How does laser hair removal work?
Laser hair removal uses laser technology and targets the melanin in the hair follicle. By using a laser emitter, a laser breaks down the melanin and destroys the hair follicle, the hair will not grow back again. In the market, there are 1064nm long pulse laser, 808nm diode laser, and Intense pulse light for hair removal. The principle of Laser hair removal works is due to the light of the laser beam can be converted to heat.
The light is targeted at the pigment (melanin) in the hair. The dark pigment absorbs the light and converts it to heat.
The heat then affects the hair follicles to prevent hair growth. To destroy a hair follicle, the bulb of the hair follicle where the blood supplies the hair with oxygen to grow needs to be destroyed as well as the stem cells which are responsible for hair regeneration. To be able to do this, a temperature of about 70 degrees needs to be reached.
Once the hair follicle has been destroyed, it is almost impossible for future growth to take place. 80-95% of hair is removed during the treatment, although this can depend on the patient’s age and the area being treated. It is worth noting that in 10% of cases, the treatment may not work, even if patients show a good indication for treatment.
Diode laser hair removal principle
Diode laser for hair removal is using the 808nm wavelength.
In diode laser, the hair removal principle of selective photothermolysis applies where the chromophore is melanin in the hair shaft itself and the bulge. However, the same chromophore can be found in skin pigment. Some parts of the body, such as underarms or the pubic area, are more pigmented.
IPL laser hair removal principle
IPL is an intense pulse light and uses 640nm-1200nm for hair removal.
For IPL, The light that comes out of an IPL device is absorbed by the pigment in the hair, causing a buildup of energy which turns to heat (think of a black T-shirt on a sunny day). The heat travels down the hair and disables or destroys the cells that make new ones.
Long pulse ND YAG Laser hair removal principle
Long pulse laser using the 1064nm wavelength.
It works on the principle of selective photothermolysis—the laser damages the hair follicle without damaging the skin. Shorter Nd: YAG pulses are also effective in hair reduction while maintaining better comfort for the patient.
Watching the video for the laser hair removal treatment.
Understanding the hair growth cycle of the hair
We should know that 1 session of laser treatment cannot remove all the hair because the hair has a growth cycle. Hair growth has 3 different stages of growth and not all hairs grow at the same time. This is the reason that why you can observe sometimes when you wax about a week later there is hair starting to grow again. Usually, these are not the same hairs you waxed a week ago, they would be hairs from another follicle that were at a different stage of growth.
This is the 1st phase of the hair growth cycle. It is the active growth phase. At this stage, the bottom of the hair follicle (the bulb) is attached to the dermis and its blood supply through the dermal papilla. This is the best period to remove the hair.
This is the 2nd phase of the hair growth cycle. the transition phase. The hair follicle begins to die and enters the catagen phase
the resting phase. In this phase, the remains of the hair bulb are inactive and the attached hair easily falls out.
How to use a laser hair removal machine?
- Shaving: You should shave the target area 1 or 2 days before the hair removal treatment
- Apply the cooling gel： Apply laser conductor gel to ensure effective penetration of the laser beam
- Hair Removal： The hair removal process will begin. Comfortable treatment with no pain. Generally 20 – 30 mins depending on area.
- Laser aftercare hydration： Laser aftercare will be applied to minimize skin irritation. Repeat sessions until the hair is completely removed.