A comparative study on the characteristics of sintered hydroxyapatite derived from bovine bone powder, synthetic hydroxyapatite, and bovine hydroxyapatite

This study presented a comparative analysis of the properties of the hydroxyapatite derived from bovine bone powder (BP), synthetic hydroxyapatite (SHA), and bovine hydroxyapatite (BHA). The sintered samples were characterized using X-ray diffraction (XRD), scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDS), and Vickers microhardness measurements. XRD results confirmed that the dominant phase in all sintered samples was hydroxyapatite with enhanced crystallinity. The sintered SHA showed the best performance compared to the BHA and BP samples, as indicated by the highest crystallinity (84.10%), hardness (2.404 GPa), and relative density (92.30%). Additionally, the sintered BHA exhibited the lowest linear shrinkage, followed by SHA and BP, indicating the best thermal stability. The SEM observations revealed dense and uniform microstructures in the SHA sample, while BHA displayed compact grains with fine microporosity beneficial for bioactivity. Overall, the findings indicate that SHA possesses superior mechanical performance and is suitable for structural implant applications. BHA also offers favorable bioactivity and compositional similarity to natural bone, making it more appropriate for biofunctional coatings and bone graft substitutes.