Unlike many other fillers, which consist of hyaluronic acid, Radiesse consists of synthetically produced smooth calcium hydroxylapatite microspheres suspended in a sodium carboxymethylcellulose gel carrier. The microspheres almost like microscopic cartilage or bone, and stimulate the body to lay down more of its own collagen. The gel is inert (non-reactive) and is absorbed by the body. It is believed by the Bioform company that this process makes Radiesse last longer than other fillers.
It is important to note that Radiesse is indicated for the correction of deep lines, such as nasolabial folds where it show excellent results. It is not to be used for correction of lips or around the eyes.