Filler is a cosmetic treatment used to smooth wrinkles or pitted scars on the skin, usually on the face. They are also used to make the lips fuller When injected under the skin, a filler raises or puffs up that area It is important to make sure of the brand and quality of the material used in the procedure and it is as important to choose the experienced doctor who has an artistic vision to make sure you get the look that you want.