Mechanical Properties of High Viscosity Glass Ionomer and Glass Hybrid Restorative Materials

Objectives: to determine the mechanical properties of hybrid and high-viscosity glass ionomer cements. Compressive strength and hardness of three glass ionomer cements (GIC) were measured: Ketac (TM) Universal Aplicap (TM), EQUIA Fil (R) and EQUIA FORTE Fil (R), and the SEM sample analysis were performed. Material and Methods: The samples for measuring the compressive strength were prepared using silicone molds with standard dimensions of 6 mm x 4 mm and stored in deionized water for five days, while the samples for hardness measurement were prepared using Teflon molds with a cylindrical opening in the middle, dimensions 2 mm in height and 5 mm in width. For each material, one sample was made (n = 1) and stored in deionized water at 37 degrees C for 25 days. A representative sample of each material was analyzed using SEM. For the comparison of obtained values, the ANOVA test was used, while Tukey test was used for the multiple comparison. Results: There were no significant differences between the compressive strength of the three tested materials (p < 0.05). The hardness values were: 157 HV0,2 for Ketac (TM) Universal Aplicap (TM), 47 HV0,2 for EQUIA Fil (R) and 39 HV0,2 for EQUIA FORTE Fil (R), respectively, and were significantly different, implying that Ketac (TM) Universal Aplicap (TM) has much higher hardness values than the other materials tested. SEM sample analysis revealed similar fracture modes of the tested materials. Conclusion: It was concluded that there were no statistically significant differences in compressive strength and fracture modes between the tested materials, while Ketac (TM) Universal Aplicap (TM) hardness results were significantly higher than the ones measured for EQUIA Fil (R) and EQUIA FORTE Fil (R).