Synthesis and Extraction of Hydroxyapatite Grafts from Animal Sources

Abstract

Bone is the second mainly implanted tissue after blood in the human body system. The biomechanical properties of bone result from its complex structural arrangement of organic (20- 30%) (Collagen, Noncollagenous Proteins and Lipids), inorganic components (60-70%) and 5% water [1]. Bone inorganic matrix is mainly composed of hydroxyapatite (HA; Ca10 (PO4)6(OH)2) with 3% to 8% of carbonate content [2]. Mechanical properties of the bone are characterized by Hydroxyapatite (HA) compositions, its crystalline structure, morphology, particle size and orientation. Graft materials used for formation of bone tissue include autologous bone, allogenic bone, xenograft tissue and artificial bone. Although hydroxyapatite has been used for many years as a non- absorbable biocompatible bone substitute, more recently the focus has been on the development of absorbable bone substitutes. When the area of a bone defect is filled with hydroxyapatite, the cycle of bone resorption by osteoclasts and bone formation by osteoblasts resumes at the bone surface, leading to the formation of new autologous bone.