Comparative evaluation of removal of oil-based calcium hydroxide intracanal medicaments with two calcium chelators: An in vitro cone-beam computed tomography volumetric analysis

Background: Intracanal medicament (ICM) eliminates remaining bacteria and their toxins that were not removed by chemomechanical preparation during endodontic treatment.

Aim: The aim of this study was to compare and evaluate the removal of ozonated oil-based, silicone oil-based, and distilled water-based ICM with two calcium chelators, i.e., 0.2% chitosan and 17% ethylenediaminetetraacetic acid (EDTA).

Materials and methods: A total of 54 mandibular permanent premolars were included and randomly allocated into 3 groups after cleaning and shaping along with thorough irrigation. Group 1 - ozonized calcium hydroxide group; Group 2 - Metapex group; Group 3 - Ca(OH)₂ with distilled water group. Using an irrigant for removal, the teeth in each group were distributed at random to two subgroups - (A) 0.2% chitosan solution; (B) 17% EDTA solution. All the samples were ultrasonically agitated and the volume remaining in each tooth after retrieval was estimated using additional cone-beam computed tomography scans. The result was analyzed using one-way analysis of variance, following post hoc Tukey test.

Results: The mean percentage of ozonized Ca(OH)₂, aqueous calcium hydroxide, and Metapex removed by 0.2% chitosan had greater values in comparison to 17% EDTA. When eliminating aqueous-based calcium hydroxide, both chelators showed similar effectiveness (P > 0.05). In contrast, 0.2% chitosan outperformed 17% EDTA in retrieving oil-based Ca(OH)₂ (P < 0.05).

Conclusion: The aqueous-based form of Ca(OH)₂ was removed more easily compared to the oil-based form. A combination of 0.2% chitosan and ultrasonics proved to be more effective than 17% EDTA in eliminating oil-based calcium hydroxide.