A highly macroporous biodegradable composite scaffold for bone tissue engineering applications.

摘要

A new composite scaffold for bone tissue engineering applications has been prepared by combining biodegradable poly(lactide-co-glycolide) (PLGA) with bioresorbable calcium phosphate cement particles (CaP) through the processes of particle fusion, particle leaching and phase separation. The scaffold is characterized by a high level of interconnected macroporosity, macropores of 0.8∼1.8 mm, porosities ranging from 81 to 91%, improved mechanical properties with respect to the polymer alone, controllable degradation rate and excellent dimensional stability during culture—with or without fibroblast-like cells. Scaffold properties were controlled by adjusting PLGA molar mass and concentration, CaP/PLGA ratio and porogen size. Testing mechanical properties in wet conditions at 37°C is more stringent than in dry conditions, but more relevant for materials to be employed in a biological milieu; the new scaffold was found to exhibit adequate mechanical properties in wet/37°C conditions and withstand the forces of cell contraction. The new composite was also osteoconductive in vivo. It was found that small (20 μm) CaP particles favored bone ingrowth into, and remodeling of, the scaffold.