Abstract: An oral composition for caries prophylaxis which comprises a highly soluble stannous compound such as stannous fluoride preferably in an amount of 0.03 to 5% by weight of the composition as stannous tin, a difficultly soluble stannous compound such as stannous pyrophosphate preferably in an amount of 0.05 to 10% by weight of the composition as stannous tin, a phytic acid compound such as sodium phytate preferably in an amount of 0.1 to 20% by weight of the composition, and the pH of the composition being preferably acidic. A portion of the difficultly soluble stannous compound may be in a precipitate form. The oral composition which may be used as dentifrices, prophylactic pastes, dental flosses and the like permits n.sup.2+ ions to exert its effect because the storage stability is high enough to maintain the increased concentration of active dissolved stannous ions in the composition for a prolonged period of time and can render the tooth enamel more resistant to acid attack when applied to teeth.

Abstract: An oral composition for caries prophylaxis which comprises 0.04 to 10% by weight of stannous fluoride and not less than 0.1% by weight of a phytic acid compound, the molar ratio of the phytic acid compound to stannous fluoride being in the range of from 0.01:1 to 4:1 and the composition being acidic, is effective in inhibiting dental caries and shows a prolonged effect after application. The oral composition may be used as mouthwashes, oral bands, topical solutions, cavity sealers, prophylactic pastes, dentifrices, dental flosses and the like.