Evaluation of fluoride release and recharge potential of various types of glass ionomer cements

Open Access

Abstract

Background: Fluoride release from glass ionomer cements (GICs) plays a crucial role in preventing secondary caries by enhancing remineralization and inhibiting demineralization. The ability of GICs to undergo fluoride recharge further prolongs their cariostatic effect. This study aimed to evaluate and compare the fluoride release and recharge potential of different types of GICs under standardized laboratory conditions. Methods & Materials: An in-vitro experimental study was conducted in the Department of Science of Dental Materials, Dhaka Dental College, Dhaka, from 1 July 2024 to 30 June 2025. A total of 110 standardized specimens were prepared from conventional GIC (n = 37), resin-modified GIC (n = 36) and high-viscosity GIC (n = 37). Fluoride release was measured at 24 hours, 7 days, 14 days and 28 days using a fluoride ion-selective electrode. After baseline assessment, all specimens underwent fluoride recharge using a fluoridated toothpaste solution and post-recharge fluoride release was measured at the same intervals. Results: High-viscosity GIC showed the highest initial fluoride release (8.60 ± 1.05 ppm at 24 hours) and cumulative fluoride release up to 28 days (20.45 ± 2.10 ppm), followed by conventional GIC and resin-modified GIC. Post-recharge, high-viscosity GIC again exhibited the greatest fluoride release (7.20 ± 0.89 ppm at 24 hours). All differences among groups were statistically significant (p < 0.001). Conclusion: High-viscosity glass ionomer cement demonstrated superior fluoride release and recharge potential compared to conventional and resin-modified GICs, highlighting its suitability for patients with high caries risk.