Complete cleaning of the root canal system requires the elimination of organic and inorganic debris including the smear layer. Endodontic irrigation alone is unable to ensure adequate removal of deeply entrenched bacteria in the dentinal tubules. Use of a chelating agent in conjunction with endodontic irrigants is necessary. The most commonly used chelating agent is EDTA. However, it has certain disadvantages when used with Sodium hypochlorite like reduction in dentin microhardness and lesser antimicrobial activity. The search for alternatives to EDTA has brought up newer alternatives like Etidronic acid and Chitosan solution. Clinical studies have proved that these are equivalent to EDTA in certain actions during endodontic treatment. This study aims to compare the changes in dentin microhardness seen when cleaning and shaping of the root canal system is done using EDTA, Etidronic acid and 0.2% Chitosan solution. Results of this study showed that both Etidronic acid and 0.2% Chitosan had comparable effects on dentin microhardness which were similar to EDTA.