Ageing presents threats such as osteoporosis, osteoarthritis, bone cancer and other diseases. It is estimated that 2.2 million bone grafting procedures are performed annually around the world, and the numbers continue to increase as lifestyles change and people live longer.
Presently, finding biomimetic materials (the structure and function of biological systems), which are similar to bone in terms of strength, flexibility and density, is an ongoing concern for medical scientists. The hope is that it might be possible supplement metal alloy implants using such materials.
Indeed, what has been discovered is that the structure of some woods at the microscopic level is very close to that of natural bone. Furthermore, the structure shares biomechanical properties such as high strength and lightness, due to its hierarchical organisation.
A case study on the implications of new technology was recently carried out by Professor Ugo Finardi (CNR Institute for Economic Research on Firms and Growth (CERIS), and University of Torino) and Professor Simone Sprio (CNR Institute of Science and Technology for Ceramics (ISTEC)). The Research Group on Biomaterials of ISTEC has developed this and taken inspiration from nature using a nanotechnological approach to transform rattan wood into hierarchically organised implants. The Professors, with their team of researchers, Anna Tampieri, Simone Sprio and Andrea Ruffini, found that biomimetic materials have a strength and flexibility similar to natural bone, something that cannot be achieved with current metal alloy technologies.
The professors believe that the technology could exploit the hierarchical physical structure of rattan wood to render it useful as a scaffold, thus creating a synthetic material to replace damaged and lost bone. An additional benefit is that such a material could be load-bearing, a factor that has precluded the use of earlier biomimetic materials.
However, the processing of raw wood to remove chemical components, which are incompatible with implants for humans, is long and complex. But the professors believe the benefits of producing a material, which is similar to bone, far outweigh such issues.
The process of turning wood into implants involves heat treatment of the wood to remove cellulose, lignin and other plant materials. This leaves behind a carbon skeleton that can be infiltrated and reacted with calcium, oxygen and phosphate to make a porous material, which in turn can chemically and mechanically mimic bone.
In concluding, the research team say that unlike metal alloys, ceramics and even donor bone, their patented material is low cost, has very good biomechanics and is biocompatible. It can also be integrated into existing bone, thus properly assisting bone regeneration.