Ceramics-Silikáty 53 (4) 310-314 (2009)

Design for a filler of an intervertebral cage for spine treatment on the basis of fibers and particulate composites

K. Balík, T. Suchý, Z. Sucharda, Š. Rýglová, F. Denk

Composite materials have been developed for applications in the form of an intervertebral cage (for use in spine treatment). The intervertebral cage is composed of a bearing cage made of PEEK and a composite core with the surface contacting the bone surface and ensuring elastic linkage of two vertebral bodies, resulting in good adhesion to the bone. Mechanical analysis of four different kinds of composites (particulate composites with polysiloxane matrix and/or hydroxyapatite (HA)/tri-calcium phosphate (TCP) nano particles, fabric composites based on polysiloxane matrix and polyamide fibers, and fabric composites with matrix modified by addition of HA nano particles) was performed. The changes in the mechanical properties of fiber composites with the matrix modified by nano hydroxyapatite and the effect of HA and TCP nanofiller volume fractions on the mechanical properties of particulate composites were investigated. For particulate composites, the differences between HA and TCP additives appear only in the case of compression strength. This fact is probably caused by different character of adhesion on the interface between the particulate reinforcement and the matrix. Particulate composites showed mechanical properties similar to a trabecular bone. In the case of fabric composites, a 15 vol.% addition of HA nanoparticles has a favourable effect on both modulus and strength which reach values nearly comparable with a cortical bone.

Keywords: Aramid Fibers, Polymer-Matrix Composites, Mechanical Properties, Hydroxyapatite