All these factors are interdependent.
Consequently, dry skin should be characterized by its rough appearance, without referring to its hydration level (13).
Recent research have actually questioned some established ideas notably the influence of the inflammatory process or of the content in calcium ions of the epithelial cells in skin drying. In fact, experimental results have shown that the supply of nonsteroidal anti-inflammatory agents (14) or of calcic regulators (15) did not significantly modify the skin’s state. On the other hand, the use of specific inhibitors of tryptic proteases, and particularly of “plasminogen activation system,” showed a capacity for restoring the normal state of the skin and for simultaneously suppressing all the changes related to skin drying, notably against the mechanisms of cell regulation and differentiation, of increase in transepidermal water loss (TEWL) of the horny layer, of acceleration of its renewal, and the epidermal thickness resulting from it (16).