TWI842814B - Oral composition - Google Patents

Abstract

The present invention relates to an oral composition that effectively inhibits the increase in pain caused by dentine sensory hypersensitivity by a high content of erythritol. That is, the present invention is an oral composition that contains the following components (A), (B), (C) and (D): (A) erythritol 6 mass% to 33 mass%, (B) sodium fluoride, (C) calcium glycerophosphate, (D) water, and the mass ratio of the content of component (A) to the content of component (D) ((A)/(D)) is 0.06 to 0.2.

Description

Oral composition

The present invention relates to an oral composition.

To date, the most effective way to prevent oral diseases such as cavities, periodontal disease and halitosis is to inhibit the formation of oral biofilms and remove the biofilms that have already formed. The industry is developing oral compositions using a variety of ingredients such as abrasives, foaming agents, or disinfectants.

Among such ingredients, for example, Patent Document 1 also discloses that erythritol is an effective ingredient in inhibiting or dissolving the aggregation reaction of bacteria in the oral cavity. It is known that it not only has an excellent effect in inhibiting the formation of biofilms, but also has an excellent effect in removing biofilms formed between teeth or in periodontal pockets. In addition, in the tooth cleaning composition disclosed in Patent Document 2, the content of erythritol is set high, thereby further improving the effect of removing biofilms in the oral cavity.

(Patent document 1) Japanese Patent Publication No. 2005-29484 (Patent document 2) Japanese Patent Publication No. 2012-36172

The present invention provides an oral composition containing the following components (A), (B), (C) and (D): (A) erythritol 6 mass % to 33 mass %, (B) sodium fluoride, (C) calcium glycerophosphate, (D) water, and the mass ratio of the content of component (A) to the content of component (D) ((A)/(D)) is 0.06 to 0.2.

The inventors of the present invention have found that if erythritol, which has excellent inhibitory and removal effects on oral biofilm formation, is used at high levels as in the above patent literature, the pain caused by dentine sensory hypersensitivity is enhanced mainly due to the osmotic pressure stimulation of erythritol dissolved in water. Thus, the industry strongly desires to achieve an oral composition that contains high levels of erythritol, which has excellent inhibitory and removal effects on oral biofilm formation and can effectively prevent pain caused by dentine sensory hypersensitivity.

Therefore, the inventors have conducted various studies and found that by setting the content of erythritol to a high level and setting the mass ratio of erythritol to water to a specific level, and using sodium fluoride and calcium glycerophosphate together, an oral composition can be obtained, which can effectively reduce the osmotic pressure stimulation mainly caused by erythritol, and efficiently form a fluoride film such as calcium fluoride that effectively blocks the opening of the dentinal tubules in the surface of the exposed dentin, thereby effectively preventing the increase of pain caused by dentinal sensory hypersensitivity.

That is, the present invention relates to an oral composition which can effectively inhibit the pain enhancement caused by dentine sensory hypersensitivity by using a high content of erythritol.

According to the oral composition of the present invention, although the content of erythritol is high, the osmotic pressure stimulation mainly caused by erythritol can be reduced, and the opening of the dentinal tubules in the surface of the exposed dentine can be efficiently and effectively blocked by the fluoride coating, so that the excellent effect of inhibiting the pain caused by dentine sensory hypersensitivity can be fully exerted. Therefore, the excellent effect of inhibiting the formation and removing the biofilm in the oral cavity can also be fully enjoyed by the high content of erythritol.

The present invention is described in detail below. Furthermore, in the present invention, "dentinal tubules" are also referred to as "dentinal tubules". Moreover, "blocking the dental tubules" means physically blocking the dental tubules, which means not only covering the openings or the periphery of the openings of the dental tubules on the surface of the dentin, but also filling the tubules near the surface of the dental tubules to cover (plug) them. Furthermore, in the present invention, "fluoride" mainly refers to fluorine-containing inorganic compounds such as calcium fluoride formed by component (B) and component (C), and the fluoride coating is also referred to as "fluoride coating".

The oral composition of the present invention contains erythritol as component (A) in an amount of not less than 6 mass % and not more than 33 mass %. Thereby, the formation of the fluoride film by components (B) and (C) described later is promoted, and the film can effectively physically block the dentine tubules, thereby exerting the effect of inhibiting the pain caused by dentine sensory hypersensitivity. In addition, the aggregation reaction between bacteria is inhibited, or the aggregation between bacteria is dissociated, and the original effect of erythritol, that is, the inhibition effect or removal effect of biofilm formation can also be exerted.

From the viewpoint of maintaining the biofilm formation inhibition effect and removal effect, and fully exerting the film formation promotion effect of component (B) and component (C), in the oral composition of the present invention, the content of component (A) is 6% by mass or more, 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. In addition, from the viewpoint of effectively avoiding excessive enhancement of pain caused by dentine sensory hypersensitivity due to osmotic pressure stimulation, in the oral composition of the present invention, the content of component (A) is 33% by mass or less, preferably 30% by mass or less, more preferably 25% by mass or less, further preferably 20% by mass or less, further preferably 18% by mass or less. Furthermore, in the oral composition of the present invention, the content of component (A) is 6 mass % to 33 mass %, preferably 8 to 30 mass %, more preferably 10 to 25 mass %, further preferably 12 to 20 mass %, further preferably 14 to 18 mass %.

The oral composition of the present invention contains sodium fluoride as component (B). Thereby, the biofilm formation inhibition effect and removal effect of the above-mentioned component (A) can be ensured, and after the oral composition of the present invention is applied to the oral cavity, in the process of exerting the film formation promotion effect of the above-mentioned component (A), fluoride ions are quickly released, and together with the component (C) described later, a fluoride film is efficiently formed on the surface of the dentin. Therefore, the film effectively blocks the dental tubules, and the pain enhancement caused by dentin sensory hypersensitivity, which is mainly caused by the osmotic pressure stimulation of the high content of component (A), can be effectively suppressed.

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

The oral composition of the present invention contains calcium glycerophosphate as component (C). The component (C) can efficiently form fluoride and form a film with the component (B) under the effect of promoting the film formation of the component (A), thereby greatly contributing to the blockage of the dentine tubules.

From the viewpoint of effectively and efficiently forming a fluoride film together with component (B) in the presence of component (A), the content of component (C) in the oral composition of the present invention 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. Furthermore, from the viewpoint of ensuring the storage stability of the composition, the content of component (C) in the oral composition of the present invention is 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. Furthermore, in the oral composition of the present invention, the content of component (C) is preferably 0.1 mass % to 5 mass %, more preferably 0.3 to 4.5 mass %, further preferably 0.5 to 4 mass %, further preferably 1 to 3.5 mass %.

From the viewpoint of promoting the coating of fluoride, the mass ratio (Ca/F) of the amount of calcium atom converted into component (C) to the amount of fluorine atom converted into component (B) is preferably 0.35 or more, more preferably 0.38 or more, and further preferably 0.42 or more. In addition, the mass ratio (Ca/F) of the amount of calcium atom converted into component (C) to the amount of fluorine atom converted into component (B) is preferably 0.55 or less, more preferably 0.52 or less, and further preferably 0.5 or less. Furthermore, the mass ratio (Ca/F) of the amount of calcium atom converted into component (C) to the amount of fluorine atom converted into component (B) is preferably 0.35 or more and 0.55 or less, more preferably 0.38 to 0.52, and further preferably 0.42 to 0.5.

From the viewpoint of effectively avoiding excessive enhancement of pain caused by ivory sensory hypersensitivity due to osmotic pressure stimulation, the mass ratio (Ca/F) of the calcium atom equivalent amount of component (C) to the fluorine atom equivalent amount of component (B) relative to the content of component (A) ((Ca/F)/(A), unit: mass % ^-1 ) is preferably 0.015 or more, more preferably 0.017 or more, and further preferably 0.02 or more. Furthermore, from the viewpoint of maintaining the biofilm formation inhibitory effect and removal effect and fully exerting the film formation promoting effect of components (B) and (C), the value of the ratio of the mass ratio (Ca/F) of the calcium atom equivalent amount of component (C) to the fluorine atom equivalent amount of component (B) relative to the content of component (A) ((Ca/F)/(A), unit: mass % ^-1 ) is preferably 0.15 or less, more preferably 0.1 or less, and further preferably 0.07 or less. Furthermore, the mass ratio (Ca/F) of the calcium atom equivalent amount of component (C) to the fluorine atom equivalent amount of component (B) relative to the content of component (A) ((Ca/F)/(A), unit: mass % ^-1 ) is preferably 0.015 to 0.15, more preferably 0.017 to 0.1, and further preferably 0.020 to 0.07.

From the viewpoint of fully utilizing the excellent fluoride film formation promoting effect of component (A), the mass ratio of the content of component (C) to the content of component (A) ((C)/(A)) is preferably 0.02 or more, more preferably 0.05 or more, further preferably 0.1 or more, and is preferably 0.3 or less, more preferably 0.28 or less, further preferably 0.24 or less, further preferably 0.18 or less. Furthermore, the mass ratio of the content of component (C) to the content of component (A) ((C)/(A)) is preferably 0.02 or more and 0.3 or less, more preferably 0.05 to 0.28, further preferably 0.1 to 0.24, further preferably 0.1 to 0.18.

The oral composition of the present invention contains water as component (D). By adjusting the content of water, the pain caused by dentine sensory hypersensitivity, which is mainly caused by the osmotic pressure stimulation of the high content of component (A), is effectively avoided. In addition, fluoride ions released from component (B) exist in the composition, and component (A) is fully distributed in the oral cavity, promoting the formation of a fluoride film by components (B) and (C), so that the dentine tubules can be quickly and efficiently blocked by the film.

From the viewpoint that the main reason for the inhibition is the osmotic pressure stimulation caused by the high content of component (A), the blocking effect of the dentate tubules is enhanced by the efficient formation of a fluoride film by components (B) and (C), and the biofilm formation inhibition effect or removal effect is effectively exerted by component (A), in the oral composition of the present invention, the content of 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, further 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. Furthermore, in the oral composition of the present invention, the content of component (D) is preferably 55 mass % to 93 mass %, more preferably 60 to 91 mass %, further preferably 65 to 89 mass %, further preferably 68 to 88 mass %, further preferably 68 to 87 mass %, further preferably 68 to 86.7 mass %.

From the viewpoint of ensuring the excellent fluoride film formation promoting effect of component (A) and appropriately controlling the osmotic pressure stimulation mainly due to the high content of component (A) to enhance the blocking effect of dentate tubules by fluoride film, the mass ratio of the content of component (A) to the content of component (D) ((A)/(D)) is 0.06 or more, preferably 0.08 or more, more preferably 0.09 or more, further preferably 0.1 or more, and is 0.3 or less, preferably 0.26 or less, more preferably 0.24 or less, further preferably 0.22 or less. Furthermore, the mass ratio of the content of component (A) to the content of component (D) ((A)/(D)) is 0.06 to 0.3, preferably 0.08 to 0.26, more preferably 0.09 to 0.24, and further preferably 0.1 to 0.22.

From the perspective of effectively and efficiently forming a fluoride film by component (B) and component (C) in the presence of component (A), the oral composition of the present invention preferably contains limited anionic surfactants. Examples of the anionic surfactants include sodium lauryl sulfate and sodium lauryl methyl taurate. 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, further preferably less than 0.4% by mass, further preferably less than 0.2% by mass, further preferably less than 0.08% by mass, or the oral composition of the present invention preferably does not substantially contain anionic surfactants.

From the viewpoint of effectively and efficiently forming a fluoride film by components (B) and (C) in the presence of component (A) to enhance the blocking effect of the fibrous tubules by the fluoride film, the oral composition of the present invention preferably limits the total content of fluoride compounds and polyvalent metal salts other than component (B). Specifically, the following fluoride compounds can be listed as fluoride compounds other than component (B): fluoride ion supply compounds such as potassium fluoride and ammonium fluoride, and fluorine-containing compounds such as sodium monofluorophosphate. In addition, as polyvalent metal salts, specifically, one or more salts selected from copper, iron, calcium, magnesium, aluminum, zinc, and tin can be listed. 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 mass %, more preferably less than 0.015 mass %, further preferably less than 0.005 mass %, or the oral composition of the present invention preferably does not contain fluorine compounds and polyvalent metal salts other than the component (B).

The oral composition of the present invention may not contain an abrasive, or may contain an abrasive within the limit of the total content of the fluorine compound and the polyvalent metal salt other than the component (B). The abrasive may be one or more selected from abrasives such as abrasive silica (oil absorption 50 to 150 mL/100 g, obtained from the amount of cooked linseed oil absorbed according to JIS K5101-13-2 (established in 2004), secondary calcium phosphate-dihydrate and anhydrous, calcium pyrophosphate, calcium carbonate, aluminum oxide, aluminum hydroxide, magnesium acetate, secondary magnesium phosphate, magnesium acetate, tertiary magnesium phosphate, zeolite, and the like.

In addition to the above-mentioned ingredients, the oral composition of the present invention may appropriately contain the following surfactants within the scope that does not hinder the effect of the present invention: cationic surfactants or amphoteric surfactants such as coconut oil fatty amide propyl betaine, polyoxyethylene hydrogenated castor oil or sucrose fatty acid esters, sorbitan fatty acid esters and other non-ionic surfactants; glycerol, propylene glycol, polyethylene glycol and other polyols; sodium alginate, sodium carboxymethyl cellulose, carrageenan, sesame gum, sodium polyacrylate, hydroxyethyl cellulose, hydroxypropyl cellulose, pectin, tragacanth gum, gum arabic, and guar gum; thickening silicon dioxide; sweeteners such as saccharin sodium; flavorings; pigments; and medicinal ingredients.

From the perspective of efficiently promoting the formation of the fluoride film by components (B) and (C) in the presence of component (A), the pH value of the oral composition of the present invention at 25°C is preferably 5.0 or more, more preferably 6.0 or more, further preferably 6.5 or more, further preferably 6.7 or more. In addition, from the perspective of avoiding discoloration of the composition, the pH value of the oral composition of the present invention at 25°C is preferably 10.0 or less, more preferably 9.6 or less, further preferably 9.3 or less, further preferably 8.8 or less. Furthermore, the pH value of the oral composition of the present invention is a value measured at 25° C. using a pH electrode. When the oral composition of the present invention is a liquid toothpaste composition, it means a value measured without diluting the composition. When the oral composition of the present invention is a toothpaste composition, it means a value measured after adjusting the aqueous solution to a concentration of 10 mass % using purified water containing ion-exchange water or distilled water.

Since the oral composition of the present invention can effectively and efficiently prevent the pain caused by dentine sensory hypersensitivity through fluoride coating, it can also be widely used as an oral composition for dentine sensory hypersensitivity, that is, a dentine sensory hypersensitivity alleviator or preventive agent.

The method for preparing the oral composition of the present invention is not particularly limited, and the above components can be appropriately mixed using a conventional method.

In relation to the above-mentioned embodiment, the present invention further discloses the following oral composition. [1] An oral composition comprising the following components (A), (B), (C) and (D): (A) erythritol in an amount of 6% to 33% by mass, (B) sodium fluoride, (C) calcium glycerophosphate, (D) water, and the mass ratio of the content of component (A) to the content of component (D) ((A)/(D)) is 0.06 to 0.2. [2] The oral composition of [1], wherein the content of 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 preferably 18% by mass or less. [3] The oral composition of [1] or [2], wherein the content of 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 [1] to [3] above, wherein the content of 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, further 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 [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 is 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 as described in any one of [1] to [5] above, wherein the mass ratio of the content of component (A) to the content of component (D) ((A)/(D)) is preferably 0.08 or more, more preferably 0.09 or more, and further preferably 0.1 or more, and is preferably 0.26 or less, more preferably 0.24 or less, and further preferably 0.22 or less. [7] The oral composition as described in any one of [1] to [6] above, wherein the content of the anionic surfactant is preferably less than 1% by mass, more preferably less than 0.6% by mass, further preferably less than 0.4% by mass, further preferably less than 0.2% by mass, further preferably less than 0.08% by mass, or the composition does not substantially contain anionic surfactant. [8] The oral composition of any one of [1] to [7] above, wherein the mass ratio (Ca/F) of the amount of calcium atom equivalent in component (C) to the amount of fluorine atom equivalent in component (B) is preferably 0.35 or more, more preferably 0.38 or more, and further preferably 0.42 or more, and is preferably 0.55 or less, more preferably 0.52 or less, and further preferably 0.5 or less. [9] The oral composition of any one of [1] to [8] above, wherein the total content of fluoride compounds and polyvalent metal salts other than component (B) is preferably less than 0.02 mass%, more preferably less than 0.015 mass%, and further preferably less than 0.005 mass%, or the composition does not contain fluoride compounds and polyvalent metal salts other than component (B). [10] The oral composition according to any one of [1] to [9], wherein the mass ratio of the content of the component (C) to the content of the component (A) ((C)/(A)) is preferably 0.02 or more, more preferably 0.05 or more, further preferably 0.1 or more, and is preferably 0.3 or less, more preferably 0.28 or less, further preferably 0.24 or less, further preferably 0.18 or less. [11] The oral composition according to any one of [1] to [10], wherein the mass ratio (Ca/F) of the amount of calcium atom equivalent of component (C) to the amount of fluorine atom equivalent of component (B) relative to the content of component (A) ((Ca/F)/(A), unit: mass % ^-1 ) is preferably 0.015 or more, more preferably 0.017 or more, further preferably 0.02 or more, and is 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 [1] to [11], wherein the pH value at 25°C is preferably 5.0 or higher, more preferably 6.0 or higher, further preferably 6.5 or higher, further preferably 6.7 or higher, and is preferably 10.0 or lower, more preferably 9.6 or lower, further preferably 9.3 or lower, further preferably 8.8 or lower. [Examples]

Hereinafter, the present invention will be specifically described based on the examples. In addition, unless otherwise indicated in the table, the content of each component is expressed in mass %.

[Examples 1 to 12, Comparative Examples 1 to 5] The liquid toothpaste compositions of Examples 1 to 12 and Comparative Examples 1 to 5 shown in Table 1 were prepared by mixing the components using a conventional method. Then, the liquid toothpaste compositions obtained were used with the following dentin samples to observe the blocking state of the opening of the dental tubules and the fluoride film, and the sensory hypersensitivity evaluation and the determination of the inhibition rate of plaque formation were performed using the following method.

Test 1: Evaluation of the blocking of the opening of the dentin tubules and the formation of the fluoride film 《Preparation of dentin samples》 The surfaces of approximately 1 cm sections of bovine dentin (thickness approximately 500 μm) were mirror-polished using sandpaper with a grain size of 40 μm and sandpaper with a grain size of 3 μm, and then subjected to ultrasonic treatment for 10 minutes. Subsequently, etching was performed for 20 seconds using a 1% citric acid aqueous solution, and ultrasonic treatment was performed again for 10 minutes to completely remove the smear layer and expose the opening of the dentin tubules of the bovine dentin.

《Electron Microscope Observation》 The obtained dentin sample was immersed in 10 mL of each liquid tooth cleaning composition of Example 3 and Comparative Example 2 for 5 minutes, and then the sample was washed with distilled water for 10 seconds. After washing, the surface of the fully dried sample was platinum evaporated, and the opening of the dental tubules on the surface was observed at a magnification of 2000 times using an electron microscope (VE-7800, manufactured by KEYENCE, accelerating voltage 2 kV) to confirm the blocking state of the opening of the dental tubules and the formation state of the fluoride film. The results are shown in Figures 1 and 2.

According to the results of Figures 1 and 2, in Example 3, it was confirmed that the openings of the dental tubules on the surface of the sample were well covered by the fluoride film and were fully blocked. In contrast, in Comparative Example 2, it was confirmed that although attachments were confirmed on the surface of the dentin, only the portions covering the openings of the dental tubules and the portions where the dentin was exposed were scattered.

Test 2: Sensory evaluation of sensory allergy Three sensory examiners were asked to hold each liquid tooth cleaning composition in their mouth for 30 seconds and rinse their mouths. They were then asked to hold cold water in their mouths and evaluate the pain caused by sensory allergy to the dentine according to the following criteria. 4: No tingling at all 3: Almost no tingling 2: Slight tingling 1: Tingling The average of the evaluation results of the three sensory examiners is shown in Table 1.

Experiment 3: Determination of plaque formation inhibition rate 1) Treatment of HAp substrate with various liquid toothpaste compositions The HAp (hydroxyapatite) substrate (manufactured by COSMO BIO, 1 cm square) was mirror-polished on one side using 40 μm, 12 μm, and 3 μm abrasive papers, and then immersed in 1 N HCl for 1 minute for acid decalcification. The treated HAp plate was washed with ion-exchange water, dried, placed in a 24-well plate, and 1 mL of each liquid toothpaste composition obtained in the example and comparative example was added, and vibrated for 5 minutes. The vibration was performed using a vibrator (BioShake iQ (manufactured by WAKENBTECH)) at room temperature (25°C) and 500 rpm. Afterwards, each liquid tooth cleaning composition was sucked off, 1 mL of ion exchange water was added, and after shaking for 5 minutes, the water was sucked off to prepare a treated substrate. 2) Stimulation of saliva collection Healthy males aged 20 to 30 were selected as subjects. They were asked to chew the gum particles contained in Dentobuff Strip (manufactured by OralCare Inc.) and spit out the saliva accumulated in the mouth into a Falcon tube each time, thereby collecting the saliva in the Falcon tube. In addition, since the bacteria in saliva vary from person to person, the plaque formation inhibition rate was measured for all examples and comparative examples based on the saliva of one healthy male.

3) Preparation of model plaque Next, the saliva collected in the Falcon tube in 2) was centrifuged at 3000 rpm/rt/10 min. After adding 5% sucrose by mass to the supernatant saliva obtained by separation to prepare a sucralose solution, it was stirred using a stirrer (Voltex, manufactured by NIPPON Genetics) to prepare a plaque model test solution. 4) Evaluation of plaque formation inhibition rate After adding 1 mL of the model plaque test solution prepared in 3) to each well of the HAp substrate treated in 1), it was stored in a plastic box together with a CO ₂ bag and cultured at 37°C under anaerobic conditions for 24 hours.

5) CV staining of dental plaque Use a pressure reducing pump to remove the model dental plaque test solution in the plate, add 1 mL of ion exchange water, and shake for 5 minutes. Next, use a pump to remove the water, add 750 μL of 0.1 mass% crystal violet (CV) solution, and shake for 15 minutes. Furthermore, use a pump to remove the CV solution, add 1 mL of ion exchange water, and shake for 5 minutes. Repeat the above operation twice. Next, use a pump to remove the water, add 500 μL of ethanol, and after pipetting, use ion exchange water to dilute the extract 10 times. 6) Evaluation of plaque formation inhibition rate The absorbance OD _{595 nm} of the obtained 10-fold dilution of ion exchange water was measured using a microplate reader (Sunrise Rainbow Thermo, a wavelength-variable absorbance microplate reader manufactured by TECAN). In addition, the absorbance OD _{595 nm} (initial value) of the case where a model plaque was prepared on an acid-decalcified HAp plate without using the above-obtained liquid toothpaste composition was used as a reference, and the plaque formation inhibition rate (%) was calculated according to the following formula. Furthermore, the larger the value of the obtained plaque formation inhibition rate, the higher the plaque formation inhibition effect. Plaque formation inhibition rate (%) = 100 - {OD _{595 nm} of the substrate treated with the liquid toothpaste composition obtained above / OD _{595 nm} of the untreated substrate} × 100 The results are shown in Table 1.

[Table 1] Embodiment 1 Embodiment 2 Embodiment 3 Embodiment 4 Embodiment 5 Embodiment 6 Embodiment 7 Embodiment 8 Embodiment 10 Embodiment 11 Embodiment 12 Comparison Example 1 Comparison Example 2 Comparison Example 3 Comparison Example 4 Comparison Example 5 (A) Erythritol 10 10 10 8 16 10 10 10 10 6 10 40 2 30 0 10 Xylitol 0 0 0 0 0 0 0 0 0 0 0 0 0 0 10 0 Propylene glycol 0 0 0 8 0 0 0 0 0 0 0 0 0 0 0 0 (B) Sodium fluoride 0.21 0.32 1.05 1.05 1.05 1.05 1.05 1.05 0.11 0.42 1.05 1.05 0.21 1.05 0.21 1.05 Sodium monofluorophosphate 0 0 0 0 0 0 0 0.01 0 0 0 0 0 0 0 0 (C) Calcium glycerophosphate 0.40 0.61 2.00 2.00 2.00 2.37 2.00 2.00 0.22 0.80 2.00 2.00 0.40 2.00 0.40 0 Calcium lactate 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2.00 Sodium Lauryl Sulfate 0 0 0 0 0 0 0.10 0 0 0 0 0 0 0 0 0 Apple acid 0 0 0 0 0 0 0 0 0 0 0.17 (D) Purified water 89.39 89.07 86.95 80.95 80.95 86.59 86.85 86.94 89.67 92.78 86.95 56.95 97.39 66.95 89.39 86.95 Total 100.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00 pH 9.4 9.4 9.6 9.2 8.6 9.9 9.0 8.9 8.6 8.6 6.5 9.0 9.1 9.0 8.5 7.4 (A)/(D) 0.11 0.11 0.12 0.10 0.20 0.12 0.12 0.12 0.11 0.06 0.12 0.70 0.02 0.45 - 0.12 Ca/F 0.38 0.38 0.38 0.38 0.38 0.45 0.38 0.38 0.40 0.38 0.38 0.38 0.38 0.38 0.38 - (Ca/F)/(A) 0.04 0.04 0.04 0.05 0.02 0.05 0.04 0.04 0.04 0.06 0.04 0.01 0.19 0.01 - - Sensory allergy assessment 3.3 3.7 4 4 4 4 3 3 4 3.3 4 1 4 1.7 2.3 2 Tartar formation inhibition rate [%] 42 42 45 45 47 46 37 38 40 35 34 46 31 43 twenty two 17

FIG1 is an electron microscope photograph of the surface of dentin when the oral composition of Example 3 is used. FIG2 is an electron microscope photograph of the surface of dentin when the oral composition of Comparative Example 2 is used.

Claims (8)

An oral composition comprising the following components (A), (B), (C) and (D): (A) erythritol at 6% to 33% by mass, (B) sodium fluoride, (C) calcium glycerophosphate at 0.22% to 3.5% by mass, (D) water, and the mass ratio of the content of component (A) to the content of component (D) ((A)/(D)) is 0.06 to 0.2. For example, in the oral composition of claim 1, the content of the anionic surfactant is less than 1% by mass. For example, in the oral composition of claim 1 or 2, the content of component (D) is 55% by mass or more and 93% by mass or less. For example, in the oral composition of claim 1 or 2, the mass ratio (Ca/F) of the calcium atom conversion amount of component (C) to the fluorine atom conversion amount of component (B) is 0.35 or more and 0.55 or less. For the oral composition of claim 1 or 2, the total content of fluorine compounds and polyvalent metal salts other than component (B) does not reach 0.02% by mass. For example, the oral composition of claim 1 or 2, wherein the pH value at 25°C is 5.0 or more and 10.0 or less. For example, in the oral composition of claim 1 or 2, the content of component (B) is greater than 0.1% by mass and less than 2.5% by mass. For example, the oral composition of claim 1 or 2 is used for dentine sensory allergy.