Newer chelating agents

I read with great interest the article by Melissa Good et al regarding endodontic solutions which was published in the May 2012 issue of your journal (Dent Update 2012; 39: 239–246). I wanted to share a few of my thoughts on the newer agents which have been used to remove the smear layer. (a) 7% Maleic acid has been shown to be significantly more effective than 17% EDTA in removing the smear layer from the apical third of the root canal system.1 It has also been found to be less cytotoxic when compared to 17% EDTA.2 Also, unlike EDTA, maleic acid does not form any precipitate when combined with 2% chlorhexidine gluconate.3 (b) 0.2% Chitosan has been shown to be effective in smear layer removal, especially in the middle and apical thirds of the root canal system.4 (c) 37% Phosphoric acid has been demonstrated to be superior to 17% EDTA and 10% citric acid in the apical third of the root canal system.5 (d) Apple vinegar, which consists of malic acid, has been shown to remove the smear layer as efficiently as17% EDTA.6 It has also been shown to be effective against endodontic pathogens.7