Asymmetrically porous PLGA/Pluronic F127 membrane for effective guided bone regeneration

Porous guided bone regeneration (GBR) membranes with selective permeability, hydrophilicity and adhesiveness to bone were prepared with PLGA and Pluronic F127 using an immersion precipitation method. The porous PLGA/Pluronic F127 membranes were fabricated by immersing the PLGA/Pluronic F127 mixture solution (in tetraglycol) in a mold into water. The PLGA/Pluronic F127 mixture was precipitated in water by the diffusion of water into PLGA/Pluronic F127 mixture solution. It was observed that the membrane has an asymmetric column-shape porous structure. The top surface of the membrane (water contact side) had nano-size pores (approx. 50 nm) which can effectively prevent from fibrous connective tissue invasion but permeate nutrients, while the bottom surface (mold contact size) had micro-size pores (approx. 40 mu m) which can improve adhesiveness with bone. From the investigations of mechanical property, water absorbability, model nutrient permeability and preliminary in vivo bone regeneration, the hydrophilized porous PLGA/F127 (5 wt%) membrane seems to be a good candidate as a GBR membrane for the effective permeation of nutrients and osteoconductivity, as well as good mechanical strength to maintain a secluded space for bone regeneration.