Organic leachables from resinbased dental restorative : characterization by use of combined gas chromatographymass spectrometry

During the last decade resin-based dental restorative materials have replaced amalgam as the first choice dental filling material. Resin-based dental restorative materials are complex polymers containing a variety of monomers and filler particles, as well as initiators, activators, stabilizers, plasticizers and other additives. Several studies have shown that many of the ingredients are leaching from the materials, even after adequate polymerization. It is known from in vitro studies that some of the compounds in the resin-based materials have cytotoxic, genotoxic or estrogenic potential. Allergenic effects in patients and dental personnel have also been reported. The aim of this study was to identify and quantify substances released from various types of resin-based dental restorative materials. Specimens were polymerized according to protocols from the producers and submerged in different solvents. To characterize a maximum elution potential, ethanol was used as an immersion media. Furthermore, immersion in Ringer’s solution and saliva was used to mimic clinical elution conditions. A combined Gas Chromatography - Mass Spectrometry (GC-MS) technique was used for the identification and quantification of eluates. The majority of eluting substances from the polymeric matrix are organic substances with low molecular weight, which are well suited for analysis by GC-MS. Tailor-made internal standards for HEMA and TEGDMA were synthesized for the quantification procedure. We have identified and quantified a number of compounds from several materials. Significant differences regarding type and amount of leachables between the materials are observed