Ultrasonic scalpel is a cosmetic means developed by scientists in the United States in recent years. Its main principle is through ultrasound waves, which are aggregated at multiple points at a certain depth, making the temperature at that point as high as 60℃ or 65℃. Since the ultrasound does not polymerize at the point where it contacts the skin, it does not harm the surface skin. Multi-point linear coagulation at different depths can cause multi-point coagulation in the SMAS layer of the face. After repeated ultrasonic scalpel treatments, the entire SMAS layer of subcutaneous tissue can be caused to tighten, and the fascial layer of subcutaneous tissue can be tightened to achieve the effect of lifting the skin. However, ultrasonic knife surgery is actually not as perfect as everyone imagines, and its side effects include: 1. If the skin is seriously lacking in collagen and hyaluronic acid, it will cause mild scarring, resulting in permanent skin damage, unbalanced skin nutrition, uneven skin surface, or even permanent skin collapse, uneven skin tone and other side effects; 2. The high temperature of the procedure will destroy the skin’s surface moisturizing layer, resulting in dry skin; 3, High-temperature focused electroshock process will evaporate a large amount of moisture under the skin, resulting in abnormal dry skin; 4, you can’t use masks frequently after ultrasonic scalpel, otherwise it will affect the recovery of subcutaneous trauma; 5, it is easy to produce postoperative hyperpigmentation.