The Hair System

The hair system is referred to as the pilosebaceous system. This hair system consists of the hair and its reproductive machinery, and is normally broken into four major parts:  

*Follicle - the hair canal

*Papilla - the organ of hair growth

*Sebaceous gland - the associated oil gland

*Hair - shaft or strand of dead and hardened "keratinized" structures

Follicle
All of our facial and body hair grows out of a depression or indention in the skin known as a follicle.  Think of a balloon, your fingertip pushing into its surface -- the space created by your finger is like the canal of each hair follicle. The inside of each follicle is much like the skin's surface. It's really just an invagination, or inward fold, into the skin with specialized cells for producing a hair.

The depth, size, and the angle of this inward fold varies over the skin surface.  It is dependent on the location on the face or body, by our gender and genetic background, and by biochemical factors such as hormones. The lower portion of the follicle has an expanded shape and is called the follicle bulb. Within this bulb, there is an area of actively dividing cells called the hair matrix. This is the source of hair production.The follicle and the hair it produces continues through repeated cycles of growth and rest. 

Papilla
At the base or bottom of the follicle lies a tiny structure made of dermal (related to the skin) cells called the papilla.  This tiny organ, indented into the bottom of the hair bulb, feeds the newly formed hair cells from its blood supply.  These newly formed hair cells grow and die continuously,  forming a keratinized structure -- the hair shaft.  The hair shaft continues to grow outward from the follicle base.  Other keratinized structures found in mammals include nails, horns, and hoofs. The area of the hair bulb/papilla is the main location that is targeted for destruction by permanent hair removal methods. 

Another area that is targeted during treatment is an adjacent area that contains undifferentiated cells, called stem cells. These cells maintain the follicle's life, allowing it to continue into another growth cycle if not destroyed as well.  The measure of any permanent hair removal method is a combination of properly destroying the hair bulb/papillary region and the stem cells while leaving adjacent structures no more than minimally harmed.

Sebaceous Gland
Also known as Oil glands, are located close beneath the surface of the skin over the entire body.  The purpose of these glands is to excrete wastes from the dermic system, and to prevent moisture loss through lubrication of the skin and hair. The oily material secreted is called sebum.

A large concentration of these glands are concentrated in the facial/beard area. Sebaceous glands are often attached to a follicle, the duct opening connects into the follicle near the skin's surface.   There may be more than one gland attached to a single follicle, while other follicles may have no sebaceous attachments.  

Hair
The papillary region is often referred to as the "hair root,"  The hair shaft is the portion of the hair that grows above the skin surface. The types of hair produced by the follicle are roughly broken into two categories: vellus and terminal.

Vellus Hair
This the "peach fuzz" type of hair that is normally found on a woman's cheek or a prepubescent child.  It is soft and downy, and lacks color (pigmentation). The follicles producing vellus hair are shallow, and the hair shaft produced is relatively short.  Vellus hair is normal in women and is not treated with permanent hair removal techniques.

Terminal Hair This is the deeply rooted, coarse, and often darkly colored hair that makes up the male beard.  Terminal hair begins its development as the peach fuzz type, and over time, develops greater length than its neighbors (accelerated vellus stage), and as the conversion progresses, the develops color and coarseness.  At this point, the hair is of a terminal type. 

Terminal hair grows from the scalp, eyebrows, underarms, pubic area, face, chest, abdomen,back and buttocks, back and other parts of the body. Most often terminal hair develops from normal bodily changes. Beard growth and excess body hair in males , as well as pubic and underarm hair in men and women is the result of puberty. 

There can be other reasons for terminal hair growth. These causes include disease, adverse effects from certain medications, and emotional changes. 

If you cross-section a hair, it is comprised of three layers.  The inner-most layer is called the medulla.  The middle layer which makes up the majority of the hair shaft is called the cortex.  The outer, surface layer, which consists of overlapping flattened cells is called the cuticle,

Terminal hair usually does not regresses to become vellus hair once again. The basic exception to this fact is male pattern baldness (ironically, also caused by testosterone known as DHT). Beard hair will not regress back to the peach fuzz type hair by the absence of male hormones, or the introduction of female hormones or anti-androgens.  However, body hair growth can be slowed  in some areas, with the use of hormonal feminization therapies.

TO BE CONTINUED...........UNDER CONSTRUCTION...................................................