Pattern of cell death after in vitro exposure to GDMA, TEGDMA, HEMA and two compomer extracts.
OBJECTIVE
In vitro exposure to chemical compounds in dental materials may cause cell death by apoptosis, necrosis or a combination of both. The aim of this paper was to evaluate aqueous extracts of freshly cured compomers Freedom (SDI) and F2000 (3M ESPE), and constituents identified in the extracts, GDMA (glycerol dimethacrylate), TEGDMA (triethylene glycol dimethacrylate) and HEMA (2-hydroxyethyl methacrylate) for their ability to induce necrosis and apoptosis in primary rat alveolar macrophages and the J744A1 macrophage cell line.


METHODS
The cells were exposed to either extracts of freshly cured samples of the products or to one of the constituents identified in the extracts. Cytotoxicity and necrosis were assayed by MTT test and fluorescence microscopy, respectively. Apoptosis was assayed by fluorescence microscopy and flow cytometry.


RESULTS
Concentration-related apoptosis and necrosis were found in both cell types after exposure to extracts from Freedom and F2000. GDMA appeared to be the most cytotoxic of the tested constituents in the J744A1 cell line as evaluated by the MTT test. TEGDMA was more cytotoxic than HEMA using the MTT test and fluorescence microscopy, whereas HEMA caused a greater accumulation of apoptotic cells seen by fluorescence microscopy and flow cytometry. For various concentrations of HEMA and TEGDMA, the extent of apoptosis appeared inversely related to the cytotoxicity evaluated by the MTT test.


CONCLUSIONS
As an apoptotic response elicits less inflammatory response in the surrounding tissues than a necrotic process, the role of cell death pattern could be important for the evaluation of the biocompatibility of dental materials.
Becher
Rune
R
Noraic Institute of Dental Materials, Haslum, Norway. rune.becher@fhi.no
Kopperud
Hilde Molvig
HM
Al
Ronald H
RH
Samuelsen
Jan Tore
JT
Morisbak
Else
E
Dahlman
Hans Jörgen
HJ
Lilleaas
Edel Marie
EM
Dahl
Jon E
JE
D000818:Animals; D017209:Apoptosis; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D020770:Compomers / Q000633:toxicity*; D005434:Flow Cytometry; D005899:Glass Ionomer Cements / Q000633:toxicity; D008264:Macrophages / Q000187:drug effects*; D008297:Male; D008689:Methacrylates / Q000633:toxicity; D051379:Mice; D009336:Necrosis; D011092:Polyethylene Glycols / Q000633:toxicity; D011109:Polymethacrylic Acids / Q000633:toxicity; D051381:Rats
D020770:Compomers; C118368:F2000 cement; C477332:Freedom Compomer; D005899:Glass Ionomer Cements; D008689:Methacrylates; D011109:Polymethacrylic Acids; C020946:triethylene glycol dimethacrylate; D011092:Polyethylene Glycols; C005044:hydroxyethyl methacrylate