Efficacy of Different Solvents in Re-achieving Apical Patency After Obturation with a Calcium Silicate-based Root Canal Sealer

Objectives: This study aims to evaluate the efficacy of different solvents in dissolving and retrieving a calcium silicate-based root canal sealer, BioRoot RCS (Septodont, Saint-Maurdes-Fossés, France). Materials and Methods: 110 mandibular premolars were instrumented and obturated with BioRoot RCS and single cone gutta-percha (GP) placed to the working length (group WL) or 2 mm short of the WL (group WL-2mm). Retreatment of canals was performed using rotary instruments, hand files and one of the following solvents (n=10): chloroform, xylol, eucalyptol, orange oil, endosolv or no solvent (n=5) as a control group. The ability to reachieve apical patency was evaluated. Next, 60 standardized stainless steel rings were used as molds for BioRoot RCS placement. The sealer molds were divided into 12 groups (n=5) and immersed in 10 ml of each solvent and distilled water as a control group, at 2 immersion periods (3 and 10 minutes). The percentage of sealer’s weight loss pre- and post-immersion was calculated. Data were statistically analyzed with the chi-square, Fisher exact, KruskalWallis on ranks, and Wilcoxon tests. Results: No significant difference was found between all tested solvents and the control group in terms of re-achieving apical patency and the ability to dissolve BioRoot RCS (p>0.05). Conclusions: Re-achieving apical patency after obturation with BioRoot RCS is not a predictable procedure and will mainly rely on the mechanical action of endodontic instruments. Keywords: Calcium silicate-based sealers, Obturation, Organic solvents, Retreatment, Solubility.