Influences of age, ethnic group, and skin sites on a provisory skin marking, experimentally induced, in vivo.

BACKGROUND: To study capacity of skin to being imprinted by a marking head rapidly applied (10 seconds) onto the skin under a standardized pressure (15 kPa).

MATERIAL AND METHODS: Referential photographs of skin markings, resulting from different times of application serve at grading the extent of skin imprints. The imprinting tool, equipped with 5 linear bulbs of different sizes but same thickness (1 mm), was applied onto the cheeks of 641 women of different ages (18-80 years) of 3 different ethnic groups. In the cohort of 198 Caucasian women, the marking head was pressed onto 3 different sites (outer arm, cheek, and dorsal forearm) and the kinetics of skin recovery from cheek marking was recorded on a smaller and younger part of this Caucasian cohort, ie, 141 Caucasian women, aged 18-59 years.

RESULTS: The recorded intensities of skin markings were found highly correlated with age in all 3 studied ethnic groups (Chinese, African-American, and Caucasian). Caucasian women seem more sensitive to the marking and the kinetics of recovery from such imprint was found highly dependent from its intensity, ie, the higher the grades, the slower the recovery. In Caucasian women, intensities were different between skin sites, where arm showed higher resistance to marking. Possible impact of photo-aging on the decreased skin resistance to such provoked deformation is likely of minor amplitude, as compared to the one induced by chronological aging.

CONCLUSION: This method offers a new vision on skin aging, in its variable response to a standard deformation that appears mostly driven by chronological aging.