Purpose: Individuals with cognitive impairments have an increased caries risk. Methods to prevent caries based on home care use of fluorides (F) presuppose a person's ability to cooperate and follow instructions. The aim of the present investigation was therefore to develop and evaluate an F-containing mucosa adhesive paste, which can be applied in home care by nursing staff. Materials and Methods: A cross-over, double-blind study design was used. The F concentrations were studied in whole saliva and interproximal fluid samples after application of a paste with 0.1% F based on the mucosa adhesive Orabase™. A placebo product without F was used as control. In six healthy adults the paste was applied before sleep in the vestibulum in the region of the first molar in each quadrant. The application was repeated during four nights. Results: Six hours after the application of the F paste the F concentrations in the interproximal areas and whole saliva had increased by 12-160 times compared to samples collected before the applications. The lower increase of the interproximal F concentrations was observed in the front region. Conclusions: The results suggest that an F-containing mucosa adhesive paste may be a promising vehicle for caries prevention in subjects unable to follow traditional home care recommendations. Keywords: fluoride, adhesive paste, home care, oral mucosa