Comparative Evaluation of the Sealing Ability of Root Canal Sealers: An In Vitro Study Using Dye Penetration and Scanning Electron Microscopic Analysis

Abstract

INTRODUCTION: Achieving an impervious seal in root canal treatment is crucial for preventing bacterial infiltration and ensuring long-term success. Various root canal sealers are available, each with different compositions and sealing abilities. This in vitro study aimed to compare the sealing abilities of four different root canal sealers using dye penetration and scanning electron microscopy (SEM). METHODS: Sixty-two extracted single-rooted human teeth were prepared using a standardized rotary instrumentation technique. One tooth served as the positive control, and one tooth served as the negative control. The remaining 60 samples were randomly divided into four experimental groups. In Group 1 (n = 15), gutta-percha (Dentsply Maillefer, Ballaigues, Switzerland) was used in conjunction with Tubli-Seal (SybronEndo, Orange, California). In Group 2 (n = 15), gutta-percha was used in conjunction with AH Plus (Dentsply Maillefer). In Group 3 (n = 15), gutta-percha was used in conjunction with RealSeal SE (SybronEndo). In Group 4 (n = 15), gutta-percha was used in conjunction with SmartPaste Bio (Smartseal DRFP Ltd., Stamford, UK). The samples were obturated using the cold lateral condensation method. After obturation, 10 teeth in each group were evaluated for microleakage using the dye penetration method, and five teeth from each group were examined under SEM to analyze the adaptation of the sealers to the dentinal walls. The data were statistically analyzed. RESULTS: The mean dye penetration values were significantly different between groups (P < 0.05). Group 1 showed the highest mean dye infiltration (9.30 ± 1.75 mm), followed by Group 2 (6.80 ± 1.21 mm), Group 3 (4.70 ± 0.89 mm), and the least in Group 4 (2.15 ± 1.16 mm). SEM analysis further confirmed that Group 1 had the highest mean microgap (18.44 ± 4.98 µm), followed by Group 2 (12.90 ± 2.81 µm), Group 3 (9.41 ± 3.51 µm), and the least in Group 4 (2.65 ± 2.07 µm). CONCLUSION: The findings suggest that the sealing ability of root canal sealers varies significantly, with SmartPaste Bio demonstrating the best performance in terms of microleakage and adaptation to the dentinal walls. Clinicians should consider the choice of sealer as a critical factor in achieving an optimal apical seal. Further in vivo studies are required to validate these results and determine their clinical implications.