A implantable prosthesis having an external surface at least a portion of which is an open-cell structure is made by providing an implantable member having a surface applying a first layer of elastomer to the surface, applying a first layer of particles to the first layer of elastomer, applying a second layer of elastomer to the first layer of particles, applying a second layer of particles to the second layer of elastomer, curing the layers of elastomer, and removing the particles to form an external surface at least a portion of which is an open- cell structure.
