Fundamental Properties of Bioceramics and Biocomposites

Several varieties of ceramics, such as bioglass-type glasses, sintered hydroxyapatite, and glass-ceramic A-W, exhibit specific biological affinity, i.e., direct bonding to surrounding bone, when implanted in bony defects. These bone-bonding ceramics are called bioactive ceramics and are utilized as important bone substitutes in the medical field. However, there is a limitation to their clinical applications because of their inappropriate mechanical properties. Natural bone takes a kind of organic-inorganic composite, where apatite nanocrystals are precipitated on collagen fibers. Therefore, problems with the bioactive ceramics can be solved by material design based on the bioactive composites. In this chapter, an overview of fundamental properties of ceramics and biocomposite materials for biomedical application was reported.