Skin replacements. The biotechnological quest for optimal wound closure.

Extensive skin loss from a variety of conditions is associated with significant functional morbidity and loss of life. In many patients, a limited number of donor sites available for harvesting autologous split-thickness skin grafts prevents early, effective, and permanent wound closure. In the past 25 years, significant biotechnological advancements have been made in defining the criteria and manufacturing ingredients in materials that could serve as skin replacements for permanent wound closure. The optimal skin replacement should have the functional and cosmetic properties of the dermis and the epidermis. It should provide rapid, functional wound coverage and barrier protection to microorganisms, normalize fluid flux and hypermetabolism, and provide long-term stability without contraction or hypertrophic scarring. In addition, the optimal skin replacement should be nontoxic, easily stored and used, and relatively cost-effective. This report will discuss the two major skin replacement designs available today, cultured keratinocyte grafts and bioartificial bilaminate systems, outline the advantages and disadvantages of each material, report the results of clinical trials for each, and speculate on the potential for each material to serve as a practical skin replacement.