Matériaux de comblement : techniques et effets indésirables

Injectable fillers made of degradable or nondegradable compounds are being increasingly used to treat wrinkles and hollows or to improve the contour of the face. Bovine collagen and hyaluronic acid are the main degradable products; polylactic acid is used less often. Side effects may occur: Immediate and minor side effects consist of dot-like hematomas, erythema, or mild edema, which resolve within 48 to 72 hours.Semi-delayed side effects include a variable degree of inflammatory edema that is tender to the touch and persists for 2 to 7 days then resolves completely. Pigmentation that fades slowly over 3 to 6 months may occur with hyaluronic acid, most notably in the nasolabial fol. Delayed side effects consist of erythema and, above all, erythematous or purplish granulomas with a variable degree of induration. In exceptional cases, the lesion may be cyst-like and/or purulent with abscess formation. These lesions usually develop 1 to 4 weeks after the injection but may arise even later or after several injection sessions. The immediate and semi-delayed side effects are minimal and short-lived. When treated promptly, delayed granulomas resolve within a few weeks without leaving any visible marks. Hypersensitivity responses to collagen can be prevented by performing two intradermal tests 15 days apart before the collagen injection. In selected cases (history of autoimmune disorders, allergic disease, or reactions to bovine collagen), intradermal testing should be performed also before injecting hyaluronic acid. As compared to nondegradable fillers, which cause major side effects, biodegradable products seem satisfactory in terms of cosmetic results and medical safety.