Method: In a double-blind, crossover study, conducted in three phases of 7 days each, 24 volunteers, 3 and 4 years-old, brushed their teeth 3x/day with 0.3 g of a non-fluoride toothpaste (negative control), a toothpaste containing 1100 µg F/g (NaF) or toothpaste containing 1450 µg F/g (MFP). On the last 3 days, they were instructed to brush only the teeth occlusal surfaces, allowing biofilm accumulation. On the 7th day, dental biofilms were collected from buccal surfaces of posterior teeth before and 30 min after toothbrushing. The biofilm fluid was separated from the solids and fluoride concentration was determined by a microtechnic, using an inverted ion-specific electrode.
Result: No statistical difference in fluoride concentration in biofilm fluid before the toothbrushing was observed among groups (from 3.5±3.5 to 5.3±4.2). Mean (±SD;n=24) of fluoride concentration (µM) in dental biofilm fluid after brushing was statistically higher when fluoride toothpastes were used (12.0±10.2 and 6.1±3.0 for 1100 and 1450 µg F/g toothpaste, respectively) compared with non-fluoride (4.1±3.6).
Conclusion: The findings suggest that both toothpaste formulations most used by Brazilian children are able to enrich the dental biofilm fluid with fluoride ion having anticaries potential. Supported by CAPES (PNPD 23038.008386/2010-56)