ABSTRACT
AIM AND OBJECTIVE: The aim of the study was to evaluate the changes in free available chlorine (FAC) when 6% sodium hypochlorite (NaOCl) is admixed with irrigants 17% ethylenediaminetetraacetic acid (EDTA), 2% chlorhexidine (CHX), and 0.2% chitosan in varying proportions of 90:10, 80:20, and 50:50. MATERIALS AND METHODS: The 25 mL aliquots of 6% NaOCl were admixed in varying proportions of 90:10, 80:20, and 50:50 with secondary irrigation solutions: (a) 17% EDTA, (b) 2% CHX, (c) 0.2% chitosan. Iodometric titration was done to evaluate the change in FAC. STATISTICAL ANALYSIS USED: Kruskal-Wallis and Mann-Whitney tests. RESULTS: On titration, the mean FAC value of NaOCl at baseline was 1.99 g%. On mixing NaOCl with EDTA, the FAC decreased in all the three proportions and the values were 0.17 g%, 0.17 g%, and 0.06 g% at 90:10, 80:20, and 50:50 ratios, respectively. pH obtained was 9.55 at 50:50 ratio. On mixing NaOCl with CHX, FAC reduced and the values were 1.84 g%, 1.72 g%, and 0.27 g% at 90:10, 80:20, and 50:50 ratios, respectively. pH obtained was 10.87 at 50:50 ratio. On mixing NaOCl and chitosan, the FAC remained unaltered in all the three proportions and the values were 1.64 g%, 1.51 g%, and 1.63 g% at 90:10, 80:20, and 50:50 ratios, respectively. pH obtained was 11 at 50:50 ratio. CONCLUSION: Combination of NaOCl and chitosan did not lead to a reduction in FAC and the pH of the solution remained unaltered, suggesting that tissue-dissolving property of NaOCl might be preserved. CLINICAL SIGNIFICANCE: The combination of chitosan with NaOCl is advantageous in two ways. Firstly, FAC remained unaltered and the pH of the solution was also maintained at 11.05 indicating that the tissue-dissolving property of NaOCl prevailed. Secondly, chitosan is known for its chelating property and is effective in smear layer removal. With further in vivo and in vitro studies, a combination of chitosan and NaOCl can be proposed as a novel irrigant.
