BACKGROUND: Microhardness is one of the most imperative physical characteristics for comparative study of dental material. Under acidic conditions, restorative materials experience degradation over time, which can be envisaged by changes in the surface characteristics such as downturn in hardness. Thus, we aim to assess the effect of acidic drink on microhardness of zirconia-reinforced glass ionomer cement (GIC) and conventional GIC. MATERIALS AND METHODS: Zirconia-reinforced GIC and conventional GIC were chosen for this present study. A total of 60 study pellets were prepared and divided into two groups. Group A consisted of 30 pellets of zirconia-reinforced GIC and group B consisted of 30 pellets of conventional GIC. Baseline readings of microhardness were taken by Vickers hardness testing machine. The samples of groups A and B were further divided into three subgroups. Subgroup 1: immersed in distilled water for 1 day (control). Subgroup 2: immersed in Coca-Cola for 1 day. Subgroup 3: immersed in Coca-Cola for 7 days. Surface hardness values were recorded after 1 day for subgroups 1 and 2 and after 7 days for subgroup 3. RESULTS: The surface microhardness of zirconia-reinforced GIC was significantly higher than conventional GIC when intergroup comparison was made. There was no statistically significant difference in microhardness of both conventional GIC and zirconia-reinforced GIC from baseline values after 1 day of immersion either in distilled water or Coca-Cola. Microhardness of both conventional GIC and zirconia-reinforced GIC showed a significant rise from baseline after immersion in Coca-Cola after 7 days. CONCLUSION: Both the materials tested resisted acidic challenge
however, zirconia-reinforced GIC showed greater microhardness and can be considered as an alternative material of choice for conventional GIC. HOW TO CITE THIS ARTICLE: Kour T, Shahi P, Sogi S,