Rapid Casting of Biodegradable Porous Magnesium Scaffolds and Electrophoretic Deposition of 45S5 Bioactive Glass Nanoparticles Coatings on Porous Scaffolds: Characterization and In Vitro Bioactivity Analysis

In this study, three-dimensional (3D), biodegradable, porous magnesium (Mg) alloy scaffolds were fabricated using the rapid casting method. The casting models were welded onto a wax rod to produce a casting tree using a stereolithography (SLA) machine with castable wax. The model has a high surface area and porosity. The pore size, strut thickness, and porosity of the 3D porous scaffolds are 1.5 mm, 0.45 mm, and 71.68%, respectively. The relative density and surface area-to-volume ratio are also 3.53 and 5.43, respectively. The pure phase of 45S5 bioglass (BG) nanomaterial was successfully synthesized using the sol-gel method. The 45S5 BG was characterized using transmission electron microscope (TEM), energy-dispersive X-ray analysis (EDX), X-ray diffraction analysis (XRD), Fourier-transform infrared spectroscopy (FTIR), differential thermal analysis (DTA), thermogravimetric (TG) and derivative thermogravimetry (DTG) analyses. To improve the bioactivity and control the degradation rate of Mg alloy scaffolds, the porous surface of the Mg scaffold was coated with 45S5 BG nanomaterials using the electrophoretic deposition (EPD) method. The in vitro degradation test was then performed using simulated body fluid (SBF) for 48 h. The in vitro degradation test results showed that the mass loss percentages of both samples approached each other after 12 h. The uncoated sample lost more mass than the coated sample after 24 and 48 h. The results showed that the coated scaffolds had better bioactivity and greater resistance to degradation.