JP5206938B2 - Oral composition - Google Patents

Description

  The present invention drastically improves the deposition of minerals containing fluorine compounds in dentinal tubules, the dentinal tubules are constricted and sealed, and have excellent relief and prevention effects on dentinal hypersensitivity and have a good feeling of use. Relates to the composition.

  Dentin hypersensitivity is a pain sensation that is felt transiently when an external stimulus (relatively strong sweetness, acidity, heat, low temperature, pressure) is applied to the root surface of the dentin. Exogenous stimuli are transmitted to the pulpal nerve through the innumerable dentinal tubules present in the dentin, and cause dentin hypersensitivity. In order to develop hypersensitivity of the dentine, it is premised that the dentin at the root portion is exposed by gingival retraction, and the dentinal tubules existing on the surface of the exposed dentin are in a wide open state. Relief / prevention of dentinal hypersensitivity can be achieved by narrowing or blocking the dentinal tubule or its opening.

  When suffering from hypersensitivity of dentin, sufficient brushing is hindered to avoid the pain sensation, resulting in insufficient plaque removal, resulting in various troubles (caries, periodontal disease, calculus deposition, bad breath, etc.) cause. In addition, the intake of hot and cold foods is restricted, and it has a considerable adverse effect on eating habits. Therefore, improving and preventing dentin hypersensitivity in daily oral care is important for maintaining oral health.

  Various techniques have been implemented or proposed as techniques for alleviating or preventing dentin hypersensitivity. For example, in a dental clinic, a treatment for sealing dentinal tubules with an adhesive resin or the like is performed. On the other hand, among dentifrices used in the home, dentifrices containing an active ingredient that alleviates or prevents dentin hypersensitivity are commercially available.

  In general, there are two approaches to techniques for alleviating or preventing dentine hypersensitivity. The first approach is a technique for constricting and sealing dentinal tubules. For example, a technique in which aluminum lactate or the like is blended and a fluorine compound is blended (see Patent Documents 1 to 3), stannous fluoride is blended. Techniques (see Patent Documents 3 and 4), techniques in which strontium chloride is blended (see Patent Documents 5 and 6), techniques in which an oxalic acid compound is blended (see Patent Documents 7 and 8), and the like have been proposed. The second approach is a technique for relieving and preventing dentin hypersensitivity by blunting the nerves present in the dental pulp. For example, a technique containing potassium nitrate (see Patent Documents 9 and 10), potassium citrate was added. Techniques (see Patent Documents 11 and 12) are known. Potassium ions have the effect of blunting the pulpal nerve, and the ions reach the pulp and relieve the sensitivity to dentin.

  In the technology for constricting and sealing dentinal tubules, in the technology related to aluminum lactate, in the technology related to fluorine compounds such as sodium fluoride and sodium monofluorophosphate, ivory The effect of alleviating quality perception is insufficient, and problems such as improvement of deposition of fluorine compounds on dentin remain. In the technology related to stannous fluoride, a certain relaxation effect is recognized, but further improvement of the feeling of use such as astringency of mucous membrane by tin ions and stannous fluoride forming an insoluble precipitate in the formulation. The medicinal effect is easy to deactivate, the problem of stabilizing this, and the technology related to strontium chloride, if high concentration of strontium chloride (10% by mass) is not blended, sufficient medicinal effect can not be obtained, further feeling of use In the problem of improvement and improvement of formulation stabilization technology and technology related to oxalic acid compounds, calcium oxalate is deposited on the tooth surface other than the affected area after use, and a rough feeling is seen on the tooth surface. It is left.

  On the other hand, in the technology to relieve and prevent dentine hypersensitivity by blunting nerves, the technology related to potassium nitrate and potassium citrate is known, and in the case of potassium nitrate (containing 5% in dentifrice) Effectiveness is recognized. However, with these techniques, potassium ions must reach the dental pulp, but there are individual differences in the distance to the dental pulp, and also the type of teeth, and thus individual differences greatly affect how the effect appears. Therefore, the present situation is that development of a technique capable of retaining potassium ions on the tooth surface as long as possible is desired.

  As described above, there is still room for improvement in any technique, and a new technique capable of more effectively mitigating or preventing dentin hypersensitivity is desired.

JP 2003-026556 A JP 2003-073246 A JP 07-291844 A JP-T-2002-538192 Special Table 2002-505261 Japanese translation of PCT publication No. 2004-506663 JP 2000-281551 A Special Table 2002-505261 Special table 2004-525190 gazette JP-T-2002-512177 JP-T-2006-506436 Special table 2004-525190 gazette International Application PCT / JP2005 / 22831

  The present invention has been made in view of the above circumstances, and dramatically improves the deposition of minerals containing fluorine compounds in dentinal tubules, and is excellent in the effect of alleviating and preventing dentinal hypersensitivity due to dentinal tubules being constricted and blocked. And it aims at providing the composition for oral cavity with a favorable usability | use_condition.

As a result of intensive studies to achieve the above object, the present inventors have a proven track record in oral compositions such as dentifrices for the prevention of dental caries, and have a water solubility such as sodium fluoride that hardly affects the feeling of use. Paying attention to the mineral depositing action of the functional fluorine compound, (A) hydrolyzed silk having a number average molecular weight of 200 to 6,000, (B) a water-soluble fluorine compound, and (C) the following specific water-soluble condensed phosphoric acid In combination with an alkali metal salt of and / or an alkali metal salt of a water-soluble carboxylic acid, the content of the component (A) is 0.5 to 5% by mass, and the content of the component (B) is 0.02 to 5% by mass. %, The content of the component (C) is 0.5 to 3% by mass, and the total content of the components (A) and (C) is 1 to 6% by mass, thereby including the fluorine compound in the dentinal tubule Mineral deposition has improved dramatically and dentinal tubules have been narrowed and sealed The present invention has been found to provide an oral composition excellent in the effect of alleviating and preventing dentin hypersensitivity, and also excellent in use in the oral cavity as an oral composition such as a dentifrice or mouthwash. It came to make.

  For oral compositions containing a specific hydrolyzed silk, a technique of using this in combination with a fluorine compound has been proposed (see Patent Document 13), and a collagen enzyme present in dentin using hydrolyzed silk. It has been shown to be effective in the prevention of dentine caries by suppressing the oxidative degradation. The mechanism is that hydrolyzed silk has the property of being easily adsorbed and coated on collagen or dentin, and this adsorption / coating function prevents attack of degrading enzymes such as collagenase and suppresses the degradation of collagen. Conceivable.

  In the present invention, focusing on such adsorption / coating function of hydrolyzed silk, the effect of preventing / releasing dentin hypersensitivity can be improved. More specifically, when hydrolyzed silk and a fluorine compound are used in combination, the fluorine compound incorporated into the dentin is likely to stay for a long time due to the adsorption and coating of the hydrolyzed silk on the dentin. It was thought that the dentinal tubules were constricted and blocked, making it easier to form in tubules, and contributing to the prevention and relaxation effect of dentin hypersensitivity. Compared to the case of the compound alone, a high effect was not necessarily obtained.

Then, as a result of further intensive studies , hydrolyzed silk having a number average molecular weight of 200 to 6,000 , a water-soluble fluorine compound, an alkali metal salt of a specific water-soluble condensed phosphoric acid and / or an alkali metal salt of a water-soluble carboxylic acid, When a certain ratio is added, fluoroapatite is effectively deposited on the dentinal tubules compared to the case where any component is missing or the amount is inappropriate even if each component is used in combination. It has been found that the tubule is effectively effectively constricted and sealed, and a good feeling of use can be obtained, and the present invention has been achieved.

  In addition, about the action mechanism of water-soluble condensed phosphate and water-soluble carboxylate, it is guessed as follows. Hydrolyzed silk is water-soluble, but has the property of being easily adsorbed to collagen or dentin. When the above-mentioned water-soluble condensed phosphate and / or water-soluble carboxylate is added to the solution containing the hydrolyzed silk, the hydrolyzed silk is easily salted out and has an effect of adsorbing and covering collagen or dentin. It is thought that it will improve further. As a result, it is presumed that the fluorine compound taken into the dentin tends to stay for a long time, and that the formation of fluoroapatite in the dentinal tubule is greatly improved. One of the reasons why water-soluble condensed phosphates are excellent in such salting-out action is that water-soluble condensed phosphates are multi-ionic (more than minus 4 charges), so This is probably because the salting-out effect tends to appear at a relatively low concentration as compared with a single charge salt. On the other hand, regarding the carboxylate, it is presumed that a mechanism (for example, interaction between the hydrocarbon group of the carboxylate ion and the hydrolyzed silk) that is not necessarily explained only by the multi-charge ionicity is involved.

Accordingly, the present invention, (A) a number average molecular weight 200～6,000 of hydrolyzed silk, (B) a water-soluble fluorine compound, and (C) preparative Riporirin acid, polyphosphoric acid, lactic acid, malic acid, tartaric acid, malonic acid , it contains one or more selected from sodium and potassium salts of gluconic acid, 0.5 to 5% by weight content of the component (a), 0.02 to the amount of the component (B) 5% by mass, the content of component (C) is 0.5-3% by mass, and the total content of component (A) and component (C) is 1-6% by mass Offer things.

  The oral composition of the present invention can drastically improve the deposition of minerals containing fluorine compounds on dentinal tubules, and the dentinal tubules are effectively constricted and sealed to alleviate / prevent dentinal hypersensitivity. It is excellent in effect and has a good feeling of use, and is effective in preventing or alleviating dentine hypersensitivity.

  Hereinafter, the present invention will be described in more detail. The oral composition of the present invention comprises (A) hydrolyzed silk, (B) water-soluble fluorine compound, (C) water-soluble condensed phosphate and / or carboxylic acid. Contains salt.

The hydrolyzed silk (silk hydrolyzate) used in the present invention is obtained by purifying silk protein (for example, silk fibroin) obtained by refining silk thread sputtered from silkworm with acid / alkali, enzyme, oxidation / reducing agent, etc. It can be obtained by using and hydrolyzing.
It is known that the silk thread has fibroin in the center and sericin in the periphery, and the abundance ratio is generally fibroin: sericin = 70-80%: 20-30% (mass percentage). As for silk thread, first, silkworms produced at a sericulture farmhouse are dried and dried and then spun to produce raw silk, and then raw silk is scoured to obtain silk thread or silk fabric. The most common refining method is boiling in an aqueous solution containing an alkaline sodium salt or soap (alkaline soap refining). By this refining, sericin outside the silk thread is removed, and only the fibroin in the center is purified. Is done. Hydrolyzed silk can be obtained by hydrolyzing this fibroin (number average molecular weight: about 350,000) with an acid / alkali, enzyme, oxidizing / reducing agent, etc., but various molecular weights can be obtained depending on the degree of hydrolysis. Can be prepared.

Here, in the decomposition treatment with acid, for example, dilute acid (inorganic acid such as hydrochloric acid, phosphoric acid, sulfuric acid, or organic acid such as acetic acid, citric acid) is heated to about 60 to 120 ° C. and treated for 10 minutes or more. Is preferred.
The decomposition treatment with alkali is preferably performed by heating a dilute alkali solution (inorganic alkaline agent such as sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate) to about 60 to 180 ° C. for 10 minutes or more.

  The degradation treatment with an enzyme is preferably carried out in an enzyme solution having protease activity (for example, an enzyme such as pepsin or papain), and the treatment is preferably performed at about 10 to 60 ° C. for 10 minutes or more at each optimum pH.

The decomposition treatment with the redox agent is preferably performed for 10 minutes or more at about 10 to 100 ° C. in a diluted solution of the redox agent. As the redox agent, compounds such as sulfite, hydrogen peroxide, hypochlorite and hydrazine can be used.
In addition, the said hydrolysis process method may be performed by a single processing method, or may use two or more methods together.

  In the present invention, the hydrolyzate thus obtained is preferably purified (desalted, deodorized, decolorized, etc.) and used as hydrolyzed silk. This hydrolyzate contains molecules (amino acids, amino acid oligomers, peptides) having various molecular weights depending on the decomposition conditions and purification conditions, but any molecule having a number average molecular weight within a specific range is included. In other words, a higher effect can be obtained than in the case of silk protein that has not been hydrolyzed (for example, silk fibroin).

As the hydrolyzed silk of the present invention, a decomposed product having a number average molecular weight of 200 to 6,000 is used among silks obtained by hydrolysis under certain conditions as described above . This is preferably industrially easily available, more preferably a decomposed product having a number average molecular weight of 500 to 5,000, more preferably 500 to 1,000. When the number average molecular weight is less than 200, adsorptivity to teeth has a low film-forming property of some, such that low dentinal tubule stenosis-blockade effect. Film-forming properties exceeds 6,000 adsorptivity to the high tooth is reduced, dentinal tubules constriction-blockade effect is not such to exhibit satisfactory.

  The number average molecular weight is generally calculated by gel filtration chromatography (GPC) and analytical nitrogen value calculation. Polypeptide compounds such as hydrolyzed silk used in the present invention are determined by the latter method. It is preferable to use a calculated value. The number average molecular weight of the hydrolyzed silk is calculated by the following formula (1) based on the total nitrogen amount in the molecule, the amino nitrogen amount, and the average molecular weight of the constituent amino acids.

  In the above formula (1), the average molecular weight of the constituent amino acids is obtained by multiplying the abundance ratio (%) of the constituent amino acids obtained by ordinary amino acid analysis and the molecular weight of each amino acid. The first nitrogen determination method of the raw material standard general test method or gas chromatography (GC), and the amount of amino nitrogen can be measured by the formol titration method.

  A commercially available product can also be used as the hydrolyzed silk. Hydrolyzed silk is commercially available from various companies in grades with various number average molecular weights, and they can be used properly as needed. Examples of the hydrolyzed silk by phosphoric acid hydrolysis include silk BN-P (manufactured by NDC Co., Ltd., number average molecular weight 500), and as hydrolyzed silk by enzymatic hydrolysis, silk peptide M-500 (Cosmo Foods Co., Ltd.) Manufactured, number average molecular weight 500), hydrolyzed silk by other manufacturing methods, Promois (registered trademark) silk 1000p (manufactured by Seiwa Kasei Co., Ltd., number average molecular weight 1,000), silk peptide 5 (manufactured by Kanebo Co., Ltd.) , Number average molecular weight 1,500), silk powder FD (manufactured by Kanebo Co., Ltd., number average molecular weight 5,000), and the like. In consideration of the stability of blending into oral compositions such as dentifrices, hydrolyzed silk that has not been subjected to chemical modification such as cationic or nonionic properties can be suitably used.

  The blending amount of the hydrolyzed silk is 0.5 to 5% (mass%, hereinafter the same) of the whole composition, and preferably 0.5 to 3%. If the blending amount is less than 0.5%, a high dentinal tubule stenosis / sealing effect cannot be obtained. .

  Examples of the water-soluble fluorine compound used in the present invention include sodium fluoride, potassium fluoride, ammonium fluoride, tin fluoride, amine fluoride, sodium monofluorophosphate, potassium monofluorophosphate, sodium fluoride silicon, fluoride Silicon calcium etc. are mentioned, Especially sodium fluoride and sodium monofluorophosphate are preferable. You may use these individually by 1 type or in combination of 2 or more types.

The compounding amount of the fluorine compound is 0.02 to 5% of the whole composition, particularly 0.02 to 1.2% in the case of sodium fluoride , and 0.05 to 3.3% in the case of sodium monofluorophosphate. It is preferable to blend in the range of 8%. Furthermore, the compounding amount of the fluorine compound is preferably 100 to 5,000 ppm, particularly preferably 100 to 3,000 ppm as fluorine.
If the amount of the fluorine compound is less than 0.02%, dentinal tubule constriction-blockade effect can not be obtained satisfactorily, the dentinal tubules stenosis-blockade effect exceeds 5% tends to saturate.
Further, if the fluorine content is less than 100 ppm, a satisfactory fluorine dentinal tubule stenosis / sealing effect cannot be obtained, and if it exceeds 5,000 ppm, the dentinal tubule stenosis / sealing effect tends to be saturated.

Water-soluble condensed phosphates used in the present invention are those selected bets Riporirin acid, sodium salt of polyphosphoric acid, potassium salt.

As the water-soluble carboxylate, a water-soluble carboxylate having no off-flavor and off-flavor is preferable , and one selected from lactic acid, malic acid, tartaric acid, malonic acid , sodium salt of gluconic acid, and potassium salt is used.

  In the present invention, the above-mentioned water-soluble condensed phosphate and / or water-soluble carboxylate is blended as the component (C), and one kind may be blended alone or two or more kinds may be used in combination. Even if a phosphate or a water-soluble carboxylate is blended, a water-soluble condensed phosphate and a water-soluble carboxylate may be used in combination.

The total amount of the water-soluble condensed phosphate and / or the water-soluble carboxylate is 0.5 to 3% in the composition, preferably 1 to 2%. If the blending amount is less than 0.5%, a satisfactory dentinal tubule stenosis / sealing effect cannot be obtained, and if it exceeds 3%, the feeling of use becomes worse.
Moreover, when mix | blending water-soluble condensed phosphate, the compounding quantity is 0.5 to 3%, especially 1-2% is preferable, and when mix | blending water-soluble carboxylate, the compounding quantity is 0.5- 3%, especially 1-2% is preferred.

  In the present invention, the total amount of (A) hydrolyzed silk and (C) water-soluble condensed phosphate and / or water-soluble carboxylate is 1 to 6%, preferably 1.5 to 5%. is there. If it is less than 1%, the effect of hydrolyzed silk on dentinal tubule stenosis / sealing will not be sufficiently exerted, and if it exceeds 6%, the feeling of use will be poor.

  The oral composition of the present invention is a dentifrice such as toothpaste, toothpaste, liquid toothpaste, mouthwash, mouth freshener, gargle tablet, denture cleaner, troche, chewing gum, etc., especially toothpaste. It can be used as a dentifrice such as the like, and other components can be blended as optional components depending on the form and prepared by a usual method.

  As the optional component, a proper component corresponding to the type of oral composition is used. For example, abrasives, surfactants, binders, thickeners, sweeteners, preservatives, fragrances, colorants, pH adjusters, excipients, various medicinal ingredients, and the like can be blended.

  As the abrasive, for example, silica-based abrasive such as anhydrous silicic acid, aluminum hydroxide, aluminum oxide, aluminosilicate, dicalcium phosphate, insoluble sodium metaphosphate, insoluble potassium metaphosphate, titanium oxide, synthetic resin, etc. as required And preferably used (the amount is usually 3 to 90%).

  Examples of the surfactant include water-soluble salts of higher alkyl sulfates having 8 to 18 carbon atoms in the alkyl group such as sodium lauryl sulfate and sodium myristyl sulfate, fatty acid groups such as sodium lauryl monoglyceride sulfonate and sodium coconut monoglyceride sulfonate. A water-soluble salt of a higher fatty acid monoglyceride sulfonic acid having 10 to 18 carbon atoms, an anionic surfactant such as olefin sulfonic acid and paraffin sulfonic acid, and a fatty acid group such as stearyl monoglyceride, sucrose mono and dilaurate. 12-18 sucrose fatty acid ester, lactose fatty acid ester, lactitol fatty acid ester, maltitol fatty acid ester, stearic acid monoglyceride, polyoxyethylene sorbitan monolaurate Nonionic surfactants such as polyoxyethylene hydrogenated castor oil, sorbitan monostearate condensate added with about 60 mol of ethylene glycol, a polymer of ethylene oxide and propylene oxide, a derivative such as polyoxyethylene polyoxypropylene monolauryl ester, Amphoteric surfactants such as betaine type and amino acid type are used (normally 0.01 to 7%).

  Examples of the binder include carrageenan, sodium carboxymethylcellulose, methylcellulose, hydroxymethylcellulose, hydroxyethylcellulose, cellulose derivatives such as sodium carboxymethylhydroxyethylcellulose, alkali metal alginates such as sodium alginate, propylene glycol alginate, xanthan gum, tragacanth gum, caraya gum, arabic Formulated with gums such as gums, synthetic binders such as polyvinyl alcohol, sodium polyacrylate, carboxyvinyl polymer, polyvinylpyrrolidone, inorganic binders such as gelling silica, gelling aluminum silica, bee gum, and laponite (Mixing amount is usually 0.5 to 10%).

  As the thickener, polyhydric alcohols such as sorbit, glycerin, ethylene glycol, propylene glycol, 1,3-butylene glycol, polyethylene glycol, polypropylene glycol, xylit, maltite, lactit, sugar alcohol, etc. can be blended (blending amount) Usually 1-50%).

Sweeteners include sodium saccharin, stevioside, xylitol, neohesperidyl dihydrochalcone, glycyrrhizin, perilartine, thaumatin, aspartylphenylalanine methyl ester, p-methoxycinnamic aldehyde, sodium cyclamate, etc., and preservatives include p-hydroxymethyl Benzoic acid, p-hydroxyethyl benzoic acid, p-hydroxypropyl benzoic acid, p-hydroxybutyl benzoic acid, sodium benzoate, lower fatty acid monoglyceride, etc. Wintergreen oil, spearmint oil, peppermint oil, sassafras Oil, clove oil, eucalyptus oil, etc. may be blended. As the colorant, Blue No. 1, Yellow No. 4, titanium dioxide and the like can be blended in usual amounts.
Gelatin, peptone, albumin, brightener, silicone, and other components can be blended.

  Examples of medicinal ingredients include epsilon aminocaproic acid, tranexamic acid, dextranase, protease, mutanase, lysozyme, lytic enzyme, enzyme such as lytechenzyme, chlorhexidine salts, dihydrocholesterol, glycyrrhetin salts, glycyrrhetinic acid, caropeptide, vitamins, Active ingredients such as anti-plaque agents, antibacterial agents, hyposensitivity agents such as sodium chloride and potassium nitrate, and the like can be blended within a range that does not interfere with the effects of the present invention.

  EXAMPLES Hereinafter, although an experiment example, an Example, and a comparative example are shown and this invention is demonstrated concretely, this invention is not restrict | limited to the following Example. Note that% in the table is a mass percentage. Moreover, the compounding quantity in a table | surface showed what was converted into the pure part. The number average molecular weight of the hydrolyzed silk is a value calculated by the above formula (1) based on the total nitrogen amount in the molecule, the amino nitrogen amount, and the average molecular weight of the constituent amino acids.

[Experimental example]
A composition for the oral cavity having the composition shown below was prepared by the following method, and a stenosis / blocking test and usability evaluation of dentinal tubules were performed. The results are shown in Tables 1 and 2.

(1) Preparation of sample A boundary between a crown portion and a root portion of a human extracted tooth was cut to obtain a root portion. The surface of the tooth root was polished flat with # 1200 sandpaper to expose a new dentin surface. Next, using a dental diamond cutter in a direction perpendicular to the long axis of the root, the root was cut to a thickness of about 0.5 mm to obtain a dentin disk. Next, both sides of the disc (excluding the newly exposed dentin side) were coated with water-resistant nail polish (Neuve Neel Color RD8 Shiseido Co., Ltd.). The coated disc was immersed in a 0.5 mol / L EDTA solution (pH 7.4) for 4 minutes at room temperature to remove the smear layer clogged in the dentinal tubule and open the dentinal tubule (hereinafter referred to as “the dentinal tubule”). This is referred to as a dentin sample.) This condition was used as a model for the development of dentin hypersensitivity (An in vitro study of dentin sensitivity: The relation of dent in sensitivity and 68 of Jen in the dent in tubes. ).

(2) Preparation of test dentifrice composition In purified water, water-soluble components (glycerin, xylitol, sodium saccharin, etc.) and active ingredients (sodium fluoride, sodium monofluorophosphate, hydrolyzed silk, water-soluble) A condensed phase phosphate, water-soluble carboxylate, comparative component, etc.) were mixed and dissolved at room temperature. On the other hand, phase B was prepared by dissolving and dispersing sodium carboxymethylcellulose at room temperature in propylene glycol. Next, B phase was added and mixed in A phase under stirring, and C phase was prepared. In Phase C, fragrance, anhydrous silicic acid and sodium lauryl sulfate are mixed at room temperature using a 1.5 L kneader (manufactured by Ishiyama Kogakusho), depressurized to 5.3 kPa, defoamed, and 600 g of a dentifrice composition is obtained. Obtained. During the mixing, the pH was adjusted to 7.0 with sodium hydroxide or hydrochloric acid during mixing with a kneader.

Hydrolyzed silk is manufactured by NDC Co., Ltd. (trade name BN-P, number average molecular weight 500), Cosmo Foods Co., Ltd. (trade name: Silk Peptide M-500, number average molecular weight 500) and Co., Ltd. Seiwa Kasei Co., Ltd. (trade name: Promois silk 1000p, number average molecular weight 1,000) was used. Moreover, soybean protein hydrolyzate (Seiwa Kasei Co., Ltd., trade name Promois WS, number average molecular weight: 700) as protein hydrolyzate other than silk, and pork skin collagen (Nippon Ham (Nippon Ham) Co., Ltd., trade name NMP Collagen PS) was used as a comparative component. Water-soluble condensed phosphates, sodium tripolyphosphate (Na ₅ P ₃ O _10, molecular weight 368), and using sodium polyphosphate (both manufactured by Wako Pure Chemical Industries, Ltd.). As the water-soluble carboxylate , sodium lactate, sodium malate, sodium tartrate, sodium malonate, sodium gluconate, and potassium gluconate (all of which are reagents of Wako Pure Chemical Industries, Ltd.) were used. As these comparative components, potassium monohydrogen phosphate, sodium sulfate, and ammonium chloride (all reagents from Wako Pure Chemical Industries, Ltd.) were used.
The amounts of the above reagents were all shown as pure amounts.

Composition of test dentifrice composition:
Components (A) to (C), comparative components Amounts shown in Tables 1 and 2 Silicic anhydride 20.0%
Propylene glycol 3.0
Glycerin 30.0
Sodium carboxymethylcellulose 2.0
Xylitol 5.0
Sodium lauryl sulfate 1.0
Saccharin sodium 0.02
Fragrance 0.8
pH adjuster (sodium hydroxide or hydrochloric acid)
Purified water balance
Total 100.0%

(3) Treatment with test dentifrice composition The test dentifrice composition was diluted 4 times with distilled water, and the dentin sample was immersed in this diluted solution for 3 minutes (at room temperature). Thereafter, the sample was taken out, washed with distilled water for 5 seconds, excess distilled water was sucked off, and artificial saliva at 37 ° C. (CaCl ₂ = 1.5 mmol / L, KH ₂ PO ₄ = 5.0 mmol / L, acetic acid = 100 mmol / L, NaCl = 100 mmol / L, adjusted to pH 6.5 with 1N aqueous sodium hydroxide solution, all reagents are immersed in Wako Pure Chemical Industries, Ltd.) and calcified and deposited on dentinal tubules with fluorine compounds Was caused. After 7 hours, the sample was taken out from the artificial saliva, dipped again in the same manner with the test dentifrice composition, and then dipped again into the artificial saliva. This operation was performed twice a day and this was repeated for 5 days.

(4) Evaluation of dentinal tubule stenosis / blocking effect by electron microscope observation of the sample The dentinal tubule stenosis / blocking state of the sample after completion of the above treatment of the test dentifrice composition was observed with an electron microscope (S-3000N Hitachi High, Ltd.). (Technologies). That is, after the sample was naturally dried, carbon was vapor-deposited according to a conventional method to obtain an image (magnification: 5,000) of the stenosis / sealing state of the dentinal tubule opening on the dentin surface. 5 points were taken per sample, the number of dentinal tubules constricted and blocked (N _t ) was counted, and the ratio to the total number of dentinal tubules (N ₀ ): (N _t / N ₀ ) × 100 (%) The stenosis / blockage rate was calculated.
<Evaluation criteria for dentinal tubule stenosis / blocking effect>
A: Ivory tubule stenosis / blockage rate is 75% or more
○: Dentin tubule stenosis / blockage rate of 50% or more and less than 75%
Δ: Dentin tubule stenosis / blockage rate of 25% or more and less than 50%
X: Ivory tubule stenosis / blockage rate is less than 25%

(5) Evaluation of feeling of use A panel of 20 people was asked to use a test dentifrice composition as usual (about 3 minutes of brushing and then a light mouth rinse), and the feeling of use was evaluated according to the following evaluation criteria after use.
<Evaluation criteria for usability>
◎: 20 people have no problem in use
○: 17 to 19 people have no problem in use
X: 0 to 16 people have no problem in use

(6) Comprehensive evaluation Comprehensive evaluation was compared with Comparative Example 2 in which the effect of alleviating and preventing dentine hypersensitivity was sodium fluoride (0.21% as the most common compounding concentration for dentifrices) alone. The dentinal tubule stenosis / blocking effect of Comparative Example 2 is Δ, and the higher ones are ○ and ◎. Further, when the evaluation of the feeling of use is good (○ and ◎), that is, the combination of ◎ and ○, or a combination of ○ and ○ in the dentinal tubule stenosis / sealing effect and the feeling of use is preferable as a comprehensive evaluation (indicated with ○). When both were 両 者, it was evaluated that it was most preferable as a comprehensive evaluation (indicated by ×), and otherwise, it was evaluated as ×.

From the results of Tables 1 and 2, when any of the components (A) to (C) of the present invention is lacking or when the blending amount of these components is outside the range of the present invention, the dentinal tubule stenosis / sealing effect, feeling of use It turned out to be inferior to either.
Furthermore, in place of the hydrolyzed silk of the component (A) according to the present invention, soybean protein hydrolyzate as another protein hydrolyzate, pig skin collagen as non-hydrolyzed protein, and amino acid mixture (glutamic acid 10% ) Aspartic acid 10%, glycine 80%), the excellent dentinal tubule stenosis / sealing effect as obtained with hydrolyzed silk was not observed.
In addition, when (C) water-soluble condensed phosphate and / or water-soluble carboxylate is blended with other various inorganic salts such as potassium monohydrogen phosphate, sodium sulfate, or ammonium chloride, dentinal tubules are slightly Although a stenosis / blocking effect was observed, a sufficient effect was not obtained.
On the other hand, it was confirmed that the composition for oral cavity of the present invention has an excellent dentinal tubule stenosis / sealing effect and a good feeling of use.

  A composition for the oral cavity having the following composition was prepared in the same manner, and dentinal tubule stenosis / sealing effect, usability and comprehensive evaluation were similarly performed.

[Example 10 ] Dentifrice (Abrasive-free composition)
Sodium polyacrylate (Leogic 252L, Nippon Pure Chemicals Co., Ltd.) 1.5
70% Sorbit 55.0
Propylene glycol 5.0
Saccharin sodium 0.1
Sodium lauryl sulfate 1.5
Sodium benzoate 0.02
Methylparaben 0.1
Fragrance 0.8
Potassium nitrate 5.0
Hydrolyzed silk (Seiwa Kasei Co., Ltd., Promois silk 1000p, number average molecular weight 1,000)
1.5
Sodium fluoride 0.21
Sodium lactate 1.5
Purified water remaining
Total 100.0%
(Ivory tubule stenosis / blocking effect ◎, feeling of use ◎, comprehensive evaluation ◎)

[Example 11 ] Mouthwash hydrolyzed silk (NDC, BN-P, number average molecular weight 500)
0.8
Sodium fluoride 0.15
Sodium gluconate 1.0
Ethanol 8.0
Polyoxyethylene (60 mol) hydrogenated castor oil 2.0
Glycerin 10.0
Palmitoyl sarcosine sodium 0.1
Citric acid 0.01
Trisodium citrate 0.6
Saccharin sodium 0.1
Xylitol 5.0
Triclosan 0.05
0.1% green No.3 0.8
Fragrance 0.3
Purified water remaining
Total 100.0%
(Ivory tubule stenosis / blocking effect ○, feeling of use ◎, comprehensive evaluation ○)

[Example 12 ] Mouthwash hydrolyzed silk (Seiwa Kasei Co., Ltd., Promois silk 1000p, number average molecular weight 1,000)
1.5
Sodium monofluorophosphate 0.19
Sodium polyphosphate 1.0
Ethanol 8.0
Polyoxyethylene (60 mol) hydrogenated castor oil 2.0
Glycerin 10.0
Citric acid 0.01
Trisodium citrate 0.3
Saccharin sodium 0.1
Xylitol 5.0
Isopropylmethylphenol 0.1
Dextranase 0.3
Cetylpyridinium chloride 0.01
0.1% green No.3 0.8
Fragrance 0.3
Purified water remaining
Total 100.0%
(Ivory tubule stenosis / blocking effect ◎, feeling of use ◎, comprehensive evaluation ◎)

Claims (1)

(A) a number average molecular weight 200～6,000 of hydrolyzed silk, (B) a water-soluble fluorine compound, and (C) preparative Riporirin acid, polyphosphoric acid, lactic acid, malic acid, tartaric acid, malonic acid, sodium salt of gluconic acid And one or more selected from potassium salts, the content of the component (A) is 0.5 to 5% by mass, the content of the component (B) is 0.02 to 5% by mass, (C ) Component content is 0.5 to 3% by mass, and the total content of components (A) and (C) is 1 to 6% by mass.