The epidermis is very important to an esthetician. An esthetician is only licensed to treat the five most outer layers of the skin, which make up the epidermis. An esthetician’s skin treatments stop where the blood starts to flow within the skin. Anything beyond the epidermis starting with the dermis layer, onto the subcutaneous layer of skin and beyond legally must be treated by a medical professional.
The epidermis is the protective layer that covers the entire body. The epidermis helps to protect the body from toxins, bacteria and loss of fluids. The epidermis is thinner than a tissue and thickens whenever the skin is hydrated.
Ever wondered what the five layers of the epidermis were? The easiest way to visualize the outermost, top five layers of the skin is to imagine that the cell is going on a trip. The trip the cell goes on is called cell turnover. The journey takes the cell an average of 28 days to make it through the five layers of the epidermis. Starting at the bottom of the epidermis, the cell’s journey begins in the Stratum Germinitivum with the birth of the cell. This layer of skin is closest to the dermis. This is where Parent Cells live. Parent Cells make an exact replica of themselves called Daughter Cells.
Melanocytes also live in the Stratum Germinitivum. Melanocytes are specialized cells that give your skin pigment and color, otherwise known as Melanin. Melanin protects the Parent Cells from damage. For every one Melanocyte, there are 37 Parent Cells that it has to protect. UV exposure triggers the Melanocyte to produce more Melanin. An overproduction of Melanin is what leads to hyperpigmentation on the skin.
On the second leg of the cell’s journey, the Daughter Cells then travel up to the Stratum Spinosium. In this layer of the skin, the Daughter Cells grow hair on the outside called Desmosomes. The Daughter Cells also get fattened up with Keratin and start losing a little moisture, showing the first signs of dehydration.
Langerhan Cells also live in the Stratum Spinosium. These specialized cells are part of the immune system and act as a line of defense. Think of the Langerhan Cell as “Larry” the bouncer. Larry roams around the Stratum Spinosium looking for anything trying to get through that shouldn’t be there, such as bacteria and disease. If Larry finds any of these invaders, he eats them up.
The next stop on the cell’s journey is the Stratum Granulosum. In this layer of the skin, the cell’s nucleus starts to break down. This is the part of the journey when the cell realizes that death is looming. The cell continues to get even fatter as its filled with more Keratin.
Within the cell, the buildup of moisture, oil and minerals encapsulate and form Lamellar Bodies. The Lamellar Bodies are then pushed towards the cell’s membrane, along the edge of the inside of the cell. The cell eventually excretes the Lamellar Bodies through it’s membrane. Once the Lamellar Bodies are released from the cells, they burst. The contents of the Lamellar Bodies are then pushed up through the Stratum Lucidum and right towards the Stratum Corneum.
The next layer of skin, the Stratum Lucidum is an optional stop for the cell on its journey. This transparent layer is packed tight with very dense cells. The reason why this stop is optional for the cell is because this layer of skin only exists if there are areas of trauma or friction on the skin. Area of trauma or friction on the skin usually result in the form of a blister on a heel, blister on a hand, corn, callus, acne or milia.
The final stop in the cell’s journey is in the Stratum Corneum. This is the layer of the epidermis where cells come to die. The Stratum Corneum is made up of dead skin cells. Itss about fourteen layers thick of proteins and Keratin. As these dead skin cells are sloughed off with regular physical and chemical exfoliation, they are continuously replaced with dead skin cells that have migrated their way to the top from the Stratum Germinitivum.
On top of the Stratum Corneum is the Acid Mantle. The Acid Mantle is a chemical protective barrier that sits on top of the outermost layer of the epidermis and acts as a second line of defense against bacteria and disease. Its made up of oil and sweat from the dermis. The Acid Mantle is at its strongest when its pH is between 4.5 and 6.5. When the Acid Mantle is acidic, it can chemically fight off bacteria and foreign invaders successfully.
It’s important to know the five layers of the epidermis. A basic understanding of the skin will help you make more educated choices in the products you use on your own skin, for the specific skin conditions you want to treat.
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