Department of Endodontics, Dental School, Hamadan University of Medical Sciences, Hamadan, Iran.
, Hamadan, Iran.
BMC Oral Health. 2021 May 25;21(1):277. doi: 10.1186/s12903-021-01617-w.
Cleaning and shaping of the root canal system is an important step of endodontic treatment. Canal transportation is a common procedural error in preparation of curved canals. This study aimed to compare the canal transportation and centering ratio of two rotary files in curved canals using cone-beam computed tomography (CBCT).
Forty-four extracted human mandibular first molars with mature apices and 10° to 30° apical curvature were selected. The samples were randomly divided into two groups (n = 22) with similar curvature. The canals were prepared with ProTaper and XP-endo Shaper file systems according to the manufacturers' instructions. The CBCT images were obtained using Cranex 3D CBCT scanner before and after root canal preparation, and canal transportation and centering ratio of the files at 3, 4 and 5 mm levels from the apex were calculated. Data were compared between the two groups using independent t-test at 0.05 level of significance.
The ProTaper Universal caused greater canal transportation and had lower centering ratio than XP-endo Shaper in both mesiodistal and buccolingual directions at all levels from the apex. The difference between the two groups regarding canal transportation was significant at all levels from the apex in buccolingual direction (P < 0.05) except for 3 mm from the apex (P > 0.05). The difference between the two groups regarding centering ratio was not significant (P > 0.05) in mesiodistal direction at all levels except for 4 mm from the apex (P < 0.05).
The ProTaper Universal causes greater canal transportation in both buccolingual and mesiodistal directions than XP-endo Shaper.
根管系统的清洁和成形是牙髓治疗的重要步骤。根管偏移是弯曲根管预备中常见的程序性错误。本研究旨在使用锥形束 CT（CBCT）比较两种旋转锉在弯曲根管中的根管偏移和中心度比。
选择 44 颗具有成熟根尖和 10°至 30°根尖弯曲的下颌第一磨牙。将样本按相似的曲率随机分为两组（n=22）。根据制造商的说明，使用 ProTaper 和 XP-endo Shaper 锉系统预备根管。使用 Cranex 3D CBCT 扫描仪在根管预备前后获得 CBCT 图像，并计算根尖 3、4 和 5mm 处文件的根管偏移和中心度比。使用独立 t 检验在 0.05 水平比较两组间的数据差异。
在根尖各水平，ProTaper Universal 在颊舌向和近远中向引起的根管偏移均大于 XP-endo Shaper，且中心度比均较低。在颊舌向，除根尖 3mm 处外（P>0.05），两组间的根管偏移在各水平均有显著差异（P<0.05）。除根尖 4mm 处外（P>0.05），两组间的中心度比在近远中向各水平均无显著差异（P>0.05）。
与 XP-endo Shaper 相比，ProTaper Universal 在颊舌向和近远中向引起的根管偏移更大。
