The Effect of Various Elements Substitution on Properties of Bioactive Glass Scaffolds for Bone Tissue Engineering.

Aim: The aim of the present study was to synthesize and characterize sol-gel derived bioactive glass scaffold and evaluate the effect of substitution of Zirconium (Zr), Strontium (Sr), and Zinc (Zn) on the their bioactivity, biodegradability and mechanical properties. Materials and Methods: Bioactive glass scaffold samples with compositions 80% SiO2-15%CaO and 5% P2O5 and 75 % SiO2-15% CaO 5% P2O5 and 5% MO (in mol%) (M=Sr, Zr or Zn) were synthesized using the sol–gel combined with foam replication method. The scaffolds were characterized by DTA, XRD, SEM and FTIR spectroscopy. Their mechanical properties were measured and their bioactivity/ biodegradability were evaluated in simulating body fluid (SBF). Results: All the scaffolds showed no distinct difference in phase composition, macroporous structure, percent porosity or pore size distribution. Conclusions: Sr, Zr and Zn substitution decreased the mechanical properties of the bioglass system. Sr and Zr ions enhanced the formation of nano-structured hydroxycarbonate apatite (HCA) layer, whereas Zn ions diminished the bioactivity. Moreover, Sr ions increased the biodegradability of the bioglass system.