A brief review of the medical literature shows that occlusive dressings provide effective therapeutic intervention either as an adjunct to topical medications or as a monotherapy for certain skin diseases, especially psoriasis and dermatitis. Applications also are found in verruca vulgaris and possibly other dermatologic diseases involving disruption of the stratum corneum (SC) permeability barrier or abnormal epidermal differentiation. Although the physiologic and chemical changes that occur on occluded human skin are concisely summarized, the mechanism(s) of action remain incompletely explored and their therapeutic and cosmetic potential incompletely developed.
Occlusion occurs on a regular basis from diapers and feminine hygiene products to clothes, gloves and bandages. Originally felt to be a neutral intervention, occlusion has been found to be active on the skin. This article briefly reviews medical research on the effect of occlusion on human skin, both healthy and diseased, and illustrates the current knowledge regarding occlusion as an active agent.
(A seminar on skin and wound care is described in Symposium on Skin and Wound Care.) Plastic films: Aly et al. performed five days of occlusion with vinylidene polymer plastic film on human forearm skin. During occlusion, pH increased from 4.3 pre-occlusion to 7.0 postocclusion. Transepidermal water loss (TEWL) increased from 0.56 mg/cm2/h to 1.87 mg/cm2/h and carbon dioxide emission increased from 25 nL/cm2/min to 118 nL/cm2/min. Although P values were not provided, the commentary indicated that this data was statistically significant.