Influence of the porosity and type of bioglass on the micro-mechanical and bioactive behavior of coated porous titanium substrates

Abstract

In this study, the best equilibrium among adherence, micro-mechanical properties and coating bioactivity of bioactive glasses (45S5 and 1393) on porous titanium substrates has been explored and their potential uses for bone tissue implants. Porous titanium discs with different porosities (30 and 60 vol.%) and pore size distributions (100–200 and 355–500 µm) were utilized to rationalize their influence on both properties and performance. It was corroborated that porous samples produced a reduction in micro-hardness (~ 2000–4000 N/mm2) and the elastic modulus (~25–50 GPa), obtaining values closer to those of human bones, as well as induced a beneficial role to integrate the coatings. On one hand, bioglass 1393 presented greater capacity for pore infiltration while 45S5 was more bioactive. The results explained the better adherence and microhardness for bioglass 1393 and the significant formation of hydroxyapatite and calcium phosphates of bioglass 45S5, confirmed by 29Si MAS NMR.