Influence of chlorine dioxide on cell death and cell cycle of human gingival fibroblasts.
OBJECTIVE
The effects of chlorine dioxide (ClO2), sodium hypochlorite (NaOCl), and hydrogen peroxide (H2O2) on cell death and the cell cycle of human gingival fibroblast (HGF) cells were examined.


METHODS
The inhibition of HGF cell growth was evaluated using a Cell Counting Kit-8. The cell cycle was assessed with propidium iodide-stained cells (distribution of cells in G0/G1, S, and G2/M phases) using flow cytometry. The patterns of cell death (necrosis and apoptosis) were analyzed using flow cytometry with annexin V-FITC/PI staining.


RESULTS
The lethal doses for 50% of the cells (LD50) of ClO2, NaOCl, and H2O2 were 0.16, 0.79, and 0.11 mM, respectively. All three dental disinfectants induced G0/G1 cell cycle arrest. H2O2 induced apoptosis at concentrations of 0.05 and 0.1 mM, while NaOCl and ClO2 did not induce significant apoptosis at any concentration examined.


CONCLUSIONS
These results suggest that ClO2 is sufficient for use as a dental disinfectant compared with H2O2 or NaOCl.
Nishikiori
Ryo
R
Department of Biomaterials Science, Graduate School of Biomedical Science, Hiroshima University, Hiroshima 734-8553, Japan.
Nomura
Yuji
Y
Sawajiri
Masahiko
M
Masuki
Kohei
K
Hirata
Isao
I
Okazaki
Masayuki
M
D017209:Apoptosis / Q000187:drug effects; D002452:Cell Count; D002453:Cell Cycle / Q000187:drug effects; D016923:Cell Death / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D017606:Chlorine Compounds / Q000633:toxicity*; D005347:Fibroblasts / Q000187:drug effects*; D016193:G1 Phase / Q000187:drug effects; D016195:G2 Phase / Q000187:drug effects; D005881:Gingiva / Q000166:cytology / Q000187:drug effects*; D006801:Humans; D006861:Hydrogen Peroxide / Q000633:toxicity; D007928:Lethal Dose 50; D008422:Materials Testing; D009336:Necrosis; D016877:Oxidants / Q000633:toxicity; D010087:Oxides / Q000633:toxicity*; D016192:Resting Phase, Cell Cycle / Q000187:drug effects; D012388:Root Canal Irrigants / Q000633:toxicity*; D016196:S Phase / Q000187:drug effects; D012973:Sodium Hypochlorite / Q000633:toxicity
D017606:Chlorine Compounds; D016877:Oxidants; D010087:Oxides; D012388:Root Canal Irrigants; C025109:chlorine dioxide; D006861:Hydrogen Peroxide; D012973:Sodium Hypochlorite