Comparative evaluation of 5% sodium hypochlorite and Nd:YAG laser in reducing endotoxins level from infected root canals – An in vivo microbiological study

Abstract
Objectives: Endodontic infection is one of the most challenging aspects of dental treatment which is primarily caused by Gram-negative anaerobic bacterial species. The primary objective in the management of endodontic treatment is eradication of bacteria, as well as elimination of endotoxin. The aim of this study was to compare the effectiveness of 5% sodium hypochlorite, a mixture of calcium hydroxide+2% chlorhexidine (CHX) gel and Nd:YAG lasers for decreasing the level of endotoxin in infected root canals. Material and Methods: Forty four patients in the age group of 18–50 years were carefully chosen for the study and divided into control (Group 1, n = 11) and experimental group (Group 2, n = 33). Experimental group was further split into three subgroups according to the medicaments used. Samples were collected after the access opening (pre-operative specimens), after the biomechanical preparation (intermediate samples), and after the application of intracanal medicament for 15 days. The concentration of endotoxin in each sample was measured using quantitative chromogenic limulus amebocyte lysate assay. The data collected were statistically analyzed using SPSS for Windows (Statistical Package for the Social Sciences, Inc., Chicago, IL,) Version 15.0 Statistical Analysis Software. The level of significance was set at 0.05 for all tests. Results: Pretreatment endotoxins level observed was 6.783EU/ml in Control group and 7.261EU/ml, 6.963EU/ml, 7.247EU/ml in experimental subgroups. After biomechanical preparation and use of medicaments endotoxins level reduced to 3.919EU/ml in Control group and 0.5222EU/ml (sodium hypochlorite) 1.164EU/ml (calcium hydroxide+chlorhexidine), 0.841EU/ml (laser). Conclusion: This study concluded after analyzing the data that use of 5% sodium hypochlorite and Nd:YAG laser was effective in decreasing the level of endotoxins and use of intracanal medicament (2% CHX+ calcium hydroxide) for 15 days further helps to reduce the endotoxin level.