There are two reasons why acne has left a depression. One is acne infection, with abscesses and pustules. In order to discharge pus, or the pustule breaks and hurts the dermis, it will definitely leave scars; Another possibility is that you belong to the scar constitution, and even a small wound may leave obvious scars. The problem of acne scar covers the epidermis, dermis and subcutaneous tissue of the skin, and the consequences include skin damage, tissue defect and scar formation, which not only causes skin appearance defects, but also affects the normal tissue structure of the skin. In order to improve the problem of acne marks and acne marks, it is necessary for doctors to diagnose and evaluate different types of scars to determine the treatment plan. Personally, I suggest using the French navy as a salary, which is a holy product for acne.