Thulium & Erbium Lasers in Skin of Colour - What 15 Clinical Studies Reveal
Pure Tone Journal · Clinical Evidence
Thulium & Erbium Lasers in Skin of Colour - What 15 Clinical Studies Reveal
A scientific review published in February 2026 examined the effectiveness and safety of 1550nm Erbium Glass and 1927nm Thulium fractional laser treatments in patients with darker skin tones.
The findings are encouraging, particularly for acne scarring, pigmentation and photoageing. They also highlight something every practitioner should understand - treatment settings, patient selection and the risk of post-inflammatory hyperpigmentation matter.
We take a closer look at what the researchers found, where the evidence is strongest and what it means for clinics considering dual-wavelength fractional laser technology.
Published February 2026
A Closer Look at 15 Clinical Studies
The review examined existing clinical evidence for two established fractional laser wavelengths in patients with skin of colour.
The paper, titled “Dual 1550-nm Erbium Glass Fiber and 1927-nm Thulium Fiber Non-ablative Fractional Laser System Treatment in Patients With Skin of Color: A Review of Clinical Studies and Unmet Needs”, was published in Lasers in Surgery and Medicine on 10 February 2026.
Written by Mitchel P. Goldman and colleagues, the review brought together findings from 15 clinical studies involving patients with Fitzpatrick skin types III–VI.
These skin types are particularly relevant when considering laser skin rejuvenation because pigmentation responses and the risk of post-inflammatory hyperpigmentation can influence treatment planning.
The authors examined clinical improvements, adverse effects and the available evidence supporting the use of 1550nm Erbium Glass and 1927nm Thulium laser wavelengths.
What Was the Main Conclusion?
The researchers concluded that the evidence supports the use of these non-ablative fractional laser technologies in selected patients with skin of colour, while emphasising that appropriate treatment settings and aftercare are essential to minimise complications.
They also identified important gaps in the available research, particularly for Fitzpatrick skin types V–VI and treatment using both wavelengths together.
Understanding patient suitability
Why Skin of Colour Requires Particular Consideration
Laser treatment outcomes are influenced by more than the wavelength being used.
Skin phototype, pigmentation history, treatment intensity and the individual's response to inflammation can all affect how the skin responds during and after treatment.
One of the particular concerns in darker skin tones is post-inflammatory hyperpigmentation (PIH).
PIH occurs when inflammation triggers an increase in melanin production, creating areas of darker pigmentation following an injury or treatment.
This does not mean fractional laser treatment is automatically unsuitable for darker skin. It means practitioners need to understand the risk and plan treatments accordingly.
The 2026 review is valuable because it examines clinical evidence specifically involving patients whose skin types have historically been less represented in some laser studies.
Two complementary wavelengths
1550nm Erbium Glass & 1927nm Thulium
Both wavelengths are used in non-ablative fractional laser treatments, but their tissue interaction and clinical applications are not identical.
1550nm Erbium Glass
The 1550nm wavelength is particularly relevant to deeper dermal remodelling and has been investigated for acne scarring, selected pigmentation concerns and skin rejuvenation.
The treatment creates microscopic thermal zones that stimulate a healing and remodelling response without the extensive surface removal associated with ablative resurfacing.
1927nm Thulium
The 1927nm wavelength has a more superficial treatment profile and is particularly relevant to pigmentation, photoageing and improvements in overall skin quality.
Its different interaction with water within the skin allows practitioners to address concerns that may require a different treatment depth from 1550nm Erbium Glass.
Evidence from published studies
What Did the Clinical Research Find?
Although the studies differed in treatment protocols, participant numbers and outcome measurements, several consistent findings emerged.
Acne Scarring
Studies examining 1550nm Erbium Glass generally reported improvements in acne scarring among patients with skin of colour.
However, the degree of improvement varied between studies, and treatment intensity could also influence adverse effects.
Melasma & Pigmentation
Studies using 1550nm and 1927nm wavelengths reported improvements in selected pigmentation concerns, including melasma.
Melasma remains a complex and potentially recurrent condition. Laser treatment requires careful selection and should not be viewed as a universally suitable first-line option.
Photoageing
Research involving 1927nm Thulium reported improvements in visible photoageing and pigmentation-related skin concerns.
These findings support the wavelength's potential role in professionally selected skin-rejuvenation programmes.
Dermal Remodelling
Histological findings showed changes associated with dermal repair and remodelling, including collagen and elastic-fibre changes.
The findings provide a biological explanation for some of the clinical improvements, although several tissue-analysis studies involved small patient samples.
Treatment safety
What Did the Research Reveal About PIH?
One of the most useful aspects of the review is its examination of how treatment settings may influence pigmentation-related complications.
Post-inflammatory hyperpigmentation was reported across a number of the clinical studies reviewed.
Importantly, studies comparing different treatment parameters found that lower energy and/or reduced treatment density could be associated with fewer adverse effects.
This reinforces a practical principle: a more intensive treatment is not necessarily the most appropriate treatment for every patient.
The relationship between intensity, clinical improvement and pigmentation risk must be considered carefully, particularly where a patient has a history of PIH or melasma.
Lower Intensity Does Not Mean No Risk
Conservative treatment parameters may help reduce complications, but they cannot eliminate them.
Patient assessment, appropriate cooling, sun protection and aftercare remain important parts of treatment planning.
Reading the evidence carefully
Where Is More Research Needed?
One of the strengths of this review is that its authors identify the limitations of the available evidence rather than presenting the results as definitive for every patient group.
Across the 15 studies, there were 360 participants. Most were classified as Fitzpatrick skin types III–IV.
Only 29 participants were classified as skin type V, and nine as skin type VI.
The review also found that relatively few studies evaluated the 1927nm wavelength in darker skin types, and none of the included studies directly examined combined treatment with both wavelengths in this population.
These details matter because a clinical finding involving predominantly Fitzpatrick III–IV patients should not automatically be treated as equivalent evidence for Fitzpatrick VI.
What We Can Reasonably Conclude
The evidence is encouraging for selected applications of 1550nm Erbium Glass and 1927nm Thulium in skin of colour, particularly Fitzpatrick III–IV.
However, the available research does not establish that every treatment or treatment setting carries the same benefit or risk across all skin types.
A Note About the Equipment Studied
The published review examines clinical studies involving Fraxel systems and related laser platforms.
The Pure Tone Thulium Laser Pro Dual™ was not the device tested in these studies.
We reference the research to explain the scientific evidence for these wavelengths, not to claim that identical outcomes have been independently demonstrated with our particular machine.
Putting research in context
What Does This Mean for Clinics?
For practitioners, the value of clinical research lies in how it informs patient assessment and treatment planning.
- Assess Fitzpatrick skin type alongside any history of PIH, melasma or other pigmentation concerns.
- Differentiate superficial pigmentation and tone concerns from deeper textural or scarring objectives.
- Choose treatment settings according to the patient and the specific laser system being used.
- Consider conservative energy and coverage settings where pigmentation risk warrants additional caution.
- Include cooling, sun protection and appropriate aftercare within the treatment pathway.
- Explain realistic improvement, possible adverse effects and the potential need for repeat treatments.
- Follow machine-specific training, appropriate clinical protocols and relevant regulatory requirements.
A useful additional source is the 2022 paper by Friedman and colleagues, published in Dermatologic Surgery.
It provides expert guidance on 1550nm Erbium Glass and 1927nm Thulium treatment applications, including recommendations across different Fitzpatrick skin types.
These recommendations relate to the laser systems and clinical experience described in the publication. They should not be transferred directly to a different machine as preset treatment protocols.
Pure Tone professional laser technology
Where Thulium Laser Pro Dual™ Fits
Pure Tone's Thulium Laser Pro Dual™ combines 1927nm Thulium and 1550nm Erbium Glass within one professional fractional laser platform.
The two wavelengths offer different treatment depths, giving practitioners additional flexibility when considering pigmentation, tone, texture and selected scarring concerns.
Understanding the published research helps explain the clinical principles behind these wavelengths.
However, choosing the right equipment also involves practical considerations: training, treatment planning, installation, ongoing support and the needs of the clinic's existing patients.
Pure Tone provides CPD-approved, nurse-led practical training, alongside machine delivery, installation and ongoing clinical and technical support.
We would be happy to discuss the capabilities of Thulium Laser Pro Dual™, the training provided and how the system might fit your clinic.
Transparency and attribution
Published Research & Further Reading
The scientific papers discussed in this article were written by independent research authors.
1. Goldman et al. — February 2026
Goldman MP, Wu DC, Khetarpal S, Jacobson A, Wang JV, Geronemus RG.
Dual 1550-nm Erbium Glass Fiber and 1927-nm Thulium Fiber Non-ablative Fractional Laser System Treatment in Patients With Skin of Color: A Review of Clinical Studies and Unmet Needs.
Lasers in Surgery and Medicine. Published 10 February 2026.
Read the original published review →
2. Friedman et al. — 2022
Friedman PM and colleagues.
1,550 nm Erbium-Doped and 1,927 nm Thulium Nonablative Fractional Laser System: Best Practices and Treatment Setting Recommendations.
Dermatologic Surgery. 2022;48(2).
Read the original published paper →
Editorial Note
These papers were not written, conducted or commissioned by Pure Tone Aesthetics.
This Journal article provides our own educational discussion of the published findings.
The studies referenced should not be interpreted as clinical trials of Pure Tone's Thulium Laser Pro Dual™.
Clinical research questions
Frequently Asked Questions
Can 1550nm Erbium Glass laser be used on darker skin?
Published studies report improvements in scarring and selected pigmentation concerns in patients with skin of colour. However, PIH remains a risk, and suitability depends on individual assessment and carefully selected treatment parameters.
What does the research say about 1927nm Thulium in skin of colour?
Some studies report improvements in photoageing and pigmentation. However, the 2026 review found fewer studies involving 1927nm than 1550nm, with particularly limited evidence in Fitzpatrick skin types V–VI.
Does non-ablative fractional laser treatment eliminate the risk of hyperpigmentation?
No. Post-inflammatory hyperpigmentation was reported in the published research. Risk depends on skin type, patient history, treatment parameters and aftercare.
Were these clinical studies conducted using Pure Tone Thulium Laser Pro Dual™?
No. The studies examined other laser platforms, including Fraxel systems.
They provide evidence about the clinical use of these wavelengths, rather than device-specific results for Pure Tone's machine.
The clinical perspective
Encouraging Evidence. Careful Treatment Planning.
The published research supports an important principle: 1550nm Erbium Glass and 1927nm Thulium can offer useful treatment options for selected skin concerns in patients with skin of colour.
But effective treatment is not determined by wavelength alone.
Patient assessment, appropriate settings, aftercare and an honest understanding of the limits of the evidence remain central to responsible clinical practice.
Technology · Training · Support
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Learn more about Thulium Laser Pro Dual™ and the practical training and ongoing support we provide to clinics introducing fractional laser treatments.