Facial fillers, such as Juvederm® or Restylane®, are popular, non-surgical in-office cosmetic treatments for facial rejuvenation. They are made of hyaluronic acid, a naturally hydrating substance. They are used to fill in deep creases, scars or facial contours (e.g. smile lines). They restore volume under the skin in order to smooth away facial wrinkles and folds and give a more youthful, natural appearance.