Efficacy of Combined 1927nm Thulium Fiber Laser and Supramolecular Salicylic Acid in Photoaging Treatment

Prior to each session, Compound Lidocaine Cream (Beijing Ziguang Medication Manufacture Corporation Ltd.) was administered topically to the participants' faces for a duration of 30-40 minutes. Following sterilization with alcohol, the entire facial area was treated with a 1927 nm fractional thulium fiber laser (TFL) (WONTECH, Lavieen, South Korea). TFL parameters included a pulse energy of 8-10 mJ, an output power of 10 W, and a pulse spacing of 0.8 mm, ensuring comprehensive coverage of photodamaged regions.

30% SSA (SSA and placebo are provided by Broda ,Shanghai Rui Zhi Medicine Technology, Shanghai, China.) or placebo(the base material of 30% SSA) were randomly assigned to be applied on one side of the face immediately after completion of the 1927nm TFL treatment. The 30% SSA was maintained on facial skin until reaching the clinical endpoint, manifested as mild erythema and/or a characteristic frost-like epidermal whitening. Additionally, the combination therapy side of the subjects was treated with one session of 30% SSA biweekly and 2% SSA daily over a period of 16 weeks.