Developing in vitro assays to quantitatively evaluate the interactions of dressings with wounds.

Evaluating interactions between dressing and wound is important for understanding wound management. This study quantitatively compared four polyurethane foam-based wound dressings for their absorption profile, cell penetration, and adherence using two novel in vitro assays. The dressing with uniform pore sizes varying from 25 similar to 75 mu m showed the highest absorption of both culture media and serum. The same dressing showed a 1.2- to 3.6-fold lower cell adherence (3 hours) than the other dressings, and similar to 20-fold lower cell penetration (5 days) than dressings with pore sizes varying from 55 to 343 mu m. Additionally, cell and dressing interactions using a 3-dimensional wound healing assay showed that the dressings with the smallest pore size of 25 similar to 75 mu m maintained the highest cell viability (76.3%) and promoted cell migration into the wound site. This data suggest that polyurethane foam dressing with smaller and evenly distributed pores promotes wound healing with less cellular adhesion and penetration.