If you've shopped for acne scar treatment, you've probably been offered one device as the answer to everything. That's the first warning sign. Acne scars come in distinct shapes, and the shape determines what can reach them. A treatment that softens shallow scars can do almost nothing for a deep, narrow one.
This guide sorts scars by type, matches each to the treatments with the most support, and explains what to expect in sessions, downtime, and results, along with the extra care darker skin needs.
First, make sure it's a scar
The American Academy of Dermatology (AAD) points out in its acne scars overview that a flat spot of color left after a pimple clears is usually post-inflammatory hyperpigmentation (PIH), not a scar. PIH often fades with time and sun protection, and it's treated differently. A true scar changes the skin's texture: it's sunken or raised. The AAD notes that acne scars "rarely go away completely on their own."
Timing matters too. The AAD's acne scar treatment page says scar treatment usually begins after acne is under control, and asks patients to tell their dermatologist about every acne treatment they've used in the past two years, because some scar treatments can cause side effects if started during or soon after certain acne medications.
The scar types
Most acne scars are depressed (atrophic). The AAD says most people who scar develop scars that leave depressions in the skin. Dermatologists sort atrophic scars into three shapes. A 2020 review in Plastic and Aesthetic Research (Callaghan) describes them this way:
•Ice pick scars: narrow (under 2 mm wide) and deep, like a puncture.
•Boxcar scars: 1 to 4 mm across with sharp, defined edges, and relatively shallow.
•Rolling scars: at least 4 mm across with soft, sloping edges. Bands of fibrous tissue tether the skin to the tissue beneath, which creates the wavy look.
Raised scars are a separate group. They include hypertrophic scars, which stay within the original wound, and keloids, which grow beyond it.
Many people have more than one type on the same face, which is why a single-treatment plan often falls short.
Matching treatment to scar type
Ice pick scars: TCA CROSS and punch techniques
Ice pick scars are too deep and narrow for surface resurfacing to reach the bottom.
TCA CROSS (chemical reconstruction of skin scars) uses a fine applicator to place high-strength trichloroacetic acid inside each scar, not across the whole face. A 2015 review in the Journal of Clinical and Aesthetic Dermatology (Hession and Graber) describes it as particularly suited to ice pick scarring. In the original study it cites, 65 patients with skin types IV and V were treated, and most in both concentration groups (82% and 94%) improved by 50% to 70%. The Callaghan review cites another study reporting 73% excellent and 20% good improvement.
Punch techniques remove or lift the scar with a small circular blade, the same tool used for skin biopsies. In punch excision, the scar is cut out and the site is stitched or left to heal. In punch elevation, the base of the scar is lifted level with the surrounding skin. Hession and Graber note that the evidence here is mostly small, older case reports, and that complications such as graft depression or failure can occur.
Rolling scars: subcision and fillers
Because rolling scars are caused by tethering bands under the skin, the fix is to release them.
Subcision passes a needle or blunt cannula beneath the scar to cut those fibrous bands. Hession and Graber describe it as loosening "the fibrotic adhesions that cause the bound-down appearance of rolling scars." In one study they cite, 40 patients rated their improvement at 51%, and investigators rated it at 50% to 60%. They also note hypertrophic (raised) scarring in 5% to 10% of patients in other studies, a risk to raise with your provider.
Fillers lift the depressed area. The AAD notes that fillers add volume and may stimulate collagen, and that "most fillers give temporary results, ranging from 3 months to 2 years."
One filler has a specific FDA acne scar indication. The FDA's premarket approval database lists Bellafill, a collagen gel with PMMA microspheres, as approved on December 23, 2014, for "moderate to severe, atrophic, distensible facial acne scars on the cheek in patients over the age of 21 years." "Distensible" means the scar flattens when the skin is stretched, which is typical of rolling scars and not of ice pick scars. The FDA's summary of safety and effectiveness reports that 64% of treated patients were rated successes at six months, compared with 33% of the saline control group. Bellafill contains bovine collagen and requires a skin test before treatment, and PMMA is long-lasting, so it's a more permanent decision than a temporary filler.
Other fillers are also used for acne scars. If a provider proposes one, ask whether it's FDA-approved for acne scars or being used off-label, and how long it's expected to last.
Boxcar scars: resurfacing
Boxcar scars are shallower with defined edges, so treatments that resurface or remodel the skin can soften them.
Fractional lasers treat a grid of tiny columns of skin at a time, leaving untouched skin in between to speed healing. Ablative fractional lasers (such as CO2) remove tissue and remodel collagen. Nonablative fractional lasers heat tissue without removing the surface. Hession and Graber summarize several studies: in one, 90% of 53 patients reached 51% to 75% improvement after two to five nonablative fractional sessions, and in a small study of 13 patients, ablative fractional CO2 improved scar depth by an average of 66.8%. The Callaghan review cites a study in which a 1,540 nm nonablative laser produced more improvement on boxcar scars (52.9%) than on rolling (43.1%) or ice pick scars (25.9%), which shows how scar type changes the results.
For more on the differences between laser types, see our laser skin resurfacing guide.
Microneedling and RF microneedling create controlled micro-injuries that stimulate collagen. The AAD notes that microneedling is often combined with radiofrequency, chemical peels, or platelet-rich plasma (PRP), and that radiofrequency microneedling may produce less noticeable scars than either treatment alone. In one study Hession and Graber cite, 33 patients treated with skin needling saw scar depth improve by up to 25%. Our guides to microneedling vs. chemical peels and Morpheus8 and RF microneedling cover these devices in more detail.
Chemical peels across the whole face help most with shallow scarring and uneven texture. Hession and Graber describe superficial peels as "modest at best" for scarring. For a mild peel, the AAD describes 3 to 5 treatments spaced 2 to 4 weeks apart.
Raised scars
The AAD lists laser treatment, corticosteroid or other injections, and prescription topical medication for hypertrophic scars. Keloids are often treated with two or more methods because they can return. Options include injections, laser therapy, surgery, or freezing. Resurfacing treatments meant for depressed scars are not the right tool here.
Why combination plans are the norm
Hession and Graber state that "superior results may be achieved when multiple modalities are combined for a multi-step approach to scarring." A typical sequence might use TCA CROSS or punch techniques for ice pick scars, subcision or filler for rolling scars, and a series of fractional laser or RF microneedling sessions to blend the surface.
Here's a typical scenario: someone with rolling scars on the cheeks and scattered ice pick scars on the temples is offered six sessions of one microneedling device. That plan may smooth the surface somewhat, but it doesn't address the tethering under the rolling scars or the depth of the ice pick scars. A plan built around scar type would treat each one with the method that can reach it.
Hold your expectations to what the evidence supports. The same review concludes that "there is no single treatment, or even combination thereof, that can achieve 100-percent improvement of acne scarring." Meaningful improvement is a realistic goal; a perfectly smooth result usually isn't.
Sessions and downtime
Every plan is individual, but a few patterns hold:
•Resurfacing treatments (fractional lasers, microneedling, RF microneedling, peels) are usually done as a series. The AAD notes that the number of laser sessions varies by device.
•Focal procedures (TCA CROSS, subcision, punch techniques) target individual scars and may be repeated or followed by resurfacing.
•Fillers usually take a series of visits, according to the AAD, and temporary fillers need maintenance.
•Downtime ranges from a few days of redness for gentler treatments to longer healing for ablative lasers and deeper procedures. Ask for a specific downtime estimate for each step in your plan.
The AAD notes that medical insurance does not cover acne scar treatment.
Darker skin and PIH risk
Post-inflammatory hyperpigmentation is the major risk for people with medium-brown to deep skin tones. Any treatment that injures or heats the skin can trigger it, and in darker skin it can last for months.
What the evidence says:
•Deeper chemical peels carry a high PIH risk. Hession and Graber report that a medium-depth TCA peel caused PIH in 73.4% of patients in one study, lasting up to three months in some.
•Nonablative fractional lasers need conservative settings. A 2017 evidence review in the Journal of Clinical and Aesthetic Dermatology (Kaushik and Alexis) found that "treatment density is a stronger factor than energy in determining PIH development." It recommends lower density, fewer passes, cooling, longer intervals between sessions, and consistent sunscreen. The authors note that evidence for pre-treatment hydroquinone is lacking and that more studies in skin types V and VI are needed.
•Microneedling and RF have a better safety profile in darker skin. The AAD says that "microneedling is safe for all skin tones" and that radiofrequency and RF microneedling are safe for all skin tones. A review in the Journal of the American Academy of Dermatology (Cohen and Elbuluk, 2016) describes microneedling as potentially offering "a more advantageous safety profile" for skin types IV to VI than traditional resurfacing.
•TCA CROSS treats only the scar. The original TCA CROSS study cited by Hession and Graber was done in patients with skin types IV and V. Because the acid goes only into the scar, less surrounding skin is exposed. That doesn't eliminate PIH risk, so ask about it.
If you have darker skin, ask every provider how many patients with your skin type they've treated with the specific device or procedure, what settings they'll use, whether they'll do a test spot, and what the plan is if PIH appears between sessions.
Who should do it
The AAD recommends a board-certified dermatologist to build the plan, and its consultations weigh scar type and location, number of scars, age, skin tone, budget, and downtime. That's a physician society recommending its own members, but the underlying point stands: someone needs to assess your scars by type before anything is sold to you.
Several of these treatments are procedures, not facials. Subcision and punch techniques involve cutting under or through the skin. TCA CROSS uses acid at much higher strength than a typical peel. Fillers carry injection risks, and lasers and RF devices can burn. Who may perform each one is set by state law and differs from state to state. Ask who will perform each step, what their license is, and who supervises them. Our guides to checking provider credentials, who can legally inject, and medspa vs. dermatologist vs. plastic surgeon explain how to check.
Questions to ask at a consultation
•Which scar types do you see on my face, and in what areas?
•What will you use for each type, and why?
•How many sessions do you expect, how far apart, and with how much downtime each?
•If you're proposing a filler, is it FDA-approved for acne scars, and how long will it last?
•How many patients with my skin tone have you treated with this device or procedure, and how do you lower PIH risk?
•What improvement is realistic for me, and how will we measure it (for example, with before-and-after photos in the same lighting)?
•Who performs each step, and what is their license?
Be wary of anyone who promises scar "removal," recommends one device for every scar type, or pushes a large prepaid package before mapping your scars. Our unsafe med spa red flags guide lists more warning signs.
This article is educational and does not constitute medical advice. Always consult a licensed medical professional for personalized recommendations.
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