Although one of the most common treatments performed with lasers and IPL’s; laser hair removal still remains a regularly discussed topic with some stubborn urban myths about it.
Let us start with the question: What is the difference between temporary laser / IPL hair removal and permanent laser / IPL hair removal?
When the hair root is not sufficiently heated to kill the hair papilla the hair will shed, but a new hair will grow again from the same papilla. The hair free period can be up to 3 months.
On the other hand if the papilla is killed there will not grow another hair from it.
Shedding of the hair after a treatment does not indicate permanent results
How does laser hair removal work?
The light emitted from the handpiece gets absorbed by melanin which then heats-up. Because the hair root contains a high concentration of melanin there will be enough heat created to damage the tissue surrounding the hair root to such extend that no further hair growth will occur from that specific hair papilla.
To achieve this there must be enough energy (light) available for a sufficient period of time to heat up the hair root. The real secret to success lies in the energy and pulse length combination. Too much energy in a too short period will lead to destruction of the hair itself without sufficient damage to surrounding tissue (shedding of the hair and temporary results). Too little energy will cause very little or no visible results and sufficient energy with a wrong pulse length will also deliver temporary results.
What happens to the skin since it also contains melanin?
It also heats-up. The melanin in your skin is exactly the same pigment as the melanin in your hair. For this reason skin cooling is a very important component of successful permanent hair removal. The epidermis must be cooled during the period that the laser emits the light beam.
This cooling will not affect the heating-up of the hair root since the skin is a very weak conductor of heat and both the cooling of the epidermis and the heating of the hair root are local processes.
Thus the lighter the skin is the safer the procedure will be and the darker the hair gets the better the treatment results.
Cooling gels are very ineffective in protecting the skin during a treatment. This is because of two simple reasons:
Firstly, the cooling gel will be pressed away by the handpiece and thus not provide a sufficient protection layer.
Secondly, if the cooing gel is not pressed away and a distance is left between the handpiece and the skin the light will be reflected and refracted to such an extent by the gel that the treatment will not achieve the desired results.
In practise the use of cooling gel during a treatment indicates that you should only expect temporary results and not permanent results.
What is the difference between a laser treatment and an IPL treatment?
Lasers only emit one wavelength of light at a given time. This means that less elements in you skin and body will react to the light during a treatment and the treatment will be much more focused. (Using a wavelength of 750nm will not affect elements that react to 680nm.) For this reason you will get lasers that are suitable for hair removal as well as lasers that cannot do hair removal. There is also no (or very little) loss of energy.
IPL’s emit a broad range of light that is filtered (usually) between 500nm and 1100nm. Because of this the handpiece must be placed directly onto the skin or else too much loss of energy will occur. In turn this leads to a high heat build-up in the epidermis. This is also the reason why IPL’s are not suitable for dark skin types.
Various manufacturers claim that their IPL’s are safe for dark or all skin types. This is only achievable if you lower the energy to such a level that permanent hair removal can no longer be achieved.
Can permanent laser / IPL hair removal be achieved on all skin types and hair types?
No. The hair and hair root must contain a sufficient concentration of melanin to generate enough heat to destroy the hair papilla.
The ideal person for permanent laser / IPL hair removal will have very light skin and dark hair. However, this ideal person exists rarely in reality. The bigger the contrast between skin and hair, the better the results will be.
Is laser more dangerous than IPL?
No. In the hands of a well trained therapist both technologies will provide the desired results in a safe manner.
Because of the wide range of wavelength and heat build-up, IPL’s may lead more easily to skin burns.
If you have any experience or thoughts about this topic; please let us know by posting a comment on your experience.