To achieve the robust volume that you are looking for, it may be best to use a hyaluronic acid filler with a thicker, more viscous consistency. A couple of examples that have already been mentioned here by other doctors include Juvederm Ultra Plus and Restylane. While the different HA products are all made with hyaluronic acid, they display different properties due to the nature of cross-linking between these molecules which is created through bio-engineering during the manufacturing process. A thicker filler is due to a greater extent of cross linking. Hyaluronic acid is able to hold a large number of water molecules for a seamless, hydrated and natural looking appearance. In your quest for the perfect lips, it is not only important to choose the right filler, but also an experienced provider who would be able to determine the amount of product to use as well as the correct injection points.