Effect of endodontic solvents on the push-out bond strength of premixed bioceramic sealer to root dentin: an in vitro study

This study aimed to evaluate the effect of two gutta-percha solvents on the push-out bond strength of bioceramic sealer to root dentin. Forty-five extracted human single-rooted premolars with single canals were instrumented using the ProTaper Universal system and randomly assigned to three groups ( n = 15): Endosolv, orange oil, and no-solvent (control). After 5-min solvent application and irrigation, canals were obturated with gutta-percha and TotalFill bioceramic sealer using the cold lateral compaction technique. Roots were sectioned horizontally and push-out bond strength was measured with a universal testing machine at a crosshead speed of 0.5 mm/min. Data were analyzed using ANOVA, Bonferroni tests, and linear mixed-effects model (α = 0.05). The orange oil group showed significantly lower bond strength than the Endosolv and control groups ( P < .05), whereas no difference was observed between Endosolv and control. Bond strength increased from the coronal to apical thirds ( P < .05) and showed a strong negative correlation with canal lumen diameter ( r = − 0.976 to − 0.995, P < .001). Failure analysis revealed mainly cohesive failures in the control group and mixed failures in orange oil group. These findings indicate that orange oil significantly reduces the adhesion of the tested bioceramic sealer, whereas Endosolv has minimal influence.