Metal fiber network materials for magnetically-induced bioactivation

In this chapter, a brief outline is given of the potential of ferromagnetic fiber networks for usage in delivering in vivo strains to in-growing bone. Beneficial effects on bone-implant bonding can accrue from ferromagnetic fiber networks which deform in vivo via an external magnetic field of clinical magnitude applying therapeutic strains to bone filling the inter-fiber spaces. Simple analytical models based on the torque exerted on a fully-magnetized fiber in conjunction with tomographic data can be used to predict the magneto-mechanical response. In vitro cell culture data have been obtained on both 2D (fully-dense) and 3D (high porous) surfaces to identify an optimum fiber material and establish the surfaces’ ability to support the culture of human osteoblasts and mesenchymal stem cells without inducing toxic or inflammatory responses. Preliminary experimental results on magnetic actuation of ferromagnetic fiber networks suggest an actuation-mediated upregulation of specific genes in the osteogenic lineage together with an increase in protein release