title: Studies on cytotoxic effect of nickel ions on three cultured fibroblasts.
abstract: Cytotoxicity of Ni ions on three fibroblasts such as L929, Balb/3T3 clone A31 and MC3T3-E1 were examined by cell count (CC) and Neutral Red assay (NR). Three cells were incubated for 6 days in 1 ml DME medium containing Ni ions which ranged from 0 to 2 mM/l. The results clarified that Ni ions had dose-dependent cytotoxicity. L929 possessed the largest TC50 values (the amount of Ni ion that caused 50% cell death or 50% cell viability) of 0.12 mM/l (CC) and 0.32 mM/l (NR), and Balb/3T3 clone A31 had the least values of 0.05 mM/l (CC) and 0.09 mM/l (NR), whilst MC3T3-E1 had the intermediate values of 0.08 mM/l (CC) and 0.15 mM/l (NR). The dissolution of Ni ions from Ni-containing metallic restorations must be lower than these concentration levels so that body tissues might not be severely damaged.
authors.affiliation: Department of Dental Materials Science and Technology, Osaka University Faculty of Dentistry, Osaka, Japan. mtaira@iwate-med.ac.jp
authors.forename: M
authors.initials: M
authors.lastname: Taira
authors.forename: M S
authors.initials: MS
authors.lastname: Toguchi
authors.forename: Y
authors.initials: Y
authors.lastname: Hamada
authors.forename: J
authors.initials: J
authors.lastname: Takahashi
authors.forename: R
authors.initials: R
authors.lastname: Itou
authors.forename: S
authors.initials: S
authors.lastname: Toyosawa
authors.forename: N
authors.initials: N
authors.lastname: Ijyuin
authors.forename: M
authors.initials: M
authors.lastname: Okazaki