Abstract
OBJECTIVE: The aim of the study is to assess the fracture resistance of roots with simulated internal resorption defects with perforations, repaired with various calcium-silicate cements, and obturated with hybrid obturation technique. MATERIALS AND METHODS: Ninety-six human single-rooted mandibular premolar teeth were included in the study. Twelve intact roots were assigned as the negative control group. Uniform internal resorption cavities were created in the middle section of the roots. The positive control group (n = 12) comprises a root with a resorption cavity, instrumented but not filled. The remaining 72 teeth were randomly divided into six experimental groups (n = 12) each according to the obturation technique and repair method used. Group 1 - Mineral trioxide aggregate (MTA) + MTA; Group 2 - MTA + gutta-percha (GP) + AH Plus; Group 3 - MTA + GP + MTA Fillapex; Group 4 - Biodentine + Biodentine; Group 5 - Biodentin + GP + AH Plus; Group 6 - Biodentin + GP + MTA Fillapex. Specimens embedded in acrylic resin were exposed to vertical compressive loading at a rate of 1 mm/min. Statistical analysis was done with one-way analysis of variance, post hoc Tukey test, Honestly Significant Difference, and Bonferroni test. RESULTS: Group 4 exhibited statistically higher resistance to fracture, whereas Group 3 showed the lowest (P < 0.05). Group 2 showed greater fracture resistance than Group 3, and Group 5 had higher fracture resistance than Group 6. The positive control group had significantly lower fracture resistance than Groups 1 and 4 (P < 0.05), whereas the negative control group demonstrated significantly higher fracture resistance than all groups using GP and sealer combinations (P < 0.05). CONCLUSION: Calcium silicate cement can provide the tooth structure with more strength than backfilling with the combination of GP/sealer.