Fluoride oral retention after professional topical application in children with caries activity: effect of the immediate water consumption.

Purpose: Since there is no agreement about the time patients must refrain from drinking or eating after a professional application of acidulated phosphate fluoride (APF), the purpose of this study was to evaluate the effect of water consumption on fluoride in saliva.

Methods: This blind randomized crossover in vivo study involved children who received a professional APF gel application followed by either drinking a glass of water (experimental group) or without rinsing, drinking, or eating (control group) for 2 hours. The nonstimulated saliva was collected at 0, 5, 15, 30, 60, and 120 minutes following the professional APF application. After a 7-day washout period, the control and treatment groups were switched.

Results: There was a statistically significant difference in the fluoride retention between groups in the times 0 to 5 minutes (P<.05).

Conclusions: The data suggest that the recommendation of asking patients to refrain from drinking water for 30 minutes following the professional APF application is excessive and can be reduced to 15 minutes.