Microneedling instruments shown here (from Reddit)

My comment: The needle length should be 1 -= 1.5 mm long to reach the growth center of the hair follicle. Read this article: https://ift.tt/2BSxKcR The question raised is how often does the dermaroller (microneedling) need to be done and for how long? The article doesn’t really answer this question but does show the superiority of using microneedling with minoxidil...

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