>>procedures >> The Skin

The Skin

The skin is the largest organ in the body.

Functions:

Regulates body temperature through sweat glands.
Prevents dehydration.
Feel many sensations (pain, heat, cold).
Pigment protects us from the sun`s rays.
Involved in vit. D production.

Comprised of 2 layers;

Epidermis.
Outer layer responsible for the skin`s colour, texture and overall appearance.
Helps the skin stay moisturised by retaining water and acting as a barrier from
the sun.
The epidermis is impermeable to water.
The outer layer is flattened dermal cells that have migrated to the top from the
deeper dermis layer.
The migration takes 15 to 30 days in young and healthy adults. As we age the
process slows down.

Dermis.
Where all the important collagen and elastin fibres are found.
70 % of the dermis is collagen.
The rest is elastin, blood vessels, sebaceous glands, sweat glands and
hair follicles.
Collagen is the skin`s mattress.
Elastin is the coils that hold it together.

Collagen.

Abundant in early childhood.
Collagen production

. slows down in puberty
. levels off in 20`s and 30`s.
. stops in later years

Collagen helps to heal wounds and scars.
Degeneration of collagen through sun exposure and other environmental
conditions lead to wrinkles and sagging skin.
The vit. A derivative, Tretinoin, may have a positive effect on collagen.

Elastin.

The stretchy fibres that allows the skin to snap back into place.
Over time and repeated sun exposure causes elastin to break down into small
fragments.
No remedy exists for the destruction of elastin.
“ When it`s gone, it`s gone ”.

Melanocytes.

Found in the epidermis, these cells produce the pigment, melanin.
Melanin absorbs the harmful U.V. light from the sun and protects the skin`s
DNA from radiation damage.
This pigment producing cell also produces a tan which sounds desirable until
you realise that a tan is simply the body`s response to injury from U.V.
radiation.

Changes taking place in sun damage;

Stratum corneum (outer layer) is cracked.
Epidermis doubles in thickness.
Melanocytes enlarge and migrate.
Skin thickens.