Development of novel bioactive glass-ceramics in the Na2O/K2O-CaO-MgO-SiO2-P2O5-CaF2 system

This paper reports on the development of novel bioactive glass-ceramics (GCs) in the Na₂O/K₂O-CaO-MgO-SiO₂-P₂O₅-CaF₂ system for dental implant applications. The influence of partial substitution of Mg for Ca and of complete substitution of K for Na on bioactivity performance, mechanical properties, and aesthetics, was thoroughly investigated. Dense and well-crystallized GCs were produced, where the K-free GCs were comprised of diopside, wollastonite, and fluorapatite, and the K-containing ones consisted of diopside, fluorapatite, and alpha-potassium magnesium silicate (α-PMS). The experimental results suggest that wollastonite and α-PMS favored the bioactivity performance, reflected in the ability of the GCs to spontaneously form hydroxyapatite on their surface. It was also demonstrated that the above substitutions in the produced GCs enable suitable tuning of their mechanical properties in order to approach the physical properties of natural jaw bones (i.e. reduction of modulus of elasticity, increase of fracture toughness) better than the commercial zirconia and titanium implants.