2023 Volume 3 Issue 1 Pages 113-120
Purpose: The purpose of this study was to evaluate the effects of the ProTaper Ultimate (PTU), which has a new design based on integrated technology, on preparation ability in simulated curved root canals compared with previous gold wire-based nickel titanium rotary file systems.
Methods: The surfaces of J-shaped simulated root canals in clear resin blocks were scanned as image files. The working length was defined as the root canal length minus 1 mm. The negotiation of all root canals was confirmed with a stainless steel #10 K-file. The blocks were divided into three groups of 10 each (PTU, ProTaper Gold [PTG], and WaveOne Gold [WOG]) and randomly prepared through size #25. The inner and outer displacements of the root canal wall were measured from superimposed images before and after preparation. In addition, the working times of each group and process were measured. The Kruskal-Wallis test followed by the Steel-Dwass test were used for all comparisons and statistical analyses.
Results: Regarding root canal wall displacement, no significant difference was observed in all groups at 1 mm and 2 mm from the root canal apex, except for 1 mm on the inner side of the curvature (p＜0.05). At 3 mm and 4 mm from the root canal apex, the root canal wall displacement of PTU was significantly smaller than those of PTG and WOG in the inner side of the curvature, while it was significantly larger in the outer side of the curvature (p＜0.05). PTU prepared the inner and outer sides most evenly among the three groups. The total working time and the root canal wall shaping time in each group were longer in the order of WOG＜PTU＜PTG. Both times were significantly different among the three groups (p＜0.01). In addition, PTU had the smallest variance and preparation took almost the same amount of time even when the experiment was performed multiple times. On the other hand, there was no significant difference between groups in the time required for glide path preparation.
Conclusion: The curved root canals at the measurement points were prepared most evenly by PTU in this study. Also, the total working time and the root canal wall shaping time were significantly reduced with PTU compared to PTG, and both times of PTU were close to the measurement time of WOG.
