Bioactive glass coatings for orthopedic metallic implants

The objective of this work is to develop bioactive glass coatings for metallic orthopedic implants. A new family of glasses in the SiO2–Na2O–K2O–CaO–MgO–P2O5 system has been synthesized and characterized. The glass properties (thermal expansion, softening and transformation temperatures, density and hardness) are in line with the predictions of established empirical models. The optimized firing conditions to fabricate coatings on Ti-based and Co–Cr alloys have been determined and related to the glass properties and the interfacial reactions. Excellent adhesion to alloys has been achieved through the formation of 100–200 nm thick interfacial layers (Ti5Si3 on Ti-based alloys and CrOx on Co–Cr). Finally, glass coatings, approximately 100 μm thick, have been fabricated onto commercial Ti alloy-based dental implants.