Abrasion, also known as dermabrasion, is a restorative procedure in which the epidermis and the papillary layer of the dermis are ground to improve irregularities on the surface of the skin with the aim of making it smooth, flat and close in color to normal skin. The earliest dermabrasion was performed with a cylindrical knife file, which later developed into abrasion of scarred skin with sterilized sandpaper rolled on an empty cylinder of varying thickness, and later improved to hand-held sand or stainless steel abrasive heads, and now commonly used are dental drills or special grinding machines with sand or stainless steel abrasive heads of varying shape, size and thickness, grinding at 5000-10000 rpm, and newer ones with laser abrasion technology and microcrystalline grinding technology. The microdermabrasion technique has a shallower grinding depth than laser or grinder grinding, but is safer, requires repeated treatments and takes longer time. Microdermabrasion is suitable for superficial scars left after acne, smallpox, chickenpox, herpes zoster, eczema, trauma, burns or surgery, and usually more satisfactory results can be achieved after 2-3 times of grinding. For example, for the treatment of depressed scar left after acne, before grinding, use a sharp knife blade to cut the scar to the dermis layer to loosen it, or remove part of the scar with obvious depressions and a large area, and pull it together and suture it directly, and then perform grinding, while the grinding wound heals, the excised part also heals at the same time, and the effect is better than that of simple grinding. For small-scale grinding, the procedure can be performed on an outpatient basis and the patient can leave the hospital for recuperation after the procedure. For patients with a larger grinding area or older age, inpatient surgery is required. It is not easy to perform grinding for people with scarring, localized infected lesions and more serious physical diseases. Complications after abrasion include hyperpigmentation and loss, scar growth, infection, and erythema. The most common complication is hyperpigmentation, which is mainly caused by the damage and irritation to the skin during the grinding procedure and ultraviolet radiation after the procedure, and usually starts to appear one month after the procedure, reaches a peak in two months, and fades after six months to one year. If the scar is too deep, it is likely to cause local scar growth. Therefore, the surgeon must have rich clinical experience and strictly control the grinding depth, and should be more cautious in the periocular and perioral areas where the skin is thin. Be sure to choose a regular hospital and an experienced surgeon and consult with the surgeon carefully before choosing the grinding procedure. After the surgery, you should know in advance some problems that may occur after the grinding procedure and prevent them. For 3 months after grinding, strictly avoid direct sunlight and wind and sand stimulation, and take vitamin C, vitamin E and antibacterial agents orally. The scabs on the grinding surface should fall off naturally, do not forcibly tear off the dried scabs on the surface, and apply 3%-5% hydroquinone cream externally after the scabs are removed to prevent pigmentation.