Salivary fluoride bioavailability after use of high‐fluoride dentifrices with different compositions: A short‐term randomized clinical trial

Abstract

AbstractObjectiveThe objective of the study was to evaluate the kinetics of salivary F bioavailability after the use of high‐fluoride dentifrices with different compositions and their amount of total soluble fluoride (TSF).MethodsA short‐term clinical randomized trial was performed in which 15 adult participants were randomly allocated into three groups: 5000 ppm F‐dentifrice, 5000 ppm F‐dentifrice + TCP (tri‐calcium phosphate) and 1450 ppm F‐dentifrice. Unstimulated saliva was collected at different times: baseline (before toothbrushing), immediately after brushing/water rinsing and at 5, 15 and 30 min and 1, 2, 4, 8 and 12 h after brushing. The TSF in dentifrices and saliva samples was analysed using an ion‐specific electrode. For statistical analysis, the paired t‐test and Kruskal–Wallis were used with Dunn's post‐test with a 95% confidence interval.ResultsThere was no significant difference between the declared TSF and that found in 5000 ppm F‐dentifrice and 1450 ppm F‐dentifrice (p ≥ 0.13); however, in the 5000 ppm F‐dentifrice + TCP, approximately 500 ppm less TSF was observed (p = 0.0024). The area under the curve (AUC, μg F/ml min−1) of both high‐fluoride dentifrices (321.7 ± 84.0 and 223.6 ± 55.1 for the one without and with TCP, respectively) was higher than the conventional one (89.97 ± 15.6) attesting a higher F‐bioavailability (p = 0.04). Furthermore, they were able to provide F‐salivary levels higher than the baseline for up to 2 h, while this time was 1 h for the 1450 ppm F‐dentifrice (p ≤ 0.003).ConclusionBoth high‐fluoride dentifrices similarly increased the salivary‐F bioavailability in comparison with 1450 ppm F‐dentifrice, despite the lower TSF presented by the dentifrice containing TCP.