Synthesis and evaluation of factors affecting the in vitro bioactivity and antibacterial activity of bioactive glass ceramics

In the present study, two novel silicate glass-ceramics having chemical composition 38SiO₂–41CaO–6P₂O₅–($15-x$)Na₂O–$x$CaF₂ ($x=0$, 0.43 mol%) were synthesized. These glass derivatives were subjected to stimulated body fluid for 24 days in SBF under static condition at $37^{\circ }$C in order to evaluate the bioactive properties of specimens. The antibacterial activity of glass ceramics against three pathogenic bacteria was determined using the modified Kirby Bauer method. It was found that the antibacterial activity primarily depends on the dissolution rate; faster release of ions caused rapid increase in the pH of the solution. Antibacterial properties were found to be strongly affected by changes in the pH of supernatant. The in vitro bioactivity assays showed that both glass derivatives were capable of bonding with bone and secondly effectively inhibit bacteria. However, the glass ceramic without CaF₂ (B2) showed high dissolution rate, better bioactive ability and stronger antibacterial efficacy.