They are absorbable substances by the organism that play the role of filling or giving support to the skin in areas where its been lost as in the case of wrinkles and the nasiofold area. Duration of these substances, like the hyaluronic acid, may be of 1 year approximately.
The patient that wishes fillings to be applied to her has to make sure she is using the principles or brands approved by the regulation health system from its country of origin.