Evaluation of coronal leakage of preheated nanohybrid and bulk fill composites in endodontically treated teeth: An in vitro study

Abstract

Aim: The aim of this study was to evaluate coronal leakage of preheated nanohybrid and bulk fill composites in endodontically treated teeth. Materials and methods: A total of 100 human mandibular premolars were divided into six groups after standardized root canal treatment protocol: group I (n = 20): nanohybrid composite (Filtek Z250XT); group II (n = 20): preheated nanohybrid composite; group III (n = 20): bulk fill composite (Filtek Bulk fill); group IV (n = 20): bulk fill composite (Filtek™ Bulk fill); group V (negative control) (n = 10): Gutta-percha was kept intact till orifice and covered with nail polish; and group VI (positive control) (n = 10): Gutta-percha was kept intact till orifice. The samples were thermocycled followed by dye penetration with 2% methylene blue. Scoring was done under stereomicroscope at 10× magnification. Kruskal–Wallis test, Wilcoxon signed-rank test, and Mann–Whitney U test were applied. There was significant difference among all the groups. Results: Preheated bulk fill composites sealed significantly better. Nanohybrid composites displayed the highest microleakage followed by preheated nanohybrid composite. Bulk fill composites were better than preheated nanohybrid composites. Conclusion: Preheating decreases microleakage of nanohybrid and bulk fill composites. Bulk fill composites, especially when preheated, are superior in performance to nanohybrid composites in terms of microleakage. Clinical significance: Preheated bulk fill composites are a suitable alternative to nanohybrid composites for the improvement of marginal integrity of restorations in endodontically treated teeth.