Microneedling creates thousands of microscopic channels in the skin and can be categorized as either medical or cosmetic. There are many different types of microneedling devices including rollers, stamps and electronic devices.
Cosmetic microneedling devices contain needles that are 0.1 to 0.3mm in length and create microscopic channels to increase the absorption of topical products into the skin. Cosmetic microneedling also stimulates keratinocytes (skin cells) to release growth factors, which increases cell turnover.
Medical microneedling devices contain needles that are 0.5 to 3mm in length, which produces a controlled skin injury without damaging the epidermis. These microinjuries set up a wound-healing cascade. This stimulates keratinocytes and fibroblasts to release various growth factors resulting in accelerated epidermal cell turnover and increased collagen, elastin and glycosaminoglycan (e.g. hyaluronic acid) production. The needles also physically breakdown scar tissue and allow it to revascularize. Studies have shown improvements in scar appearance, wrinkles and skin surface irregularities with microneedling treatments. Medical microneedling devices are to be used by physicians, nurses and other trained skincare professionals, not at home.