4. Not all lasers are equal

While all lasers operate on the same principle of creating controlled micro-injuries to the skin, different lasers target different parts of the skin structure.

This is because different lasers emit different wavelengths which are then absorbed by the various elements in the skin, such as water, blood vessels and pigment. "All of these absorb different wavelengths, initiating a thermal reaction in the different elements," explained Dr Phua.

She offered the example of treating two different forms of pigmentation with different types of lasers. Port-wine stains are red birthmarks formed by blood vessels, which in turn, contain haemoglobin. This absorbs a shorter wave length of laser to heat and shrink, thus lightening in the process. However, in the case of melasma (pigmentation caused by hormonal fluctuations) the pigment cells or melanin absorb a long wavelength laser to scatter and destruct, hence lightening in the process. A short wavelength of laser would not be appropriate in this case.

Read also: AsiaOne Health's review of the ProFractional-XC laser