Inflammatory Suppression by Endodontic Sealers After Aging 12 Weeks In Vitro

Dental endodontic sealers are in intimate contact with tissues around the root apex (periapical area) for extended periods. New endodontic sealers have been developed in the past decade, but the biological responses to many new products are not well documented. In this study, we assessed in vitro monocytic cytotoxic and inflammatory responses to several contemporary endodontic sealers. AH-Plus (AH), Pulp Canal Sealer (PC), Epiphany (EPH), Endo-Rez (ER), and an experimental Endo-Rez (ERx) were initially placed in buffered-saline for 12 weeks to simulate in vivo use. After "aging," specimens were placed in direct contact with THP1 monocytes for 72 It and their cytotoxicity (mitochondrial response; MTT) or ability to trigger or suppress cytokine secretion (ELISA; TNF alpha, IL1 beta, IL=6; +/- lipopolysaccharide (LPS) exposure) were measured relative to Teflon (R) (Tf) negative controls. Cellular responses among conditions were compared with ANOVA and Tukey post-hoe analysis (alpha = 0.05). Two of the five sealers, EPH and PC, still suppressed cell mitochondrial activity by 70% or more after 12 weeks of conditioning in saline. No sealer alone activated monocytic TNF alpha, IL1 beta, or IL6 secretion (p > 0.05 vs. +LPS controls). When THPI were activated by LPS after exposure to the sealers, differential suppression of TNF alpha, IL1 beta, and IL6 secretion was observed for two of the five sealers tested. (EPH and PC) This data suggest that common endodontic sealers do not activate monocytic TNF alpha, IL1 beta, and IL6 secretion in vitro by themselves, but degradation products of the sealers may suppress activation of monocytes. (C) 2009 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 91B: 839-844, 2009