Amounts of Fluoride Recharge in Three Glass Ionomer Luting Agents in Different Times

In order to decrease the risk of dental caries and improve exposure of the teeth to fluoride, glass ionomer cements were introduced in restorative dentistry. Since fluoride releases from some dental materials, the gradual reuptake ability of fluoride in these cements is important in the long-term. In this study we intended to compare the amount of fluoride release in three common glass ionomer cements (FUJI 1, SDS, and FUJI PLUS) at 1,3,7,14 and 28 days. First, 24 disc shaped samples were fabricated from FUJI 1, SDS and FUJI PLUS glass ionomer cements. The discs were, then, drained from fluoride ions in a period of 56 days. Discs were randomly selected and, then, divided into control and experimental groups. In the experimental groups, each sample was dried and exposed to Colgate Total 1000 ppm fluoride toothpaste; afterwards, they were washed and stored in distilled water at 37°C. Amounts of fluoride ion release were evaluated at 1, 3,7,14 and 28 days for all the experimental samples. In the control groups, the same procedure was done but with no exposure to fluoride. Differences in the release of fluoride ion from the tested products were evaluated using two-way analysis of variance (ANOVA) and the mixed model. A P- value of <0.05 was considered statistically significant. There were statistically significant differences between the experimental and control groups in all three materials during the 28-day experiment. The amount of fluoride release increased from day 1 to 7 and then decreased up to day 28. On days 1, 3 and 7, SDS had the largest and Fuji I had the lowest amount of fluoride release and on days 14 and 28 the largest amount of fluoride release was seen in FUJI PLUS, SDS and FUJI I, respectively. SDS as a newly released and less expensive glass ionomer can release fluoride ions as effectively as FUJI PLUS. All glass ionomer cements evaluated in this study may be effectively recharged with fluoride ions in order to effectively release them in time to aid tooth remineralization.