In rats and guinea pigs, transcutaneous through and through mattress sutures of different materials (silk, nylon and Prolene [polypropylene]) were tied under tension to plicate the abdominal wall or the scrotal wall. Knots were either buried subcutaneously or left outside. Monofilament sutures, with buried knots, cut through and became completely incorporated as the plicated normal tissue flattened out to a normal appearance in about three weeks. Silk sutures and bulky outside knots left suppurating sinuses. Histologic examination at seven weeks confirmed the incorporated nylon or Prolene mattress sutures were surrounded by a sheath of clean scar tissue trailing as a curtain back to the cut through skin. It is concluded that sutures of monofilament nylon or Prolene, with buried knots, can be tied under tension to include outside skin and will cut through cleanly to become incorporated without sinus or suppuration. Such incorporated sutures and their trailing curtains of clean scar tissue can provide an internal buttress against soft tissue displacement with potential clinical application.