Effect of annealing temperature on the degradation of reinforcing fibers for absorbable implants.

摘要: Calcium phosphate fibers designed for reinforcement of bioabsorbable fracture fixation devices were evaluated their properties upon annealing. The composition these 54% PO 4 , 27% Ca, 12% ZnO, 2.5% NaPO 3 and 4.5% Fe 2 O they either not annealed, annealed at 250°C, or 420°C. Chemical degradation, mass loss, morphology degradation studied. was performed in Tris-buffered HCl, while loss morphologic studies both physiologic nonphysiologic solutions. results showed that rates inversely proportional to the annealing temperature. Mass analysis immersed two solutions (calf serum simulated body fluid) revealed little change fiber diameter up 60 days. Morphologic examination until days, after which thin shells found be peeling off outer coating fiber. Samples tris-buffered HCl a dramatic difference mode among three fibers. Fibers those lower temperatures underwent delaminating type appeared destroy overall integrity fiber, whereas 420°C crater-like deterioration alignment remained intact. It is therefore concluded higher slows degradation. highest also undergo allows them maintain structural integrity. Although close glass transition temperature may produce an initially weaker chemical physical occur much slower, making most suitable biodegradable implants.