Derma roller do and don'ts....

http://www.theprivateclinic.co.uk/treatments/dermal-roller/?gclid=COmsp6vc7qgCFcJP4Qod7C8yCQ

http://www.freedomhealth.co.uk/aesthetic-and-cosmetic/genuine-dermaroller-therapy/179/

For acne scars.