al-Omari M A, Dummer P M, Newcombe R G
University of Wales College of Medicine.
Int Endod J. 1992 Mar;25(2):57-66. doi: 10.1111/j.1365-2591.1992.tb00738.x.
A total of 300 simulated root canals of various angles and positions of curvature in clear resin blocks were prepared by hand using either K-files, K-Flex files, Flexofiles, Flex-R files, Hedstrom files or Unifiles. Each file type was used to prepare 50 canals employing a linear filing motion and an anticurvature stepback technique. Part 1 of this two-part report describes the efficacy of the files in terms of preparation time, instrument failure, loss of canal length and weight loss from the blocks. Two-way analysis of variance confirmed that there was significant variation for each parameter between instruments, between canal types, and with interaction between instruments and canal types. Overall, preparation with Hedstrom files was significantly quicker than with any other file, whilst preparation with K-files and K-Flex files took significantly longer. Fracture and deformation of instruments occurred substantially less often with Flex-R and Hedstrom files, but significantly more often with Unifiles. Loss of working distance occurred with all file types, but was significantly greater in canals prepared with K-files. Unifiles and Hedstrom files were responsible for significantly more weight loss than the other files, whilst K-files produced significantly less weight loss. Canals with rough undulating walls were created most often by Hedstrom files and Unifiles. Overall, under the conditions of this study, Flexofiles, Flex-R files and Hedstrom files appeared to be substantially more effective than K-files, K-Flex files and Unifiles.
使用K锉、K-Flex锉、Flexofile锉、Flex-R锉、Hedstrom锉或Unifile锉手工制备了300个位于透明树脂块中不同角度和弯曲位置的模拟根管。每种锉类型用于制备50个根管，采用直线锉削运动和抗弯曲逐步后退技术。这份两部分报告的第一部分从制备时间、器械折断、根管长度丧失以及树脂块重量损失方面描述了这些锉的效能。双向方差分析证实，在器械之间、根管类型之间以及器械与根管类型之间的相互作用方面，每个参数都存在显著差异。总体而言，使用Hedstrom锉进行制备显著快于使用任何其他锉，而使用K锉和K-Flex锉进行制备则花费显著更长时间。Flex-R锉和Hedstrom锉导致器械折断和变形的情况显著少于其他锉，而Unifile锉导致的情况显著更多。所有锉类型都会导致工作长度丧失，但使用K锉制备的根管中工作长度丧失显著更多。Unifile锉和Hedstrom锉导致的重量损失显著多于其他锉，而K锉导致的重量损失显著更少。Hedstrom锉和Unifile锉最常造成管壁粗糙起伏不平的根管。总体而言，在本研究条件下，Flexofile锉、Flex-R锉和Hedstrom锉似乎比K锉、K-Flex锉和Unifile锉有效得多。
