In vitro and in vivo analysis of the biodegradable behavior of a magnesium alloy for biomedical applications

The present study was designed to investigate the biodegradation behavior of Mg alloy plates in the maxillofacial region. For in vitro analysis, the plates were immersed in saline solution and simulated body fluid. For in vivo, the plates were implanted into the tibia, head, back, abdominal cavity, and femur and assessed at 1, 2, and 4 weeks after implantation. After implantation, the plate volumes and the formed insoluble salt were measured via micro-computed tomography. SEM/EDX analysis of the insoluble salt and histological analysis of the surrounding tissues were performed. The volume loss of plates in the in vitro groups was higher than that in the in vivo groups. The volume loss was fastest in the abdomen, followed by the head, back, tibia, and femur. There were no statistically significant differences in the insoluble salt volume of the all implanted sites. The corrosion of the Mg alloy will be affected to the surrounding tissue responses. The material for the plate should be selected based on the characteristic that Mg alloys are decomposed relatively easily in the maxillofacial region.