The elution and breakdown behavior of constituents from various light-cured composites.

Objectives: Constituents of dental composites can be released from dental fillings after polymerization. The aim of this study was to examine the time-related elution and breakdown of separable constituents of polymerized composites using deuterated solvents.

Method: Elution and breakdown of constituents were investigated with deuterated solvents methanol and water by gas chromatography/mass spectrometry of following composites for 180 days: Filtek™ Supreme XT, Filtek™ Supreme XT Flow, Tetric Ceram(®), Tetric Flow(®), Grandio(®), Grandio(®) Flow.

Results: Within 180 days no compounds were formed as the products of breakdown. 19 compounds were identified as elution products: Bis-EMA, TEGDMA, DDDMA, EGDMA, MAA, BPA, CQ, HQME, DMABEE, CSA, BL, TEG, BHT, TINP, TPP, TPSB, DEDHTP, DCHP, ß-PHEA. The highest concentration of Bis-EMA was measured for Tetric Flow(®) in deuterated methanol on day 90 at 36.993mmol/l and in deuterated water also on day 90 at 0.031mmol/l. The highest TEGDMA concentrations were measured for Grandio(®) Flow in deuterated methanol on day 60 at 1.322mmol/l and for Filtek™ Supreme XT Flow in deuterated water on day 3 at 0.689mmol/l. The highest BPA concentration was measured for Tetric Flow(®) in deuterated methanol on day 90 at 1.469mmol/l. The highest BPA concentration was measured for Grandio(®) in deuterated water on day 180 at 0.007mmol/l. Significance Examination of time-related elution indicates that various elution products (e.g. Bis-EMA, BPA) were only released in small quantities during the first 90 days, but in high quantities between day 90 and day 180.