The influence of carbon fibres on the resorption time and mechanical properties of the lactide-glycolide co-polymer.

In this study the influence of short carbon fibres (CF) on mechanical properties and degradation time of the lactide-glycolide co-polymer (PGLA) and on the mechanism of bone ingrowth into the implants was determined. Mechanical properties and push-out tests were measured. The pH of solutions and the implants' weights were tested after incubation in Ringer fluid. Analysis was based upon FT-IR and SEM with EDS studies. Pathological examinations were also performed. The in vitro examination revealed that carbon fibres accelerated polymer degradation process and increased the mechanical strength of polymer. In the case of PGLA + CF under in vivo conditions, initially, the superficial polymer degradation with new tissue in-growth was observed. Next, the degradation process included also the inner part of the implant, while the bone began to grow on exposed carbon fibres. In the case of pure PGLA the growth of soft tissue can be observed at the bone-implant interface and in the implant area. Our research indicates that PGLA + CF composite can be used in bone surgery as a short-term multifunctional load-bearing implant, which initially provides a mechanical support. During the time of controlled resorption of PGLA, carbon fibres act as a scaffold for the bone growth.