the present invention relates to a hydrated , biocompatible tissue - augmentation compound and its methodology for implantation into mammalian tissue . the tissue - augmentation compound is comprised of : living tissue , body derived fluids , at least one nco - terminated hydrophilic urethane prepolymer derived from an organic polyisocyanate , and oxyethylene - based diols or polyols comprised essentially all of hydroxyl groups capped with polyisocyanate