ABSTRACT
Background and Aim: Application of a retrograde filling material in a cavity prepared in root-end through endodontic surgery has great importance to provide apical seal and prevent bacterial penetration. Therefore, The aim of this in vitro study was to compare the sealability of Gray-colored Portland Cement [GPC], White-colored Mineral Trioxide Aggregate [WMTA], and [Sealapex] with addition of Zinc Oxide [ZnO] when used as retrograde filling materials to investigate which of these materials has the best apical sealability. Materials and Methods: The sample of study consisted of sixty recently extracted, single-rooted, permanent human teeth. The root canals were prepared using Crown-Down technique and obturated with laterally condensed gutta-percha points and zinc oxide-eugenol sealer, then the coronal restorative material [GIC] was placed. After that, [2-3 mm] of each root apex was sectioned at 45° angle, the apical cavities with the depth of [2-3 mm] were performed for the retrograde filling, then the sample was randomly divided into 3 equal groups of 20 teeth each, according to the retrograde filling material used: /[Group1: [GPC], Group2: [WMTA], Group3: [Sealapex + ZnO]/]. After retrograde filling, the apical sealability was assessed by immersion in 2% methylene blue dye [100% humidity at 37°C] for 24 hours. The teeth were sectioned longitudinally in a buccolingual direction, then the extent of dye penetration was examined by a stereomicroscope [20X magnification]. Results: Kruskal-Wallis, one-way ANOVA, and Bonferroni tests were used, it showed that [WMTA] was the best retrograde filling material as an apical sealing [P<0.05] material. There was a statistically significant difference in the mean of apical dye leakage between [WMTA] and [GPC]. The next material was [Sealapex + ZnO], but there was no statistically significant difference in the mean of apical dye leakage between it and [WMTA]. The last material was [GPC], but also there was no statistically significant difference in the mean of apical dye leakage between it and [Sealapex + ZnO]. Conclusions: [WMTA] is a promising material as an apical sealing material used in retrograde filling, it has an apical sealability better than other materials used in this study, and [GPC] can not be used in a retrograde filling. KeyWords: Apical sealability, Retrograde filling, PC, MTA, Sealapex
ABSTRACT
The quality of root canal filling is considered the key of the successful endodontic treatment, because the one of goals of root canal obturation is to obtain three-dimensional and complete sealing. Therefore, The aim of this in vitro study was to evaluate the quality of root canal filling of White-colored Mineral Trioxide Aggregate [WMTA] and Gray-colored Portland Cement [GPC]. The sample of study consisted of seventy five recently extracted, single-rooted, permanent human teeth. The root canals were prepared using Crown-Down technique, then the sample was randomly divided into 5 equal groups of 15 teeth each, according to the root canal filling material used: [Groupl: [WMTA] lonely, Group2: [GPC] lonely, Group3: [Gutta-percha points + WMTA], Group4: [Gutta-percha points + GPC], GroupS: [Gutta-percha points + AH26]]. After root canal filling, the temporary coronal restorative material [Coltosol F] was placed, and the teeth were stored in [100% humidity at 37°C] for 7 days. Then, it were cleared and examined by a stereomicroscope [20X magnification] to evaluate the presence of the filling cement in the apical, middle, and coronal thirds of the root canal. Kruskal-Wallis and Mann-Whitney U tests were used, it showed that [GPC] lonely achieves the best quality of root canal filling in the middle thirds, whereas, it was the worst material in the apical thirds. There were no statistically significant differences among the five groups of used materials in the coronal thirds. In the root canal filling [WMTA] lonely, [Gutta-percha points + WMTA], [Gutta-percha points + GPC], and [Gutta-percha points + AH26] can be used, but [GPC] lonely can not be used