Bioceramic and Composite Scaffolds in Drug Delivery and Bone Tissue Engineering
Natural bone, which provides adequate mechanical support to the human body, consists of a composite of collagen and needle-like nanocrystals of calcium phosphate. Because of their similarity with natural bone mineral, calcium phosphates have been used in dentistry and orthopedics for over 30 years and are also considered as the most appropriate candidate for bone tissue engineering. Three-dimensional scaffolds from ceramics as well as composite bioceramics are being investigated to mimic the natural bone formation and persuade the body to heal bone implants in a natural manner. Nanophase calcium phosphates can mimic the dimensions of constituent components of natural tissues and can modulate enhanced osteoblast adhesion and resorption with long-term 86functionality of tissue-engineered implants. The drug delivery approach from bioceramic scaffolds to induce the formation of functional tissues has also been studied for manipulating the microenvironment suitable for the required cell function. This chapter reviews some of the recent trends in bioceramic and composite scaffolds used in drug delivery as well as in bone tissue engineering, giving emphasis on nanophase calcium phosphates.