Comparative evaluation of long-term fluoride release and antibacterial activity of an alkasite, nanoionomer, and glass ionomer restorative material – An in vitro study

BACKGROUND: The antibacterial activity of restorative material and the amount of fluoride released are interlinked. Hence, these are the two foremost properties to be studied. AIM: This study aimed to evaluate and compare the amount and pattern of fluoride release from Type IX GIC (GC HS posterior), nanoionomer (Ketac N100), and alkasite (Cention N), and the antibacterial activity against Streptococcus mutans at 24 and 48 h. SETTINGS AND DESIGN: This in vitro study was carried out in laboratory settings with six samples of each group for fluoride release using an ion-chromatography (IC) machine and five samples of each group for antibacterial activity using agar plates. MATERIALS AND METHODOLOGY: Samples of each group, Group I – Type IX GIC, Group II – nanoionomer, and Group III –alkasite, were prepared, immersed in 2 ml of artificial saliva, and fluoride release recorded using IC after 1, 7, 14, and 28 days intervals. The antibacterial activity against S. mutans was evaluated by placing samples of each group in the agar plates and measuring the diameter of zones of inhibition after 24 and 48 h. STATISTICAL ANALYSIS: One-way ANOVA test to check to mean differences between the groups and Tukey's honestly significant difference post hoc test for multiple intergroup comparisons (P = 0.05). RESULTS: The Type IX GIC showed the highest fluoride release after day1. However, nanoionomer showed the maximum fluoride release for the remaining days. The least amount of fluoride released was from the alkasite throughout the study. The antibacterial activity of nanoionomer was the highest, followed by Type IX GIC and alkasite at both 24 and 48 h. CONCLUSIONS: Nanoionomer showed the highest fluoride release and antibacterial activity.