Evaluation of Gutta Percha removal from different niti rotary file system: An in vitro study

Abstract

The main goal of endodontic retreatment is cleaning and shaping of the root canal with removal of old root filling material. Hand instruments and rotary instruments are mainly used for removing this filling material; as hand instruments are time consuming and tedious so we used rotary instrumentation for removal of gutta percha. The main aim of this study is to compare the relative efficacy of three different NI TI rotary instrumentation systems for removal of gutta-percha from root canal during endodontic retreatment. Materials and Methods: Sixty freshly extracted, single-rooted human anterior teeth were instrumented with K-files, and each root canal was filled with gutta-percha and AH Plus (Dentsply Detrey, Konstanz, Germany) sealer using lateral compaction. Specimens were then divided into three experimental groups with ten specimens each. The removal of gutta-percha was performed using Pro-Taper retreatment files, Mtwo retreatment files, and Edge file XR. The amount of root canal filling material remnant in the coronal, middle and apical thirds was measured using stereomicroscope. Result: The data was evaluated statistically using analysis of variance. Pro-Taper group was found to have less remnant filling material as compared to the other groups in coronal and middle thirds, but a significant difference was observed between edge file XR and Mtwo. Conclusions: It was concluded that EDGE FILE XR, rotary retreatment system proved to be the most efficient method of removing gutta-percha and sealer in comparison to the other two retreatment files and M-TWO retreatment files required less time to remove root filling material than the other instruments.

Comparative Evaluation of the Incidence of Dentin Microcracks Following Biomechanical Preparation Using Four Different Nickel-Titanium Rotary File Systems: An In Vitro Study

“…A study conducted by Adorno et al [ 11 ] reported the incidence of apical microcracks in 50% of mandibular premolars after canal preparation to the apical foramen, which is in accordance with the present study. The occurrence of stress due to successive instrumentation, the low capability of the thin and fragile dentin in the apical area to withstand the mechanical stress produced by direct contact with the instrument tip, and features of the files, such as taper angle, flexibility, and cross-section, may also influence the formation of cracks [ 21 ].…”