The influence of the apical limit of root canal preparation on apical foramen transportation (laboratory study)

Objective: This study was conducted to evaluate the effect of apical terminus location of the root canal preparation on apical transportation in vitro. Materials and Method: Thirty extracted human maxillary first molars with mature apices were used. The mesiobuccal root of each tooth was mounted in a square piece of silicone leaving foramen on top. The specimens were randomly divided into 3 groups according to the apical limit of root canal preparation (flushed with apical foramen, 0.5 and 1 mm away from the apical foramen). Initial and final photographs of apical foramen were taken before and after instrumentation using a stereomicroscope. The images of each specimen (pre and post) were superimposed to determine transportation. Results: Results demonstrated that termination of the root canal preparation flushed at the apical foramen showed the highest transportation with statistically significant difference in comparison to the other two groups. Conclusion: No statistically significant difference was found comparing termination of the root canal preparation 0.5 mm or 1mm away from the apical foramen.