Department of Endodontics, Arthur A. Dugoni School of Dentistry, University of the Pacific, San Francisco, California 94115, USA.
J Endod. 2011 Jan;37(1):53-7. doi: 10.1016/j.joen.2010.08.047. Epub 2010 Oct 8.
The aim of this study was to describe the canal shaping properties of a novel nickel-titanium instrument, the self-adjusting file (SAF), in maxillary molars.
Twenty maxillary molars were scanned by using micro-computed tomography at 20-μm resolution. Canals were shaped with the SAF, which was operated with continuous irrigation in a handpiece that provided an in-and-out vibrating movement. Changes in canal volumes, surface areas, and cross-sectional geometry were compared with preoperative values. Canal transportation and the fraction of unprepared canal surface area were also determined. Data were normally distributed and compared by analyses of variance.
Preoperatively, mean canal volumes were 2.88 ± 1.32, 1.50 ± 0.99, and 4.30 ± 1.89 μm(3) [corrected] for mesiobuccal (MB), distobuccal (DB), and palatal (P) canals, respectively; these values were statistically similar to earlier studies with the same protocol. Volumes and surface areas increased significantly in MB, DB, and P canals; mean canal transportation scores in the apical and middle root canal thirds ranged between 31 and 89 μm. Mean unprepared surfaces were 25.8% ± 12.4%, 22.1% ± 12.0%, and 25.2% ± 11.3% in MB, DB, and P canals, respectively (P > .05) when assessed at high resolution.
By using SAF instruments in vitro, canals in maxillary molars were homogenously and circumferentially prepared with little canal transportation.
本研究旨在描述一种新型镍钛器械——自调式锉（SAF）在上颌磨牙根管成形中的性能。
使用微计算机断层扫描以 20μm 的分辨率对 20 颗上颌磨牙进行扫描。使用 SAF 对根管进行成形，在提供内外振动运动的手机中连续冲洗进行操作。与术前值相比，比较了根管容积、表面积和横截面几何形状的变化。还确定了根管偏移和未预备根管表面积的分数。数据呈正态分布，采用方差分析进行比较。
术前，MB、DB 和 P 根管的平均根管容积分别为 2.88±1.32、1.50±0.99 和 4.30±1.89μm3[校正]；这些值与使用相同方案的早期研究统计学上相似。MB、DB 和 P 根管的容积和表面积均显著增加；根尖和中根管三分之一的平均根管偏移评分在 31 至 89μm 之间。在高分辨率下评估时，MB、DB 和 P 根管的未预备表面分别为 25.8%±12.4%、22.1%±12.0%和 25.2%±11.3%（P>.05）。
在上颌磨牙中使用 SAF 器械进行体外根管预备，根管呈均匀的环形预备，根管偏移较小。
