Efficacy and safety of non-thermal nitrogen plasma versus long-pulsed Nd:YAG laser for hand rejuvenation.

This randomized controlled study aimed to investigate the efficacy and safety of multiple treatment sessions of pulsed non-thermal atmospheric pressure nitrogen plasma compared with long-pulsed Nd:YAG laser for hand rejuvenation. To optimize the nitrogen plasma mode for rejuvenation, the relative intensity of reactive species and skin temperature was compared at different input powers and time periods. Twenty-five patients with mild-moderate photodamaged skin were recruited; one hand was randomly selected for eight weekly treatment sessions with plasma (two passes), while the other was subjected to three monthly treatments with laser (until erythema became obvious). A blinded dermatologist scored the mean wrinkle and dyschromia improvement at 1 and 2 months after the first treatment and 1 and 3 months after the last treatment. The patients' satisfaction and the biomechanical characteristics of the skin including cutaneous resonance running time (CRRT), melanin, transepidermal water loss (TEWL), and hydration were evaluated. Clinically, both methods gave rise to a similar, significant improvement in wrinkles (49.09 ± 19.18% and 39.32 ± 18.21% after plasma and laser, respectively) and dyschromia (45.00 ± 26.32% and 30.62% ± 24.99% after plasma and laser, respectively) (P < 0.05). A significant decrease in CRRT and melanin was seen following treatment with either method (P < 0.05). Notably, plasma therapy led to a significant decrease in TEWL and boosted skin hydration. This is while laser therapy augmented the TEWL and reduced skin hydration. Our findings corroborate that cold plasma is as effective and safe as long-pulsed Nd:YAG laser, with less discomfort and dryness during treatment. The protocol was approved by the Iranian Registry of Clinical Trials. IRCT20160320027109N4. Registered 9 April 2019 (This manuscript is only a part of this registered project.).