Xenogeneic acellular dermal matrix as a dermal substitute in rats

Acellular dermal matrix (ADM) has been used as a dermal substitute for the treatment of deep burns, but the availability of cadaver skin for the produ ction of ADM is limited. The usefulness of porcine ADM as a xenogeneic derm al substitute in rats was studied. With the use of Dispase II (Boehringer M annheim, Indianapolis, Ind) and Triton X-100 (US Biochemicals, Cleveland, O hio), xenogeneic ADM was prepared from commercially available, cryopreserve d porcine skin, and allogeneic ADM from the rats was also prepared. Four fu ll-thickness injuries 225 mm(2) in size were created on the dorsum of each rat. One of these wounds was treated with xenogeneic ADM, and 1 was treated with allogeneic ADM, and immediately a 0.005-in thick split-thickness skin graft was placed over the ADM. The other 2 wounds were covered with 0.005- or 0.017-in thick split-thickness skin grafts alone. The wounds were evalu ated macro- and microscopically 10, 14, 20, and 30 days after grafting. At 30 days after grafting, contraction of the wounds that contained xenogeneic ADM was significantly greater than that of the wounds that contained allog eneic ADM. Craft take was poor in the wounds that contained xenogeneic ADM at 14 days after surgery and moderately good in those that contained alloge neic ADM. The use of thick autografts resulted in the best wound healing, w hereas the use of thin autografts resulted in considerable wound contractio n. Allogeneic ADM diminished this contraction, but wound healing was signif icantly worsened when xenogeneic ADM was used.