The Effects of Occlusive Dressings on Inflammation and Granulation Tissue Formation in Excised Wounds in Rats

Abstract

The effects on the healing of full-thickness excisional wounds treated with either of two occlusive dressings (Mezinc or Duoderm) were compared with the effects of gauze soaked in saline. The wounds were made on 86 rats and were examined clinically, histologically and biochemically four, eight and twelve days after wounding. Four days postoperatively the Duoderm-treated wounds differed significantly from the other two groups. Clinically, an adherent discolored gelatinous mass remained after removal of the firm part of the Duoderm dressing. Histologically it corresponded to a superficial exudate containing polymorphonuclear leukocytes (PMNs), macrophages and condensed foreign material. There was also a more extensive inflammatory reaction in the underlying tissues compared with gauze or Mezinc treatment and debris was seen in vesicles extracellularly and in foamy macrophages. Foamy macrophages were only seen in the Duoderm-treated wounds. These macrophages were mainly confined to the granulation tissue, which was about twice as thick as in the other two treatment groups twelve days after excision.

Key Words:

• wound healing
• wound treatment
• zinc