In vivo investigation on the effects of metal oxides in hydroxyapatite biocomposite implants for improving bone regeneration

Incorporating biocompatible nanomaterials in bone implants continues to pose a signifcant challenge in biomedical engineer?ing. In addressing this issue, this study examines the critical role of the interactions of nanoscale metal oxides, specifcally Al2O3, TiO2, and SiO2, with hydroxyapatite while developing novel multiphase biocomposites. The study also investigates how animal models respond to these new implants while focusing on improving the physicochemical properties, micro?structure and osteoconductivity of calcium phosphate ceramics. Blood antioxidant enzymes and bone turnover markers were examined, and the efects on vital organs like the kidneys and liver were investigated. The results demonstrated that hydroxyapatite/SiO2/TiO2 (SHT) composite signifcantly impacted the liver and kidney functions during the study periods. However, the hydroxyapatite/SiO2/Al2O3 (SHA) composite had no measurable efect at 2 days, while there was a signifcant efect at 20 days. Overall, it is concluded that the SHT composite ceramic has more osteoconductive efects and relatively high toxicity on the liver and kidney. SHA is found to be moderately toxic, and hydroxyapatite/SiO2 (SH) composite displayed lesser or no toxicity. The results, which showed a signifcant depletion of blood GPX and SOD, indicate that oxidative stress mediates the cytotoxicity of the SHT and SHA composites.