Animal-bone derived hydroxyapatite in biomedical applications

Abstract The use of animal bone-derived bone for producing bone grafting and other types of materials with biomedical applications has been a fundamental part of biomaterials science since the 1950s, when Kiel bone was first developed and used. Those early experiences paved the way for the large volume of materials and clinical research that were to follow involving animal bone-derived bone. This chapter deals with the (vertebral) species of animal bone sourced for biomedical materials that was and still is principally bovine bone but that has, in recent times, branched out to include equine, porcine, cervine, ovine, fish, ostrich, and duck-head-sourced bone. The rationales for using animal-derived bone are explored and then the processing, characterization, and dependence of the ultimate phase of hydroxyapatite obtained on the process used to extract it from bone sources are discussed. The scare in Europe and other countries from the emergence of transmissible spongiform encephalopathies in cattle herds approximately 20 years ago and the link to variant Creutzfeldt–Jakob disease (v-CJD) in humans have impelled the need (as dictated by regulatory requirements, notably in Europe) to process animal-origin products, particularly bovine bone using methods that eliminate the possibility of transmission to humans of v-CJD from use of bovine-derived implants. These methods are discussed along with a brief word on the European Commission regulations that make it mandatory for manufacturers of such products to ensure their safety when used in vivo. Finally, the chapter will close with descriptions of some commercially supplied animal bone-derived bone graft materials available on the current market and the surgical studies that have used them. In addition, a selection of other clinical studies involving noncommercially sourced animal bone-derived biomedical materials will be covered. In general, the chapter will serve to show the fundamental reach of these products in the field of biomaterials science and practice.