In-Vitro Comparison of the Effect of XP-Endo Shaper and One-Shape Rotary Files on the Incidence of Root Dentin Cracks

Root canal preparation with systems with the least chance of dentin cracking can increase the success of endodontic treatment. This study aimed to compare the One-Shape and XP-endo Shaper rotary files in the dentin crack incidence in the mesiobuccal canals of mandibular first molars. Materials and Methods: In this experimental study, 60 eligible extracted mandibular first molars were randomly divided into three groups. The roots were prepared to #30 and 4% taper in the XP-endo Shaper group and #25 and 6% taper in the One-Shape group. The control samples were left intact. All groups were sectioned at 2, 4, and 6mm from the apex and examined under a stereomicroscope at 20× magnification. The incidence, location, and type of cracks were analyzed using chi-square test. Result: There were no cracks in the controls. The crack percentage was 23.33% (n=14) and 11.66% (n=7) in the One-Shape and XP-endo Shaper groups, respectively, with a significant difference with crack-fee samples. There was no significant difference between One-Shape and XP-endo Shaper systems in the three sections (P>0.05). In the 2mm section, cracks were observed in six sections (10%) with One-Shape and four sections (20%) with XP-endo Shaper. In the 4mm section, cracks were observed in one section (5%) with One-Shape and five sections (25%) with XP-endo Shaper. In the 6mm section, cracks were observed in seven sections (35%) with One-Shape and one section (5%) with XP-endo Shaper. Conclusion: The One-Shape and XP-endo Shaper systems were similar in crack incidence in the mesiobuccal canal of mandibular first molars.