Applications of microneedling for various dermatologic indications with a special focus on pigmentary disorders: A comprehensive review study.

Microneedling can accelerate skin repair through numerous complex processes triggered by micro-injuries it produces on the skin surface with very thin needles. The current growth in the application of microneedling in the treatment of cutaneous diseases can be explained by its numerous effects on the skin as reported in the literature. Despite the numerous studies conducted on the application of microneedling in the treatment of skin lesions, its effects on pigmented skin lesions have remained relatively unexplored. The present review comprises an examination of the evidence for the application of microneedling in skin diseases in general and a comprehensive review of the applications of microneedling in pigmentation disorders. The review involved a search of all clinical studies, including trials, case reports, and case series, in the databases MEDLINE/PubMed and Google Scholar using the following keywords: "microneedling," "dermal needling," "percutaneous collagen induction," "skin needling," "dermaroller," and "dermatology disorder." Pertinent data were extracted from all relevant articles published from 1990 to April 2021, and focused on the application of microneedling in the treatment of pigmented skin lesions. Despite the limited number of available studies, evidence suggests the effectiveness and safety of microneedling in treating vitiligo, melasma, and periorbital hypermelanosis. It is noteworthy that the combination of any type of non-aggressive needing technique with other effective therapies (especially topical agents and mesotherapy) yields more promising therapeutic results than single therapy for melasma, dark cycles, and vitiligo as the prototype of pigmentary disorders. However, single needling therapy is significantly effective, too.