RESUMO
BACKGROUND: Medical-grade injectable silicone for use in soft tissue augmentation is administered subcutaneously by injections of the pure material. OBJECTIVE: To examine histologically and immunohistochemically the characteristics of medical-grade silicone and to identify the advantages and disadvantages of the serial puncture technique. RESULTS: In early biopsies, perivascular lymphocytic infiltration with the characteristic reaction of delayed hypersensitivity (doses, 0.05-0.07 mL) was observed. Immunohistochemically, small local deposits of IgG and IgA were observed around the walls of small vessels. In later biopsies, the inflammation had progressed to a fibroblastic reaction. Additionally, the implantation of large doses provoked giant cell granulomas. CONCLUSIONS: Small doses (0.05-0.07 mL) of injected silicone produce an immunologic and fibroblastic reaction in the skin. The use of this substance with the serial puncture technique is not hazardous when proper technique is used.