Self-Organized Hydroxyapatite Construct for Biomedical Applications: From Pack Cementation to Structure and Mechanical Characterization.

This work presents the bioprocessing and robust characterization of the physical and mechanical properties of hydroxyapatite (HA) synthesized from two bio-precursors: bovine and catfish bones. The precursors are deproteinized by carbonization and calcination, then sintered using conventional heat treatment to form HA microparticles. Pulverization and the sol-gel process are performed to achieve homogeneity of well-packed cementitious powder constructs of controlled percentage weight compositions of HA from each precursor. The structural and compositional qualities, fracture mechanics, and mechanical properties of the synthesized powder and cementitious construct are assessed via X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and mechanical testing. The specimen composed of an equal percentage weight of HA from bovine and catfish (B50/C50) exhibited the highest fracture toughness and highest compressive strength. The highest hardness and brittleness index values are measured in the B25/C75 specimen. Under dynamic loading, the B100/C0 specimen exhibited the highest resistance to wear. The X-ray diffraction patterns revealed that the B75/C25 specimen has the highest fraction of crystallinity. The implications of these findings are discussed for the potential biomedical applications of HA in dentistry and orthopedic medicine.