Closed pimples are not always clinically closed. Closed pimples are actually only one of the types of pimples, such as closed pimples, and clinical pimples include closed pimples and open pimples. Due to the partial opening of the sebaceous ducts, the closed acne produces a certain amount of discharge, and a certain amount of blackheads are created on the surface due to the oxidation of air, dust, impurities, etc. This is also called blackhead acne. Blackhead acne belongs to the open acne, and is two kinds of cases.