Laser hair removal is a relatively new cosmetic procedure designed to permanently remove unwanted facial and body hair by using the light energy from a laser. In order to understand the laser hair removal mechanism and its effectiveness, we have to understand the following basic facts.

Un-Wanted Hairs

Normal skin is not devoid of hairs. Skin usually contains between 700 - 1000 hair follicles per square inch of the body. Now, most of these never produce a noticeable hair but they have the potential to produce visible hairs. Several cultural prejudices and preferences also lay down the principles to label different hairs as wanted or unwanted. There is also contrasting variation about unwanted hairs regarding the two sexes like hair on the chin of a male are not considered unwanted but on a female chin these certainly are unwanted and needed to be removed by hair removal techniques like laser hair removal.

Causes

The culprit responsible for excessive hair growth is our body itself. We can say that it’s normal to have hairs on the body. These hairs are produced as a result of the hormonal changes which take place during puberty, pregnancy and again after menopause. Several other factors like intake of steroids and oral contraceptives also influence the hair growth. This hair growth is not due to some disorder.
The other cause of excessive hair growth is the pathological hair growth which severely affects patients with hormonal disturbances such as the following:

• Poly cystic ovary disease (a disease of ovaries)
• Congenital adrenal hyperplasia (a disease of adrenal glands)
• Hirsutism (a disorder causing excess hair growth in women following a male distribution pattern)
• Hypertrichosis (is excessive hair growth over and above the normal for the age, sex and race)
• Congenital hairy nevi (a pigmented surface lesion present at birth)

Excessive hair growth has been implicated in the pathogenesis of some disease and in the unfavorable outcome of some reconstructive flaps.

Hair characteristics

There are many different types of hair. Hairs come in all colors, shapes, and sizes. Hairs in different areas of the body have different physical characteristics, growth cycles and follicle depths, and all of these factors will affect how we treat the unwanted hairs for hair removal, and the expected results achieved.

Hair Growth Phases

Normal hair goes through a growth cycle in three stages: the anagen, or growing phase; the telogen, or resting phase; and the catagen, or transitional phase. During the anagen phase, hair is susceptible to the laser’s energy, but during the telogen and catagen phases, it is resistant to the permanent effects of the lasers. So the success of the hair removal treatment also depends how much hair of the treated area are in the anagen phase.