Skin closure mainly refers to closed acne, which is formed due to the blockage of pores by keratinized cells, and is mainly manifested as pimples with white keratin inside, which can develop into inflammatory pimples and pustules with the progression of the disease. 1. Closed acne, also known as whitehead acne, is formed when skin follicles are blocked by keratinized cells. The main manifestation is the appearance of multiple small pimples on the skin of the face, often densely distributed but not fused with each other, and the surface of the pimples is covered with epidermis and contains white keratin plugs. Usually there is no pain, itching and other discomfort. 2. Generally, smaller closed pimples will subside within 3~4 days on their own, while larger ones may take weeks or months. If there are cases of prolonged emotional upset, improper diet, improper facial cleansing, etc., closed pimples may progress gradually, resulting in the formation of inflammatory papules, pustules, nodules, etc., which lead to skin damage. It is recommended that after the appearance of closed acne on the facial skin, pay attention to a reasonable diet, regular rest and relaxation, and consult a doctor in a timely manner, under the guidance of the doctor for treatment.