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Tretinoin-iontophoresis in atrophic acne scars
J B Schmidt1, P Donath, J Hannes
1Department of Dermatology, Institute of Clinical Pathology, University of Vienna Medical School, Austria.
Background:
Atrophic acne scars are a frequent problem after acne. Hitherto, mainly invasive treatment measures were possible. In a recent paper, we demonstrated the positive effects of iontophoresis with 0.025% tretinoin gel vs. estriol 0.03%.
Objective:
In this further study, the recording of the clinical effects of iontophoresis with 0.025% tretinoin gel in atrophic acne scars was supplemented by immunohistochemistry investigations of collagen I and III, proliferation markers, and the estimation of epidermal thickness.
Methods:
The treatment was performed twice weekly in 32 volunteer patients for a period of 3 months by application of the substance under a constant direct current of 3 mA for 20 min. Skin biopsies prior to and at the end of treatment were performed in 32 voluntary patients in order to investigate collagen I/III and proliferation markers by immunohistochemistry methods.
Results:
Clinically, at the end of treatment, in 94% of patients a significant decrease in the scar depth was observed. Neither epidermal thickness nor proliferation markers revealed a significant increase at the end of treatment. Furthermore, collagen I and collagen III showed no common trend, as expressed statistically by a lack of significance. In some cases, increases in collagen III became evident at the end of treatment.
Conclusions:
Tretinoin-iontophoresis is an effective, noninvasive treatment of atrophic acne scars without causing disturbing side-effects.
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