Response to polyetherimide based composite materials implanted in muscle and in bone

The in-vivo response to a composite material obtained with polyetherimide (PEI) reinforced with carbon/glass fibers was investigated by histological methods by implanting cylinders in muscle and in bone of the New Zealand White rabbit. A common metallic alloy, widely used in orthopaedic surgery, was used as control (Stellite). The aim of the study was to analyze the biological response towards the surface of the material. Composite implants and metallic implants did not induce adverse or inflammatory reactions. The morphological picture produced was similar, in muscle and in bone, for both materials. In muscle, cylinders were confined by an extremely thin fibrous layer and the overall appearance of the muscular tissue was normal. In bone, cylinders were confined by a nearly annular rim of newly formed bone. From these data it is possible to derive that the response to PEI-based composite material is comparable with the response to metallic substrate and, then, the material can be suitable for clinical application.