Acne is a skin disease, in particular the pilosebaceous.
The pilosebaceous unit is a small pocket through the different layers of the skin and containing at its center a draft of hair and sebaceous glands.
The sebaceous gland produces sebum (oily substance that protects the skin from cold, sun, pollution ...), flowing through a channel on the surface of the skin.
This disease occurs in 3 steps 1:
1- The sebaceous glands pack and begin to produce too much sebum. This is the "sebaceous hypersecretion" or "seborrhea." The skin becomes oily and shiny and thickens the surface (that is hyperkeratinization).
At the same time, the cells (called keratinocytes) forming the channel through which flows the sebum, stick to each other, filling the channel and forming the microcomédon2, 3.
2- Sebum thus remains stuck in forming an open comedo ("black spot") or closed comedo ("white point") channel.
Blackheads and whiteheads are the first signs of acne.
Acne "retentive" talking.
3- Bacteria normally present on the skin, the barbarous name of Propionibacterium acnes, delighted to find food in the sebum and will multiply and cause inflammation. It is the appearance of red or white button.
Acne "inflammatory" 3.4 talking.
Some buttons do not heal properly and leave scars.
There are several types of scars. The most common are represented by holes, sometimes deep (so-called ice pick), or U-shaped or crater. They can be explained by the loss of too many cells and fibers after inflammation (atrophic scars).
Instead, other scars form a relief more or less rounded, and show an excessive proliferation of skin cells during wound healing. We talk about hypertrophic scars.
Some scars may remain.
Acne evolves by "pushed", that is to say that there are times when the buttons are present and others where they are no longer there.
It disappears spontaneously in most cases to 19-20 years2. However, given the discomfort it frequently and it can cause scars result, it is best not to sit croisés5 arm 6 as acne,
