The Four Kinds of Acne Scars and What Each Needs

What are the four kinds of acne scars?

Acne scars fall into two broad families and four practical types. The first family is atrophic, or pitted, scars, where tissue was lost during healing — these are the common ones, and they split into ice pick, boxcar, and rolling. The second family is raised scars, where too much tissue formed, giving hypertrophic and keloid scars. A treatment review of atrophic scars matches each pitted type to specific procedures, which is exactly why identifying the type comes first 1Ref 1Boen M, Jacob C (2024).Atrophic Postacne Scar Treatment: Narrative Review.Atrophic acne scars are treated by modality matched to shape — subcision for rolling scars, fractional laser and microneedling for boxcar scars, TCA CROSS and punch techniques for ice pick scars — and combination approaches outperform single modalities..

The reason this map matters is that the tools are shape-specific: subcision releases a tethered rolling scar, resurfacing softens a boxcar wall, and a focused acid rebuilds an ice-pick pit 1Ref 1Boen M, Jacob C (2024).Atrophic Postacne Scar Treatment: Narrative Review.Atrophic acne scars are treated by modality matched to shape — subcision for rolling scars, fractional laser and microneedling for boxcar scars, TCA CROSS and punch techniques for ice pick scars — and combination approaches outperform single modalities.. A single face usually carries a mix of types, not just one. For the full side-by-side of what each procedure does, an acne scar treatment comparison lays the options out; this page is about recognizing what you have before you get there.

How acne scars actually form

Understanding why the shapes differ makes them easier to tell apart. A scar forms when inflammation from acne — especially deep, cystic acne — disrupts the skin's collagen during healing. When the healing response rebuilds too little collagen, the surface caves in and an atrophic, pitted scar results; when it rebuilds too much, the tissue heaps up into a raised scar. The same underlying event, a burst of inflammation, can therefore leave opposite-looking marks on two people.

The depth and duration of that inflammation is what sorts the atrophic scars into ice pick, boxcar, and rolling. A narrow, deep pocket of damage tends to leave an ice pick track; a broader area with defined edges leaves a boxcar; damage that also tethers the skin to the tissue below leaves a rolling scar. This is one reason picking and squeezing tend to make scarring worse — they extend the inflammation that decides how much collagen is lost or overbuilt.

Ice pick scars: narrow and deep

Ice pick scars are narrow, steep-sided pits that plunge into the skin like a tiny puncture, as if an ice pick had been pressed in. They are small at the surface but deep, and that depth is what makes them stubborn: surface resurfacing cannot reach the bottom of the track. They turn up most on the cheeks, where pores were widest.

Because a laser passes over the surface without reaching the base, ice pick scars are matched to focused techniques that rebuild each pit individually — most often TCA CROSS, where a high-strength acid is applied precisely into the pit, or punch excision for the deepest ones 1Ref 1Boen M, Jacob C (2024).Atrophic Postacne Scar Treatment: Narrative Review.Atrophic acne scars are treated by modality matched to shape — subcision for rolling scars, fractional laser and microneedling for boxcar scars, TCA CROSS and punch techniques for ice pick scars — and combination approaches outperform single modalities.. TCA CROSS for deep ice-pick scars is a slow, repeated process rather than a single fix, and TCA CROSS for ice pick scars is generally preferred over broad resurfacing precisely because it concentrates on the narrow track.

A useful tell is the width: ice pick scars are usually too narrow to fit a fingertip into, and in good lighting they read as tiny dark dots rather than shadowed craters. They are often mistaken for large or empty pores, but a pore is a normal opening while an ice pick scar is a fixed, scarred track that does not clear with cleansing or shrink with toner.

Boxcar scars: sharp walls

Boxcar scars are round or oval depressions with defined, near-vertical walls and a flat base — like a small crater pressed into the skin. They are wider than ice pick scars and often shallower than they look, which is why they respond to resurfacing that softens their sharp edges. They cluster on the cheeks and temples, where the skin is thicker and can hold a walled shape.

Because the problem is walled edges rather than a deep track, treating boxcar scars usually means resurfacing to blur the walls: a fractional laser for deeper ones, or microneedling for shallow boxcar scars, with punch techniques reserved for a single sharply defined crater 1Ref 1Boen M, Jacob C (2024).Atrophic Postacne Scar Treatment: Narrative Review.Atrophic acne scars are treated by modality matched to shape — subcision for rolling scars, fractional laser and microneedling for boxcar scars, TCA CROSS and punch techniques for ice pick scars — and combination approaches outperform single modalities.. The distinction from ice pick scars is practical — resurfacing that would skim past an ice pick pit can genuinely soften a boxcar wall.

A quick way to separate a boxcar from a rolling scar is the edge: a boxcar has an abrupt rim you can almost trace with a fingertip, while a rolling scar fades gradually into normal skin. Shallow boxcar scars can look deceptively minor in flat, head-on light and then appear clearly in side lighting, which is why the lighting you assess yourself in matters as much as the scar itself.

Rolling scars: broad, tethered dips

Rolling scars are broad, shallow depressions with sloping edges that give the skin a wavy, undulating look, most visible in raking side light. Unlike the other atrophic types, the surface itself is relatively normal — the scar is pulled down from beneath by fibrous bands that tether it to deeper tissue. That tether, not the surface, is the thing to treat.

a rolling scar is anchored from below, so releasing the tether matters more than resurfacing the surface. Because of that anchor, rolling scars respond to release: subcision cuts the tethers so the dip can lift, and treating rolling acne scars often layers collagen-building on top afterward 1Ref 1Boen M, Jacob C (2024).Atrophic Postacne Scar Treatment: Narrative Review.Atrophic acne scars are treated by modality matched to shape — subcision for rolling scars, fractional laser and microneedling for boxcar scars, TCA CROSS and punch techniques for ice pick scars — and combination approaches outperform single modalities.. Resurfacing a rolling scar without releasing the tether leaves the anchor in place and the depression largely where it started.

Rolling scars are also the type most affected by aging. As skin loses its own collagen over the years, tethered dips can look deeper in your forties than they did in your twenties, even with no new acne. That is worth building into expectations, since the surface was never really the problem — the anchor beneath it, plus the gradual thinning of the skin around it, is.

Raised scars: hypertrophic and keloid

The fourth kind runs the opposite direction. Instead of losing tissue, the skin makes too much during healing, leaving a scar that sits above the surface — firm, often pink or darker than nearby skin, and sometimes itchy or tender. Hypertrophic scars stay within the borders of the original acne lesion; keloids grow beyond them. Both are more common on the chest, shoulders, back, and jawline than on the cheeks.

This is a genuinely different problem from pitted scars, which is why the pitted vs raised acne scars distinction matters before choosing any treatment. Raised scars are not resurfaced or subcised — those methods are for lost tissue. They are instead flattened with approaches aimed at excess tissue, such as in-scar steroid injections or silicone, essentially the mirror image of the atrophic strategy. Getting the atrophic vs hypertrophic scars call right early is what prevents a mismatched, wasted treatment plan.

Why most faces have more than one type

Real acne scarring rarely arrives as a single tidy type. Most people who scarred from moderate or severe acne carry a mix — a few ice pick pits near the nose, some boxcar craters on the cheeks, and rolling undulations across a broader area — sometimes with a raised scar or two along the jaw or on the chest. A mixed face is the norm, not a complication or a sign that something went unusually wrong.

The mix is exactly why identifying types matters more than searching for one label. A plan that treats only the rolling scars leaves the ice pick pits untouched, and the reverse is equally true. Sorting your own skin into 'these near the nose are ice pick, those on the cheek are boxcar, that whole patch is rolling' is the groundwork a clinician builds a combined plan on. It also sets honest expectations: a face carrying several types will need more than one approach, and improvement will land unevenly across them rather than all at once.

What is not a scar: red and brown marks

Not every mark acne leaves behind is a scar, and this distinction saves people a great deal of money. Flat red or purple marks — post-inflammatory erythema — and flat brown spots — post-inflammatory hyperpigmentation — are changes in color, not changes in the skin's surface. Run a finger across them and the skin feels smooth; a true scar has depth or height you can feel, while a mark is level with the skin around it.

because these are color rather than texture, flat post-acne marks tend to fade on their own over months, especially with steady sun protection. A true scar does not fade this way; it is a structural change that stays until it is physically treated. The practical takeaway is that a flat, smooth discoloration usually calls for patience and sun care, not a procedure, whereas a pitted or raised scar is what warrants the treatments this page describes.

The reason this matters financially is that laser and needling procedures priced for true scars do little for flat discoloration, which responds instead to pigment-focused care and time. Treating a brown mark as if it were a boxcar scar is a common and expensive mistake, and it is avoided by the simplest test there is: if the skin feels smooth under a fingertip, it is a mark, not a scar.

How to identify your scars — and the one thing that helps all of them

Two simple checks separate the types at home. First, look in raking side light from a window or a single lamp: rolling scars and boxcar edges cast small shadows that flat marks never do. Second, gently stretch the skin — a rolling scar shallows out as its tether releases under tension, while an ice pick pit stays put. What you can feel with a fingertip matters as much as what you see.

Whatever the type, the single most effective scar strategy is preventing new ones by controlling active acne. Guidelines recommend oral isotretinoin for severe, scarring, or refractory acne precisely because stopping new lesions protects the skin better than any procedure repairs it 2Ref 2Reynolds RV, Yeung H, Cheng CE, et al. (2024).Guidelines of care for the management of acne vulgaris.The AAD strongly recommends oral isotretinoin for severe, scarring, or refractory acne, reflecting that preventing new lesions is the most effective way to limit new scarring.. A common worry about that medication — a supposed link to inflammatory bowel disease — is not supported by large-scale data, which found no clinically meaningful increase in IBD risk 3Ref 3Tan NKW, Tang A, Lim RK, et al. (2023).Isotretinoin and the risk of inflammatory bowel disease and irritable bowel syndrome: A large-scale global study.Large-scale data do not support a clinically meaningful increase in inflammatory bowel disease risk with isotretinoin, addressing a common fear about the medication used to control scarring acne.. Once acne is quiet, the procedure choices — from fillers for acne scars to fractional laser scars — are matched to the type you identified here, and a full acne scar treatment comparison covers them in depth.

One practical habit outlasts any single check: photographs taken in consistent lighting, a few months apart, are the most reliable way to judge whether anything is truly changing. Memory exaggerates in both directions — a stable scar can feel like it is worsening on a bad day, and the slow fading of a flat mark can go unnoticed. A dated photo settles the question and keeps expectations tied to what the skin is actually doing.