A new bioprosthesis: impermeable for bacteria, permeable for fluids, incorporable by connective tissue.

Polyurethane non woven membranes with microporous inner layer and macroporous outer layer where tested bacteriologically and histologically. It was proved that the macroporous layer is suitable for the ingrowth and maturing of connective tissue, while the microporous structure prevents the invasion of bacteria, nevertheless being permeable for nutrient substances. So the material could be yield favourable presupposition to achieve bioincorporation in contaminated borderlines.