Efficacy of in-house nanosilver polyurethane hydrogel dressing on second-degree burn wounds in a porcine model

The aim of this study was to investigate the effects of hydrogel containing nanosilver particles on a second-degree burn wound in a porcine model. The second degree burn wound was performed using 1 cm in diameter, on 100 °C heated cylindrical brass bar applied to the dorsum of pig skin. Burn wounds were randomly divided into three groups of wound dressings (WDs) including commercial polyurethane hydrogel (Cutinova Hydro®, Gr. A), in-house hydrogel (Gr. B) and in-house nanosilver hydrogel (Gr. C). The wound contraction rate and hyperemic zone were measured and investigated at 3, 7, 14 and 21 days after dressing. Biopsies were performed at day 21 after dressing and routine histological processes were performed. For the wound contraction rate, Gr. C showed significantly higher than Gr. A and B on day 7 and 14. The size average of the hyperemic zone in Gr. C on day 7 tended to be lower than other groups. For histological evaluation, the size of the granulation tissue area, number of white blood cells and neovascularization were investigated. The results showed no significant difference among groups of any histological parameters. Nevertheless, Gr. C had an average granulation area and the infiltration of inflammatory cells was greater than the other groups. In summary, all of three types of WDs used in this study could promote the recovery of secondary degree burn wounds in the porcine model. In addition, hydrogel containing silver nanoparticles represented greater healing abilities than in-house polyurethane hydrogels or commercial poly-urethane hydrogels.