Effects of Incorporation of Marine Derived Hydroxyapatite on the Microhardness and Surface Roughness of Two Glass-ionomer Cements

Background: The aim of this study was to evaluate the effects of incorporation of hydroxyapatite (HA) derived from cuttlefish bone on the microhardness (MH) and surface roughness (SR) of chemically cured, Fuji IX GP Extra and resin-modified glass-ionomer cement, Fuji II LC (GC Corporation, Tokyo, Japan). Methods: There were 4 groups for each GIC: one group without the addition of HA particles and three experimental groups with the addition of 2, 5 and 10 wt% HA. A sectional Teflon molds (8 mm diameter × 2 mm deep) were used to prepare 10 samples per group (n=80). The specimens were stored in distilled water at 37°C for 7 days before testing. The SR was measured using a contact type profilometer and the MH was measured with a Vickers micro-hardness tester at a load of 980 g for 15 s. Statistical analysis was performed using one-way ANOVA with Tukey post-hoc test. Results and Conclusion: Fuji II modified with 10 wt.% HA showed most favorable results with respect to MH. Comparison of materials with respect to SR showed that there is a difference between them (p <0.0001; ANOVA test). Fuji II and Fuji IX modified with HA showed higher surface roughness values which should be considered.