The role of hydrogels in the development of artificial bone substitutes

Biomedical hydrogels for tissue engineering and more specifically for bone regeneration purposes are investigated throughout this book chapter. The most commonly utilised natural and synthetic polymer materials researched in the development of such scaffolds is initially documented. Synthesis techniques and in particular the role of photopolymerisation in the design of these devices is also explored. The importance of the physical and mechanical performance of the hydrogel scaffolds is examined, while current mechanisms of improving mechanical performance including the use of composite materials are considered. The importance of porosity, scaffold surface modification, degradability and degradation rate is also highlighted. Biological considerations in terms of preliminary toxicological analysis, cell isolation and loading, growth factor incorporation and release, as well as other advanced clinical requirements necessary for bone regeneration scaffolds are evaluated. While it is clear following critical appraisal that hydrogels alone will not suffice as load bearing bone tissue engineering devices, hydrogel composites look set to play a vital role in the development of the next generation of bone substitute materials.