Radiesse is calcium hydroxyappatite and is not the same as dental enamel. When injected into the soft tissues of the face it dissolves over a year or more. It does not feel hard like dental enamel to the touch when injected as a filler.
Radiesse is composed of calcium hydroxylapatite suspended in a gel. The product does completely dissipate. The gel is absorbed over time, while the CaHa crystals act as a scaffold for fibroblasts to deposit new collagen.
Eventually CaHa is broken down into calcium and phosphate ions which are absorbed by the body.