Hyaluronic acid is the most basic substance in human tissue construction, which is actually a kind of mucopolysaccharide and can be divided into large molecules, medium molecules and small molecules. The difference between the three is as follows: 1. Large molecule hyaluronic acid has the role of filling and shaping, mainly used for breast augmentation, buttock augmentation, nose augmentation, chin augmentation and other shaping surgery, the filling site is deep tissue, also can be used to remove wrinkles, hyaluronic acid is injected into the dermal depressions in the form of fillers, such as lips, cheeks, chin, etc., which can be maintained for a long time; 2. Medium molecule hyaluronic acid is often used to remove wrinkles, the injection site is often However, like large-molecule hyaluronic acid, the injection site is also deep tissue and cannot fill the surface layer of the skin; 3.Small-molecule hyaluronic acid is a water-like hyaluronic acid molecule, which is mainly used for injection into the dermis of the whole face. It can make up for the shortage of large and medium molecule hyaluronic acid. In most microplastic injections, the larger molecules of hyaluronic acid are first injected in deeper locations to hold up the body with harder textured objects, and then smaller molecules of hyaluronic acid are used to fill in the dermis near the surface, thus smoothing the skin surface.