Walmsley A D, Murgel C, Krell K V
Department of Endodontics, University of Iowa College of Dentistry.
Endod Dent Traumatol. 1991 Apr;7(2):84-9. doi: 10.1111/j.1600-9657.1991.tb00190.x.
It has been recognised that ultrasonic files leave a diagonal pattern within the canal following endosonic instrumentation. There is confusion on the causative factor on the production of these marks. Furthermore there is little information about the marks produced by sonic files. An in vitro system consisting of highly polished dentin discs demonstrated that the ultrasonic K-file made a diagonal pattern that was an imprint of the cutting edges of the file. The sonic files produced different markings which were the result of their longitudinal and transverse motion. Root canals of extracted teeth were prepared with these instruments and similar grooves were observed. The ultrasonic K-file had diagonal grooves in the coronal and middle third of the root canal but longitudinal marks in the apical third. The rispisonic and shaper files produced debris even in the presence of NaOCl. This debris was formed into discrete parallel bands. Both longitudinal and transverse grooves were present and the canal had many other scratches similar to those seen with the dentin discs. There were differences between the marks produced by either ultrasonic or sonic endosonic instruments but it is unknown whether this influences the long term prognosis of the root canal therapy.
人们已经认识到，在超声器械预备根管后，超声锉会在根管内留下斜行痕迹。对于这些痕迹产生的原因存在混淆。此外，关于声波锉产生的痕迹的信息很少。一个由高度抛光的牙本质盘组成的体外系统表明，超声K锉形成的斜行痕迹是锉刃的印记。声波锉产生了不同的痕迹，这是它们纵向和横向运动的结果。用这些器械对拔除牙齿的根管进行预备，观察到了类似的凹槽。超声K锉在根管的冠部和中部三分之一处有斜行凹槽，但在根尖三分之一处有纵向痕迹。即使在有次氯酸钠存在的情况下，Rispisonic锉和成型锉也会产生碎屑。这些碎屑形成了离散的平行带。纵向和横向凹槽都存在，并且根管还有许多其他类似于牙本质盘上所见的划痕。超声或声波超声器械产生的痕迹之间存在差异，但尚不清楚这是否会影响根管治疗的长期预后。
