In vitro Comparative Evaluation of the Fracture Resistance of Simulated Immature Teeth

Aim: This study aimed to assess and compare the fracture resistance of simulated immature teeth reinforced with Biodentine (BD) and mineral trioxide aggregate (MTA) as apical barriers and two root canal backfilling combination (gutta-percha/AH26, MetaSeal). Materials and methods: A total of 70 extracted human maxillary incisors were randomly divided into seven groups (n = 10). The positive control group was not instrumented. For the other groups, coronal access was made and root canals were instrumented using the ProTaper, up to F5 followed by six Peeso reamers which were allowed to pass 1 mm beyond the apex to size 6 (1.7 mm) to simulate immature teeth. The apical 4 mm of their root canals was filled with either MTA or BD apical barrier, then backfilled with gutta-percha/AH26 or MetaSeal obturation combination. The negative control group was left unfilled. Composite resin was used to restore the coronal access cavities. The maximum load for fracture of each tooth was recorded utilizing a universal testing machine. Data were analyzed using two-way analysis of variance. Results: The noninstrumented group I had the highest fracture resistance and differed significantly (p < 0.05) from the negative control groups. On the contrary, no significant difference was found between BD and MTA groups, regardless of the backfilling combination (p > 0.05). Conclusion: There was no difference between MTA and BD apical barriers and the backfilling combination regarding their resistance to root fracture.