Important questions
The goal of laser hair removal is to permanently eliminate the factors responsible for hair growth, in order to prevent hair from growing back.
Important questions:
What is responsible for hair growth?
The papilla, the matrix and most importantly, the mother cells in the interphase protuberance located between the external reticular layer and the connective tissue.
How are these factors eliminated?
Photo thermolysis is the theory which determines the parameters needed by a laser in order to eliminate hair without harming epidermal tissues.
How does this process occur?
Hair follicles contain a natural chromophore, known as melanin. (A chromophore is a molecule capable of absorbing light).
When a chromophore absorbs laser light, it is transformed into heat, raising temperature and destroying not only the follicle, but also everything that is near it (that is, the papilla, matrix, and mother cells).
How does a laser avoid damaging other skin structures?
Through different processes:
- By nature and color, other skin structures cannot absorb this wave length, or absorb it only minimally.
- The intensity used by the laser is perfectly adapted to the situation.
- The laser shot is extremely short, resulting in rapid heat dissipation.
- Through external protection mechanisms, such as applying a source of cold to the surface of the skin.
How many treatment sessions are required?
Hair undergoes several phases, mainly an active phase and a rest phase.
During the active phase, hair is visible, indicating the presence of melanin, a chromophore capable of absorbing luminous energy, and stopping at hair roots.
During the rest phase, hair is not visible, and therefore cannot be treated.
Since all hair can never be in the active phase at the same time (approximately 20% of hairs are at a time), several treatment sessions are required in order to coincide with the active phases.
Which laser device is best adapted to permanent hair removal?
The international scientific community unanimously agrees that the most efficient laser for permanent hair removal is an 810 nm diode laser, with a 20 to 60 J/cm2 energy density, a 15-100 millisecond shot length, and an integrated sapphire to cool the surface of the skin.
Why?
Diode lasers which have these parameters are used worldwide in laser hair removal.
Results have been tested for over ten years, and have been scientifically proven and described based on many clinical studies both in the United States and in Europe.
The combination of these parameters (810 nm + 15-100 ms pulse + 20-60 J/cm2 for each shot + integrated cooling tip reaching less than 4°C) are optimal for stopping hair growth without damaging adjacent tissue.
