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Comparison of apical transportation and centering ratio between Bassi Logic and Protaper-Next NiTi rotary systems in
Maryam Khalili1, Abbas Shokri2, Hamed Karkehabadi3
1Department of Endodontics, Faculty of Dentistry, Hamadan University of Medical Sciences, Hamadan, Iran.
Background:
Preservation of the original root canal anatomy is essential for the long-term success of endodontic treatment. Effective cleaning and shaping of the root canal system are critical steps in this process; however, canal transportation is a common procedural error during the preparation of curved canals. This study aimed to compare canal transportation and centering ability between two rotary file systems, ProTaper Next and Bassi Logic, in curved root canals using cone-beam computed tomography (CBCT).
Methods:
Forty extracted human mandibular first molars with mature apices and an apical curvature ranging from 10° to 30° were selected. These samples were randomly allocated into two groups of 20 teeth, ensuring similar average curvatures. Root canal preparation was performed using either the ProTaper Next or Bassi Logic rotary file systems, strictly adhering to the manufacturers' protocols. CBCT images were acquired using a Kodak 9600 system (Care Stream, Paris, France), both before and after instrumentation. Canal transportation is a common procedural error during the preparation of curved canals. Statistical analysis was performed using an independent t-test to compare the two groups, with the significance level set at P < 0.05. Statistical analysis was performed using an independent t-test, with the significance level set at P < 0.05.
Results:
The ProTaper Next system demonstrated greater canal transportation and a lower centering ratio across all evaluated apical levels compared to the Bassi Logic system. Statistically significant differences in canal transportation were observed at the 3 mm level in the mesiodistal plane and at the 5 mm level in the buccolingual direction (P < 0.05). However, no statistically significant differences in centering ratio were found between the two systems at any of the evaluated levels (P > 0.05).
Conclusions:
Within the limitations of this in vitro study, both systems demonstrated acceptable shaping ability in curved canals; however, Bassi Logic showed less canal transportation at certain apical levels, which may support better preservation of canal anatomy in clinical practice.
