Variations of the histomorphological characteristics of human skin of different body regions in subjects of different age.

The aim of this paper was to create a reference model for the qualitative and quantitative characteristics of healthy human skin in different body regions and different life periods. For this purpose we have taken skin biopsy specimens from 15 different body regions: capillitium, forehead, cheeks, anterior neck, thorax, axilla, abdomen, back, gluteus, anterior arm, anterior forearm, palm, anterior leg, anterior lower leg and sole. The biopsies were histologically elaborated according to a standard paraffin technique, and the obtained histological slides were qualitatively and quantitatively analysed with the use of a computer system for image processing and analysis (Lucia M, Version 3, System for Image Processing and Analysis). The examinees were divided by age into five groups: from full-term infants up to the age of 1 year; from the age of 2 up to the age of 12 years; from the age of 13 up to the age of 22; from the age of 23 up to the age of 55; from the age of 56 up to the age of 73. In each exemplar were determined: the total skin thickness in each region at each age group, total thickness of the epidermis, total thickness of the corium, thickness of the papillary and reticular layers of the corium. In this period the thickening is about 4-4.5 times. The growth of the thickness comes as a result of the growth of the thickness of the reticular corium, values of which grow by 4-5 times. The height of the epidermis in newborns shows higher values than the second group (childhood). In the third and fourth group the values of the epidermis are from 1.5 to 2.5 times higher on those parts of the body which are uncovered and exposed to externalities. The essence of the changes that happen to the skin is structural final formation, which is turbulent and targeted in youth (in order to harmonize structural and functional abilities of the human organism) and in mature age to synchronize the function of the skin with the other systems of the organism.