Ethnic skin types are known to differ in their morphological and physiological features. Thus, treatment responses may vary among different races. We aimed to assess skin morphology of different ethnicities and to compare the effect of short-term moisturizer application using optical coherence tomography (OCT) and reflectance confocal microscopy (RCM). Thirty healthy female subjects of European, Asian and Black ethnicity at 30-45 years of age were included in the study. OCT and RCM imaging was performed on the cheek to compare morphology. Following 2-weeks application of a moisturizer cream (Sebamed® Lotion) on one forearm, imaging was performed on both forearms to assess and compare treatment responses.  Epidermal thickness and morphology of pores varied between the three ethnic groups, with Black subjects displaying the thickest epidermis and largest skin pores. On the treated forearm, a significant increase in the epidermal thickness was measured in all groups by OCT as compared to the untreated arm.  A significant decrease in the width of skin folds after treatment was detected by RCM in all ethnic groups. In conclusion, different ethnic skin types showed variations in skin morphology and treatment response to short-term moisturizer application. OCT and RCM were useful methods for non-invasive, real-time, repeated assessment of ethnic skin.

Effects of short-term moisturizer application in different ethnic skin types - non-invasive assessment with optical coherence tomography and reflectance confocal microscopy