The healing of hamster oral mucosal wounds covered by porcine grafts. A histologic study.

The purpose of this study was to ascertain whether porcine skin grafts are incorporated by the host or act as temporary dressings which are sloughed and to determine the host reaction in terms of inflammatory response. A split-thickness 5-mm square recipient bed was prepared in the cheek pouches of 20 hamsters. Previously frozen, irradiated porcine skin was sutured onto each bed. Animals were killed at 3, 7, 10, 14 and 28 days. Results indicated that at 3 days the graft showed signs of necrosis and host epithelium was migrating under it. Some acute inflammation was evident. By 7 days all 7 grafts had sloughed and epithelialization was complete. The graft bed was maturing collagenous tissue with a mild infiltrate of chronic inflammatory cells. At 10 days healing was almost complete. In all instances the graft appeared to have been sloughed between the 3rd and 7th day and there was no evidence of a massive inflammatory response, foreign body reaction, host incorporation or graft vascularization. These results suggest that porcine skin could be used as a "biologic dressing" in periodontal mucogingival surgery involving grafting.