Abstract
BACKGROUND: Therapeutic quality of endodontic sealers plays a critical role in promoting the success of root canal therapy by blocking entrance of microbes as well as facilitating tissue reparative process. The bioceramic sealers NeoSEALER Flo and CeraSeal have been on the rise owing to their biocompatibility and bioactivity. However, their relations with periapical tissues especially human gingival fibroblasts (HGFs) are still significant determinants of treatment outcomes. This in vitro case intends to analyze the inflammatory reaction of HGFs towards NeoSEALER Flo and CeraSeal bioceramic sealers and AH plus resin sealer as control. MATERIALS AND METHODS: HGFs were cultured and treated with eluates of tested sealers at different dilutions; 25%, 50%, 75% and 100%. The extracts were left in incubator for 1, 3, and 7 days. Cell death was determined by the MTT assay, and the secretion levels of pro-inflammatory cytokines such as IL-6, IL-8, and TNF-α, were measured using q RT-PCR. Furthermore, mRNA and protein levels of some inflammatory markers were also estimated by q RT-PCR. RESULTS: Analysis of the data showed that NeoSEALER Flo was cytotoxic in a concentration-dependent manner to HGFs, though it appeared marginally more toxic than CeraSeal when tested at the same ratios and same time. The high levels of all the measured pro-inflammatory cytokines in HGFs treated with both sealers at a higher concentration with NeoSEALER Flo showing a more intense effect. Having said so, gene expression profiles endorsed these results by showing that both sealers increase the level of IL-6, IL-8, and TNF-α at the higher concentrations. CONCLUSIONS: The study indicates that both NeoSEALER Flo and CeraSeal bioceramic sealers activate HGFs inflammatory response with a slight preference for CeraSeal biocompatibility. Therefore, it becomes important and relevant to assess the cytotoxic and inflammatory propensity of various endodontic materials in order to guide enrolment of these endodontic products in clinical practice and improve the quality of endodontic treatment. Subsequent in vivo works should be done to confirm these in vitro findings as well as to examine the chronic effects of sealer-tissue interaction.