CO2 Laser for Acne Scars: How Fractional Resurfacing Improves Skin Texture
Acne can clear and still leave its mark. Long after the breakouts settle, many people are left with pitted, uneven skin that makeup hides for a few hours and no serum seems to fix. Those textural changes are scars, and they sit in the deeper layers of the skin where creams cannot reach. Closing that gap is exactly what fractional CO2 laser resurfacing is built for.
CO2 laser has been a mainstay of scar treatment in dermatology for decades, and the fractional versions used today make it far more practical than the resurfacing lasers of the past. By treating the skin in a controlled pattern rather than all at once, a fractional CO2 laser rebuilds the collagen that acne destroyed while keeping recovery within reach. This article walks through how the technology works, which acne scars it improves, what a session is actually like, and how to think about results and safety.
Key takeaways
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What Are Acne Scars, and Why Do They Form?
Acne scars form when inflammation from a breakout damages the skin and the repair goes slightly wrong. When a pore becomes inflamed and its wall breaks, the body rushes to heal the wound by laying down collagen. Lay down too little, and the surface sinks into a depression. Lay down too much, and the skin pushes up into a raised bump. Either way the result is a lasting change in the skin’s structure rather than a stain that fades on its own.
The risk of scarring climbs with deeper, more inflammatory breakouts, and with the habit of picking or squeezing, which drives inflammation further down. Genetics matter too, since some people heal with more visible scarring than others. Because the damage sits in the dermis, the layer beneath the surface, topical products can improve tone and smoothness a little but cannot lift a scar that has already set.
Dermatologists sort acne scars into two broad families based on what the collagen did during healing.
What Are Atrophic Scars?
Atrophic scars are depressions, the sunken marks most people picture when they think of acne scarring. They form when healing produces too little collagen, so the skin surface drops below the level around it. Atrophic scars make up the large majority of acne scars, and they are the type fractional resurfacing is best known for improving. They fall into three recognized patterns that differ in width and depth, which turns out to matter a great deal when choosing treatment.
What Are Hypertrophic and Keloid Scars?
Hypertrophic scars are raised, firm marks that form when healing lays down too much collagen. They stay within the border of the original blemish and show up most often on the chest and back, where body acne tends to be severe. Keloid scars are a more stubborn version that grows beyond the original wound and can keep expanding. Raised acne scars are far less common than atrophic ones and usually call for a different approach, such as steroid injections or flattening treatments, so the rest of this article centers on the atrophic scars that resurfacing addresses.
What Are the Main Types of Atrophic Acne Scars?
Atrophic acne scars come in three shapes, and telling them apart is the first step in any sensible treatment plan. Most people carry a mix rather than a single type, which is one reason acne scarring is harder to treat than a single brochure procedure suggests.
Scar type | What it looks like | Typical size | How it responds to CO2 resurfacing |
Ice pick | Narrow, pitted marks that look like tiny punctures pressed into the skin | Under about 2 mm wide, running deep into the dermis | The toughest case, since the channel drops below what surface resurfacing reaches, so it is often paired with TCA CROSS or a punch technique |
Boxcar | Round or oval craters with sharp edges and a flat base | About 1.5 to 4 mm wide, shallow to moderately deep | Responds well, especially shallower ones, as the laser blunts the walls and rebuilds collagen under the base |
Rolling | Broad, wavy dips with sloping edges that shift as the skin moves | Around 4 to 5 mm or wider, tethered from below by fibrous bands | Improves with resurfacing, and often better once subcision releases the tethers so the surface can rise |
Why Does Scar Type Change the Treatment Plan?
Depth is the deciding factor. Surface resurfacing works from the top down, so it reaches wide, shallow scars far more easily than a narrow channel that plunges deep into the dermis. A rolling scar tethered from below may barely move until those fibrous bands are released, no matter how much resurfacing the surface receives. A skilled provider reads the mix of scars on your skin and matches each pattern to the method most likely to shift it, which often means combining resurfacing with a second technique.
What Is a Fractional CO2 Laser?
A CO2 laser is a resurfacing laser that emits infrared light at a wavelength of 10,600 nanometers, a wavelength that water absorbs strongly. Skin is mostly water, so when the beam meets the surface, that energy turns to heat and vaporizes a precise layer of tissue. Dermatologists have used the effect to resurface scarred and sun-damaged skin since the 1990s.
The word fractional describes how the energy reaches the skin. Rather than treating the whole surface in one continuous sweep, a fractional laser splits its beam into many tiny points, so it treats a fraction of the skin and leaves healthy tissue standing in between. That shift, introduced in the mid-2000s, is what made deep resurfacing practical for everyday patients.
How Does Fractional Photothermolysis Work?
The principle behind fractional lasers is called fractional photothermolysis. Each microbeam drills a microscopic column of controlled damage, known as a microthermal treatment zone, straight down into the skin. Around every column, a ring of untouched tissue stays intact and full of the cells and blood supply that repair depends on. Because those islands of healthy skin surround each treated zone, the surface closes over the wounds quickly, often within days rather than the weeks that full-field CO2 resurfacing once demanded.
That preserved tissue is the safety margin that lets a CO2 laser reach depth without leaving an open wound across the whole face. It also lowers the chance of the serious complications that gave early aggressive resurfacing its reputation.
How Does CO2 Laser Improve Acne Scar Texture?
The improvement happens in two stages. First the laser ablates, or vaporizes, the damaged tissue at the surface and along the scar, which softens sharp edges and clears out some of the old, disorganized collagen right away. Then the heat left in the surrounding skin sets off a wound-healing cascade that rebuilds the deeper structure over the following months.
That second stage is where most of the real change comes from. The controlled heat prompts fibroblasts, the cells that produce collagen, to switch on and lay down fresh collagen and elastin in an organized pattern. Researchers tracing the process have linked it to shifts in signaling molecules such as matrix metalloproteinases and transforming growth factor beta, which clear out old collagen and guide new fibers into place. As that new collagen matures and contracts, the floor of a scar lifts and the texture around it evens out.
Backed by research In pooled clinical data, roughly 70 percent of people treated with ablative fractional CO2 laser achieved more than 25 percent improvement in their acne scarring, and a substantial share improved by more than half over a full course of sessions. Gains of that kind are why fractional CO2 has stayed a frontline option for scars the surface cannot smooth on its own. |
Because the collagen rebuild is gradual, the skin keeps refining for months after the visible healing is done. The texture you see at six months is usually smoother than what you saw at six weeks.
Which Acne Scars Respond Best to CO2 Resurfacing?
Fractional CO2 laser earns its reputation on the wider, shallower atrophic scars. Boxcar scars, with their defined edges and flat base, soften as the laser blunts the walls and stimulates collagen under the base. Rolling scars improve as well, especially once any tethering beneath them is addressed so the surface can rise. Broad zones of rough, uneven texture from years of breakouts also respond, since resurfacing is well suited to blending large areas.
Deep ice pick scars are the harder case. Their narrow, steep channels run further down than surface resurfacing comfortably treats, so laser alone often makes only a modest difference. For these, many providers reach for a targeted method first. TCA CROSS places a tiny amount of trichloroacetic acid at the base of the scar to remodel it from the bottom, while a punch technique removes the scar outright. Resurfacing then blends the surrounding skin once that deep work is done.
This is why a combination plan usually beats any single tool. A provider might release rolling scars with subcision, treat ice pick scars point by point, then pass the fractional CO2 laser over the whole area to smooth everything into a more even surface.
What Does a CO2 Laser Treatment Involve?
How Should You Prepare?
Preparation starts weeks before the session. Your provider reviews your history, asks about any tendency to cold sores or pigment changes, and may start you on a skin-prep routine to steady the skin beforehand. Sun exposure is paused in the run-up, because tanned or sunburned skin raises the risk of pigment problems afterward. Anyone prone to cold sores is often given an antiviral as a precaution.
What Happens During the Session?
On the day, the skin is cleansed and a topical numbing cream goes on, usually for thirty to sixty minutes, so the treatment stays comfortable. For deeper work, extra measures can be added. The provider then passes the handpiece over the area while a scanner lays the microbeams in an even grid at the depth and density chosen for your skin. A full face often takes somewhere between twenty minutes and an hour. Most people describe the sensation as heat with a prickling that the numbing keeps manageable, along with the occasional feeling of warm air from the device.
What Is Recovery Like?
Right afterward the skin looks red and feels hot, close to a strong sunburn, and it may swell a little for a day or two. Over the next several days it turns rougher, then flakes and peels as the fresh surface comes through. How long this lasts depends on how deep the treatment went, from a couple of days after a light session to as much as two weeks after an aggressive one. Aftercare centers on gentle cleansing, generous moisturizing, and strict sun protection while the new skin is fragile. The one thing to avoid is picking at the flaking skin, since that can invite infection or a fresh mark.
How Many Sessions Does It Take, and When Do Results Appear?
Most people need a series rather than a single visit, though the number shifts with scar depth and the intensity used. Lighter, more comfortable sessions are usually spaced several weeks apart and repeated a handful of times, while a single deep session accomplishes more at the cost of a longer recovery. Providers often stage treatment so the skin fully settles between visits.
Results arrive on two timelines. The first is quick: once the peeling finishes, the skin looks brighter and feels smoother within a week or two. The second is slower and more meaningful, as new collagen keeps building and reorganizing for six months to a year after the last session. Full remodeling of a scar’s structure genuinely takes that long, which is why patience serves you better than judging the outcome at the three-week mark.
Is CO2 Laser Safe for All Skin Tones?
CO2 laser can be used across a wide range of skin tones, but the approach has to change with the skin. The main concern in richer, more melanin-heavy complexions is post-inflammatory hyperpigmentation, a temporary darkening that can follow the controlled injury of resurfacing. It usually fades over weeks to months, and careful technique lowers the odds of it appearing at all.
Experienced providers manage that risk by choosing gentler settings, spacing sessions further apart, sometimes running a small test area first, and pairing treatment with a pigment-calming skincare plan before and after. For some patients with deeper skin tones, a provider may steer toward a device that heats the dermis without breaking the surface, such as radiofrequency microneedling, which carries a lower pigment risk. An honest consultation is where that call gets made.
A note on expectations Fractional CO2 laser improves the look and feel of acne scars, and for many people the change is substantial. Complete erasure is rare, though, and any provider promising perfectly smooth skin in one visit is overselling it. Realistic goals, set with a qualified professional who has examined your skin in person, lead to the happiest outcomes. |
How Does CO2 Laser Compare to Other Acne Scar Treatments?
CO2 laser sits at the stronger end of the resurfacing spectrum, which is both its advantage and its trade-off. For deep textural change it is hard to beat, but it asks for real downtime in return. Several other treatments occupy the gentler end of that range.
Microneedling creates fine channels with tiny needles to prompt collagen, with less downtime and a milder result that suits early or shallow scarring, offered here as microneedling with PRP in Tinton Falls. Radiofrequency microneedling goes deeper by sending heat through those needles into the dermis, firming from within while sparing the surface, which is part of why it carries a lower pigment risk for darker skin. Morpheus8 RF microneedling in Tinton Falls is one example. Chemical peels work on the surface to lift tone and shallow texture and make a useful maintenance step, and you can read more about chemical peels in Tinton Falls. For a controlled, adjustable CO2 option, Solaria CO2 laser resurfacing in Tinton Falls lets a provider set the depth to match your scars and your schedule.
No single option wins for everyone. The right choice depends on your scar types and skin tone, and on how much recovery time you can spare, which is exactly what a consultation sorts out.
Can You Combine CO2 Laser with Other Treatments?
Combination plans are common, because most people have more than one kind of scar. A provider might release tethered rolling scars with subcision, treat stubborn ice pick scars with TCA CROSS, then finish with fractional CO2 to smooth the whole area into a single even surface. Sequencing and spacing matter here, so this is work for an experienced hand.
Some clinics also pair resurfacing with platelet-rich plasma, drawn from your own blood and applied to the treated skin to support healing and add growth factors during recovery. If that interests you, PRP and PRF treatments are one way it is offered locally. The aim of any combination is the same: match each technique to the scar it treats best, rather than asking one device to do everything.
How Do You Protect Your Results and Avoid Complications?
Most of what makes a CO2 result last happens away from the laser. Sun is the biggest threat, both to healing skin and to the collagen you paid to build, so daily protection is not optional. A couple of habits carry most of the weight:
Keep the healing skin clean and well moisturized, and leave the flaking alone so it can shed on its own
Use broad-spectrum sunscreen every day, stay out of direct sun while the skin recovers, and keep protecting it long after
Beyond aftercare, the single biggest factor is who holds the handpiece. CO2 resurfacing rewards judgment, since the same laser that renews skin can overtreat it in careless hands. A provider who examines your skin in person, explains the plan in plain terms, and sets honest expectations is worth more than any device specification on a page.
The Bottom Line?
Acne scars are stubborn because they live in the deeper structure of the skin, and fractional CO2 laser works because it reaches that structure and rebuilds it. For boxcar scars, rolling scars, and broad rough texture, a course of resurfacing can smooth and firm skin in a way topical care cannot match, especially when it is paired with the right procedure for any deep ice pick scars. Results build over months, downtime scales with depth, and skin tone shapes the plan, so the treatment rewards a thoughtful provider and a patient timeline.
If acne scarring has worn on your confidence, the practical next step is an in-person assessment, where a professional can map your scar types and lay out a realistic plan.
Considering CO2 laser for acne scars? The team at Ageless Affairs Med Spa in Tinton Falls, New Jersey can assess your skin and talk through your options in person. Book a consultation to get started. |
References
1. An Overview of the Mechanisms of Fractional CO2 Laser in Scar Treatment. Lasers in Medical Science, 2026. https://link.springer.com/article/10.1007/s10103-026-04846-z
2. The Use of a Fractional Laser in Acne Scar Treatment: A Systematic Review. Life (Basel), 2025. https://doi.org/10.3390/life15060915
3. Comparative Effectiveness and Safety of Fractional Laser and Fractional Radiofrequency for Atrophic Acne Scars. Life (Basel), 2025. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12471114/
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