A laboratory investigation indicated that the cell-damaging potential seemed to match the degree of leaching of particular polymer-based endodontic materials. The methacrylate-based polymeric root canal sealing materials were responsible for this effect: Even the cured materials leached components and caused cells of oral origin to die when kept in contact with material extracts. The severity of cell death increased with the time that the material was available in the cell culture.

Leaching from endodontic materials

One of the studied materials was epoxy-based and two contained a mixture of various methacrylate compounds. All uncured material extracts caused increased cell death, although much less so when an epoxy- rather than a methacrylate-based material was in contact with the cells.

Leachables of endodontic materials were analysed, for the first time, by the combined use of gas chromatography/mass spectroscopy and liquid chromatography/mass spectroscopy methods. The compound bisphenol-A diglycidyl ether leached from the epoxy-based material and was well tolerated by the cells in this study. Among the leachables from the methacrylate-based materials were triethylene glycol dimethacrylate (TEGDMA), urethane dimethacrylate (UDMA), hydroxyethyl methacrylate (HEMA) and polyethylene glycol dimethacrylate (PEG-DMA).

These laboratory results may help in identifying the relative cell-damaging potential of polymer-based composite dental materials and can, when confirmed by similar findings and clinical observations, give an indication of the safety of such materials.

The full study is described in the follwing
Lodienè G, Kopperud HM, Ørstavik D, Bruzell EM.
Detection of leachables and cytotoxicity after exposure to methacrylate- and epoxy-based root canal sealers in vitro.
Eur J Oral Sci 2013;121(5):488–496.

NIOM Newsletter September 2013