Cytotoxicity of materials used in perforation repair tested using the V79 fibroblast cell line and the granulocyte-macrophage progenitor cells.
OBJECTIVE
To compare the cytotoxicity of materials used to repair perforations using permanent V79 fibroblasts and murine granulocyte-macrophage progenitor cells (CFU-GM).


METHODS
Set specimens from amalgam, glass-ionomer, SuperEBA, N-Rickert, MTA and gutta-percha were eluted with culture medium for 72 h and their cytotoxicities were assessed by incubating the extracts with V79 and bone marrow-derived progenitors for 24 h and 7 days, respectively. Cytotoxicity on V79 cells was judged using the total nucleic acid content (NAC), neutral red uptake (NRU) and reduction of the tetrazolium salt (MTT). The number of bone marrow CFU-GM colonies determined in clonal cultures stimulated with recombinant murine granulocyte-macrophage colony-stimulating factor was used to assess cytotoxicity to progenitor cells. Statistical analyses were conducted using the one-way analysis of variance and Tukey's test where appropriate.


RESULTS
All materials were cytotoxic in both cell systems; however, CFU-GM was more sensitive to the extracts than V79 cells. A similar rank order of toxicity was observed in V79 cells using the NAC and the MTT assays: glass-ionomer > N-Rickert congruent with SuperEBA > gutta-percha > amalgam congruent with MTA (P < 0.05). In contrast, the NRU test exhibited a lower sensitivity to MTA, gutta-percha and amalgam extracts. In the clonal culture assay, the toxicity was less pronounced in the presence of gutta-percha, SuperEBA and MTA. Similar cellular responses were found by placing the set specimens directly in the clonal culture dishes.


CONCLUSIONS
The sensitivity of toxicity depended on the choice of the endpoint and the cell-culture system. Nevertheless, MTA was ranked as the least cytotoxic cement in both cell systems.
Souza
N J A
NJ
Centro Interdisciplinar de Investigação Bioquímica, Universidade de Mogi das Cruzes (UMC), Mogi das Cruzes, Brazil.
Justo
G Z
GZ
Oliveira
C R
CR
Haun
M
M
Bincoletto
C
C
D000180:Acrylic Resins / Q000633:toxicity; D017607:Aluminum Compounds / Q000633:toxicity*; D000818:Animals; D017610:Calcium Compounds / Q000633:toxicity*; D002460:Cell Line; D006224:Cricetinae; D003723:Dental Amalgam / Q000633:toxicity; D017220:Dentin-Bonding Agents / Q000633:toxicity; D004338:Drug Combinations; D005347:Fibroblasts / Q000187:drug effects*; D042381:Granulocyte Precursor Cells / Q000187:drug effects; D006171:Gutta-Percha / Q000633:toxicity; D006412:Hematopoietic Stem Cells / Q000187:drug effects*; D008264:Macrophages / Q000187:drug effects; D051379:Mice; D010087:Oxides / Q000633:toxicity*; D012387:Root Canal Filling Materials / Q000633:toxicity*; D017640:Silicates / Q000633:toxicity*; D012822:Silicon Dioxide / Q000633:toxicity
D000180:Acrylic Resins; D017607:Aluminum Compounds; D017610:Calcium Compounds; D017220:Dentin-Bonding Agents; D004338:Drug Combinations; C080618:N-Rickert sealer; D010087:Oxides; D012387:Root Canal Filling Materials; D017640:Silicates; C015897:glass ionomer; C086631:mineral trioxide aggregate; D012822:Silicon Dioxide; D003723:Dental Amalgam; C084074:Super EBA; D006171:Gutta-Percha