Comparison of Transportation within Reciproc and Neolix Rotary Systems in Curved Root Canals Using Cone Beam Computed Tomography

The preparation of the root canal (i.e., cleaning and shaping) is the main step in the endodontic treatment. The nickel-titanium rotary files result in fewer errors during the preparation of curved canals. This study aimed to compare the transportation of Neolix and Reciproc rotary systems in curved canals using cone beam computed tomography (CBCT). In this experimental study, 70 extracted curved premolar teeth from patients referred to dentistry faculty were assigned  into two groups (n=35). The preparation of the canals was performed by the Neolix and Reciproc rotary systems. Remaining dentin thickness, transportation, and canal-centering ratio were evaluated and compared using CBCT images before and after the instrumentation. The data were analyzed in SPSS software (version.19) through ANOVA, independent t-test, and paired t-test. There was a significant difference in terms of remaining dentin thickness in three sections of 3, 5, and 7 mm from the apex, before and after the instrumentation regarding the level of mesiodistal and buccolingual. However, no significant difference was observed in terms of the transportation in three sections of 3, 5, and 7 mm from the apex in both Neolix and Reciproc systems. According to the results, both Neolix and Reciproc rotary systems showed high efficacy in root canal shaping. The amount of transportation in these systems during preparation of curved canals was very low leading to the protection of canal-centering ratio.