When you look closely at your cheekbones in the mirror, you may notice that the acne has healed, but tiny marks are still left behind in the same spots. Some are deep and round, some are narrow and sharply indented, and some are hard to define but look shadowed.

To start with the conclusion, the treatment that works best for acne scars depends on their shape. They are commonly classified into three types: boxcar, ice pick, and rolling, and even with the same "scar laser," the depth and area each device reaches can differ. The most common misconception we hear in consultations is the expectation that "one laser will remove everything."

Why we first classify the scar shape

The three shapes are not just differences in appearance—they show how the scar formed. Boxcar scars have a broad top and steep sides, with depths ranging from about 1 to 4 mm. Ice pick scars are narrow, deeply pitted marks, usually within 1–2 mm in width; although the surface area is small, they often extend deep into the dermis.

Rolling scars are caused by fibrous bands beneath the dermis pulling on the skin, creating a wavy, depressed surface. Unlike the other two scar types, the border on the surface is often not clearly defined, and the shadow becomes more visible when light is shone from the side. This classification is the starting point for choosing treatment. Even when people say "scar treatment," what each device can reach and how deeply it works can be quite different.

For boxcar scars, resurfacing and RF microneedling are often used

Boxcar scars are clearly indented at the surface, so when the edges are precisely refined, they become less noticeable. Ablative fractional lasers such as CO2 and Er:YAG shave down the edges to reduce the step-off, and deeper boxcar scars are often treated with RF microneedling* as well.

RF microneedling uses fine needles to penetrate the dermis and deliver radiofrequency energy deep into the scar. The idea is to stimulate new collagen in the area and gently lift the scar base. In general, meaningful improvement usually requires 3 to 5 sessions at 4- to 6-week intervals, so it is good to know in advance that this is not a one- or two-treatment procedure.

RF microneedling*: A device that inserts fine needles into the skin and delivers radiofrequency energy deep into the dermis. You may often see it under names such as INFINI, Potenza, or Secret RF.

For ice pick scars, punch techniques or TCA CROSS are used

Ice pick scars are narrow and deep, so surface-resurfacing methods alone usually do not remove them well. Treatments that reach deep into the dermis are needed. At that point, a punch tool may be used to remove only the scar and close the area with sutures, or TCA CROSS may be selected, in which a high-concentration TCA solution is applied only to the inside of the scar to stimulate new collagen formation.

A punch excises a narrow, deep scar—usually less than 1 mm wide—and closes it again, so results tend to appear faster than repeatedly treating the same number of scars with RF microneedling. However, because it is a precise procedure for one or two spots at a time, it is often combined with other scar treatments for people with rough overall texture.

For rolling scars, subcision and collagen boosters are often combined

Rolling scars are formed by fibrous bands beneath the dermis pulling on the skin, so even if the surface is resurfaced or new collagen is added, the same shadow can reappear if the band remains. For that reason, a procedure called subcision is often performed first to release the band. A fine needle is inserted under the skin and moved side to side to loosen the fibrous band.

After subcision, many people also receive a collagen booster (such as Juvelook, Rejuran, or Sculptra) or PRP* to help prevent the area from sticking down again. The approach is to release the band, fill the space, and then combine it with surface treatments as collagen is rebuilt. For rolling scars, it is common to combine two or three treatments rather than rely on just one.

PRP*: A platelet-rich plasma prepared from your own blood. It contains growth factors involved in collagen production and is often used to support skin recovery.

Three things that often cause confusion during consultation

First, very few people have only one type of scar. Many have boxcar scars on the cheekbones, rolling scars on the chin, and ice pick scars near the nose. So if you try to finish everything with just one treatment, some areas will remain. Asking, "How would you classify this scar area?" during consultation can make the treatment plan much clearer.

Second, the number of sessions and the interval between them vary greatly depending on scar depth. As a basic guideline, 4 to 6 sessions at 4- to 6-week intervals are common, and deep boxcar or ice pick scars may require 6 to 10 sessions. Finally, if you do not keep up with sun protection during recovery, PIH (post-inflammatory hyperpigmentation) can develop in the same areas and blur the results. This article is a general information overview, and scar classification and treatment planning should be discussed with a doctor who can examine your skin in person.