In vitro cytotoxicity analysis of bioceramic root canal sealers on human gingival fibroblast cells and human osteoblast-like cells

Introduction: Cytotoxicity of bioceramic (BC) root canal sealers (RCS) are not well understood due to the limited scientific data. Previous research focused on comparing the conventional and BC RCS but there was no comparison between the latter. This study aims to evaluate the cytotoxicity of BC RCS and to propose the material that is less cytotoxic for clinical purposes. Methods: GuttaFlow Bioseal, MTA Fillapex, CeraSeal BC RCS and iRoot SP RCS were mixed according to the manufacturers’ instructions and placed into a sterilised cylindrical silicone mold of 5mm diameter and 3mm thickness. Fourier transform infrared spectroscopy was used to analyse changes in the quality and consistency of all BC RCS. Human gingival fibroblast (hGFC) and osteoblast-like cells (hOLC) were cultivated and exposed to the material extracts for 24 h, 48 h and 72 h in a 5% CO2 humidified incubator at 37 °C. The MTT (3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide) assay was conducted to determine cell viability. Cell viability was qualitatively graded as severe ( 90%). Results: GuttaFlow Bioseal showed less cytotoxicity followed by CeraSeal BC RCS, iRoot SP RCS, and MTA Fillapex when exposed to hGFC. The percentage of cell viability for all BC RCS was increased from 24 h to 72 h. When the hOLC were exposed to material extracts, GuttaFlow Bioseal and MTA Fillapex showed inconsistent cytotoxic effects, however GuttaFlow Bioseal appeared to be less cytotoxic than MTA Fillapex. CeraSeal BC RCS and iRoot SP RCS were more cytotoxic throughout all incubation periods. Conclusions: It could be suggested that the cytotoxicity of BC RCS was influenced by the types of materials, incubation periods and types of culture cells. Clinicians should select BC RCS that have low cytotoxic effects during root canal treatment procedure