Effects of rinsing with arginine bicarbonate and urea solutions on initial enamel lesions in situ.

OBJECTIVE: The aim of this study was to investigate the effects of rinsing with arginine or urea solution on initial enamel lesions in situ. METHODS: Fourteen subjects who wore mandibular removable partial dentures embedded with bovine enamel blocks with artificial enamel lesions were included. The experiment included four 4-week rinsing periods with a 10-day washout period between each rinsing period. In each rinsing period, the subjects rinsed after meal or snack using water, or 2% arginine bicarbonate, or 1% urea, or 0.05% NaF solution, five times daily. The mineralization changes of the enamel lesions were assessed using quantitative light-induced fluorescence. RESULTS: All groups except the water group showed a statistically significant decrease in the fluorescence loss after treatment, compared with their respective baseline. Although both the arginine group and urea group showed more decrease in fluorescence loss than that of the water group, the decrease was not statistically significantly different from that of the water group. The decrease in fluorescence loss of the NaF group was statistically significant than that of the water group, arginine group, and urea group. CONCLUSION: Rinsing with arginine or urea solution offers limited remineralizing benefit to enamel lesions over a period of 4-week time.