[Fluoride retention and clearance after rinsing with fluoridated mouthwashes].

Oral fluoride clearance and oral fluoride retention were studied in 12 adult volunteers. 5 different mouthrinses were used. The test agents, in part available on the market, includes two Candida mouthrinses containing 1508 and 330 ppm F, respectively, Act containing 308 ppm F, a zinc fluoride-hexetidine (ZH) combination containing 287 ppm F, and an amine fluoride 297/SnF2 (AmF/SnF2) combination containing 241 ppm F. The volunteers rinsed with 10 ml of the above solutions for 30 s each. The oral fluoride concentration was reduced to 1 ppm 99 min after rinsing with Candida original. With the AmF/SnF2 solution, the oral fluoride concentration remained above 1 ppm for 39 min, and for about 20 min after rinsing with Candida reduced, ZH and Act. With both Candida original and ZH significant fluoride levels in the oral fluid were still found after 3 h, while with AmF/SnF2 and Act significant fluoride levels lasted for 2 h. A specific clearance value was determined for each mouthrinse, reflecting the ability of the agent to remain attached to the oral structures. The AmF/SnF2-rinse had a rapid clearance value. About 9 to 17% of the fluoride brought into the oral cavity were not expectorated. For the mouthrinses containing 0.05% NaF the retention was about 0.4 mg F. This value is considered to be harmless. Mouthrinses used after the application of a monofluorophosphate-dentifrice helped to increase the relatively low oral fluid fluoride level. Rinsing with the test agents after brushing with the amine fluoride dentifrice (Elmex) produced no significantly increased fluoride levels. In-between meals eliminated the oral fluoride concentration rapidly.