The Degradation Behavior of Poly(α-hydroxyacid) Composite Material Containing Porcine Cortical Bone in a Phosphate-Buffered Solution

Abstract

The composite containing 10 wt% of osteoconductive porcine cortical bone (PCB) and 90 wt% of bioabsorbable poly(L-lactide) (PLLA) was manufactured. The degradation behaviors of the PLLA/PCB composite in-vitro up to 20 weeks, including water uptake, weight loss, mechanical properties, molecular weight and morphology, were investigated by soaking in phosphate-buffered solution (PBS). The results indicated that the water uptake and weight loss increased with increasing degradation time, while the mechanical properties and molecular weight decreased. There were a large number of microcracks and erosive holes on the surface and in the interior of the PLLA/PCB materials after 20 weeks. The degradation mechanism of PLLA component in the PLLA/PCB is indicative of an autocatalysis process. The degradation of PLLA complies with first-order kinetics, and the rate constant of the biodegradation process of PLLA component is 6.6 × 10−3 day−1.