Hyaluronic acid is a naturally occurring substance in our skin, Its function is to provide fullness and elasticity to the skin. As we age, our skin loses hyaluronic acid, and as it diminishes our skin loses volume - increasing the chance for wrinkles and folds to appear. Restylane and Perlane both contain hyaluronic acid and is tolerated well by the skin. In fact, Restylane is the worlds best selling dermal filler. Perlane consists of larger molecules intended to be injected deeper into the skin.