Preparation, Characterization and In vitro Cytotoxicity Assay of Calcium Silicate Derived SiO2 Rice Husk

Calcium silicate that is biocompatible may find application in the medical field, particularly in the replacement of bone grafts. One readily available and rich source of silica (SiO₂) for the production of silica-based compounds is rice husk waste. The three types of Indonesian rice husks that we use for our preparation and characterization of calcium silicate bioceramics are black (code: KS-H), red (code: KS-M), and white (code: KS-P). Additionally, we assess their cytocompatibility at various concentrations (0.5, 0.25, 0.1, and 0.01 mg/mL) using the methyl-thiazolyl-tetrazolium (MTT) assay on MG63 cell types. The triclinic anorthic phase of Wollastonite-1A, a kind of calcium silicate with the chemical formula CaSiO₃, with its rough, porous, uneven surface appearance, was present in all three samples. The 2-way ANOVA test's MTT assayfindings revealeda significant differences between samples at groups (p value of 0,000). The Tuckey test results based on the sample group showed a significant difference (p < 0,05) in cell viability between the KS-H and Control group,however, the ISO 10993-5 considered no toxic properties based on the mean cell viability of all test materials at different concentrations (0.5; 0.25; 0.1; and 0.01 mg/mL) (78.72%-123.51%). We may conclude that the three calcium silicates prepared in this study are not cytotoxic and have potential used in medical and dental application.