Comparison of 2940 nm Er: YAG laser treatment in the microlaser peel, fractional ablative laser, or combined modes for the treatment of concave acne scars

To compare and analyze the effects of Er:YAG laser treatment in the microlaser peeling, fractional ablative laser, or combined modes for the treatment of concave acne scars. Ninety patients of concavity acne scar were randomly assigned to three different groups:microlaserpeeling mode group (MM group), fractional ablative mode group (FM group) and combined mode group (CM group). MM group received microlaserpeeling mode with depth of 60 μm and a repetition rate of 20%, FM group received fractional ablative mode with depth of 300 μm and a fractional density of 8%, and CM group received a fractional depth of 200 μm, density of 8%, and a peeling depth of 30 μm, repetition rate of 20%. All patients were evaluated for their treatment effects and side effects 30 days after treatment, including the treatment satisfaction, the ECCA grading scale, pain score and pigmentation level. According to the effect satisfaction of patients' self-assessment, the difference among the three groups was statistically significant (P .05). About the ECCA grading scale 30 days after treatment, the statistical result among the three groups was significant (P