The biologic availability of fluoride from alginate impressions and APF gel applications in children.

Ten child volunteers received routine alginate impressions and APF gel topical applications during separate visits. Whole saliva, urine, and surface enamel fluoride concentrations were measured before and after these procedures. Significant increases in salivary, urinary, and enamel fluoride concentrations were observed following APF gel application but only in whole saliva following alginate impressions.