Effect of addition of titanium on structural, mechanical and biological properties of 45S5 glass-ceramic

The purpose of the present study was to evaluate the effect of addition of titanium on the structural, mechanical, and biological properties of sol-gel derived 45S5 bioactive glass-ceramic. For the synthesis of 45S5 glass ceramics, 5 and 10 mol% titanium were added to replace calcium named as Ti5 and Ti10, respectively. The structure of glass-ceramic was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FE-SEM), and energy dispersive X-ray spectroscopy (EDS). The ability of glass-ceramics to form hydroxyapatite (HA) was also evaluated using XRD, FTIR and FE-SEM/EDS following immersion in the simulated body fluid (SBF) for 1, 7 and 14 days. The ion release potential was also evaluated during the afore-mentioned immersion periods. Furthermore, the cell viability and alkaline phosphatase (ALP) activity of osteoblast-like cells exposed to the dissolved products of glass-ceramics were evaluated. The effect of addition of titanium on the mechanical properties was evaluated by measuring the compressive strength. Despite the slower rate of HA formation in Ti-containing groups during the first day of immersion, all groups showed similar results after 14 days. The addition of titanium to 45S5 bioactive glass-ceramic decreased the silicon and sodium ion release. Ti5 showed the highest level of cell viability and ALP activity. The compressive strength of 45S5 glass-ceramic significantly increased following addition of titanium, and Ti10 showed the highest value. In conclusion, the findings of this study support the synthesis of 45S5 glass-ceramic modified by addition of 5 mol% titanium ions due to improved mechanical and biological properties along with the ability to control solubility and ion release profile.