Evaluation of the toxicity of denture base polymers after subcutaneous implantation in guinea pigs

Abstract

n L/ata on the biologic actions of monomeric and polymeric methyl methacrylates indicate that localized toxicity is caused primarily by the methyl methacrylate (MMA) released from denture base polymers (DBP) and bone cements.’ The polymerized material itself seems to be well tolerated by tissues.’ Adverse effects caused by the chemotoxic activity of dental polymers have been investigated by cell culture techniques in vitro, animal studies in vivo, and by clinical observations on patients treated with removable dentures and fixed partial dentures.*-” The data are not conclusive and do not provide for an adequate selection of a denture base polymer for clinical use. Differences in experimental design and lack of standardization may account for inconsistent results. No generally accepted standard method for evaluation of the toxic effects of denture base materials under clinically realistic conditions is available.‘? In clinical trials traumatic factors have masked the possible adverse effects of leachable components from dentures.Y, ‘” For the evaluation of toxicity, the applied test must ascertain that the chemotoxic effects of the polymerized materials are tested. Standardized subcutaneous implantation has proved to be an efficient and reproducible method for revealing differences in the biologic performance of dental materials.“, ” In the present investigation, denture base polymers selected on the basis of their conditions of polymerization were implanted subcutaneously in guinea pigs. The purpose was to evaluate differences in tissue response to the polymers. MATERIAL AND METHODS