Acne scars come in two fundamentally different types based on how your skin responds to the inflammation and damage: scars that create indentations below the skin surface, and scars that form raised bumps of excess tissue. Understanding which type you have is crucial because it directly determines which treatments will actually work for you. A treatment that smooths rolling indentations, for instance, won’t flatten a raised keloid scar, and vice versa.
The difference isn’t just cosmetic—it affects everything from how noticeable the scar becomes over time to whether it will respond to lasers, needling, or other interventions. Most acne scars fall into one of five main categories, each with distinct characteristics that tell you something about the injury beneath your skin and what healing approach will help. Some scars respond remarkably well to modern treatments and can nearly disappear, while others are notoriously stubborn and require multiple sessions or combined approaches to see real improvement. This article breaks down each scar type, explains why they form differently, and covers what your treatment options actually are.
Table of Contents
- What Are the Two Main Categories of Acne Scars and How Do They Form?
- Ice Pick Scars and Boxcar Scars: The Two Types of Indented Scars You’ll See Most Often
- Rolling Scars and What Skin Aging Reveals About Them
- Hypertrophic Scars and Keloids: When Raised Tissue Becomes the Problem
- How Scar Type Directly Determines Which Treatments Will Actually Work
- Combination Treatments and Why Single Approaches Often Fall Short
- Realistic Expectations: What Modern Treatment Can Actually Achieve
- Conclusion
What Are the Two Main Categories of Acne Scars and How Do They Form?
Your skin has two opposite ways of responding to severe acne damage, creating two opposing scar types. Depressed scars form when the inflammatory damage destroys collagen and skin tissue, leaving a permanent indentation or hole below the normal skin surface. These are the most common acne scars. Raised scars form when your skin overcompensates during healing, building up excess collagen and tissue that stands above the surrounding skin—these are less common but can be stubborn.
The type that forms depends partly on genetics and partly on the inflammation’s severity. People prone to overproducing collagen during healing are more likely to develop raised scars, while those whose skin doesn’t rebuild collagen effectively are more likely to end up with indented scars. This is why two people with the same type of acne can end up with completely different scar patterns. Understanding which category yours falls into is your first step toward knowing whether you need treatments that fill indentations or flatten raised tissue.
Ice Pick Scars and Boxcar Scars: The Two Types of Indented Scars You’ll See Most Often
Ice pick scars are narrow, deep holes that start wide at the skin surface and taper to a point deeper in the skin—they look like the skin was punctured by an ice pick, which is why dermatologists gave them that name. These are considered among the most challenging acne scars to treat because of their depth and narrow opening; the tissue damage runs deep, making it hard for treatments to reach the entire scar. They tend to concentrate on the cheeks and temples where acne often erupts on oily skin.
Boxcar scars are the opposite problem: they’re broad, box-shaped depressions with steep or near-vertical walls, usually forming in areas with thicker, less elastic skin like the jawline and chin. While they’re generally easier to treat than ice pick scars because they’re broader and shallower, they’re still challenging because treatments need to level the sharp drop-off between normal skin and scar floor. Some people have both types of indented scars on different parts of their face, which complicates treatment planning because the therapist may need different approaches in different zones.
Rolling Scars and What Skin Aging Reveals About Them
Rolling scars are the gentler-looking cousins of ice pick and boxcar scars—they have soft, smooth-edged indentations with gentle slopes rather than sharp walls, and they’re often not very noticeable at first glance. This deceptive mildness hides their real problem: the scarred tissue underneath the skin is actually tethered or anchored, pulling the skin surface down into a gentle wave. Rolling scars tend to respond well to treatments like microneedling, subcision (where a needle is used to physically break the underlying tethering), and laser treatments that stimulate collagen production and release those anchored tissues. However, rolling scars become increasingly visible over time.
As you age and your skin naturally loses elasticity and collagen, those gentle slopes become more pronounced because the surrounding skin loses the firmness that once camouflaged them. This means a rolling scar that’s barely noticeable in your twenties might become quite visible in your forties or fifties unless treated. If you have rolling scars, getting them addressed sooner rather than later may prevent the visibility problem from worsening with age. Preventive treatment is sometimes a smarter choice than waiting to see if they become more obvious.
Hypertrophic Scars and Keloids: When Raised Tissue Becomes the Problem
Hypertrophic scars are raised bumps and ridges, usually about the same size as the original acne lesion that created them. They occur when your skin produces excess collagen during healing but stops producing it once the scar reaches roughly the original wound’s size. Most hypertrophic acne scars appear on the back, chest, and other non-facial areas where skin is thicker and tends to heal with more collagen buildup. On the face, they’re less common, but when they do appear, they’re often more psychologically bothersome because they’re visible and bumpy.
Keloid scars are a more aggressive version of hypertrophic scars—they don’t stop at the original wound’s size but keep growing, sometimes developing “arms” or shoots of scar tissue that extend outward in unpredictable directions. People with darker skin tones are genetically more prone to keloid formation, which is why keloids are an important consideration for dermatologists treating acne in Black, Hispanic, Asian, and other populations where keloid risk is elevated. Unlike hypertrophic scars, keloids may continue growing months or even years after the original acne healed, and they often recur after treatment. This makes keloid management a longer-term commitment that may require ongoing medical supervision.
How Scar Type Directly Determines Which Treatments Will Actually Work
Different scar types need different approaches because the underlying problem is different. Indented scars (rolling, boxcar, ice pick) need treatments that either fill the depression, level the skin surface, or stimulate the skin’s collagen production to gradually raise the depressed area. Rolling scars specifically respond well to subcision and microneedling because releasing the tethered tissue and triggering collagen remodeling addresses the root problem. Laser treatments also work by creating controlled injury that stimulates collagen and improves surface texture.
Raised scars (hypertrophic and keloid) need treatments that flatten or reduce the excess tissue—these include steroid injections, laser treatments designed to reduce scar tissue, surgical removal, or pressure therapy. Some of these approaches nearly eliminate scars in responsive cases, while others primarily improve appearance without complete removal. The important limitation here is that no single treatment works universally well for everyone; individual skin type, scar age, scar location, and genetic healing tendency all affect how well any given treatment will work. This is why dermatologists often recommend starting with less invasive options and moving to more aggressive treatments only if the first approach doesn’t deliver results.
Combination Treatments and Why Single Approaches Often Fall Short
Because acne scarring is complex—with different scar types often appearing on the same face, sometimes layered on top of each other—dermatologists frequently use combination approaches rather than relying on a single treatment. A patient might receive microneedling for rolling scars combined with laser treatment for texture and discoloration, then targeted steroid injections for any hypertrophic spots. This layered approach works because it addresses multiple problems simultaneously: the tethering, the collagen deficit, the excess tissue, and the discoloration.
However, combination treatments mean longer overall timelines, higher costs, and more appointment visits. If you’re considering treating your acne scars, it’s worth discussing with a dermatologist whether multiple sessions of a single treatment might work instead, or whether the combination approach really is necessary for your specific pattern. Some people see dramatic improvement with just subcision or just laser treatments, while others genuinely do need the combined approach. The upfront consultation with a professional who can assess your specific scar pattern is time well spent before committing to treatment.
Realistic Expectations: What Modern Treatment Can Actually Achieve
Modern scar treatments have improved dramatically, and dermatologists can now make significant improvements that would have been impossible a decade ago. Some scars respond so well to treatment that they become nearly invisible—particularly rolling scars treated with the right combination of microneedling and laser work. Other scar types, especially deep ice pick scars or aggressive keloids, may improve substantially but remain somewhat visible even after optimal treatment. The goal of treatment is usually meaningful improvement rather than perfect erasure.
Realistic expectations matter because false hope leads to disappointment and wasted money. Understanding that your ice pick scars might become 60-70% less noticeable rather than completely invisible helps you make informed decisions about whether treatment is worth the time, cost, and discomfort. Similarly, understanding that keloid scars might require maintenance treatment over years helps you prepare mentally and financially. The best outcomes come when patients understand exactly what their specific scar type can achieve with evidence-based treatments, and work with a dermatologist who’s honest about both the potential and the limitations.
Conclusion
Acne scars tell a story about how your individual skin healed after inflammation, and that story determines what will actually help. Whether you’re dealing with depressed scars that create indentations or raised scars that create bumps, modern dermatology offers evidence-based treatments that can meaningfully improve appearance. The five main types—ice pick, boxcar, rolling, hypertrophic, and keloid—each respond differently to microneedling, laser therapy, subcision, and other approaches, which is why professional assessment matters.
If you’re considering scar treatment, start by seeing a dermatologist who can accurately identify your scar type and explain realistic outcomes specific to your situation. Combination treatments often work better than single approaches, and patience matters; many effective treatments work by triggering your skin’s own collagen remodeling, which takes time. With the right approach matched to your scar type, meaningful improvement is absolutely possible.
