Efficacy of alendronic acid solution in removal calcium hydroxide from root canals

Intracanal medication is considered an alternative after instrumentation in the case of pulp necrosis. However, the elimination of this medication plays an important role in the obturation process, which is why various chelating solutions have currently been studied for this purpose. Therefore, this study aimed to analyze the irrigant based on alendronic acid (AA), which contains in its chemical structure functional groups capable of forming complexes with Ca2+ ions. 90 single-rooted teeth were crowned and standardized to a length of 13 mm. They were instrumented with a progressive K file (Dentsply Maillefer) from #15 to #30. Ca(OH)2 was placed as intracanal medication for 7 days. The roots were randomly divided into the following 4 experimental groups (n=13) according to the irrigant used: 2.25% NaClO, calcium suspension, 0.22% AA, and 10% citric acid; as well as negative (n=5; saline solution) and positive controls (n=5, 17% EDTA). The roots were divided longitudinally and the % of permeable dentinal tubules (% PDT) was determined by thirds (cervical, middle and apical), by analyzing the micrographs obtained by scanning electron microscope (SEM) and the imageJ program. The quantification of the remaining Ca2+ was determined using the Arsenazo III technique. The Kruskal Wallis test was used for the % of permeable dentinal tubules where a significant difference was determined for the different thirds (