Carbon materials in the treatment of soft and hard tissue injuries

Carbon-based implant materials are of interest because they are well accepted by the biological environment. Carbon fibrous materials developed in the Department of Special Ceramics of the University of Mining and Metallurgy in Cracow were tested in in vivo studies to determine their influence on the living body. For comparative purposes, different carbon fibers were prepared and subjected to different surface modifications. Carbon materials prepared in the form of braids were implanted in subcutaneous tissue of rabbits and into skeletal muscle of rats. Carbon fabrics were examined as scaffolds in reconstruction of bone defects. The present study examined the synthesis-structure-property relationships of fibrous carbon samples with respect to the tissue response. It was shown that the tissue response depends on the form of the material form, the degree of order of the crystallites, the surface state and microstructural parameters. Carbon fibers with higher crystallinity and a better-organized graphite structure were assimilated by the body with more difficulty and small particles coming from these materials were found in the regional lymph nodes. Low-carbonized carbon fibers (small crystallite size) underwent partial fragmentation and reacted with the biological environment by being gradually resorbed in the implantation site. The presence of acidic groups on the surface of the carbon fibers enhanced phagocytosis of the carbon material by macrophages. Depending on the surface state of carbon fibers different rates of bone wound healing were observed.