Peters Ove A, Arias Ana, Paqué Frank
Department of Endodontics, Arthur A. Dugoni School of Dentistry, University of the Pacific, San Francisco, California.
Department of Endodontics, Arthur A. Dugoni School of Dentistry, University of the Pacific, San Francisco, California.
J Endod. 2015 Sep;41(9):1545-50. doi: 10.1016/j.joen.2015.06.007. Epub 2015 Aug 1.
A novel S-shaped rotary file was developed to conform to nonround canal cross sections. However, the instrument should also perform well in small curved canals. This study used micro-computed tomographic scans to test the effects of TRUShape (Dentsply Tulsa Dental Specialties, Tulsa, OK) and a conventional rotary on canal geometry.
Twenty mandibular molars with independent mesial canals were submitted to preoperative micro-computed tomographic scans (20-μm resolution). Canals were randomly allocated to 2 groups using Vortex (Dentsply Tulsa Dental Specialties) and TRUShape for shaping according to the directions for use. Scans were obtained after size 20/.06 and 30/.06; the following outcome variables were calculated: dentin volume, smallest radicular wall thickness, treated canal surface, canal transportation, and accumulated hard tissue debris. The number of preparation errors was tabulated; data were statistically contrasted using repeated measures and factorial analyses of variance.
The initial canal sizes were similar in both groups. Both instruments promoted preparation with no overt procedural errors. Vortex removed significantly more dentin both at size #20 and #30 (P < .02). Significantly (P < .02) more radicular wall dentin remained toward the furcation in the TRUShape group (1.02 ± 0.25 mm vs 0.94 ± 0.22 mm). The untreated surface at size #20 was 28.5 ± 13.9 and 19.4 ± 8.9 (P < .05), and it was 15.1 ± 8.5 and 11.3 ± 4.9 (P > .05) at size #30 for TRUShape and Vortex, respectively. Canal transportation at size #30 varied between 85 ± 57 μm and 179 ± 65 μm; the overall transportation scores were significantly lower for TRUShape (P < .05).
TRUShape provided conservation of dentin by limiting dentin removal and in the absence of substantial canal transportation. In the present study, the use of TRUShape in the mesial canals of mandibular molars did not result in decreased amounts of unprepared canal surface.
研发了一种新型S形旋转锉以适应非圆形根管横截面。然而，该器械在小弯曲根管中也应表现良好。本研究使用显微计算机断层扫描来测试TRUShape（登士柏 Tulsa 牙科专业公司，塔尔萨，俄克拉荷马州）和传统旋转器械对根管形态的影响。
选取20颗具有独立近中根管的下颌磨牙进行术前显微计算机断层扫描（分辨率为20μm）。根据使用说明，使用Vortex（登士柏 Tulsa 牙科专业公司）和TRUShape将根管随机分为两组进行预备。在使用20/.06和30/.06号器械后进行扫描；计算以下结果变量：牙本质体积、最小根尖壁厚度、处理后的根管表面积、根管偏移以及累积的硬组织碎屑。记录预备错误的数量；使用重复测量和析因方差分析对数据进行统计学对比。
两组的初始根管尺寸相似。两种器械均能顺利完成预备，未出现明显的操作失误。在20号和30号器械预备时，Vortex去除的牙本质明显更多（P <.02）。TRUShape组中，朝向根分叉处保留的根尖壁牙本质明显更多（P <.02）（1.02 ± 0.25 mm对0.94 ± 0.22 mm）。20号器械预备后，TRUShape组和Vortex组未处理的根管表面积分别为28.5 ± 13.9和19.4 ± 8.9（P <.05）；30号器械预备后，分别为15.1 ± 8.5和11.3 ± 4.9（P >.05）。30号器械预备后的根管偏移在85 ± 57μm至之间179 ± 65μm；TRUShape组的总体偏移分数明显更低（P <.05）。
TRUShape通过限制牙本质去除量且在无明显根管偏移的情况下实现了牙本质的保存。在本研究中，在下颌磨牙近中根管中使用TRUShape并未导致未预备的根管表面积减少。
