Clinical Efficacy and Histologic Correlation of a High-Powered 675-nm Non-Ablative Diode Laser for Facial...

The 675-nm diode laser has emerged as a novel wavelength for non-ablative skin rejuvenation, with potential advantages in selective dermal targeting and minimal epidermal injury. However, integrated clinical and biologic evidence across multiple esthetic domains remains limited. This study aimed to evaluate the efficacy and safety of high-powered 675-nm laser treatment for facial rejuvenation in a real-world clinical setting.

In this prospective single-center study, 22 adults with facial erythema, fine wrinkles, enlarged pores, and textural irregularities underwent 3 monthly sessions of 675-nm non-ablative diode laser treatment. Objective outcomes were assessed using three-dimensional imaging at baseline and the 3-month follow-up (T3). Blinded Global Esthetic Improvement Scale (GAIS) evaluations were performed for pigmentation and erythema. An exploratory histologic analysis was conducted in a subset of participants.

Eighteen participants completed the paired imaging analysis. Significant improvements were observed in wrinkle (+0.73 ± 0.86, p = 0.002), pore (+1.54 ± 2.24, p = 0.010), and smoothness scores (+2.18 ± 2.35, p = 0.001), with large effect sizes (Cohen's d_z 0.69-0.93). Blinded GAIS assessments demonstrated ≥ 50% improvement in 61.1% of participants for both pigmentation and erythema. Treatment-related pain was mild (median visual analog scale score: 2.0), and no serious adverse events or post-inflammatory hyperpigmentation were observed. Histologic findings suggested increased dermal collagen components.

High-powered 675-nm non-ablative diode laser treatment significantly improved objective skin texture parameters and provided clinically perceptible improvements in pigmentation and erythema, with favorable tolerability. These findings support its role as a versatile and effective modality for comprehensive facial rejuvenation.