Dandruff and pitiriasis are the same thing which is the first point that must be made clear. The skin naturally and gradually regenerates from the inside out and then naturally flakes - dead corneous skin cells - renewing itself. We are speaking about a normal process of cell regeneration. Excessive flaking produces pitiriasis or dandruff. Pitiriasis steatoide or greasy dandruff is when we see flakes adhering to the scalp.

Grease has flattened the flakes and sometimes formed crusts.

Seborrhoea
Grease, secretions from the sebaceous glands, constitutes the largest part of what we call the peripheral lipid film, the protective oily film of our skin which protects us from external pathogenic agents. When the sebaceous gland produces an excess this is seborrhoea.

Alopecia

Alopecia can be caused by internal or external factors.

Although there are various types of alopecia there are three main groups which are: AREATE, DIFUSE AND ANDROGENETIC

AREATE or bald plates, is a common enough form of hair loss. They are normally caused by nervous factors (stress, depressions, anxiety, etc.), and in a smaller degree by viral processes, mouth infections which can be infections of the mucous membrane or caries, and by thyroid problems.

DIFFUSE, is a type of hair loss which is difficult to detect in a short space of time, we could say that the quantity of hair which is lost is greater than quantity of hair regrowth or that regrowth is less than loss. In any case, when it is detected, is when the hair loss is more than evident.

ANDROGENETIC, alopecia which effects approximately 85% men.

The combination of a hormone (testosterone T), with the enzyme (5alfareductasa), gives rise to the hormone (DHT) which is very damaging to the hair producing an inflammation of the sebaceous glands and a progressive shrinking of the follicle with atrophy in the papilla in each growth cycle ending in the inevitable scaring of the hair follicle completely preventing capillary regeneration.

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