Quantitation of Fluoride Released from Dental Floss Impregnated with Stannous Fluoride

Objective: Excessive fluoride (F) ingestion has been known to cause enamel fluorosis. Recently, dental floss impregnated with SnF2 is available commercially to transport topical F to the high caries-risk interproximal areas. This study is designed to evaluate how much F may be released during simulated flossing process. Methods: FlossRx which delivers 2-4mg SnF2 per two 21"-strand, were provided by Omnii Oral Pharmaceuticals. Fourteen decay-free human teeth (4 molars, 4 premolars, 6 anteriors) were set in Microstone and were wet with artificial saliva. Flossing was performed on these teeth in replicates of 5, with thorough cleaning and rinsing of these teeth with deionized water between each flossing. F retained on dental floss after flossing was determined by soaking in 100ml of deionized and distilled water for 24 hrs. The quantitative difference between F extracted from control dental floss and those extracted from dental floss that has been used for flossing represented amount of F released during flossing. F analysis was carried out with a F-specific electrode and an Orion millivoltmeter. Result: Amount of F released per FlossRx strand was 49.3, 60.3, and 88.2 mcg when flossing was performed for 45, 90, 180 sec. respectively. Conclusion: This study showed that considerable amount of F could be released from flossing with SnF2-impregnated dental floss. Use of F-containing dental floss in children should be carefully monitored to reduce the risk of enamel fluorosis.