Several professional treatments can meaningfully improve acne scars, but the right one depends almost entirely on the type of scar you have. Treatments like subcision, chemical reconstruction, fractional lasers, microneedling, and dermal fillers each target different scar structures and work through different mechanisms. No single procedure erases all scar types equally, which is why dermatologists increasingly combine techniques tailored to individual scar patterns rather than relying on one approach.
Why Acne Leaves Permanent Scars
When acne is severe or inflamed enough, it damages not just the skin’s surface but the deeper structural tissue underneath. Inflammatory acne triggers a cascade of immune activity: immune cells flood the area, and the body ramps up production of enzymes that break down collagen, the protein scaffolding that gives skin its structure. Research shows that key inflammatory molecules become activated in acne lesions, driving both the inflammation itself and the degradation of collagen in the surrounding tissue.1PubMed Central. Inflammation and extracellular matrix degradation mediated by activated transcription factors nuclear factor-kappaB and activator protein-1 in inflammatory acne lesions in vivo When the body tries to repair that damage, the new tissue it lays down is often disorganized. Elastic fibers and collagen fibers degrade drastically and recover only partially, leaving behind a depression or, less commonly, a raised bump where the wound healed with too much scar tissue.2PubMed. Atrophic acne scar: a process from altered metabolism of elastic fibres and collagen fibres based on transforming growth factor-β1 signalling
Scar Types and Why They Matter for Choosing Treatment
Acne scars fall into two broad camps: depressed (atrophic) and raised (hypertrophic or keloidal). The depressed scars are far more common and are further divided into three shapes that respond differently to treatment.
- Ice pick: Narrow, deep, V-shaped pits that extend into the dermis. They look like someone poked the skin with a sharp instrument. Because they are so deep and narrow, they are the hardest to improve with surface-level treatments.
- Boxcar: Wider depressions with sharply defined vertical edges, like a small crater. These respond more readily to resurfacing techniques.
- Rolling: Broad, shallow undulations caused by fibrous bands pulling the skin down from underneath. The skin looks wavy rather than pitted.
Raised scars form when the healing process overshoots. Hypertrophic scars stay within the original wound boundary, while keloids grow beyond it, with keloids involving deeper fibrosis.3PubMed Central. Current Advances in Hypertrophic Scar and Keloid Management4Burns & Trauma. Acne-induced pathological scars: pathophysiology and current treatments Raised scars call for entirely different treatments, typically corticosteroid injections, silicone sheeting, or sometimes surgical revision, and are not addressed by the resurfacing procedures covered below.
TCA CROSS for Ice Pick Scars
Ice pick scars are notoriously stubborn. Lasers and microneedling treat the surface well but struggle to reach the narrow base of an ice pick. The most targeted option is a technique called CROSS (Chemical Reconstruction of Skin Scars), which involves applying a high concentration of trichloroacetic acid (TCA) directly into the pit using a toothpick-sized applicator. The acid destroys the scarred tissue at the bottom, and as the wound heals, new collagen fills the depression from below.
The results are well supported. In one study evaluating 100% TCA CROSS on ice pick scars, eight out of ten patients saw more than 70% improvement, and the remaining two showed 50 to 70% improvement with no significant side effects.5PubMed Central. An Assessment of the Efficacy and Safety of CROSS Technique with 100% TCA in the Management of Ice Pick Acne Scars A separate study in patients with darker skin tones found similarly strong outcomes: roughly three-quarters of patients achieved excellent improvement after four sessions.6PubMed. Evaluation of CROSS technique with 100% TCA in the management of ice pick acne scars in darker skin types The technique is cost-effective and relatively simple, which makes it a practical first-line option when ice pick scars dominate the picture. Research comparing 70% and 100% TCA concentrations found that 100% TCA was significantly more effective on ice pick scars than on boxcar scars, reinforcing that this is really an ice-pick-specific tool.7PubMed. Comparison of 70% and 100% concentration of trichloroacetic acid peeling efficacy with chemical reconstruction of skin scars technique in atrophic acne scar treatment
Subcision for Rolling Scars
Rolling scars have a unique structural problem: fibrous bands tether the skin’s surface to deeper tissue, creating that wavy contour. Subcision addresses this directly. A needle or small cannula is inserted under the scar to physically cut those tethering bands, freeing the skin surface so it can lift. The controlled injury also triggers new connective tissue growth that fills the space underneath.8PubMed Central. Subcision for Atrophic Acne Scarring: A Comprehensive Review of Surgical Instruments and Combinatorial Treatments
Subcision is especially effective for rolling scars because it targets their specific cause. It can be performed with a standard needle, a specialized cannula, or even a blunt-tipped instrument depending on scar depth. The procedure often produces bruising that lasts a week or so. Multiple sessions spaced several weeks apart usually give the best results, and subcision is frequently paired with other treatments like fillers or microneedling to boost the overall outcome.
Fractional Lasers
Fractional lasers work by creating thousands of tiny columns of controlled damage in the skin, leaving surrounding tissue intact to speed healing. The body responds by producing fresh collagen to repair the treated zones, which gradually smooths out depressed scars over weeks to months.
There are two main categories. Ablative fractional lasers (typically CO2 or erbium) vaporize tissue and produce more dramatic collagen remodeling, but they come with longer downtime, redness, and swelling that can last a week or more. Non-ablative fractional lasers heat the tissue without removing it, causing less downtime but requiring more sessions for comparable results. A head-to-head trial comparing a picosecond laser with a non-ablative fractional laser found that the picosecond device produced significantly better improvement for both narrow V-shaped and wider U-shaped acne scars, with measurably flatter skin on three-dimensional imaging. Patients in the picosecond group also reported higher satisfaction with both pore appearance and scar improvement.9PubMed Central. Comparison of fractionated frequency-doubled 1,064/532 nm picosecond Nd:YAG lasers and non-ablative fractional 1,540 nm Er: glass in the treatment of facial atrophic scars: a randomized, split-face, double-blind trial
Picosecond lasers are a newer entrant in the field. They deliver ultra-short pulses of energy that create microscopic zones of disruption in the dermis, stimulating collagen without significant surface damage. One clinical study using a fractional 1,064-nm picosecond laser found progressive improvement in acne scars measured at three, six, and fourteen weeks after treatment.10PubMed Central. Efficacy and Safety of Treatment with Fractional 1,064-nm Picosecond Laser with Diffractive Optic Element for Wrinkles and Acne Scars: A Clinical Study Another study of fractional picosecond treatment on atrophic scars showed that over 90% of patients were rated as improved by both physicians and patients themselves, with significant reductions in scar color, texture irregularity, and distortion.11PubMed Central. Fractional picosecond laser treatment of non‐acne atrophic scars and scar erythema in Chinese patients
One important consideration with lasers: scar type matters. A study of non-ablative fractional laser on all three atrophic scar types found that boxcar scars responded best (about 53% improvement), followed by rolling scars (about 43%) and ice pick scars (about 26%).12PubMed. Which type of atrophic acne scar (ice-pick, boxcar, or rolling) responds to nonablative fractional laser therapy? If ice pick scars are your primary concern, laser treatment alone may not be enough, and TCA CROSS or punch excision would be better first steps.
Microneedling and Radiofrequency Microneedling
Standard microneedling uses a device covered in fine needles to create hundreds of tiny punctures in the skin. This controlled injury triggers the wound-healing cascade, resulting in new collagen production. Skin biopsies taken after microneedling sessions showed significant increases in collagen types I, III, and VII, with clinical improvement visible within months.13PubMed Central. Microneedling Therapy for Atrophic Acne Scars: An Objective Evaluation Another study documented roughly a 31% reduction in skin surface irregularity after three sessions, measured across different skin tones.14PubMed. Percutaneous collagen induction: an effective and safe treatment for post-acne scarring in different skin phototypes
Radiofrequency (RF) microneedling adds another layer. The needles deliver radiofrequency energy into the dermis, generating heat that causes additional collagen tightening and remodeling beyond what needling alone achieves. Research demonstrates that RF microneedling increases the expression of growth factors associated with collagen production while simultaneously reducing inflammatory signals.15PubMed. Comparison of fractional microneedling radiofrequency and bipolar radiofrequency on acne and acne scar and investigation of mechanism: comparative randomized controlled clinical trial It also has a well-documented effect on improving the thickness and quality of dermal connective tissue, with new collagen formation continuing for up to three months after treatment.16Aesthetic Surgery Journal. The Role of Fractional Radiofrequency in Long-term Acne Remission and Reduction of Acne Scar Load
Microneedling has a clear practical advantage: it works across all skin tones with a lower risk of post-treatment pigment changes compared to ablative lasers. It is also less expensive per session than most laser treatments, making it a reasonable entry point if you are new to professional scar treatment.
Dermal Fillers
Fillers take a fundamentally different approach. Instead of stimulating your skin to rebuild itself, they physically fill in the depression. A systematic review of 24 studies evaluating injectable fillers for atrophic acne scars found that all filler types studied, including hyaluronic acid, collagen-based, collagen-stimulating, autologous fat, and decellularized matrix fillers, produced significant scar improvement.17PubMed Central. Injectable Fillers for Atrophic Acne Scars: A Systematic Review of Mechanisms, Evidence, and Clinical Algorithms
The appeal of fillers is immediate visible improvement, sometimes right on the treatment table. Hyaluronic acid fillers are temporary, lasting roughly six to twelve months before the body absorbs them. Collagen-stimulating fillers like poly-L-lactic acid work differently: they gradually prompt your own tissue to produce collagen around the injected particles, and their effects can last two years or more. Fillers are best suited for broader, shallower depressions like boxcar and rolling scars. They are not ideal for narrow ice pick scars, where the opening is too small for effective injection.
Why Combination Treatments Outperform Single Approaches
Most people have a mix of scar types, which is precisely why combining treatments tends to produce better results than any single modality. A case series evaluating a triple-therapy approach (TCA CROSS for focal scars, subcision to release tethering, and microneedling to stimulate broad-area collagen remodeling) found consistently high patient satisfaction with photographic evidence of improvement across various skin types.18PubMed Central. A Combination Approach to Treating Acne Scars in All Skin Types: Carbolic Chemical Reconstruction of Skin Scars, Blunt Bi-level Cannula Subcision, and Microneedling-A Case Series Each component addresses a different structural problem: CROSS rebuilds the base of narrow pits, subcision releases the tethering that creates surface undulation, and microneedling smooths overall texture.
Platelet-rich plasma (PRP), prepared by concentrating growth factors from your own blood, is sometimes added as an adjunct to subcision or microneedling. A comparative study found that patients who received PRP alongside subcision and microneedling saw greater improvement in scar grading than those who had the procedures alone, with 30% of PRP patients improving from severe to mild scars compared to 15% in the control group.19Journal of Cutaneous and Aesthetic Surgery. PRP and its benefit as an adjunctive therapy with subcision and microneedling in atrophic scars: a comparative study A broader literature review concluded that PRP can improve wound healing and early scar quality, and may contribute to better texture, color, and contour when incorporated into resurfacing protocols.20PubMed Central. The evidence behind the use of platelet-rich plasma (PRP) in scar management: a literature review
Considerations for Darker Skin Tones
If you have medium to deep skin, the biggest treatment risk is not that the procedure will fail but that it will leave you with new discoloration. Post-inflammatory hyperpigmentation, those dark spots left behind by inflammation, is far more common in darker skin. A study of non-ablative fractional laser in patients with Fitzpatrick skin types IV through VI found that temporary hyperpigmentation was a common side effect, especially at higher energy settings.21Dermatologic Surgery. Nonablative Fractional Laser Resurfacing for Acne Scarring in Patients With Fitzpatrick Skin Phototypes IV-VI
That said, newer devices and more conservative settings are narrowing the gap. A recent study testing a novel 1550-nm non-ablative laser across all Fitzpatrick skin types found no statistically significant differences in treatment outcomes or adverse event rates between lighter and darker skin groups, with minimal adverse events overall in the darker skin subgroup.22PubMed Central. Treating Acne Scars in Fitzpatrick Skin Types I–VI Using a Novel 1550 nm Non‐Ablative Resurfacing Laser With Focal Point Technology The key is lower energy density, more sessions, and a provider experienced in treating skin of color. Microneedling and RF microneedling remain safe options across skin tones because they do not rely on light absorption and therefore carry minimal pigmentation risk.
What Topical Products Can and Cannot Do
You will find no shortage of serums and creams marketed for acne scars. Most of them cannot meaningfully change a true depressed scar, because the damage sits deep in the dermis where topical products barely penetrate. The exception worth noting is topical retinoids. Evidence indicates that retinoids have a well-established role in improving the appearance of atrophic acne scars, reducing the progression of scarring, and supporting skin remodeling over time.23PubMed Central. Topical Retinoids in Acne Vulgaris and Acne Scars-From Monotherapy to Combining Regimens They are not going to erase a deep ice pick, but for mild scarring they can make a noticeable difference, and they serve as a useful add-on to procedural treatments.
Daily sunscreen is the single most impactful “treatment” many people overlook. UV exposure darkens post-inflammatory pigmentation and can slow collagen remodeling after procedures. Consistent broad-spectrum sunscreen use, SPF 30 or higher, applied daily, protects your results and prevents new discoloration from forming.
Preventing Scars Before They Form
The most effective scar treatment is preventing the scar in the first place, and there is solid evidence that early, aggressive acne treatment can reduce scarring. A six-month randomized trial of adapalene 0.3% combined with benzoyl peroxide 2.5% gel found that the treatment side of the face had about 15% fewer scars than baseline, while the untreated control side actually gained about 14% more scars, a difference of roughly 30 percentage points. Inflammatory lesions dropped by about 87% on the treated side.24PubMed Central. Prevention and Reduction of Atrophic Acne Scars with Adapalene 0.3%/Benzoyl Peroxide 2.5% Gel in Subjects with Moderate or Severe Facial Acne: Results of a 6-Month Randomized, Vehicle-Controlled Trial Using Intra-Individual Comparison A separate retrospective study of over 400 participants found that adapalene gel was protective against acne scarring, while papular acne and isotretinoin use were associated with a higher risk of complications, likely because isotretinoin is prescribed for the most severe cases, where scarring has already begun.25Dove Press / Dove Medical Press (Clin Cosmet Investig Dermatol). The Predictive Factors of Acne Scarring and Post-Inflammatory Hyperpigmentation: A Retrospective Cohort Study
The practical takeaway: if your acne is inflammatory and persistent, do not wait it out hoping it will resolve on its own. See a dermatologist early. Every inflamed lesion that heals with scarring is adding to a cumulative burden that is far harder to reverse than to prevent.
Setting Realistic Expectations for Results
Scar treatment is a process measured in months, not days. Collagen remodeling after procedures like microneedling or laser treatment continues for roughly three to six months after each session. You will typically not see the full result of a given treatment until well after your final session. Most treatment plans involve three to six sessions spaced four to eight weeks apart, and some people pursue additional rounds if they want further refinement.
The honest framing is that most treatments produce improvement, not elimination. A 30 to 60% improvement in scar depth and texture is a realistic range for most procedures, and that degree of change is often enough to meaningfully change how scars look in normal lighting and conversation distance. Deeper or more extensive scarring may require several different modalities staged over the course of a year or more.
The Emotional Weight of Acne Scars
Acne scars carry a psychological burden that often gets underestimated. A multi-country survey of people with facial atrophic acne scars found that about 75% worried their scars would never go away, and 68% reported feeling self-conscious. Roughly 17% of participants showed clinical features of body dysmorphia, with the rate climbing as scar severity increased.26PubMed Central. Impact of Facial Atrophic Acne Scars on Quality of Life: A Multi-country Population-Based Survey Quality-of-life scores worsened steadily with scar severity, and among those with severe scarring, about a third described the impact as “very large” or “extremely large.” These numbers matter because they explain why many people are willing to invest substantial time and money in treatment even when complete scar elimination is not possible. Incremental improvement can be genuinely transformative for daily confidence and wellbeing.