Fillers contain hyaluronic acid and are injected into the dermis, which is the second layer of the skin. Hyaluronic acid is a molecule that is found naturally in our skin, joints, muscles and many other components of the body. As we age, we lose volume in many areas of our face. Fillers are used to augment areas where volume is needed, such as the lips, cheekbones, the back of the nose, the chin, dark circles, etc. The filler can last from 6 to 18 months, depending on the body's metabolism. There are several brands available on the market, the doctor uses Restylane for its variety and longevity.