Ex vivo microbial leakage after using different final irrigation regimens with chlorhexidine Navarro Escobar, Esther Baca García, María Pilar González Rodríguez, María Paloma Arias-Moliz, Teresa Ruiz-Linares, Matilde Ferrer Luque, Carmen María Bacterial leakage Cetrimide Chiorthexidine Enterococcus faecalis Irrigation Objective To assess the influence of final irrigation protocols with chlorhexidine in the coronal leakage of Enterococcus faecalis in filled root canals. Material and Methods Seventy single-root canals from extracted teeth were prepared using ProTaper instruments. The irrigation protocol accomplished an alternating irrigation with 5 mL of 2.5% sodium hypochlorite (NaOCI) and 17% EDTA between each file. The teeth were randomly divided into four experimental groups (n=15) according to the final irrigation regimen: group 1, without final irrigation; group 2, irrigation with 10 mL 2.0% chlorhexidine (CHX); group 3, with a final application of EC40™; and group 4, irrigation with the combination (1:1) of 0.2% CHX + 0.1% cetrimide (CTR). All the teeth were mounted in a two-chamber apparatus and the coronal access was exposed to E. faecalis. The presence of turbidity in the BHI broth over a period of 180 days was observed. The Friedman test was used for statistical analysis. Results EC40™ varnish showed the least leakage at 180 days, and was statistically similar to 2% CHX. No significant differences were observed between the group without final irrigation and the 2% CHX group or 0.2% CHX + 0.1% CTR. Conclusions In this ex vivo study, EC40™ showed the longest delayed coronal leakage of E. faecalis, although without significant differences from 2% CHX. 2014-01-17T11:38:18Z 2014-01-17T11:38:18Z 2013 journal article Navarro Escobar, E.; et al. Ex vivo microbial leakage after using different final irrigation regimens with chlorhexidine. Journal of Applied Oral Science, 21(1): 74-79 (2013). [http://hdl.handle.net/10481/29883] 1678-7755 doi: 10.1590/1678-7757201302322 http://hdl.handle.net/10481/29883 eng open access Universidade de Sao Paulo. Faculdade de Odontologia de Bauru