Comparative evaluation of 4 root-end filling materials sealing ability in an in-vitro study

The aim of this study is to evaluate and compare the marginal adaptation of four retrograde filling materials by micro-infiltration of basic dye and related analysis with stereomicroscope. Forty human teeth extracted with single-channel roots were selected for the study. The root canals were first instrumented and filled with gutta-percha and endodontic cement. Subsequently the root apices underwent apicectomy and 3 mm deep retrograde cavities were prepared. The teeth, divided into four groups, were filled with four different retrograde filling materials assigned to the specific group and subsequently treated with basic dye solution ( Methylene blue ) for the determination of micro-infiltrations. The apical portions of the study teeth were cut to 1 mm and 2 mm to obtain cross-sections to be analyzed with the stereomicroscope. The dye, infiltrated in the vacuum areas (gaps) between dentin and retrograde filling cement, shows the marginal filling materials adaptation with the dental surface in retrograde techniques. The statistical analysis showed, with statistically significant values, fewer internal voids, and therefore greater marginal adaptation with Biodentin and Aureoseal, compared to ProRoot MTA and MTA Flow.