Filler substances such as collagen can be used to fill in fine lines, scars, and deep wrinkles. Results are immediate. Lips are often injected to create a more sculpted or fuller appearance. Traditional collagen lasts about three months and requires allergy skin testing. Newer fillers such as Restylane, Artecoll, and Radiance can last longer (four months to years), and most of these do not require skin testing.