Basic ResearchRemoval of Filling Materials from Oval-shaped Canals Using Laser Irradiation: A Micro–computed Tomographic Study
Section snippets
Sample Selection
After ethics committee approval (protocol #116/2013), 110 straight single-rooted extracted mandibular canines were initially selected on the basis of radiographs (Belmont Phot-X II; Takara Belmont Corp, Osaka, Japan) taken in both buccolingual and mesiodistal directions to detect any possible root canal obstruction. All teeth presenting apical curvature, previous endodontic treatment, resorptive defects, or more than 1 root canal were excluded. The specimens were disinfected in 0.1% thymol
Results
Table 1 summarizes the means and standard deviations of the percentage remaining filling materials of the experimental groups after the use of rotary instruments as well as additional laser irradiation. Overall, none of the retreatment procedures completely removed the filling materials from the root canals.
After using rotary instruments, the mean percentage volume of the filling residue ranged from 13%–16%, with no statistical significant difference between groups (P > .05). Despite
Discussion
Controversial results regarding the efficacy of rotary instruments on the root canal retreatment procedures can be found in the literature 6, 10 and may be explained by methodological differences among the studies such as sample selection, evaluation methods, experimental design (ie, number of files, time of the procedure, speed and torque of the motor, taper and size of instruments, and amount of irrigants), and the additional use of heat or solvents. Regarding the latter, no solvent was
Conclusions
Under the limitations of this ex vivo study, neither retreatment protocols were able to render root canals free of root filling remnants. The additional use of lasers improved the removal of filling materials after canal retreatment with rotary instruments.
Acknowledgment
Supported by the Scientific and Technological Research Council of Turkey–TUBİTAK (grant no. 114S052).
The authors deny any conflicts of interest related to this study.
References (30)
- et al.
Three-dimensional evaluation of effectiveness of hand and rotary instrumentation for retreatment of canals filled with different materials
J Endod
(2008) - et al.
Outcomes of nonsurgical retreatment and endodontic surgery: a systematic review
J Endod
(2009) - et al.
Endodontic retreatment—case selection and technique. 3. Retreatment techniques
J Endod
(1990) - et al.
The effectiveness of manual and mechanical instrumentation for the retreatment of three different root canal filling materials
J Endod
(2008) - et al.
Treatment outcome in endodontics: the Toronto study—phases 3 and 4: orthograde retreatment
J Endod
(2008) - et al.
Self-adjusting files in retreatment: a high-resolution micro-computed tomography study
J Endod
(2012) - et al.
Removal of gutta-percha from root canals using the self-adjusting file
J Endod
(2012) Nonsurgical retreatment
J Endod
(2004)- et al.
Effects of the Nd:YAP laser on coronal restorative materials: implications for endodontic retreatment
J Endod
(2000) - et al.
In vitro study of a Nd:YAP laser in endodontic retreatment
J Endod
(1998)