Evaluating Water Permeability and Occlusion in Wound Dressings and Topical Cosmetics

By: Hongbo Zhai, MD, and Howard I. Maibach, MD, University of California

Posted: June 30, 2009, from the July 2009 issue of Cosmetics & Toiletries.

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As a reminder, the present study measuring water vapor was to determine the dressing’s permeability to water, not the actual healing process itself. These results supplement previous findings^{1-6, 15} and may prove valuable when considering future in vivo wound-related occlusion experiments. In this pilot study, the results were generated from a limited sample size; the authors suggest a validation study with larger samples.

Conclusion
The results of this study show the occlusive film yielded the least amount of water vapor while the semi-occlusive bandage allowed relatively more; the copolymer yielded about the same amount as the control. Thus, the experiment could be paired with the findings of other experiments on the effectiveness of various dressings to determine whether a particular dressing is desirable or not. Moreover, future experiments could elaborate on the unknown properties of the copolymer to possibly produce a more effective way to heal human skin wounds.

Further, in vivo studies would provide in depth details as to the correlation between the permeability of a dressing to water and possibly air. Recent review provides additional insight that wound dressings remain a standard treatment since its advantages outweigh its disadvantages.¹⁵ The authors believe that this new method may aid in the development and evaluation of more occlusive cosmetic formulations.

References
Send e-mail to zhaih@derm.ucsf.edu.
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