Ice Pick scars, being the most common, get their name from the actual formation of the scars. As the name suggests, they are shaped like the hole left from an ice pick. The scars are deep and narrow, which makes it difficult for them to be filled up naturally with collagen and some are too deep to heal entirely. Ice pick scars are usually less than 2mm across.
Boxcar scars are wider and more rectangular with vertical edges as compared to ice pick scars. Boxcar scars are most commonly found on the temples and cheeks. While these scars can be deep or shallow, the majority of Boxcar scars are not as deep as Ice Pick scars.
Rolling scars are the least common scar type of the three. These scars are typically shallow and wide. Caused by damage under the surface of the skin, rolling scars are round and give the skin a rolling, wave-like appearance.