Blog > Pigmentation > Fractional Erbium Laser Vs CO2 Laser: Which is better?

Fractional Erbium Laser Vs CO2 Laser: Which is better?

With each passing year, as age begins to catch up, it is perfectly normal to begin taking an interest in skin rejuvenation and skin resurfacing treatment options. Laser resurfacing technologies represent an exciting development to improve tone, texture and pigmentation of the skin. Of these, Fractional Carbon dioxide (CO2) laser and Fractional Erbium laser are both commonly used for skin rejuvenation and resurfacing.

Although both of these ablative laser-based treatments are effective in resolving issues pertaining to skin textures, they differ from each other in some aspects including treatment mechanism, depth of treatment, and properties. 

In this article, we will discuss the differences between the fractional Erbium laser (Erbium: YAG laser) and the CO2 laser as well as its effectiveness on different skin conditions.

Read on to find out why we don’t use CO2 lasers for the treatment of acne scars!*

Ablative Laser Resurfacing

Although Erbium: YAG laser and Fractional CO2 lasers are both classified as ablative lasers, they have different properties. But before we dive into their differences, let’s first understand what ablative lasers are.

Ablative laser skin resurfacing involves the selective thermolysis of the epidermal and superficial dermal layers of the skin by targeting them with light energy, leading to better skin quality and tone. During the procedure, water in the skin cells absorb light energy from the laser emitting  thermal energy, which destroys the surrounding tissue [1].

Ablative lasers vaporize tissue and therefore are more aggressive compared with the gentler non-ablative lasers that leave the skin intact. Although ablative lasers result in far more downtime and a lengthier recovery process, they remain the lasers that produce the most dramatic skin resurfacing outcomes. Non-ablative lasers are free of the side effects of ablative lasers and leaves the epidermis intact while producing rejuvenating skin effects. By comparison, the treatments are gentle and requite less downtime, but produce a more moderate response [2].


Although Erbium: YAG laser and Fractional CO2 lasers are both classified as ablative lasers, they have different properties. But before we dive into their differences, let’s first understand what ablative lasers are.

Fractional Erbium Laser and CO2 Laser: What’s the Difference?

CO2 lasers was once a major advancement in the area of facial skin resurfacing and has been used with great success for the treatment of wrinkles, photoaging, scarring as well as pigmentation. However, problems with prolonged healing, prolonged redness, risks of hyperpigmentation and hypopigmentation has led to the development of the Erbium:YAG Laser.

Additionally, the higher incidence of post inflammatory hyperpigmentation following a CO2 laser treatment in darker skin types is a major disadvantage of the CO2 laser over the Erbium:YAG Laser.

When laser energy interacts with tissue, there are four possible outcomes: (1) absorption, (2) scatter, (3) reflection, and (4) transmission. The amount of each depends to a large part on the wavelength of the laser energy and chromophore of the tissue [3].

CO2 Laser

CO2 laser:  CO2 lasers has a wavelength of 10,600 nm and is very well absorbed by water [4]. Despite the longer wavelength that allows deeper penetration, the light energy absorbed is converted into heat energy, which rapidly heats the tissue. This heat has several effects that causes thermal damage in adjacent and deeper tissues, and this thermal damage is thought to account for the delayed healing, prolonged redness and pigmentation problems associated to CO2 lasers. 

Collagen, a large component of the dermis does not absorb CO2 laser very well. This then leads to more heat build-up and adjacent thermal damage, which in turn, acts as a barrier to further penetration of the laser with subsequent passes. This has been termed the “stacking effect”. However, the CO2 laser also causes contraction in the collagen, which is thought to account for further remodeling and increased collagen production. These effects results in skin tightening.

One other advantage of the CO2 laser is the ability to coagulate the blood vessels when removing deep dermal lesions, like moles, leading to less bleeding.


Erbium laser

In contrast, the Erbium: YAG laser has a wavelength of 2,940 nm. This is 10 to 20 times better absorbed by water and human skin than the CO2 laser and was developed for this reason [5]. The better absorption means less heat loss and therefore less thermal damage to adjacent surfaces, allowing faster recovery times, less redness and a significantly decreased risk of hyperpigmentation and hypopigmentation. The Erbium: YAG laser is also well absorbed by collagen as compared to the CO2 laser.

However, the disadvantages of the minimal thermal damage of the Erbium: YAG laser is that it does not penetrate as deeply into the tissues as the CO2 laser. It may take three or more passes to fully ablate the epidermis. That said, it does have the benefit of allowing gentler, more specific removal of superficial pigments, but it does make the removal of pigmentation in deeper tissues more time consuming.

Although wound contraction secondary to tissue healing may result in nearly the same tissue tightening as heat-induced collagen contraction, the two processes are very different and variable, with increased risk of scarring seen with wound contracture, compared with heat-induced collagen tightening [6].

Laser Pigmentation

Erbium versus CO2 Laser: Which is more effective?

#1 Treatments on Wrinkles/Fine lines

Studies have shown that CO2 lasers cause immediate contraction of the ablated areas by denaturing existing old collagen [7]. This stimulates new collagen, and collagen content continues to increase well after the procedure. As a result, CO2 lasers work best at alleviating fine wrinkles.

That said, similar results can be derived from the Erbium: YAG laser by passing it multiple times over the treatment zone. It also provides a more precise ablation of the skin with even less damage to the surrounding tissue.

#2 Treatments on Acne Scars

In the treatment of acne scars, however, the effects of fractional CO2 cannot be reproduced with Erbium: YAG lasers due to its deeper penetration. Studies have shown that CO2 lasers produced more significant results in textural issues like acne scars in comparison to Erbium: YAG lasers. However, it is also reported that despite CO2 lasers having superior results, the Erbium: YAG laser is better tolerated with less downtime in acne scar patients [8].

Apart from the risks of hyperpigmentation and hypopigmentation, post-procedure discomfort was slightly more pronounced after the Erbium: YAG treatment in the first few days, but later on there were more complaints following the CO2 laser treatment [9].


#3 Laser resurfacing for skin rejuvenation 

Er: YAG lasers can be used with great precision to control the thermal damage inflicted during the procedure. Therefore, it is possible to tailor the treatment protocols based on individual patient conditions. This ability to control thermal damage also allows the practitioner to use more superficial treatments with almost no downtime, and much less risk of PIH.  

Subject to the style and speed of the treatment, Er: YAG laser treatments can be fine-tuned for increasing or decreasing the heat delivered to the skin with decreased thermal tissue effects.

What are the Side Effects of Erbium: YAG laser and CO2 laser?

CO2 Laser Side Effects: 

Some of these include [10]:

  • Post inflammatory Hyperpigmentation (PIH)
  • Infection
  • Delay in wound healing
  • Scarring
  • Skin peeling
  • Skin redness
  • Milia - small, yellow or white cysts that appear in clusters
  • Hypopigmentation

With this in mind, people should always discuss any potential side effects with the healthcare professional providing the treatment. The skin typically requires 2 to 4 weeks to completely heal from CO2 laser treatment. New skin begins to grow after around 2 weeks following laser treatment.

The skin will initially be quite raw and may have drainage immediately after laser treatment. It may also look and feel as if it is severely sunburned.

Erbium:YAG Laser Side Effects: 

Some of these include [11]:

  • Mild erythema 
  • Burning sensation
  • Itching
  • Post inflammatory Hyperpigmentation (PIH)

Other possible complications include the appearance of acne, milia and dermatitis in the treated region. Erbium:YAG lasers also require a shorter recovery time compared to CO2 lasers because of the shallow depths of wounds they create. Furthermore, Erbium:YAG lasers deliver reduced thermal damage to the surrounding skin tissue, which allows for much faster healing compared to deeper injuries and extensive thermal damage that CO2 lasers produce.

Although Erbium:YAG lasers do not penetrate as deeply as CO2 lasers, they’re able to mimic the effects of CO2 lasers by multiple passes, stacking and increasing the pulse duration while limiting the risk of unwanted side effects. The flexibility of an Erbium:YAG laser’s pulse formats and energy capabilities make it a desirable and safer alternative to the older CO2 laser for ablative and fractional treatments.

Why we don’t use CO2 lasers for acne scars or skin rejuvenation

Compared to Caucasians, Asian skin tend to be more vulnerable to post-inflammatory hyperpigmentation. As mentioned above, studies have also observed that CO2 laser treatment patients are exposed to a significantly higher risk of hyperpigmentation and hypopigmentation.

Hyperpigmentation and hypopigmentation are primarily a fallout of thermal damage. Since Asian skin has a greater tendency to capture heat, the occurrence of PIH is more common in dark skin types corresponding to Type III and above on the Fitzpatrick scale [12].

If used on Asian skin, complications of hyperpigmentation and burns more often occur, resulting in multiple additional treatments to rectify the damage. With deep scars, the results are often unsatisfactory due to more complications and longer downtime for patients.

Instead of using the CO2 laser, at Ensoul Clinic, we prefer to use Erbium: YAG lasers as well as the ablative radiofrequency technology which are more suitable for Asian skin. The newer Erbium:YAG can reach the necessary ablative depth to treat deep scar tissue that is pulling the skin down. Dermal lasers are also used to stimulate the collagen production.

This triple-action of deep fractional skin resurfacing, which releases the tethering scar fibers and rebuilds the skin’s collagen matrix, means the skin is restored to its natural position, resulting in much smoother skin a much lower risk of the side effects associated to CO2 lasers.


Which is more suitable for me: Erbium Laser or CO2 laser?

Each laser is better suited for different skin types and concerns, so the best way to know which laser is best for you should be based on a professional evaluation, not the brand of laser. Research and consult with an experienced physician to learn more about your skin condition and explore your treatment options. Here are some questions to help you choose the best medical aesthetic clinic for your skin concerns.