Department of Endodontology, Academic Centre of Dentistry Amsterdam, University of Amsterdam and VU University, Amsterdam, The Netherlands.
J Endod. 2012 Jul;38(7):1004-6. doi: 10.1016/j.joen.2012.03.003. Epub 2012 Apr 26.
The aim of this study was to compare the percentage of the residual gutta-percha-occupied area (PRGPA) in root canals after retreatment using ProTaper retreatment files (Dentsply Maillefer, Ballaigues, Switzerland) with or without the additional use of Self-Adjusting Files (SAFs; ReDent-Nova, Ra'anana, Israel).
Root canals in 33 curved mesiobuccal roots of the first maxillary molars were cleaned and filled with gutta-percha and AH26 sealer (Dentsply De Trey, Johnson City, TN). Retreatment instrumentation was performed in 28 roots with ProTaper retreatment files and Hedström files. The Additional use of SAF was performed in 14 of the 28 roots. Five roots were not retreated. All roots were sectioned horizontally at 2, 4, and 6 mm from the apex. PRGPA was measured at each section. Scores 1 through 5 were used to represent the increasing extent of PRGPA; score 1 was 0%, and score 5 was >30%. The data were analyzed with nonparametric tests.
Score 5 was recorded in all sections from roots that were not retreated. In retreated roots, the scores for the group using SAF were significantly lower than that without using SAF (P = .045); however, scores were higher at 2 mm than at other levels of the root regardless of whether the SAF had been used (P = .03).
The complete removal of gutta-percha from the apical portion of curved canals remains a challenge. The additional use of SAF removed more gutta-percha than ProTaper alone.
本研究旨在比较使用 Protaper 再治疗锉（登士柏麦尔公司，瑞士）和/或附加使用自调整锉（ReDent-Nova，拉纳纳，以色列）进行再治疗后根管内剩余牙胶占据区（PRGPA）的百分比。
清洁并填充 33 颗上颌第一磨牙近中颊根的根管，用牙胶和 AH26 密封剂（登士柏德特里，约翰逊市，田纳西州）。在 28 根根管中使用 Protaper 再治疗锉和 Hedström 锉进行再治疗仪器操作。在其中的 14 根根管中附加使用了 SAF。5 根根管未进行再治疗。所有根管在距根尖 2、4 和 6mm 处水平切片。在每个切片处测量 PRGPA。分数 1 至 5 用于表示 PRGPA 增加的程度；分数 1 为 0%，分数 5 为>30%。使用非参数检验对数据进行分析。
未进行再治疗的所有根管的所有切片中均记录为分数 5。在进行再治疗的根管中，使用 SAF 的组的分数明显低于未使用 SAF 的组（P =.045）；然而，无论是否使用 SAF，在根尖 2mm 处的分数均高于其他水平（P =.03）。
从弯曲根管的根尖部分完全清除牙胶仍然是一个挑战。附加使用 SAF 比单独使用 Protaper 去除更多的牙胶。
