The invention relates to resorbable crosslinked form stable membrane which comprises a composite layer of collagen material and inorganic ceramic particles containing 1.5 to 3.5 weight parts of inorganic ceramic for 1 weight part of collagen material, sandwiched between two layers of elastic pretensed collagen material (collagen material that has been stretched such as to be in the linear/elastic region of the stress-strain curve), the collagen material comprising 50-100% (w/w) collagen and 0-50% (w/w) elastin, and has shape and dimensions suitable for use in human tissue regeneration outside the oral cavity in rhinoplasty, postlateral spinal fusion or orbital reconstruction.