In-vitro Comparison of Cytotoxicity of Two Bioactive Glasses in Micropowder and Nanopowder forms

The cytotoxicity of the biomaterials is a key issue that should be addressed prior to pre-clinical applications. This study was designed to evaluate and compare the cytotoxixity of two forms of bioactive glasses:nanopowder and micropowder. Human HGF1-PI53 gingival fibroblast cells were used to evaluate the cytotoxicity of 0.5, 1, 1.5, 2, 5, 10, 15 and 20 mg/ mL concentrations of the two bioactive glasses via MTT assay. The results were statistically analyzed using analysis of variance and Tukey's test. A p-value less than 0.05 was considered statistically significant. Results showed that two bioactive glasses had statistically significant differences at 5, 10, 15 and 20 mg/mL concentrations (p-value < 0.05) and there was no correlation between time and cell cytotoxicity of bioactive glasses (p-value > 0.05), using t-test and Spearman's correlation coefficient. We conclude that that cytotoxicity of nanopowder bioactive glass at concentrations ≤ 2 mg/mL was similar to micropowder bioactive glass at 24 and 48 h, however, it is more cytotoxic at concentrations ≥ 5 mg/mL in the first 48 h of applications.