If the patient has a slight redness or hardness of the local skin just after the injection of hyaluronic acid, it may be the following cases: 1. It is normal and need not be too worried because after the injection of hyaluronic acid, the skin and local soft tissues will have a short edema period; 2. When the patient performs three-dimensional chin shaping, he usually chooses large-molecule hyaluronic acid, which has a harder texture and stronger viscosity, and the shaping effect is also better and more stable The chin can be maintained for a longer period of time, and the retention time in the body is relatively long, thus making the local skin hard; 3. Hyaluronic acid filling of the chin is in the subcutaneous fat layer, close to the periosteum, if the injection level is too shallow and the amount is too much, it will make the hand feel worse and the skin shiny and hard; 4. The aesthetician chooses irregular institutions, doctors and filling products, and improper postoperative care, which leads to infection and There is a hard lump in the chin along with redness and swelling symptoms. Therefore, if after the edema period, patients still continue to have red skin or local hard lumps, they should seek medical consultation in time.