Background: The goal of root canal therapy depends on chemomechanical debridement and three-dimensional filling of the root canal system.[ 1 ] Aim: The aim of this study is to assess the effect of NaOCl + Ethylenediaminetetraacetic acid (EDTA) and Twin Kleen as a final irrigating solution on the depth of penetration of AH Plus and Perma Evolution sealers into the dentinal tubules. Materials and Methods: Forty mandibular premolars were decoronated and instrumented up to size 30. Moreover, randomly assigned into two groups based on final rinse Group A ( n = 20): 5.25% NaOCl + 17% EDTA. Group B ( n = 20): Twin Kleen solution. Resin sealers were labeled with few grains of fluorescent rhodamine B dye and subdivided into two subgroups, Subgroup A1and B1 ( n 1 = 10): AH Plus; Subgroup A2 and B2 ( n 2 = 10): Perma Evolution and obturated. Confocal laser scanning microscopy was used to examine the sections taken 2, 5, and 8 mm from the apex. Images were exported to Image J software to determine the sealer penetration depth. Statistical Analysis: Independent t -test and one-way analysis of variance followed by Tukey's HSD post hoc test. Results: Maximum depth of sealer penetration was seen in Twin Kleen in all sections. Perma Evolution showed highest sealer penetration at the middle and apical third region of root canal for both groups. Conclusions: Final irrigation with Twin Kleen produced highest sealer penetration than with EDTA.

Chemome chanical debridement is accompanied by three-dimensional obturation of the root canal system in endodontic therapy. Endodontic irrigation requires sodium hypochlorite (NaOCl) as it dissolves organic matter and disinfects the root canal. The smear layer is removed by chelating agents. Since neither NaOCl nor the chelator ethylene diamine tetraacetic acid (EDTA) fulfills the entire core function required for an ideal irrigating solution, both are concurrently used. As a result, continuous chelation was introduced. When a chelator is coupled with NaOCl, it has antibacterial and proteolytic properties and even the capacity to eliminate the smear layer. It is not only easier than traditional irrigation, but it also improves antimicrobial effectiveness, removal of dentinal debris, and bonding of root filling materials to dentin.