Aim To assess the apical sealing ability of two root-end filling materials in extracted teeth by means of a fluid filtration system and a preliminary microtomographic analysis. Methodology The crowns of twenty-four single-rooted freshly extracted caries-free teeth were removed. Electronic working length was determined making use of an alginate-based model. Canals were instrumented with Mtwo rotary files (Sweden & Martina, Italy), irrigated with 5% NaOCl, dried and filled with thermoplasticized gutta-percha (System B; SybronEndo, USA). Under constant water irrigation, three mm of the root apices were resected and root-end cavities were prepared with ultrasonic tips. Two experimental groups (n = 10) were defined: root-end cavities were filled with: Group 1 (G1) – SuperEBA (Bosworth, USA); Group 2 (G2) – MTA (Dentsply Maillefer, Switzerland). Four roots served as positive and negative controls. The specimens underwent a fluid filtration test by the method of Cobankara et al. (2002), during which leakage was measured at multiple time intervals. Collected data were subjected to non-parametric analysis (P < 0.05). Microtomographic scans of two specimens per group were acquired. Results Final filtration values (lL) were: G1, 0.087 ± 0.052; G2, 0.083 ± 0.054. The difference in terms of leakage was not statistically significant. As a general trend, an extended exposure to fluid pressure led to significantly increased leakage values, although this increase tended to diminish with time. Limited void volumes were detected in both experimental groups through microtomographic analysis; they were distributed inside the filling materials and along the canal walls. Conclusions Within the limitations of this ex vivo study, root-end cavities filled with SuperEBA and MTA exhibited similar apical seal. The root canal filling materials could not entirely fill the canal space in any scanned specimen. The relation between voids distribution/amount and sealing ability is still unclear.
