Innovative fabrication of Zn-doped 45S5 glass-ceramic scaffolds using eggshell: Physico-mechanical properties and bioactivity assessment

In the present study, glass-ceramics scaffolds doped with different amounts of zinc oxide were fabricated. In this regard, eggshell, as a natural porogen and environmentally friendly material, was considered to fabricate scaffolds. Physico-mechanical properties, along with bioactivity of the fabricated scaffolds, were evaluated precisely. To this purpose, all glass powders were prepared through melt quenching and subsequent milling. Scaffold specimens were prepared by heat treating mixtures of powdered glass with different amounts of eggshell. Based on the obtained results, the main crystalline phase of the studied scaffolds is sodium calcium silicate. With the increase in the amount of zinc oxide in the glass composition, the sodium zinc silicate phase is also formed. Considering the compressive strength, stability of the scaffold samples, and their physical properties, the optimal amount of eggshell used in scaffold preparation was determined to be 35% by weight. In the most promising specimen, porosity was achieved at 55%. After immersion in simulated body fluid for 28 days, all scaffolds showed apatite formation ability, confirming their acceptable bioactivity.