Preliminary comparison static and dynamic in vitro test of bioactivity of glass-ceramics

The bioactivity of glass ceramics with different amount of fluorapatite expressed as P2O5 content has been tested in vitro in static and dynamic regime. The paper reports the complete results of bioactivity test of glass-ceramics in static regime. XRD, SEM, and microprobe analysis were used to characterise the sample as well as to detect the presence of new phase onto the surface. The bioactivity, as demonstrated by the formation of new apatite layer, depends on P2O5 content. In static regime, the layer of hydroxyapatite develops by periodical deposition of spherical apatite bullet. In the dynamic test regime, the microstructure of apatite layer formed on the surface of sample is porous and grows as a result of continual reaction between the layer and fluid.