Osteointegration properties of carbon fibre-reinforced plastics.

Problem: To what extent are carbon fibre-reinforced plastics (CFRP) suitabl e as an osseous integration surface for implants? Method: CFRP test implant s having a plexus-structured, rhombus-structured, and plexus-structured, hy droxyapatite surface were implanted in the femura of mini-pigs. Exposure ti me lasted 12 weeks. The implants were subjected to a macroradiological, a h istological-histomorphometrical, and a fluorescence-microscopical evaluatio n. Results: One half of the uncoated, plexus-structured implants were not o steointegrated, the other half displayed an osteointegration rate of 11.8% in the spongy area and 29.8% in the cortex layer. The HA-coated test implan ts showed an osteointegration of 29.5% in the spongiosa and 56.8% in the co rtex layer. The rhombus-structured test implants had an osteointegration of 29.2% (spongiosa) and 46.2% (cortex layer). Conclusion: Compared to the os teointegration of metallic, especially titanium surfaces the CFRP surfaces tested by us fared worse, especially the uncoated, plexus-structured surfac es. For this reason we view very critically the use of carbon-fibre reinfor ced plastics together with the surfaces tested by us as osteointegrating su rfaces.