Polylactic acid works best mainly on the lower half of the face and achieves the filling of lines caused by laughter as well as the filling of deep nasolabial folds. At the same time, it gives very good aesthetic results in the area of the cheeks, replenishing the lost volume. This material differs from hyaluronic acid, because its action is not immediate. By activating the production of collagen by the patient's body, the results appear gradually after a few months.