They can make the scars less noticable, when done properly. Further improvement can be obtained, with a repeat session, if these are crater shaped scars. Pitted and keloid scars do not respond well to these methods. A combination therapeutic approach is usually best, if there is a mix of scar types. Punched out and pitted scars can be removed surgically, or with cross method, while bound down scars are treated with subcision. Shallow, crater scars can benefit from dermabrasion or laser re-surfacing. These options, and risks of each, are best discussed with your dermatologist, after he/she does a thorough history and physical exam.