You may use a dermaroller as scar removal tool. The idea is based on the fact that our skin forms scar tissue too quick, long before the body has a chance to fully regenerate the damaged tissue.
On the other hand, small areas like a syringe needle marks, heal without leaving a trace. So by creating micro damage to the scar tissue, you may trick the body to completely heal the scar, or at least make it less noticeable.
That is the theory. In practice, a dermaroller is a handle with a roller, which is covered with needles.
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Dermarollers come in variety of needles diameter and length, depending of the treatment area.
Roll the dermaroller upwards 10 times. Now roll sideways 10 times more. The procedure is over. You should repeat it after complete recovery, which means one procedure in about 3-4 days.
Does it work? That’s a difficult question, since full recovery may require months if not years of regular rolling. So the only way to find out if dermaroller will help you, is to check for yourself. They are cheap, so go try one.