Effect of Aging on Hardness of Glass Ionomer, Resin-Modified Glass Ionomer, Giomer and Compomer Dental Restorative Materials

Abstract

Objective: To assess deionized water's aging effect on the hardness of four direct tooth colored dental filling
materials i.e., Glass Ionomer Cement, Resin Modified Glass Ionomer, Giomer and Compomer.
Study Design: An in vitro experimental study performed in triplicates.
Place and Duration of Study: The study was carried out at PG Laboratory, Department of Science of Dental
Materials, Army Medical College, Rawalpindi, Pakistan from February 2023 to August 2023.
Methods: Three disc-shaped samples (n=3) of 10 mm diameter and 1 mm thickness of each restorative material
were prepared using stainless steel molds per manufacturer's instructions. These disc-shaped samples were
then suspended in a 15 mL conical centrifuge tube containing 10 mL deionized water, followed by incubation in
a Forced Convection Laboratory Oven at 37 C where these were allowed to age over a period of 1-2 years.
Vickers Hardness of each sample was then checked at two-time intervals, i.e., after 24 h setting and after 2.5
years of ageing through the Micro Vickers Hardness Tester calibrated at 1Kgf (9.80 N) with dwell time of 10
seconds and light intensity 10.
Results: After one day (24 h) aging in deionized water, maximum mean Vickers hardness number (VHN) was
exhibited by Compomer (539.83±58.08 VHN) and least by GIC (175.75±24.47 VHN). After aging the sample for
912 days, maximum mean VHN was observed for GIC (420.67±99.66 VHN) and least by Compomer
(354.33±9.22 VHN).
Conclusion: RMGIC sustains its hardness on aging, hardness of GIC increases while that of Giomer and
Compomer decreases upon aging.

How to cite this: Gul H, Nayyer M, Junaid Y, Pasha M, Ejaz T, Liaqat U, Hassan SH. Effect of Aging on Hardness of Glass Ionomer, ResinModified Glass Ionomer, Giomer and Compomer Dental Restorative Materials. Life and Science. 2023; 4(4): 438-444. doi: http://doi.org/10.37185/LnS.1.1.437