There are many types of injection. Paraffine, Vaseline, and liquid silicone that were popular in the past and collagen, which is popular recently. Besides, there are Perlane, Rofilan, Reviderm, Juvederm, and Restylane, which are types of Hyaluronic acid. Also, Aquamid, Amazing gel, Interfall, which are types of Polyacrylamide; and Artecoll, Bioplastique, which are types of Polymethylmetaacrylate. There are still so many of which we can't even remember their names. However, injection is not a solid material so there is a bit of difference later on, but apparently it will spread out and become flat. Injections are not recommendable.