Oral care compositions and methods
This application relates to novel aqueous oral care compositions useful for combining and delivering incompatible stannous fluoride or stannous chloride and potassium salts in a high-water composition, for example, to provide effective caries prevention, protection against dental erosion, and relief from dental hypersensitivity. The compositions comprise stannous fluoride or stannous chloride, nitric acid or a water-soluble nitrate salt, a water-soluble alkali metal polyphosphate and more than 10% water, by weight of the composition.
1. A single-component oral care composition comprising
(i) 0.1 to 2% of stannous fluoride or stannous chloride, by weight of the composition;
(ii) 0.1 to 5% of nitric acid or a water-soluble nitrate salt, by weight of the composition;
(iii) 0.1 to 5% of a water-soluble alkali metal polyphosphate, by weight of the composition; and
(iv) more than 10% water, by weight of the composition;
wherein the composition comprises a molar ratio of the water-soluble alkali metal phosphate to the stannous fluoride or stannous chloride of 1:1 to 3:1; and a molar ratio of the nitric acid or water-soluble nitrate salt to the stannous fluoride or stannous chloride of 1:1 to 3:1.
2. The composition of claim 1 , wherein the water-soluble nitrate salt is selected from an alkali or alkaline earth metal nitrate, or zinc nitrate, silver nitrate, or ammonium nitrate.
3. The composition of claim 1 , wherein the water-soluble nitrate salt is selected from lithium nitrate, sodium nitrate, potassium nitrate, magnesium nitrate, and calcium nitrate.
4. The composition of claim 1 , wherein the water-soluble nitrate salt is potassium nitrate.
5. The composition of claim 1 , wherein the water-soluble alkali metal polyphosphate is selected from a pyrophosphate, tripolyphosphate, tetraphosphate or hexametaphosphate.
6. The composition of claim 5 , wherein the water-soluble alkali metal polyphosphate is selected from sodium pyrophosphate, potassium pyrophosphate, sodium tripolyphosphate and potassium tripolyphosphate.
7. The composition of claim 1 , wherein the water-soluble nitrate salt is potassium nitrate and the water-soluble alkali metal polyphosphate salt is tetrasodium pyrophosphate.
8. The composition of claim 1 , wherein the composition comprises a molar ratio of alkali metal polyphosphate to stannous fluoride or stannous chloride of at least 1:1.
9. The composition of claim 1 , wherein the composition comprises a molar ratio of nitric acid or water-soluble nitrate salt to stannous fluoride or stannous chloride of 1:1 to 2:1.
10. The composition of claim 1 , wherein the composition comprises from 0.1 to 2% stannous fluoride or stannous chloride, by weight of the composition; and wherein the composition comprises from 0.1 to 2% of the nitric acid or water-soluble nitrate salt, by weight of the composition; and wherein the composition comprises from 0.1 to 2% of the alkali metal polyphosphate salt, by weight of the composition.
11. The composition of claim 1 , wherein the composition comprises from 50% to 95% water, by weight of the composition.
12. The composition of claim 11 , wherein the composition comprises 70% to 95% water, by weight of the composition.
13. The composition of claim 1 , wherein the composition comprises from 10% to 50% water, by weight of the composition.
14. The composition of claim 1 ; wherein the composition comprises one or more humectants in a net amount of not more than 25% by weight of the composition.
15. The composition of claim 1 , wherein h composition is a single-phase composition.
16. The composition of claim 1 , wherein the composition is a dual phase composition.
17. The composition of claim 1 , wherein the composition is a mouthwash.
18. An oral care package comprising a composition according to claim 1 , wherein the package comprises a container comprising a single storage compartment, which compartment contains the composition, and a closure which seals the compartment.
19. A method of treatment or prevention of gingivitis, plaque, dental caries, and/or dental hypersensitivity, the method comprising the application to the oral cavity of a person in need thereof, of a composition according to claim 1 .
20. A method of stabilizing stannous ion in an aqueous oral care composition comprising the steps of (1) providing an aqueous vehicle, (2) adding to the aqueous vehicle a stannous ion source, (3) adding to the aqueous vehicle a nitrate ion source, and (4) adding to the aqueous vehicle a polyphosphate ion source, wherein the final composition is a single-component high-water composition, wherein the composition comprises a molar ratio of the water-soluble alkali metal phosphate to the stannous fluoride or stannous chloride of 1:1 to 3:1, and a molar ratio of the nitric acid or water-soluble nitrate salt to the stannous fluoride or stannous chloride of 1:1 to 3:1.
21. The composition of claim 1 , wherein the water-soluble nitrate salt is potassium nitrate, and wherein the alkali metal polyphosphate salt is tetrasodium pyrophosphate, and wherein the composition comprises stannous fluoride.
22. The composition of claim 21 , wherein the composition comprises about 0.45% by weight of stannous fluoride, 0.1-1% by weight of potassium nitrate, and 0.8-2% by weight of tetrasodium pyrophosphate.