Effect of post space preparation on apical seal: influence of time interval and sealer

To assess the efficacy of two sealants to preserve the apical seal after root canal preparation and cementation of posts at 24 h or 72 h after endodontic treatment.

Sixty human single-root teeth were instrumented and obturated using lateral compaction technique with EndoFill [30] or AH-Plus) [30] and were prepared in one of three ways, leaving a 3 mm gutta percha remnant in all cases: without cast post preparation, with preparation after 24 h or after 72 h. After cementing the posts, the specimens were thermal cycled at 5 and 55 degrees C in water baths, submerged in 2% methylene blue dye for 72 h, embedded in acrylic resin and cut transversally into three 1-mm apical sections. Dye leakage was quantitatively assessed as the percentage leaked area.

Comparison of the apical sections showed significant differences in leakage with both sealers among the three preparation groups (p<0.001). No significant differences between sealers were found in any preparation group or in the same sections.