Microneedling is a procedure in which an instrument with multiple rows of tiny needles is rolled over the skin to elicit a wound healing response and stimulate collagen production to reduce the appearance of atrophic acne scars in people with darker skin color.[140] Notable adverse effects of microneedling include postinflammatory hyperpigmentation and tram track scarring (described as discrete slightly raised scars in a linear distribution similar to a tram track). The latter is thought to be primarily attributable to improper technique by the practitioner, including the use of excessive pressure or inappropriately large needles.[140][147]

Previous purchases and returns: If you have signed up for an account we will store information regarding (i) your online purchases and returns, and (ii) your purchases and returns in physical stores, if you have provided your e-mail address to our personnel. Such information encompasses product, size, price and date of purchase. We will also store information regarding your recently viewed items. This will allow you to keep track of your purchases and returns, and recently viewed items, by logging into your personal account. The legal basis is our legitimate interest to provide you with the service of a personal account as requested by you when you signed up for the account. You may choose to deregister your account at any time. We will also save information on your contact details and previous purchases and returns during 36 months after the purchase to be able to administer returns and/or complaints. The legal basis is our legitimate interest to provide our customers with speedy and efficient service after the purchase.
Several scales exist to grade the severity of acne vulgaris, but no single technique has been universally accepted as the diagnostic standard.[68][69] Cook's acne grading scale uses photographs to grade severity from 0 to 8 (0 being the least severe and 8 being the most severe). This scale was the first to use a standardized photographic protocol to assess acne severity; since its creation in 1979, the scale has undergone several revisions.[69] The Leeds acne grading technique counts acne lesions on the face, back, and chest and categorizes them as inflammatory or non-inflammatory. Leeds scores range from 0 (least severe) to 10 (most severe) though modified scales have a maximum score of 12.[69][70] The Pillsbury acne grading scale simply classifies the severity of the acne from grade 1 (least severe) to grade 4 (most severe).[68][71]
Pimples are raised red spots with a white center that develop when blocked hair follicles become inflamed or infected with bacteria. Blockages and inflammation that develop deep inside hair follicles produce cystlike lumps beneath the surface of your skin. Other pores in your skin, which are the openings of the sweat glands, aren't usually involved in acne.