Evaluation of fluoride and calcium ion release and fluoride recharge capacity of glass-ionomer materials modified with experimental bioactive glass

The aim of the study was to evaluate fluoride(F) release and re-release after recharging, and calcium(Ca) release from Fuji IX(Fuji) and Equia Forte HT(E) modified with 5wt% of experimental bioactive glasses BAG and BAG-F. F release was recorded over 91 days, and F re-release over 21 days in six groups (n = 12): (1) Fuji; (2) Fuji BAG; (3) Fuji BAG-F; (4) E; (5) E BAG; (6) E BAG-F. Ca release was recorded over a period of 21 days in samples stored in distilled water or lactic acid(LA) in eight groups (n = 10): (1) Fuji; (2) Fuji LA; (3) Fuji BAG-F; (4) Fuji BAG-F LA; (5) E; (6) E LA; (7) E BAG-F; (8) E BAG-F LA. F and Ca were recorded using ion selective electrodes. ANOVA and LSD test were performed at α = 0.05. F release was significantly higher in modified variants of Fuji and Equia (BAG-F > BAG > original) at all time points, before and after recharging (p < 0.001). Increased F release in modifications was more pronounced in E than in Fuji (p < 0.05). F release after recharging was lower but dropped more slowly in both materials and modifications. The differences in Ca release were significant regarding material and time intervals (p < 0.001). The highest Ca release was recorded in Fuji BAG-F LA, followed by Fuji BAG-F, Fuji LA, Fuji, E BAG-F LA, E BAG-F, E LA, and E.