Influence of Resin Coating on Fluoride Release of Fuji VII

Objective: The aim of this study was to analyse the influence of a resin coating on the fluoride release from an auto-cure, regular setting glass ionomer cement (Fuji VII). Methods: Twenty eight specimens were prepared in brass rings 8.90mm in diameter and 2.15mm thick. The specimens were allowed to remain untouched for 7 minutes, after which they were removed from the brass rings. Fourteen of the specimens were completely coated with Optibond Solo. All the specimens were stored in distilled water at 37ºC for 24 hours. The water was refreshed daily and measurements of fluoride release were made at daily intervals using a combination fluoride ion-selective electrode. Results: Over the initial test period of 17 days the fluoride release was greater from the uncoated specimens than from the resin coated ones. About 1.5 ug/mm² was released during the first day from the uncoated samples but only approximately 0.5 ug/mm² from the resin coated samples. Most of the fluoride was released over the first approximately 5 days but after 9 days only a fraction of the first day was released. Conclusions: Resin coating of glass ionomers to enhance their surface properties allowed the release of fluoride ions even though at a reduced rate. This relatively low amount of fluoride may result in sufficiently high levels of fluoride in a microleakage gap to stimulate remineralization as well as anti-microbial activities.