Comparison of a sealed, polymer foam biodegradable temporizing matrix against Integra® dermal regeneration template in a porcine wound model.

The aim of this study is to develop and optimize the first stage of a proposed two-stage skin graft replacement strategy. This entails creation of a material that can be applied immediately after burn excision to "temporize" the wound bed, become integrated as a "neodermis," resist contraction and infection, and provide the grounding for the second stage (an autologous, cultured composite skin). Four 8 × 8 cm wounds were generated in six pigs to assess and compare wound contraction using Integra® dermal regeneration template, a biodegradable temporizing polymer matrix (sealed and unsealed), and a secondary intention wound. All dressings were contiguous. Infection resulted in early spontaneous delamination of the Integra® marring the long-term comparison. The wounds treated with the sealed polymer thus contracted significantly less than the wounds treated with Integra® over the 28 days. Histologically, a thick layer of scar developed superficial to the Integra®, unsealed polymer, and in the secondary intention wounds when compared with the sealed polymer, where such a scar layer was characteristically minimal. No clinical signs of infection were observed for any polymer-treated wound. Once the Integra® silicone layer delaminated, wound contraction was aggressive. Optimization of the biodegradable sealing membrane is imminent, and the second stage of composite skin development is under way.