Why Nd: YAG is preferred over diode laser?
Nd YAG laser has a longer wave length than diode laser. So, when Nd: YAG is used, less energy is absorbed at epidermis level and more energy is absorbed at deeper dermis level where route of hair is present. As wall of hair follicle has cells containing melanin and other surrounding tissue does not contain melanin, by Nd YAG laser damage to the hair follicle is more & deeper and damage to surrounding tissue is lesser. So, also, effect of Nd: YAG Laser, sub ablative rather than destructive, in comparison to diode laser. As Indian skin has less contrast with hair, laser longer wave length like Nd YAG is preferable to protect dermis. As diode laser rays are absorbed more by melanin which is at superficial level as compared to melanin of the wall of hair follicle, so, less energy reaches at greater depth of hair bulb follicle. So, effective fluence of diode laser is the richest in lesser quantity as compared to effective fluence of Nd YAG. Nd: YAG laser rays are less absorbed by melanin of
