ABSTRACT
The first clinical research using injectable animal collagen was conducted on burns patients in the 1970s (Stanford). In 1975, the Collagen Corporation, based in Palo
Alto, released Zyderm® I especially designed for cosmetic and esthetic use. Zyderm I (like the later released products Zyderm II and Zyplast®) is a genuine cosmetic medication with controlled manufacture, conservation, and purification processes. Food and Drug Administration (FDA) approval was obtained in 1981. In 1983, Zyderm II was released and in 1985, Zyplast was released. In France, since 1987, these three products have
been legally available (French legal approval for drugs and medical devices). To date, the follow-up with injectable collagen is over 25 years, and several million patients have been treated. More than 280 clinical series have been published in the literature.1-4
This medication is made of natural collagen, harvested, extracted, and highly purified, from bovine dermis (Cheptel Collagen USA). Antigenically inactivated, this material is used as a substitute for altered or lost native collagen. Biologically assimilable, it is made of 95% type I col-
lagen and 5% type III collagen. This material fits the skin dynamics perfectly, and induces fibroblastic activation with stimulation of neocollagen synthesis. Based on histological studies,5 Zyderm persistence after injection is 3-4 months. Over this time, protein synthesis of fibrocytes is stimulated, with dermal tissue spread. Histological Zyplast tissue persistence is longer
(18 months). Nowadays, three complementary presentations are
available:
• Zyderm I: 35mg/ml • Zyderm II: 65mg/ml • Zyplast: reticulated collagen, characterized by
interlysine bridges between collagen molecules that enhance fibrillar network cohesion and the stability of the product. This product is available in a 3% lidocaine premixed presentation.
