On the replacement of collagen fibers with carbon nanotubes in bone tissue:A bio-mechanical approach

Bone is one of the most dynamic tissues in our body. In order to reach an optimal structure, it undergoes continuous resorption and formation from birth to death. Artificial bone can be produced by the replacement of bone’s natural fibers, i.e. collagen fibers, with artificially made ones (such as carbon nanotubes). However, the great dependency of bone remodeling on the mechanical stimuli, besides considerable differencesbetween the mechanical properties of CNTs and those of CFs, may encourage one to hypothesize that such replacement will cause an imbalance in the rate of normal bone remodeling process. Results of this study show that the application of CNTs instead of CFs causes a significant reduction in strain energy density (SED) within the bone, which cannot be compensated even in the presence of micro-cracks (as stress amplifiers). Based on this research, it is concluded that this abnormal SED distribution in artificial bone matrix can destabilize normal bone remodeling process, and so may cause some abnormalities in both its mechanical and biological functions.

Keywords:

Bone Remodeling Process , Carbon Nanotubes , Collagen Fibers , Strain Energy Density