ion-exchanged water was added thereto and the plate was shaken for 5 minutes. Next, water was removed by a pump, and 750 μ L of a 0.1 mass% Crystal Violet (CV) solution was added thereto, followed by shaking for 15 minutes.

Further, the CV solution was aspirated by a pump, 1mL of ion-exchanged water was added thereto, and the mixture was shaken for 5 minutes, and the above operation was repeated 2 times. Subsequently, water was removed by a pump, 500. mu.L of ethanol was added, and after pipetting, the extract was diluted 10-fold with ion-exchanged water.

6) Evaluation of inhibition Rate of Tartar formation

The obtained ion-exchanged water 10-fold diluted solution was measured for absorbance OD by a microplate detector (Sunrise Rainbow Thermo, a wavelength-variable light-absorbing microplate reader manufactured by TECAN corporation)_595nm。

Further, the absorbance OD in the case of forming model tartar on an HAp plate after acid decalcification treatment without using the liquid dentifrice composition obtained as described above was used_595nm(initial value) As a reference, the tartar formation inhibition (%) was calculated according to the following formula.

Further, the higher the value of the tartar formation inhibition ratio obtained, the higher the tartar formation inhibition effect.

Tartar formation inhibition (%) of 100- { OD of substrate treated with the liquid dentifrice composition obtained as described above_595nmOD of untreated substrate_595nm}×100

The results are shown in Table 1.