Abstract: A medical barrier that includes a sheet of unsintered substantially unexpanded polytetraflouroethylene (PTFE) polymer material having a density in a range of about 1.2 gm/cc to about 2.3 gm/cc, and preferably in the range of about 1.45 gm/cc to about 1.55 gm/cc, and having at least one textured surface. Preferably, the sheet has one textured surface and one substantially smooth surface, and has substantially uniform strength in all directions.