Previous studies have shown that residual monomers, initiators, and additives are eluted from methacrylate-based dental composite materials. Recently, a composite material (Filtek Silorane), based on a new resin chemistry, was introduced. The purpose of this study was to investigate substances eluted from Filtek Silorane in water and ethanol. Polymerized specimen discs of the material were immersed in either distilled water or 75 vol% ethanol at 37 degrees C, and the solutions were analyzed using liquid chromatography-mass spectrometry after 1, 4, 24, and 72 h eluting time. No substances were found to leach from Filtek Silorane in water, whereas silorane monomers and an initiator component were eluted from the material into the ethanol solution.