- 作者：Jin-Woon Kim ; DDS ; MS ; PhD&lowast ; ; Jung-Hong Ha ; DDS ; MS ; PhD&dagger ; ; Gary Shun-Pan Cheung ; BDS ; MDS ; MSc ; PhD&Dagger ; ; Antheunis Versluis ; PhD§ ; ; Sang-Won Kwak ; DDS ; MS&lowast ; ; Hyeon-Cheol Kim ; DDS ; MS ; PhD&lowast ; ; golddent@pusan.ac.kr" class="auth_mail" title="E-mail the corresponding author
- 关键词：Distortion ; Reciproc ; reciprocating nickel-titanium file ; torsional resistance ; WaveOne
- 刊名：Journal of Endodontics
- 出版年：2014
- 出版时间：October 2014
- 年：2014
- 卷：40
- 期：10
- 页码：1671-1675
- 全文大小：1042 K
Methods
With the file tip secured at various levels (3, 4, or 5 mm) of Reciproc R25 and WaveOne Primary, the distortion angles and torsional loads were monitored during counterclockwise movement at 2 rpm until fracture (n = 10 at each level) for a load-distortion graph. The rotation angles and loads at the beginning point of the plateau, the ultimate torsional strength, final fracture angle, and toughness were determined. The data were analyzed using 1-way analysis of variance and the Tukey post hoc test at α = .05. The lateral longitudinal aspect and the fracture cross-section of each specimen were examined by scanning electron microscopy after the test.
Results
The rotation angle at the beginning point of the plateau was significantly greater for a binding site farther away from the tip of the instrument for both systems (P < .05), and all were greater than 170° (preset in the dedicated motor from manufacturer). The ultimate strength and toughness also increased significantly at levels farther away from the instrument tip (P < .05). All specimens showed typical topographic features of torsional fracture, including the circular abrasion marks and fibrous dimples near the rotation center after the test.
Conclusions
It was determined that the 2 brands of reciprocating files are safe when operated at the rotational angle in the proprietary motor.