Are synthetic prostheses really inert? Preliminary results of a study on the biocompatibility of Dacron vascular prostheses and Silicone skin expanders.

This study investigates the histo-pathologic reactions induced by implant of prostheses in Dacron knitted double velour and skin expanders in Silicone elastomers. Particular attention was paid to the effect of these reactions on the tissue itself. In the case of vascular prostheses it was found that fibrous connective tissue tended to accumulate in and around the prosthesis. We also observed widespread lymphohistiocytic infiltration and occasional plasmacytes. Numerous foreign body granulomas were found to be grouped around the filaments of plastic material. The prosthesis itself seemed to be composed of filaments of different calibre, fragmented into particles of varying size. Thus the structure of the prosthesis was modified and discontinued along its whole length. A similar granulomatous inflammatory reaction developed in the case of the skin expander, probably due to the leakage of particles of plastic material through the expander wall, which however did not seem to be affected by the tissue reaction. The findings indicate the need for more detailed research into the material used for prostheses, aimed at determining what modifications the tissues can produce in the synthetic material. Also, it is necessary to follow a multidisciplinary approach which takes into consideration the data available from the chemistry of polymers, fluid mechanics and cell biology.