[The injectable collagens. Technique of implantation, indications, limits]

Collagen implants have extended our therapeutic possibilities: used either alone or as a complement to surgical methods, they are an answer to the demand of many patients (who are carefully selected on clinical and immunological criteria) for obvious short-term efficacy, the frequency of complementary injections to complete filling, depending on the location of the areas treated. The main reservation lies in the onset of phenomena of local delayed hypersensitivity, which appears to be reduced as far as possible by concomitant performance of the skin and serum tests for anti-collagen antibody. Human, placental collagen, which has not yet been marketed nor have the purified fluid silicones which are currently experiencing a revival of interest, may be the future hope for these often ignored allergies.