Alexidine versus chlorhexidine for endodontic irrigation with sodium hypochlorite

Abstract

Objective:The objective of this study was to chemically evaluate precipitate formation on irrigation by different concentrations of chlorhexidine (CHX) and alexidine (ALX) with sodium hypochlorite (NaOCl).Materials and Methods:Six test tubes were prepared with 1 ml of 4% NaOCl. One milliliter of 2%, 1%, 0.5%, and 0.25% ALX was added to the first four, and in the last two, 1 ml of 2% CHX and 0.2% CHX was added, respectively. Samples were observed for color changes or precipitates at multiple time intervals. All solutions were then centrifuged at 1000 rpm for 10 min and re-examined for precipitates. This process was repeated twice. Fifty freshly extracted premolars were biomechanically prepared, dried, divided into two groups, and irrigated with 10 ml of 4% NaOCl and 10 ml of 2% ALX (Group 1) and 10 ml of 4% NaOCl and 10 ml of 2% CHX (Group 2). These samples were sectioned and observed for precipitates on the dentinal surfaces by scanning electron microscopy (SEM).Results:The color of the solution of ALX and NaOCl stayed transparent and no precipitate was observed. A color change was noted immediately on mixing CHX and NaOCl which did not change with time. Precipitates were only observed in the solutions of CHX with NaOCl and after centrifuging them. SEM views also showed dense precipitates covering the dentinal surface and occluding the dentinal tubules in Group 2.Conclusion:The interaction of ALX and NaOCl does not produce precipitates which together with its better antimicrobial action make ALX a more effective and safer replacement for CHX as an adjunctive endodontic irrigant.

Insight into the Reaction of Alexidine with Sodium Hypochlorite: A Potential Error in Endodontic Treatment

“…Interaction between ALX and NaOCl has been described and discussed previously [19,24,25]. Kim et al [19] and Jain et al [24] suggested that ALX can be a potential alternative for CHX solution in endodontic treatment.…”

“…Interaction between ALX and NaOCl has been described and discussed previously [ 19 , 24 , 25 ]. Kim et al [ 19 ] and Jain et al [ 24 ] suggested that ALX can be a potential alternative for CHX solution in endodontic treatment. ALX was reported to have a similar chemical structure and properties and be even more potent in deactivating bacteria virulence factors than CHX.…”

“…If so, ALX would be particularly useful as the final irrigant in the irrigation protocol, making it the last chemical compound that has contact with root canal dentin. However, the authors of those studies did not identify any product formed in the mixture of ALX and NaOCl [ 19 , 24 , 25 ]. Moreover, those studies on ALX–NaOCl interaction denied precipitate formation [ 19 , 24 ].…”

“…However, the authors of those studies did not identify any product formed in the mixture of ALX and NaOCl [ 19 , 24 , 25 ]. Moreover, those studies on ALX–NaOCl interaction denied precipitate formation [ 19 , 24 ]. In the present work, it has been affirmed that different aliphatic amines are produced from the reaction of ALX and NaOCl.…”

“…Kim et al [ 19 ] and Jain et al [ 24 ] mixed ALX with NaOCl and observed color changes in the reaction solutions in test tubes, which was followed by observation of precipitates on the dentinal surfaces of teeth samples irrigated with an ALX–NaOCl mixture in scanning electron microscopy (SEM) under ×500 and ×1000 magnification. They did not observe precipitate formation on the dentinal surface [ 19 , 24 ]. In the present study, we have confirmed with more advanced analytical techniques that the yellowish precipitate is formed in the reaction of ALX–NaOCl.…”