The alexandrite laser is slightly more effective with fair skin types; the SHR mode is clearly more effective with dark skin types. Regarding painfulness, the SHR mode is clearly superior. In terms of speed, the two systems are comparable. The alexandrite laser is more user-friendly because of its light and small handpiece.
The major advantages of the SHR mode are its effectiveness in dark skin types and its lack of pain. The alexandrite laser is slightly more effective with fair skin types, slightly faster and its handling is considerably more comfortable. None of the two systems has yet brought about a breakthrough with fair hair.
Laser parameters seem to be important in choosing the ideal laser for the patient. With lower fluences, temporary removal rather than permanent is achieved. studied the effect of low fluence photoepilation on hair follicles with findings suggesting catagen transition of anagen hair follicles. Long term hair removal largely depends on hair color, skin color and the tolerated fluence. It is said that when optimal parameters are used, each treatment session leads to about 15–30% hair loss. In this study, six months after three sessions, only one third of initial hair was completely lost with the Nd: YAG system. This result may be related to the number of sessions. In their study that at least four to five sessions are necessary for an acceptable result with the Nd: YAG laser.
The effectiveness of different optical devices for hair removal varies significantly among patients due to anatomical location, skin type, hair color, hair thickness, duration of the hair follicle cycle and androgen status.
Although there is no obvious advantage of the SHR mode IPL system over the others in terms of treatment outcome, the Alexandrate laser is still the most efficient and painless light source in comparison with the Nd: YAG and IPL of the SHR mode. Despite the continuous efforts for the development of new laser systems in permanent hair removal with a minimal number of session, we can state that there is as yet no developed safe and efficient light source that meets the expectations