The role of fillers in aesthetic medicine: medico-legal aspects.

: In recent years there has been an exponential increase of fillers use in aesthetic medicine. The popularity of this anti-wrinkle product is based on their capacity to offer significant improvement in the aesthetic field, particularly to skin rejuvenating processes with non-invasive and less expensive techniques, if compared to the surgical methods (i.e. surgical lifting). The great number of fillers on the market is composed of a large heterogenic number of biomaterials. The aim of this review was to provide an overview and a classification of the filling materials that are most commonly used. A synthesis of the literature concerning fillers and related side effects was also reported. The law decree no. 23 of 1998, converted in the law no. 94 of 1998 and the principal judgments of the Italian Court of Cassation have been examined with the medico-legal issues related to fillers use in medicine. With respect to their degradation, filler materials may be classified as temporary (degradable), semi-permanent and permanent (not degradable). The temporary fillers such as hyaluronic acid and collagen are completely degraded by the surrounding tissue in a few months. The permanent fillers, such as the ones derived from silicon oil and minerals are not biodegradable and may cause serious and irreversible side effects. Their use requires a physician with a high level of specialization to perform the treatment, a deep knowledge of face anatomy and a great degree of experience.