The Effect of Different Coating Agents on the Microhardness, Water Sorption, and Solubility of EQUIA Forte® HT

Objective: This study aimed to assess the effect of four different surface-coating agents on the microhardness, water sorption, and solubility of the highly viscous glass ionomer cement EQUIA Forte® HT. Materials and methods: A total of 100 cylindrical EQUIA Forte® HT samples were examined, with 50 tested for Vickers hardness and the other 50 for water sorption and solubility. For each test, the specimens were divided into five groups (10 specimens/group) according to coating method: Group 1—no coating (control), Group 2—EQUIA Forte® Coat, Group 3—Single Bond™ Universal Adhesive, Group 4—ExciTE®F adhesive, and Group 5—petroleum jelly. Data were analyzed using the paired t-test, one-way analysis of variance, and Tukey’s post hoc test for multiple comparisons. Statistical significance was set at p < 0.05. Results: The mean microhardness of the coated groups was significantly higher than that of the uncoated group. Moreover, a significant difference in the microhardness value was detected between the coated groups. Furthermore, EQUIA Forte® Coat had the highest mean hardness value. The mean water sorption at 7 days showed that EQUIA Forte® Coat had the lowest values. In terms of water solubility, a statistically significant difference was found between no coating and all groups except EQUIA Forte®, between Single Bond Universal Adhesive and petroleum jelly, between petroleum jelly and EQUIA Forte Coat, and between EQUIA Forte® Coat and ExciTE®F. Conclusions: The study revealed that all coating agents significantly increased the microhardness of EQUIA Forte® HT, with EQUIA Forte® Coat showing the highest hardness and the lowest water sorption values.