University of Tlaxcala, Tlaxcala, Mexico.
J Endod. 2011 Sep;37(9):1276-8. doi: 10.1016/j.joen.2011.05.042. Epub 2011 Jul 16.
The complex anatomy of the root canal system has been shown to limit the penetration of irrigating solutions into the apical third; hence, the aim of this study was to determine whether the use of a patency file is related to the presence of a radiopaque irrigating solution in the apical third of human root canals after using passive ultrasonic activation in vivo.
Forty human root canals were randomly divided into two groups. Apical patency was maintained in one group (n = 21) during shaping and cleaning procedures with a no. 10 K-file 1 mm beyond the working length (WL) but not in the other group (n = 19). In both groups, the canals were shaped with the Pro Taper system (Dentsply-Maillefer, Ballaigues, Switzerland). Irrigation was performed with 1 mL of a solution prepared with a radiopaque contrast medium and sodium hypochlorite 5.25%, and then passive ultrasonic irrigation (PUI) was applied after the shaping procedure. Digital images were taken, and a calibrated reader determined the presence or absence of the irrigating solution in the apical third.
There were significantly more canals with irrigant in the apical third after PUI when apical patency was maintained with a no. 10 file 1 mm beyond the WL than when apical patency was not maintained throughout the cleaning and shaping procedures (P = .02).
Maintaining apical patency and then using PUI improves the delivery of irrigants into the apical third of human root canals.
根管系统的复杂解剖结构被证明限制了冲洗液进入根尖三分之一的渗透；因此，本研究旨在确定在体内使用被动超声激活后，使用通条是否与根尖三分之一存在不透射线的冲洗液有关。
将 40 个人类根管随机分为两组。一组（n = 21）在塑形和清洁过程中用 10 号 K 锉保持根尖通畅，超出工作长度（WL）1 毫米，但另一组（n = 19）则不保持。两组均采用 ProTaper 系统（Dentsply-Maillefer，Ballaigues，瑞士）进行塑形。用含有不透射线对比剂和次氯酸钠 5.25%的溶液进行冲洗，然后在塑形程序后应用被动超声冲洗（PUI）。拍摄数字图像，由经过校准的读数器确定根尖三分之一处是否存在冲洗液。
当用 10 号锉超出 WL 1 毫米保持根尖通畅时，PUI 后根尖三分之一处有冲洗液的根管明显多于整个清洁和塑形过程中不保持根尖通畅的根管（P =.02）。
保持根尖通畅，然后使用 PUI 可改善根尖三分之一处人类根管内冲洗液的输送。
