Effect of Root Canal Transportation by Minimally Invasive Endodontic Shaping of Canal Orifice Dentin

抄録

 Background: The purpose of this study was to analyze the effect of minimally invasive (MI) shaping of canal orifice dentin by evaluating the shaping characteristics of TruNatomy (TN), which was developed as a Ni-Ti file capable of MI endodontics.

 Methods: A J-shaped canal model was used to compare prepared final canal morphology using a minimally invasive shaping TN file and a conventional shaping ProTaper NEXT (PTN) file. The TN files used in the experiment were classified into two groups: no straight-line access (group A) and straight-line access (group B). The PTN files of the control were also classified into two groups: no straight-line access (group C) and straight-line access (group D), and the increase in canal width and the median displacement (transportation) were compared.

 Results: Analysis of the canal width by TN showed that the displacement on the inner side increased by 5 mm in both groups A and B, but the displacement on the outer side increased at the other measurement sites. In groups C and D using PTN, the displacement on the inner side increased by 3-5 mm. On the other hand, the displacement on the outer side increased by 8 mm, and the displacement in group D increased. The canal transportation using TN was 0.1 mm or less in both groups A and B, although preparation by PTN showed significant transport to the inner side by 3-5 mm and outer side of 8 mm in group D compared to groups A and B.

 Conclusion: TN shaping was shown to preserve tooth structure and canal geometry without straight-line access. It was confirmed that TN, which was developed based on the concept of MI Endo, enables accurate root canal shaping and reduces transportation.