Comparison of the efficacy of ethylene diamine tetraacetic acid and maleic acid in the removal of three calcium hydroxide intra-canal dressings: A spiral computerized tomography volumetric analysis

AIM: To assess the efficacy of 17% ethylene diamine tetra acetic acid and 7% maleic acid in the removal of 3 calcium hydroxide preparations placed as intracanal medicaments. MATERIALS AND METHODS: The root canals of 60 single rooted premolars were prepared with a step back technique and randomly assigned into 3 experimental groups (n= 20). Group A was filled with plain calcium hydroxide mixed with distilled water in which barium sulfate was added for radio opacity, Group B was filled with Apexcal and Group C was filled with Metapex. After 7 days each group was divided into 2 sub groups (n= 10). The medicaments were retrieved with 17% EDTA (first sub group) and 7% maleic acid (second sub group). Along with the above irrigants manual and ultrasonic agitation was used. The pre and post removal volume of medicaments in root canals were measured using spiral computerized tomography. The percentage difference was calculated and statistically analyzed using Kruskal Wallis and Mann Whitney U test. RESULTS: 17% EDTA and 7% maleic acid efficiently removed calcium hydroxide, distilled water mixture (P= 0.218) and Apexcal (P= 0.684), whereas 7% maleic acid showed better retrieval capability of Metapex than 17% EDTA (P= 0.002). CONCLUSION: Calcium hydroxide, distilled water mixture and polyethylene glycol based calcium hydroxide were efficiently removed by 17% EDTA and 7% maleic acid. 7% maleic acid removed silicone oil based calcium hydroxide preparation better than 17% EDTA.