Direct comparison of skin physiology in children and adults with bioengineering methods

The aim of the study was to investigate whether the physiologic skin parame ters of transepidermal water loss (TEWL), stratum corneum hydration (capaci tance and conductance), dynamic stratum corneum hydration parameters (hygro scopicity and water-holding capacity), skin color (a* and L* axes; chromame ter), cutaneous blood perfusion [laser Doppler flowmetry (LDF)], and pH val ue differ between a sample of 44 children [C] (average age 3.5 years) and a directly comparable sample of 44 adults (their parents) [P] (average age 3 4.6 years). The results can be described as follows: TEWL C: 6.2 g/m(2)/h, P: 5.4 g/m(2)/h; stratum corneum hydration, capacitance C: 75.4 AU, P: 76.1 AU; conductance C: 27.1 muS, P: 19.2 muS; hygroscopicity C: 129.0 AU, P: 1 32.7 AU; water-holding capacity: C: 127.7 AU, P: 127.6 AU; redness (a*) C: 7.31, P: 8.21; lightness (L*) C: 67.63, P: 66.36; LDF (%) C: 24.6, P: 18.7; pH value C: 4.91, P: 5.07. In comparison to the skin of the adult sample w e investigated (the parents of the 44 children), the skin of the small chil d can be characterized in the following way: it has a significantly lower h ygroscopicity, a lighter (higher L* values) and less red color (lower a* va lues), and an increased cutaneous blood perfusion (LDF).