The principle and role of ultrasonic knife are as follows: the principle is to repair the skin through polymer energy waves, so that the heat in the dermal fiber layer emits an effective physical effect of thermal damage, thus enabling the skin to start repairing cells again and promoting the role of cell growth again. And for collagen also has the effect of stimulating growth, on achieving a lifting face, to achieve the purpose of improving skin rejuvenation. The main role of ultrasonic knife is to solve the facial wrinkles, such as head lines, fine lines around the eyes, decree lines, neck lines, and prevent the aging of the neck skin. It has an important role in reshaping the facial contour, lifting the skin to make the face more three-dimensional and removing excess fat. But after ultrasonic knife surgery must do a good job of sun protection, you can hold an umbrella, wear a hat, wear sunscreen, apply sunscreen, and can not eat spicy, greasy food, a short period of time need to avoid smoking, alcohol.