Greetings. Dermaroller or micro needling is an effective treatment for balding with studies showing variable yet positive results. If done at the clinic it's usually done with longer needles along with platelet rich plasma therapy or meso therapy. It can be done with smaller needles as home based therapy with shorter needles - however this must be cleaned with sterilizing solution before use as guided by your dermatologist. See a qualified dermatologist near you. Further queries may be sent on follow up messaging. Warm regards