Toxicity testing of wound dressing materials in vitro

There is a bewildering array of dressing materials available for wound coverage. The choice of dressing is often by local custom or practical experience. We wished to investigate if different dressings varied in their ability to either stimulate or inhibit proliferative activity and differentiation in an in vitro test system. We have used a number of test systems for this study. Human dermal fibroblast and keratinocyte cultures were used to screen for proliferative and cytotoxic effects. A more complex "organotypic" method involving fibroblast-impregnated collagen gels overlaid with epidermal keratinocytes was used to investigate effects on differentiation. Dressings were selected from each of the major types available, from simple gauze to hydrocolloids. Of the dressings tested, some reduced cell growth rates but the majority showed no major effect on proliferation or differentiation. Of those displaying an effect, only one could be attributed to cytotoxicity.