Efficacy of different irrigation solutions and techniques for removing intracanal medicaments used in regenerative endodontics: An in vitro study

Purpose: This study assessed the efficacy of various irrigation solutions (EDTA, EDTA with benzalkonium chloride [BAC], ethanol, and glycolic acid) and techniques (conventional needle irrigation, sonic, and ultrasonic systems) for removing calcium hydroxide Ca(OH)2 and double antibiotic paste (DAP) medicaments.
Methods: Ca(OH)2 and double DAP were placed in the canals of extracted single rooted human mandibular premolars. The specimens were divided into groups based on the irrigation solutions and techniques (conventional needle irrigation, sonic and ultrasonic activation) used. After removal of the medicaments, residues were evaluated using stereomicroscope. The Mann-Whitney U, the Kruskal-Wallis and by Dunn-Bonferroni post hoc tests were used to analyze the data.the study results at a 95% confidence level.
Results: The lowest residue scores were observed with 17% EDTA and 17% EDTA with BAC, regardless of irrigation techniques for Ca(OH)2, and with 17% EDTA, 17% EDTA with BAC, and ethanol for DAP (p<0.05). The highest scores were obtained with 10% glycolic acid. The methods of irrigation showed similar effectiveness in each solution group.
Conclusion: EDTA and EDTA + BAC solutions provided the lowest residue scores, confirming EDTA’s effectiveness regardless of the irrigation method. While BAC or ethanol may enhance intracanal medication removal, glycolic acid likely caused precipitation, leading to higher scores.

Keywords: Calcium hydroxide, double antibiotic paste, benzalkonium chloride, glycolic acid; ethanol.