[Skin aging and collagen].

The Aging process is a dynamic and unchangeable phenomenon which affects all systems in the body. In the skin, the old appearance is represented by wrinkles and sagging and results from structural alterations on the molecular level. Modifications in collagen, the most important protein of the connective tissue, era responsible for these anatomic changes. The investigation of the qualitative and quantitative distribution of the collagen fibrils has been very useful for understanding the structural and functional alterations that occur during the aging process. The modulation of this phenomenon will only be possible if we understand its physiopathology.