Immediate and delayed effects of an enzyme-dependent mineralizing mouthrinse on dental plaque

Twenty-two children aged 13 to 14 years rinsed for 3 X 1 min periods with a supersaturated calcium phosphate solution containing urea and monofluorophosphate. Plaque sampled one min after the last rinse showed a marked increase in water-extractable F and a smaller increase in Ca but no increase in water-extractable P. Water-insoluble forms of all three ions were elevated, however. The mean plaque pH was 8.28. Plaque sampled 24 hr after the last rinse showed significant increases in water-insoluble F and Ca only, and no increase in pH. The prompt pH rise and disappearance of water-soluble P suggest that, on exposure to the mineralizing solution, urea and monofluorophosphate are rapidly hydrolyzed by plaque enzymes to provide catabolites which cause the immediate precipitation of fluoridated calcium phosphate.