Aim: The purpose of this study was to evaluate and compare the cytotoxicity and genotoxicity of two bioceramic root canal sealers: EndoSequence BC and iRoot SP with zinc oxide eugenol sealers on fibroblast cell line.

Materials and methods: The sealers tested were zinc oxide eugenol, EndoSequence BC, and iRoot SP. Each material was mixed according to the manufacturer’s instructions and mounted into sterile polyethylene color-coded rings, for cytotoxicity and genotoxicity evaluation.
After 48 hours, the set materials were transferred to previously marked wells and cytotoxicity evaluation to L929 murine fibroblast cells was done by 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. The percentages of viable cells were then calculated and values were statistically analyzed by Kruskal-Wallis test.
The evaluation of genotoxicity of the materials to L929 murine fibroblast cells was carried out by Comet assay. To quantify deoxyribonucleic acid (DNA) damage, the following comet parameters were evaluated in the assay using Comet scoring software: tail length, tail moment, and Olive moment. The values were statistically analyzed using Kruskal-Wallis test with a significance value set to p < 0.05.

Results: The results of the study showed that both cytotoxicity and genotoxicity evaluation by MTT assay and Comet assay can be done on L929 murine fibroblast cell line. Among the three tested materials, zinc oxide eugenol showed maximum cytotoxicity to the cells (30.64% viable cells), followed by EndoSequence BC (71.33% viable cells) and iRoot SP (75.11% viable cells). The evaluation of DNA damage by genotoxicity assessment showed iRoot SP to be least genotoxic followed closely by EndoSequence BC. Zinc oxide eugenol was genotoxic and induced more DNA damage on the fibroblast cell line studied. The statistical analyses for both the assays were nonsignificant.

Conclusion: All the three tested sealers showed varying degrees of cytotoxicity and genotoxicity while using fibroblast cell line. Zinc oxide eugenol was most toxic in both the assays and iRoot SP showed least toxicity, followed closely by EndoSequence BC.

Keywords: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, Comet assay, Cytotoxicity, Endosequence BC, Fibroblasts, Genotoxicity, iRoot SP, L929, Zinc oxide eugenol.

How to cite this article: Nair AV, Nayak M, Prasada LK, Shetty V, Kumar CNV, Nair RR. Comparative Evaluation of Cytotoxicity and Genotoxicity of Two Bioceramic Sealers on Fibroblast Cell Line: An in vitro Study. J Contemp Dent Pract 2018;19(6):656-661.

Source of support: Nil

Conflict of interest: None