Acne scars are one of the most studied indications for microneedling. The mechanical injury stimulates collagen production in the dermis, gradually filling in atrophic scars. But the protocol matters more than the device.

Treatment Frequency

Acne scars require 3 to 6 sessions spaced 4 to 6 weeks apart. The interval between sessions matches the skin’s wound healing cycle. When the skin is needled again before the previous collagen remodeling is complete, the results do not accumulate and the risk of scarring increases.

Depth Requirements

Shallow boxcar scars respond to 1.0 to 1.5 millimeter depth. Rolling scars require 1.5 to 2.0 millimeters. Ice pick scars may benefit from 2.0 to 2.5 millimeter depth combined with TCA cross or subcision performed by a dermatologist.

Post-Treatment Products for Scar Revision

Growth factor serums applied immediately after treatment improve scar filling outcomes. A 2022 study published in the Journal of Cosmetic Dermatology found that patients who applied growth factor serum after each microneedling session had 35 percent greater scar depth reduction at 6 months compared to the control group.

Sunscreen is critical for scar revision patients. UV exposure on healing scars increases the risk of post-inflammatory hyperpigmentation, which can make scars appear worse than they were before treatment. Mineral SPF 50 applied every two hours outdoors is the minimum protection required.