Usually the scab will fall off naturally in about 7 days, but the exact time of falling off will depend on the size of the wound. Wound scab is a normal physiological reaction of the body, mainly a clot of platelets and fibrin on the wound surface. If there is no inflammation when the wound is crusted, the crust can protect the wound from infection and facilitate wound healing; if there is inflammation when the wound is crusted, the crust may lead to wound ulceration and aggravate wound suppuration, and the inflammatory wound must be cleaned promptly when the crust appears to avoid ulceration. It should be noted that the wound must be kept clean and hygienic after crusting, disinfection treatment with alcohol regularly, avoid stimulating or rubbing the wound crust, the rubbing may cause the scab to fall off earlier and there is a possibility of infection. In addition, patients should eat more protein and vitamin-rich food after the wound scabbing, and avoid spicy, fishy and other irritating foods to promote wound healing.