Comparison of coronal sealing of flowable composite, resin‑modified glass ionomer, and mineral trioxide aggregate in endodontically treated teeth: An in‑vitro study

Coronal seal is one of the essential factors that affects the success of endodontic treatment and reinforces the apical seal. The intra‑orifice barrier is an efficient alternative approach to decrease coronal leakage in endodontically treated teeth and various materials have been used for this purpose. This study aimed to compare the coronal sealing of flowable composite, resin‑modified glass ionomer (RMGI), and mineral trioxide aggregate (MTA) in endodontically treated teeth.

In this in vitro study, 35 single‑canal canine teeth were divided into five groups, including flowable composite, RMGI, MTA, positive control, and negative control groups. The teeth were filled with restorative materials according to the factory’s instructions. Afterward, the samples were immersed in 2% methylene blue dye solution for 1 week at 37°C and 100% humidity condition. Finally, the teeth were sectioned longitudinally and dye penetration was measured using a stereomicroscope with ×10. Data were analyzed with Kolmogorov–Smirnov and Kruskal–Wallis tests (α = 0.05).

The positive control group showed the highest amount of dye penetration compared to other groups (12.34 ± 0.46). Dye penetration in the MTA group was significantly lower (4.25 ± 0.31) compared to the RMGI group (5.94 ± 0.24) (P = 0.02). Moreover, while the dye penetration in the MTA group was lower than in the flowable composite group (5.65 ± 0.26), the difference was not statistically significant (P = 0.12).

MTA reduces the coronal leakage and provides an acceptable coronal seal in endodontically treated teeth, especially compared to RMGI, and therefore, using MTA as an intra‑orifice barrier increases the endodontic treatment success rate.