The science of reversing visible skin aging is advancing rapidly. Some of the most exciting developments have come in laser-based technologies. But with so many types available — each using a distinct mechanism, wavelength, and risk profile — it can be difficult to understand which approach is best suited for a given concern.
This article breaks down the main categories of skin rejuvenation therapy: their mechanisms, pros and cons, and the specific signs of aging each targets best. It also covers an emerging fractional technology that has fundamentally transformed how dermatologists approach skin resurfacing — offering results comparable to the most aggressive treatments but with significantly shorter recovery times.
Understanding the science behind each option can help patients have a more informed conversation with their dermatologist or skincare professional before choosing a treatment path.
Table of Contents
Basic Info
Laser skin rejuvenation works by delivering controlled damage to the skin. Areas within the skin absorb laser light and heat up — triggering the body's wound-healing response.
The wound-healing cascade first removes damaged tissue, then drives cells in the skin to produce new collagen and elastin. Both are crucial structural proteins that the body produces less of with age. New collagen production can continue for months after treatment, leading to firmer, more youthful-looking skin.
The process parallels how exercise works at the muscular level — small, controlled amounts of tissue stress lead to stronger, rebuilt tissue. Precise laser energy prompts the skin to rebuild itself in much the same way.
The key is careful control. The goal is to damage specific areas without harming surrounding tissue. Early attempts at using lasers for skin rejuvenation date to the 1980s, but the technology was not yet precise enough, sometimes causing too much damage, scarring, and other adverse effects. Subsequent advances in beam delivery, pulse control, and targeting have made modern laser treatments both considerably safer and significantly more effective than those early devices.
Collagen and elastin are the two structural proteins primarily responsible for skin firmness and elasticity. Collagen provides the scaffolding that keeps skin taut; elastin allows it to stretch and spring back. Both decline with age — and it is this decline that laser treatments aim to counteract by signalling the skin's own repair machinery to produce fresh supplies of each.
Ablative Technologies
Laser technologies for skin rejuvenation fall into two broad categories: ablative and nonablative. Here is how they compare and what each can address.
Ablative laser treatments are the more aggressive category. They remove the top layer of the skin while also stimulating changes at deeper layers.
The first widely used ablative laser was the CO2 laser. Its power gives it strong results potential. Early versions, however, often caused too much damage, leading to scarring. Researchers subsequently developed methods of controlling the laser beam to prevent excessive dwell time and discovered that pulsing the laser on and off — rather than delivering continuous energy — helped substantially.
Modern CO2 lasers are an effective tool for addressing fine lines and wrinkles and for tightening skin. Research has described them as the gold standard in skin rejuvenation technologies [1].
One analysis of 259 patients with fine lines treated with a CO2 laser found an average improvement of 90% [2].
Another common type of ablative laser is the Erbium (Er) laser. Developed in the 1990s, it uses a different wavelength of light that does not penetrate as deeply. It causes less collateral damage to non-targeted tissue, resulting in a shorter recovery period — typically three to eight days — and a lower risk of complications.
Er lasers are well suited to fine lines and superficial skin issues. They may, however, require multiple treatments to achieve results comparable to CO2 lasers. One study found it took at least five passes with an Er laser to match what two to three passes with a CO2 laser could achieve [3].
1. Pros of Ablative Laser Treatments
- Aggressive treatment capable of dramatic results
- Often requires only a single treatment session
2. Cons of Ablative Laser Treatments
- Higher risk of adverse effects
- Longer recovery time
Because the treatment is more aggressive, the risk of adverse effects is correspondingly higher. These can include scarring and unwanted changes in skin pigmentation. Ablative treatments also carry longer recovery times. In rare cases, skin redness following CO2 laser treatment can persist for up to a year [4].
It was precisely these drawbacks that drove researchers to develop less aggressive alternatives — approaches capable of delivering meaningful results without the same side-effect burden.
Nonablative Technologies
Nonablative technologies leave the surface of the skin intact. Rather than removing the outer layer, they penetrate below the surface and heat tissue to promote changes such as increased collagen production. Some work by causing controlled subsurface damage; others stimulate changes by heating tissue without damaging it.
There are many forms of nonablative treatment, each using a distinct technology to produce a unique profile of effects. Below are some of the most widely used.
3. Intense Pulsed Light (IPL)
Intense Pulsed Light (IPL) is, strictly speaking, not a laser treatment. Lasers emit primarily one wavelength of light; IPL uses broad-spectrum light instead. It targets freckles, age spots, and small red veins in the skin — and is particularly effective for sun-induced vascular changes, a common feature of photoaged skin.
A notable advantage of IPL is minimal downtime. Patients can often have the procedure during a lunch break and return to work immediately. There may be mild redness for a few hours to a day, but it is generally well tolerated across a wide range of skin types and tones.
However, multiple sessions are typically required for optimal results — usually three to six treatments spaced several weeks apart. IPL is not well suited to deep wrinkles or significant skin laxity; for those concerns, other modalities are more appropriate.
4. Radiofrequency Devices
For targeting skin wrinkles and laxity, radiofrequency devices are a well-established option. These deliver electrical currents or electromagnetic energy to heat the layers below the skin surface, stimulating collagen production and resulting in tighter, smoother skin. Different devices offer different depths of tissue penetration.
The treatment provides immediate skin tightening through collagen contraction and also stimulates ongoing new collagen formation, with improvement continuing over time. Radiofrequency is suitable for all skin types, and discomfort is generally minimal — making it a widely popular choice for those seeking wrinkle reduction and skin laxity improvement without significant downtime.
5. Infrared Light Devices
Infrared light devices use wavelengths of light that penetrate deep into the skin. The mechanism mirrors that of radiofrequency: thermal energy heats collagen fibres, causing them to contract and stimulating new collagen synthesis.
Like radiofrequency devices, infrared treatments are most effective for skin laxity and fine wrinkles, with minimal recovery time. These devices are not well suited to treating pigmentation or improving the appearance of small blood vessels; their primary application is firming and improving skin texture.
6. Photodynamic Therapy
Photodynamic therapy uses a photosensitising agent applied to the skin, which is then activated by light — often intense pulsed light. This process selectively destroys damaged skin cells and promotes new cell growth, making it effective for both acne and early-stage photoaging. It is best suited to patients with early signs of sun-related skin damage.
7. Red Light Therapy
Red light therapy uses low-intensity red light — typically at wavelengths between 600 and 650 nanometres — to penetrate the skin and stimulate cellular activity.
Unlike traditional laser approaches, red light therapy does not work by heating tissue. Instead, the light is absorbed by mitochondria, stimulating energy production and — theoretically — enhancing processes related to skin appearance, including collagen synthesis, blood circulation, and healing.
Does it work? Multiple randomised controlled trials have found red light therapy to be useful in the treatment of acne [6], [7], which is why clinical guidelines include it as a recommended acne treatment.
For fine lines and wrinkles, the evidence is less settled. A 2022 meta-analysis found the available small trials to be positive in direction, but improvements in skin wrinkles were gradual and effect sizes modest [8].
The Cleveland Clinic's position is that red light therapy remains an emerging treatment generating growing interest, but that there is not yet enough evidence to support most uses [9]. Further research is needed before a stronger recommendation can be made.
8. Pros of Nonablative Technologies
- Lower risk of adverse effects
- Shorter recovery time
9. Cons of Nonablative Technologies
- Generally less powerful than ablative approaches
- Multiple treatment sessions typically required
Overall, nonablative techniques do not typically achieve the same degree of improvement as ablative lasers. For example, one study comparing CO2 laser to intense pulsed light found the CO2 laser produced significantly better wrinkle improvement [10]. Nonablative treatments also usually require several sessions to realise their full potential.
Fractional Technology
Fractional laser technology was developed to combine the effectiveness of ablative treatments with the lower recovery times associated with nonablative approaches.
Rather than treating the entire surface of the skin, fractional lasers treat columns of tissue separated by areas left untreated — treating only a fraction of the skin's surface area at each session. Some tissue is damaged; neighbouring tissue is left intact.
This approach significantly reduces total tissue damage. The undamaged skin adjacent to treated columns accelerates healing and recovery, resulting in fewer adverse effects. Research comparing fractional ablative laser resurfacing to traditional (full-coverage) ablative lasers has found complications to be both less severe and less frequent [11].
Crucially, fractional lasers appear to be nearly as effective as nonfractional lasers in many applications [12], while offering meaningfully shorter recovery times — days rather than weeks for most patients.
Fractional technology is also applied in nonablative lasers, with the same underlying rationale: achieving much of the therapeutic impact of ablative approaches with fewer side effects and a more rapid return to normal activity.
Summary
The landscape of laser and light-based skin rejuvenation covers a wide spectrum of approaches, each with a distinct mechanism, risk profile, and optimal use case. There is no single best option — the right choice depends on the type and severity of aging being addressed, the patient's skin type, their tolerance for recovery time, and practical considerations such as cost and access.
Ablative lasers — CO2 and Er — vaporise the top layer of the skin and heat deeper tissue, stimulating collagen production and skin regeneration. They are the most aggressive treatment type.
Pros:
- Capable of dramatic results
- Often achievable in a single treatment session
Cons:
- Higher risk of adverse effects (scarring, pigmentation changes)
- Longer recovery time
Nonablative technologies — including IPL, radiofrequency, infrared, photodynamic therapy, and red light therapy — preserve the skin's surface while delivering energy to deeper layers. They carry fewer side effects but generally produce more modest results and require multiple sessions.
Finally, fractional lasers come in both ablative and nonablative forms. By treating only a fraction of the skin's surface at each session, they limit adverse effects and recovery time while delivering results comparable to full-coverage nonfractional approaches.
Advantages of Fractional Lasers:
- Reduced risks and adverse effects versus traditional ablative lasers
- Shorter recovery time
- Results comparable to nonfractional approaches in many cases
The best approach depends on the specific signs of aging being addressed, skin type, tolerance for recovery time, and budget. For those seeking dramatic improvement from a single session, an ablative or fractional ablative laser offers the most powerful results. For those prioritising minimal downtime, nonablative options — particularly IPL and radiofrequency devices — offer meaningful improvements with less disruption to daily life. Fractional technology, in both ablative and nonablative forms, represents the current sweet spot for many patients: near-ablative effectiveness at significantly reduced risk and recovery time.
This overview is intended to provide a foundation for an informed conversation with a dermatologist or qualified skincare professional, who can assess individual factors and recommend the most appropriate course of treatment.
References
- https://pmc.ncbi.nlm.nih.gov/articles/PMC10608664/
- https://pubmed.ncbi.nlm.nih.gov/8823015/
- https://pubmed.ncbi.nlm.nih.gov/10206045/
- https://www.uptodate.com/contents/ablative-laser-resurfacing-for-skin-rejuvenation
- https://www.uptodate.com/contents/ablative-laser-resurfacing-for-skin-rejuvenation
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4896818/
- https://dermnetnz.org/topics/lasers-lights-and-acne
- https://onlinelibrary.wiley.com/doi/full/10.1111/phpp.12841
- https://my.clevelandclinic.org/health/articles/22114-red-light-therapy
- https://academic.oup.com/qjmed/article/114/Supplement_1/hcab093.014/6379282
- https://www.uptodate.com/contents/ablative-laser-resurfacing-for-skin-rejuvenation
- https://pmc.ncbi.nlm.nih.gov/articles/PMC3580982/
