An In Vitro Comparison of the Sealing Ability of Three Endodontic Sealers Used in Canals with Iatrogenic Enlargement of the Apical Constriction

In cases of disrupted apical constriction effort is made to create an apical stop and subsequently instrument and obturate the canal up to this point. The aim of this study was to in vitro evaluate the sealing ability of three root canal sealers used with the lateral compaction technique in teeth with enlarged constriction. Thirty-six single rooted premolars with straight canals were instrumented up to the apical constriction using a step-back technique. The constriction was enlarged and root canal instrumentation 1.5 mm short of the original working length was performed, to create a new apical stop. Teeth were obturated using lateral compaction technique with either Topseal, Roth 811, or Apexit. Teeth were subjected to area-metric analysis of dye penetration in transverse root sections, up to the most coronal extend of the dye. Sections were studied under the stereomicroscope, digital images were processed and leakage area was estimated. Statistical analysis was performed using Student's t test and Wilcoxon matched-pairs signed-rank test. No gutta-percha was extruded into the space between the apical constriction and the new iatrogenically created constriction. Topseal showed statistical significant less leakage. No significant difference was found between Apexit and Roth 811 (t = 0.99; p = 0.75).