Hybrid laser: thinner hairs

For someone considering laser hair reduction, a better result could mean fewer hairs, finer regrowth or less time spent shaving. Those are different outcomes. A measurement of shaft diameter cannot, by itself, tell us how much easier a person's routine becomes. That distinction is the useful question behind a study published on 1 October 2026 in Lasers in Medical Science.

The comparison favoured a combined 755/1064-nm laser mode over 755-nm alexandrite alone for making hairs thinner. But it was a small, non-randomized study, and the researchers did not establish that the extra change was perceptible to patients. Nor did they demonstrate a between-mode advantage in the number of hairs per square centimetre.

## What “28% greater” actually describes

Among the 36 participants who completed the protocol, mean hair thickness fell by 30.6% with the hybrid mode and 23.9% with the single wavelength, from baseline to week 20. The authors describe that as approximately 28% greater relative thickness reduction. It is not 28% more hair removed.

The absolute difference in thickness reduction was 0.00461 mm, with a 95% confidence interval of 0.00209–0.00713 mm (p=0.0007). That is a measurable statistical advantage. Its everyday meaning remains uncertain: no established threshold says how large a trichoscopic thickness difference must be before patients find it worthwhile. The study also lacked a formal quantitative assessment of photographs by blinded graders.

Hair density decreased with both treatments. The additional reduction with the hybrid mode was not statistically significant (p=0.238). This does not prove that the modes are equivalent, and it does not mean neither worked. It means this comparison did not demonstrate an added density benefit.

## A useful comparison, with boundaries

Each participant received both modes on matching areas, which helps reduce differences between people. Treatment sides alternated according to enrollment order; allocation was not random or concealed. There were three sessions four weeks apart. Of 41 enrolled adults, four were lost to follow-up and one withdrew after an adverse event; the main efficacy analysis included only 36 completers, without an intention-to-treat sensitivity analysis.

Twenty-nine completers were men, all had skin types III or IV, and legs accounted for 22 of the 36 treatment sites. These results cannot settle the choice for every skin type, sex or body area. The settings also differed in energy delivery, so the study cannot isolate the effect of adding a second wavelength. Week 20 cannot answer how much hair returns later.

## Comfort is another outcome

Satisfaction showed no significant difference. Pain was slightly higher with the hybrid mode at the second session only, a finding requiring caution because secondary comparisons were not adjusted for multiple testing. There were no device-related events at hybrid sites and two crusting events at single-mode sites; one required escharectomy and led to withdrawal. With only 41 people in the safety analysis, those counts do not establish superior safety.

Wontech supplied equipment and an unrestricted grant. The authors report no sponsor role in the research or publication decision and no other competing interests. For readers, the study sharpens the question to ask of a claimed improvement: improvement in which outcome, over what period, and large enough to matter? Longer, randomized comparisons with patient-centred outcomes are needed to connect thinner measured hairs to a meaningful daily benefit.