The bioactivity and ion release of titanium-containing glass polyalkenoate cements for medical applications

The ion release profiles and bioactivity of a series of Ti containing glass polyalkenoate cements. Characterization revealed each material to be amorphous with a T(g) in the region of 650-660°C. The network connectivity decreased (1.83-1.35) with the addition of TiO(2) which was also evident with analysis by X-ray photoelectron spectroscopy. Ion release from cements were determined using atomic absorption spectroscopy for zinc (Zn(2+)), calcium (Ca(2+)), strontium (Sr(2+)), Silica (Si(4+)) and titanium (Ti(4+)). Ions such as Zn(2+) (0.1-2.0 mg/l), Ca(2+) (2.0-8.3 mg/l,) Sr(2+) (0.1-3.9 mg/l), and Si(4+) (14-90 mg/l) were tested over 1-30 days. No Ti(4+) release was detected. Simulated body fluid revealed a CaP surface layer on each cement while cell culture testing of cement liquid extracts with TW-Z (5 mol% TiO(2)) produced the highest cell viability (161%) after 30 days. Direct contact testing of discs resulted in a decrease in cell viability of the each cement tested.