Surface Roughness and Compressive Strength of Resin Modified Glass Ionomer Cement with the Addition of Zinc Oxide Nanoparticles

Introduction: Resin modified glass ionomer cement (RMGIC) is a hybrid ionomer cement by modifying glass ionomer cement (GIC) with resin. Restoration surface roughness is related to the accumulation of food debris on a restoration. The cement has a lower compressive strength than enamel and dentin. Efforts to reduce surface roughness and increase the compressive strength of RMGIC, by adding zinc oxide nanoparticles powder to RMGIC powder. Objective: This research aims to analyze RMGIC with the addition of zinc oxide nanoparticles powder as much as 1%-5% of the total mixture of RMGIC and zinc oxide nanoparticles powder on surface roughness and compressive strength. Method: This study used five treatment groups, namely groups 2, 3, 4, 5, and 6, each of which was given the addition of 1%, 2%, 3%, 4%, and 5% of the total mixture of RMGIC and zinc oxide nanoparticles powder, as well as group 1 (control) without the addition of zinc oxide nanoparticles powder. Each group consisted of 4 replications with cylindrical samples (10 mm diameter and 2 mm height) for surface roughness test and 4 replications with cylindrical samples (4 mm diameter and 6 mm height) for compressive strength test. Surface roughness was tested using surface roughness measurement and compressive strength was tested using a universal testing machine. Results: The results of statistical analysis of surface roughness and compressive strength tests showed significant differences between sample groups. Conclusion: The addition of zinc oxide nanoparticles powder on RMGIC reduces surface roughness and increases compressive strength.