ReDent-Nova Inc, Ra'anana, Israel.
J Endod. 2010 Apr;36(4):691-6. doi: 10.1016/j.joen.2009.12.028.
The study was designed to explore the mechanical properties of the self-adjusting file (SAF) and its application in the root canal using continuous irrigation.
The compressibility of the SAF file and the resulting peripheral force were measured using specially designed systems. The abrasivity of the file was tested on dentin blocks representing a flat root canal. The durability of the SAF file was tested using a functional fatigue-to-failure assay. Degradation of the file was evaluated by using files that were previously used for 10, 20, and 30 minutes and comparing their efficacy with that of new, unused files. The potential of extruding irrigant beyond the apex was explored in roots with an open apical foramen.
The SAF file was elastically compressible from a diameter of 1.5 mm to dimensions similar to those of a #20 stainless steel K-file. This compression resulted in an evenly applied force to the root canal walls. The in-and-out vibration of the file and the peripheral force, combined with its abrasivity, allow for hard-tissue removal. Under the conditions of the experiment, no mechanical failure was observed with up to 29 minutes of operation in the root canal. The file loses its efficacy after prolonged use, with a 40% reduction after 30 minutes of operation. The operation of the file with continuous irrigation did not push the irrigant beyond an open apical foramen.
The SAF file is an elastically compressible file that effectively removes dentin and can mechanically endure use under its recommended mode of operation with a minimal loss of efficacy.
本研究旨在探讨自调整锉（SAF）的力学性能及其在连续冲洗条件下在根管中的应用。
使用专门设计的系统测量 SAF 锉的压缩性及其产生的外周力。在代表平根管的牙本质块上测试锉的研磨性。使用功能疲劳失效试验测试 SAF 锉的耐用性。通过使用先前使用过 10、20 和 30 分钟的锉来评估锉的降解情况，并将其效果与新的未使用锉进行比较。在根尖孔开放的根管中探索将冲洗剂挤出根尖以外的可能性。
SAF 锉可从直径 1.5mm 弹性压缩至与 #20 不锈钢 K 锉相似的尺寸，这一压缩会导致向根管壁均匀施加力。锉的进出振动和外周力，再加上其研磨性，允许去除硬组织。在实验条件下，在根管内操作长达 29 分钟也未观察到机械故障。锉经过长时间使用后会失去功效，使用 30 分钟后效率降低 40%。在连续冲洗条件下操作锉不会将冲洗剂推至开放的根尖孔以外。
SAF 锉是一种可弹性压缩的锉，可有效去除牙本质，并可在其推荐的操作模式下机械耐受使用，其功效仅会有轻微损失。
