Resin-based dental restorative materials contain allergenic methacrylate monomers, which may be released into saliva after restorative treatment. Monomers from resin-based composite materials have been demonstrated in saliva in vitro; however, studies analyzing saliva after restorative therapy are scarce. The aim of this study was to quantify methacrylate monomers in saliva after treatment with a resin-based composite filling material. Saliva was collected from 10 patients at four start points–before treatment, and 10 min, 24 h, and 7 d after treatment–and analysed by combined chromatography/mass spectrometry. The monomers bisphenol-A diglycidyl methacrylate (Bis-GMA), 2-hydroxyethyl methacrylate (HEMA), and urethane dimethacrylate (UDMA) were detected and quantified in the samples collected shortly (10 min) after treatment. The amounts detected ranged from 0.028 to 9.65 μg ml(-1) for Bis-GMA, from 0.015 to 0.19 μg ml(-1) for HEMA, and from 0.004 to 1.2 μg ml(-1) for UDMA. Triethyleneglycol dimethacrylate (TEGDMA) was detected in four of the samples. Ethoxylated bisphenol-A dimethacrylate (Bis-EMA) was not detected. Monomers were not detected in saliva samples collected before treatment, or 24 h or 7 d after treatment, with the exception of one sample, 24 h after treatment, in which HEMA was detected. In conclusion, monomers from the investigated resin-based composite and adhesive system were present in saliva shortly after treatment. One week after treatment, no monomers could be detected in patients’ saliva samples.

Detection and quantification of monomers in unstimulated whole saliva after treatment with resin-based composite fillings in vivo.
Michelsen VB, Kopperud HBM, Lygre GB, Björkman L, Jensen E, Kleven IS, Svahn J, Lygre H. Eur J Oral Sci. 2012 Feb;120(1):89–95. doi: 10.1111/j.1600-0722.2011.00897.x. PMID: 22288926