ABSTRACT
The field of tissue engineering (TE) represents the next generation of structures that facilitate self-healing though gradual depletion of the implanted material [1].As a specific area of emphasis utilizing this therapeutic approach, the need for bone replacement can arise from trauma, infection, cancer or musculoskeletal disease. Selected estimates note that $14 billion is spent annually in treating osteoporotic fractures in the US alone [2].For treatment, both natural and synthetic materials are used in a variety of approaches, including bone autografts (taken from another area of the skeletal system of the patient), allografts (involving a human donor source other than the recipient patient), or xenograft (processed bone
from animals). Given inherent size and pain limitations associated with autografts, and immune concerns over allografts/xenografts, a range of synthetic bone graft materials have been developed, with some in clinical use for some time [2, 3].These materials are required to have a number of particular physical and biological properties, and include: porosity (with corresponding mechanical strength, matching either that of cortical (dense) or cancellous (spongy) (bone), proper biodegradation rates, osteointegration (direct chemical bonding to the bone surface), and osteoconduction (passive growth, i.e., mineralization) [1].Yet polymeric materials often suff er from a lack of osteoinduction (active encouragement of bone growth), insufficient mechanical strength, and insulating electrical character. Addition of bioactive ceramic phases in composite form do demonstrate improved induction and mechanical strength, but yet are still insulating from a conductivity point of view and suff er from phase separation issues.
