Effect of obturating materials on fracture resistance of simulated immature teeth

The aim of this study was to evaluate the fracture resistance of simulated immature teeth, when the root canals were completely filled either with mineral trioxide aggregate (MTA) or Biodentine, comparing with that of roots filled with apexification procedure. Sixty mandibular premolar teeth with single, straight canals decoronated at cementoenamel junction were divided into five groups ( = 12 each). Group 1 samples served as negative control and remaining four groups root samples were shaped and cleaned using ProTaper rotary files. To simulate immature roots, a #5 Peeso reamer was passed beyond the apex so that apices were enlarged to a diameter of 1.5 mm. Group 2 and 4 samples were filled with 5 mm of MTA or Biodentine apical plug and backfilling with gutta-percha using AH Plus sealer. Group 3 and 5 root samples were completely obturated with MTA and Biodentine, respectively. All the teeth were loaded vertically until fracture, using the universal testing machine. Forces at which fracture of the roots occurred were subjected to statistical analysis using SPSS/PC version 2 software, and the results were analyzed with the one-way analysis of variance and Newman-Keuls multiple test. Complete root canal obturation with MTA or Biodentine has shown significantly higher fracture resistance ( < 0.05) when compared to apexification with MTA or Biodentine. Obturation of the root canals with bioactive materials has shown highest fracture resistance when compared to apexification groups.