Bioceramics: New Bones for Old

The porous structure of bone is matched by the mineral honeycomb of a bioceramic.

Living scaffolding

So how can these bioceramics provide a useful substitute for damaged bone? Dr Karin Hing, a researcher at the London-based Interdisciplinary Research Centre in Biomedical Materials explains: “They are active materials. Once implanted in the patient, they interact with the surrounding fluids, and while they are being gradually absorbed by the body, they promote bone regeneration, acting only as an initial scaffold for the new bone”.

The bioceramic provides the right environment for the new bone to grow into. They also have a special chemical composition that allows a type of cell called osteoblasts - responsible for bone production - to attach to the ceramic’s surface, and start generating new bone. The interconnected tiny holes within the bioceramic structure facilitate the proliferation of the cell network, and the growth of the bone, within the synthetic scaffold. The calcium content of the bioceramic provides the inorganic component that new bone requires to develop its mineral-like structure.

The complex processes underlying bone’s astonishing capability to regenerate are only partially understood. “Each new finding in our research throws ten new questions that need an answer, and so on” says Dr Hing. This is proving to be the major impediment to the further development of bioceramics. At the moment, they are improving only slowly, by trial and error: the researchers slightly change the properties of the material, and then study the biological response to the synthetic material.

The use of bioceramics is expected to have a large impact on the future of bone surgery procedures. In England alone, the National Health Service recorded 77,000 hip replacement operations in 2003, among 617,000 bone and joint operations. The first generation of bioceramics has already been introduced, with good initial results. The new material will eventually obviate the use of current techniques, such as titanium implants which are infection-prone, and bone harvested from another part of the body, which may also cause pain and major infection at the site where the bone was extracted.

We have already come a long way since Dr Gluck opened the first era in reconstructive bone surgery. Despite the long path ahead for Dr Hing and her co-workers in their quest to perfect their material, the second era in bone repair has already begun.

Total Joints - the early history of joint surgery
http://www.totaljoints.info/Prehistory_GluckPean.htm

Azom - the A to Z of Materials - on Bioceramics
http://www.azom.com/details.asp?ArticleID=3623