Hydroxyapatite (HAp) is a naturally occurring mineral form of calcium apatite that closely resembles the composition of human bone and teeth. With the chemical formula Ca₁₀(PO₄)₆(OH)₂, hydroxyapatite has become one of the most important biomaterials in the fields of orthopedics, dentistry, and tissue engineering. Its biocompatibility, bioactivity, and ability to bond directly with bone make it...