Hydrogel compositions for tooth whitening
View Patent ↗A composition is provided, wherein the composition comprises a water-swellable, water-insoluble polymer, a blend of a hydrophilic polymer and a complementary oligomer capable of hydrogen bonding to the hydrophilic polymer, and a whitening agent, preferably a peroxide. The composition finds utility as a tooth whitening composition and is applied to the teeth in need of whitening, and then removed when the degree of whitening has been achieved. In certain embodiments, the composition is translucent. Methods for preparing and using the compositions are also disclosed.
1. An in-vivo film forming liquid teeth whitening composition comprising:
(a) 2-6 wt % of a water-swellable, water-insoluble acrylate-based polymer or copolymer comprising monomers selected from acrylic acid, methacrylic acid, methyl acrylate, ethyl acrylate, methyl methacrylate, and ethyl methacrylate;
(b) 4-10 wt % of a poly(N-vinyl lactam);
(c) 0.5-10 wt % of a polyalkylene glycol having a molecular weight ranging from about 300 to about 600 daltons, and
(d) 1-30 wt % of a whitening agent,
dissolved in a solvent mixture comprising water and a lower alcohol,
wherein, the liquid composition upon application to the surface of the teeth and evaporation of the lower alcohol, forms a hydrogel film that is insoluble or slowly soluble in saliva at body temperature to thereby remain on the teeth surface for a period of over at least 10 minutes.
2. The composition of claim 1 wherein the water-swellable, water-insoluble copolymer is a copolymer of methacrylic acid and methyl methacrylate or is a copolymer of methacrylic acid and ethyl acrylate.
3. The composition of claim 1 , wherein the acrylate-based polymer or copolymer is selected from the group consisting of (dimethylaminoethyl methacrylate-butyl methacrylate-methyl methacrylate copolymers, methacrylic acid-methyl methacrylate copolymers, 1:1, methacrylic acid-methyl methacrylate copolymers, 1:2, ethyl acrylate-methyl methacrylate-methacrylic acid ester with quaternary ammonium groups copolymers, 1:2:0.2, ethyl acrylate-methyl methacrylate-methacrylic acid ester with quaternary ammonium groups copolymers, 1:2:0.1 and ethyl acrylate-methyl methacrylate copolymers, 2:1).
4. The composition of claim 3 , wherein the acrylate-based polymer or copolymer is a methacrylic acid-methyl methacrylate copolymer.
5. The composition of claim 4 , wherein the copolymer has a ratio of free carboxyl groups to ester groups in the range of about 1:1 to 1:2.
6. The composition of claim 1 , wherein the poly(N-vinyl lactam) is selected from the group consisting of polyvinyl pyrrolidone, polyvinyl caprolactam, and blends thereof.
7. The composition of claim 6 , wherein the poly(N-vinyl lactam) is polyvinyl pyrrolidone.
8. The composition of claim 6 , wherein the poly(N-vinyl lactam) is polyvinyl caprolactam.
9. The composition of claim 1 , wherein the poly(N-vinyl lactam) has a number average molecular weight in the range of approximately 100,000 to 2,000,000.
10. The composition of claim 9 , wherein the poly(N-vinyl lactam) has a number average molecular weight in the range of approximately 500,000 to 1,500,000.
11. The composition of claim 1 , wherein the polyalkylene glycol has a molecular weight of about 400.
12. The composition of claim 1 , wherein the polyalkylene glycol is selected from the group consisting of carboxyl-terminated polyalkylene glycols and amino-terminated polyalkylene glycols.
13. The composition of claim 12 , wherein the polyalkylene glycol is selected from the group consisting of polyethylene glycol and carboxyl-terminated polyethylene glycol.
14. The composition of claim 13 , wherein the polyalkylene glycol is polyethylene glycol.
15. The composition of claim 1 , wherein the whitening agent is selected from the group consisting of peroxides, metal chlorites, perborates, percarbonates, peroxyacids, and combinations thereof.
16. The composition of claim 15 , wherein the whitening agent is a peroxide selected from the group consisting of hydrogen peroxide, calcium peroxide, carbamide peroxide, and mixtures thereof.
17. The composition of claim 15 , wherein the peroxide is an organic peroxide.
18. The composition of claim 17 , wherein the organic peroxide is selected from the group consisting of dialkyl peroxides, diacyl peroxides, peresters, perdicarbonates, ketone peroxides, and hydroperoxides.
19. The composition of claim 18 , wherein the dialkyl peroxide is t-butyl peroxide or 2,2 bis(t-butylperoxy)propane.
20. The composition of claim 18 , wherein the diacyl peroxide is benzoyl peroxide or acetyl peroxide.
21. The composition of claim 18 , wherein the perester is t-butyl perbenzoate or t-butyl per-2-ethylhexanoate.
22. The composition of claim 18 , wherein the perdicarbonate is dicetyl peroxy dicarbonate or dicyclohexyl peroxy dicarbonate.
23. The composition of claim 18 , wherein the ketone peroxide is cyclohexanone peroxide or methylethylketone peroxide.
24. The composition of claim 18 , wherein the hydroperoxide is cumene hydroperoxide or tert-butyl hydroperoxide.
25. The composition of claim 1 , further comprising a flavorant.
26. The composition of claim 25 , wherein the flavorant is selected from the group consisting of wintergreen, peppermint, spearmint, menthol, fruit flavors, vanilla, cinnamon, spices, flavor oils and oleoresins, and combinations thereof.
27. The composition of claim 1 , further comprising a sweetener selected from the group consisting of sucrose, fructose, aspartame, xylitol and saccharine.
28. The composition of claim 1 , further comprising at least one additive selected from the group consisting of fillers, preservatives, pH regulators, softeners, thickeners, colorants, pigments, dyes, refractive particles, flavorants, sweeteners, stabilizers, toughening agents, detackifiers, and permeation enhancers.
29. The composition of claim 1 , wherein the composition is translucent.
30. The composition of claim 28 , which further comprises an absorbent filler.
31. A method for whitening teeth comprising: applying the composition of claim 1 to at least a portion of the surface of one or more teeth, and maintaining the composition on the surface of the one or more teeth for a desired period of time, to thereby achieve a desired degree of whitening.
32. The method of claim 31 , wherein the desired period of time is predetermined.
33. The method of claim 32 , wherein the predetermined period of time is from about 10 minutes to about 24 hours.
34. The method of claim 33 , wherein the predetermined period of time is from about 10 minutes to about 8 hours.
35. The method of claim 34 , wherein the predetermined period of time is about 30 minutes to 1 hour.
36. The method of claim 31 , wherein the composition is applied by the user.
37. The method of claim 31 , wherein the composition is applied by finger, directly from a container comprising the composition, by brush or by applicator.
38. The composition of claim 1 , wherein the composition forms a continuous integrated viscous swollen gel coating separated from a liquid solution by a sharp phase boundary upon contact with aqueous media when characterized in-vitro by wedge microinterferometry.
39. The composition of claim 1 , wherein the solvent mixture comprises water and ethanol.
40. The method of claim 31 , further comprising, after the maintaining step, removing the hydrogel film composition from the surface of the one or more teeth.
41. The method of claim 40 , wherein the removing is by dissolution of the hydrogel film composition in saliva over time.
42. The method of claim 40 , wherein the removing is by conventional tooth cleansing methods.
43. The liquid composition of claim 1 , wherein components of the composition are miscible upon solvent evaporation.