Apical Transportation of Mesiobuccal Canals of Maxillary Molars Following Root Canal Preparation with Two Rotary Systems and Hand Files: A Cone-Beam Computed Tomographic Assessment

Abstract

Objectives: This study aimed to compare the transportation of the mesiobuccal canal of maxillary molars following root canal preparation with HyFlex CM (HCM) and Edge Taper Platinum (ETP) rotary systems and stainless steel (SS) hand files using cone-beam computed tomography (CBCT).
 Materials and Methods: This in-vitro study was performed on 48 maxillary molars in three groups of 16. The teeth were mounted in acrylic blocks, and root canals were prepared using HCM in group 1 (up to #30/0.06), ETP in group 2 (up to F3/0.06), and SS hand files in group 3 (up to #30). CBCT scans were taken before and after root canal preparation. The amount of canal transportation was measured at 0, 3, 6, and 9mm from the apex. Data were analyzed using Kruskal-Wallis and Mann-Whitney tests.
 Results: The difference in canal transportation at 0 and 6mm from the apex was significant between the HCM and ETP groups (P=0.031 and 0.023) but none of the systems showed any significant difference with hand files at 0- and 6-mm levels (P=0.10, 0.56, 0.22, and 0.50), respectively. At 3mm from the apex, no significant difference was noted among the groups (P=0.30). At the 9-mm level, the amount of canal transportation was not significantly different between HCM and ETP (P=0.83) but they showed significant differences with hand files (P<0.001).
 Conclusion: ETP and HCM caused less canal transportation at the curvature of the mesiobuccal canal of maxillary molars compared to hand files. ETP showed superior efficacy in root canal preparation compared to HCM.

Letter to the Editor, “Apical Transportation of Mesiobuccal Canals of Maxillary Molars Following Root Canal Preparation with Two Rotary Systems and Hand Files: A Cone-Beam Computed Tomographic Assessment”

“…We read with great interest the article by Sarraf et al [ 1 ], which follows the great goal of evaluating the efficacy of rotary files. This study used HyFlex CM and Edge Taper Platinum rotary systems and stainless-steel hand files for root canal preparation of the mesiobuccal canal of maxillary molars and compared apical transportation among these systems.…”

“…This is followed by application of Ethylenediaminetetraacetic acid solution or gel. However, Sarraf et al [ 1 ] used a single-length technique for canal preparation, which did not comply with the manufacturer’s instructions for proper use.…”

“…The authors mentioned that minimum transportation occurred three millimeters from the apex, due to a straight pathway of the canal [ 1 ], which does not seem logical. Curvature mainly starts from the mid-portion of a maxillary molar’s mesiobuccal root ( Figure 1 ) and the smaller part of the file has more tendency to retain its primary form which causes more transportation.…”

“…They presented the mean values of 60, 70, and 90µm transportation in three, six, and nine millimeters from the apex of curved mandibular mesiobuccal canals, respectively. It would have been better if the authors [ 1 ] had compared their results with similar studies, and explained the differences and expressed their reasons.…”