Recovery and Pigment Safety in the 2026 Split-Face Acne Scar Trial: Sample Size and Evidence Limits for People With Atrophic Acne Scars

The 2026 split-face acne scar trial compares 755-nm picosecond laser against 1565-nm nonablative fractional laser for atrophic acne scars. Atrophic acne scars are depressed scars where past acne destroyed collagen, and a split-face trial treats one side of the face with one method and the other side with another. Recovery is shorter and pigment risk is lower with less-ablative sides than with ablative fractional CO2 laser. Evidence remains limited because recent split-face scar trials are small and short, so results guide decisions rather than promise permanent clearance.

Medical information disclaimer: This article is for general educational purposes only and does not provide medical advice, diagnosis, or treatment. Always consult a physician or other qualified health professional about symptoms, medications, tests, or treatment decisions.

What did the 2026 trial test?
How long does recovery take?
Who needs extra pigment caution?
Why do sample size and follow-up matter?
Frequently Asked Questions

What did the 2026 trial test?

Qi, Li and Shu ran a 20-week prospective randomized split-face study of atrophic acne scars, according to the 20-week comparison in Lasers in Medical Science. One cheek received 755-nm picosecond laser. The other cheek received 1565-nm nonablative fractional laser.

That design controls for skin type, age, sun exposure, and healing. Each person serves as their own comparison. Differences in texture, redness, and dark marks reflect treatment, not person-to-person variation.

How long does recovery take?

Fractional CO2 laser recovery commonly involves 5-10 days of redness, crusting, and peeling, versus 3-7 days for less-ablative options. One comparative study reported downtime over 3 days in 40% of laser-treated sides versus 16% for microneedling, according to the JCC Practice prospective comparison.

Plan for visible peeling, tightness, and pinkness during that window. Ask your clinic about:.

Daily sun avoidance, gentle cleansing, and plain moisturizer
When to return if crusting spreads, pain rises, or blisters form
Makeup, exercise, and shaving pauses during peeling

Who needs extra pigment caution?

Ablative sides carry higher post-inflammatory hyperpigmentation risk, reported as 20% versus 4% against microneedling, and 24% on fractional CO2 sides versus none on fractional picosecond 1064-nm sides, according to the OUCI record of the randomized split-face trial. Hyperpigmentation means dark patches that appear after inflammation or injury.

People with Fitzpatrick skin types III-VI, including Asian patients, face higher prolonged redness and hyperpigmentation risk. That makes pigment-safe nonablative lasers clinically important for medium to deep skin tones.

Why do sample size and follow-up matter?

Recent split-face atrophic-scar trials are small, typically 14 to 34 participants. One example enrolled 14 patients with bilateral scars and assessed them at 5 and 10 weeks.

Small groups cannot capture rare burns, infections, or stubborn pigment changes. Short 10- to 20-week follow-up cannot show whether pits stay smoother after one year. Patients should plan strict sun avoidance and clinician-monitored recovery rather than expecting permanent single-session results, according to the Dermatology Times journal digest.

Frequently Asked Questions

Does the 2026 trial prove one laser erases acne scars?

No. It compares two sides over 20 weeks in a small single-center design, so it shows relative improvement and tolerability, not lifetime clearance.

I have medium or brown skin. What should I ask?

Ask about prolonged redness and dark-mark risk, prior results in Fitzpatrick types III-VI, test spots, sun protection, and follow-up for pigment changes.

Is a vitamin C, vitamin E, and ferulic acid serum part of laser recovery?

A separate January 2026 investigator-blinded split-face trial tested that serum after ablative fractional CO2 laser; ask your dermatologist whether any aftercare product suits your treatment and skin type.