Cytotoxicity of dental composite components and mercury compounds in pulmonary cells

Abstract

The cytotoxic potentials of the dental composite components triethyleneglycoldimethacrylate (TEGDMA) and 2-hydroxy-ethyl-methacrylate (HEMA) as well as mercuric chloride (HgCl 2) and methyl mercury chloride (MeHgCl) were investigated. Proliferating A549 and L2 cell monolayers were cultured in the absence or presence of composite components or mercurials. Twenty-four hours later the tetrazolium salt XTT (sodium 3′-[1-phenyl-aminocarbonyl)-3,4-tetrazolium]bis(4-methoxy-6-nitro)benzenesulphonic acid) was added. Formazan formation was quantified using a microtiter plate reader. EC 50 values were obtained as half-maximum-effect concentrations from fitted curves. EC 50 values were in A549 cells (mean values±standard deviation; n=12; μmol/l): HEMA 8854±1882; TEGDMA 1821±529; HgCl 2 41±7 and MeHgCl 27±3. EC 50 values in L2 cells were: HEMA 191±28; TEGDMA 112±16; HgCl 2 25±6 and MeHgCl 8±6. All tested substances induced a dose-dependent loss of viability in A549 and L2 cells after 24 h. The EC 50 values of both mercurials were significantly ( p<0.05) lower compared to the values of both composite components. TEGDMA was about 5-fold (A549 cells) and about 2-fold (L2 cells) more toxic compared to HEMA. It is to be assumed that the risk of lung cell damage by dental composite components is even more unlikely.