Dynamics of Fluoride Bioavailability in the Biofilms of Different Oral Surfaces after Amine Fluoride and Sodium Fluoride Application

Abstract

It was the aim of this study to investigate differences in fluoride bioavailability in different oral areas after the application of amine fluoride (AmF) and sodium fluoride (NaF). The null hypothesis suggested no differences in the fluoride bioavailability. The tongue coating was removed and biofilm samples from the palate, oral floor and cheeks were collected. All subjects brushed their teeth with toothpaste containing AmF or NaF. Specimens were collected before, as well as immediately after and at 30 and 120 minutes after tooth brushing. The fluoride concentration was determined. The area under the curve was calculated for each location and compared statistically. In the tongue coating, fluoride concentration increased faster after NaF application than after AmF application. After 30 minutes, the fluoride concentration decreased and remained stable until 120 minutes after AmF application and returned to baseline after NaF application. The difference between the baseline and the endpoint measurements was statistically significant. The fluoride concentration in the tongue coating remained at a higher level compared with the baseline for up to 120 minutes post-brushing. This may indicate that the tongue coating is a major reservoir for fluoride bioavailability. The results also indicate an unequal fluoride distribution in the oral cavity.

Impact of customary fluoride rinsing solutions on the pellicle’s protective properties and bioadhesion in situ

“…As confirmed in this study, 500 ppm of sodium fluoride alone (B) could only slightly modify the erosion-preventive effect of the physiological pellicle. In comparison, the amphiphilic properties of amine fluoride such as contained in elmex Kariesschutz might have increased its affinity to pellicle proteins resulting in a slower clearance and a modification of the pellicle composition or –density, respectively 37 , 40 . Certainly, only the NaF/AmF/SnCl 2 -containing mouthrinse (D) could reduce the acid-induced calcium- and phosphate release of the physiological in situ pellicle significantly even under severe erosive conditions.…”

Randomized investigation of the bioavailability of fluoride in saliva after administration of sodium fluoride, amine fluoride and fluoride containing bioactive glass dentifrices

“…decreasing the development of the plaque [37] and has antibacterial activity against streptococci mutans [38]. which are accumulated in the oral biofilm [12].…”

“…It has been discussed whether salivary sediment acts as fluoride reservoir releasing fluoride slowly for a prolonged time. Fluoride bioavailability varies also in the different oral niches where different surfaces influence the fluoride bioavailability [12, 47, 48]. Other studies investigated the fluoride bioavailability in dental plaque and reported elevated fluoride concentrations after toothbrushing [44, 46].…”

“…However, the bioavailability of fluoride after tooth brushing is limited to a relatively short time interval. It has been shown, that the salivary fluoride level is back to baseline after tooth brushing with conventional fluoride containing dentifrices after 120 min [12–15]. On the other hand, high fluoride doses are toxic and may result in enamel disruption such as fluorosis [16–18].…”

Evaluation of novel nanoscaled metal fluorides on their ability to remineralize enamel caries lesions

“…Therefore, frequent applications of rather low concentrations of fluorides are recommended to inhibit demineralization and enhance remineralization 5 . The tongue may serve as an important fluoride reservoir, as well 6 . For remineralisation in vivo , the oral fluoride bioavailability depends of at least four factors: fluoride formulation, time after fluoride application, fluoride concentration in supernatant saliva and fluoride concentration in salivary sediment 7 .…”