HISTORY OF DERMAL FILLERS
Soft tissue augmentation is an important tool in present-day cosmetic treatment. First attempts at soft tissue augmentation were made early in the last century with more or less inappropriate material, such as wax, but became more effective and frequent due to the invention of silicone oil by Eugene G. Rochow in 1940. In the 1950s and 1960s, silicone oil was used for various indications, including breast augmentation, body shaping, and wrinkle treatment of the face. This synthetic material showed some intriguing features, such as ease of application and longevity of results, but in the long term, it turned out to be hazardous because of migration, fat tissue damage, granuloma formation, and ulcerations. In the 1970s, purified bovine collagen was available for wrinkle treatment of the face; this marked a change in paradigm from the use of technical products to biological preparations. Collagen was effective and easy to administer, but its duration in the skin was limited to several months, and there was a risk of allergic reaction. Therefore pretesting was mandatory prior to treatment. Nevertheless, collagen remained the most commonly used filler for the treatment of wrinkles of the face for more than twenty years. Finally, early in the 1990s, collagen was replaced as a dermal filler by derivatives of hyaluronic acid (HA). Since then, there has been parallel development of new so-called permanent and semipermanent filler materials, but the use of permanent filler materials still raises the same problems and issues known from past use (and, in some cases, present use) of silicone.