@Article{, title={Evaluation of different techniques used in non surgical endodontic retreatment for teeth with different obturation techniques (An in-vitro study)}, author={Nsar Muhyaddin Aziz نصر محي الدين عزيز and Dara Hamarashed Saeed دارا سعيد}, journal={Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد}, volume={24}, number={special issue 1}, pages={31-35}, year={2012}, abstract={Background: Retreatment procedures in endodontic practice require complete removal of the original root fillingmaterials. The aim of this study was to evaluate the efficacy & time required for rotary Nickel titanium NiTi instruments(Pro-Taper) with and without solvent in the removal of obturation materials during root canal retreatment incomparison with hand instruments using Hedstrom files with solvent in relation to different obturation techniques.Materials and method: Ninety extracted human roots were instrumented by ProTaper rotary files to (F3) ISO # 30 andthe samples were randomly divided into three groups of 30 roots for each group A: obturated by cold lateralcondensation technique, group B: obturated by Injectable thermoplasticized technique, group C: obturated bycarrier based gutta-percha technique (Soft Core) obturator. Each main group of roots was randomly subdivided intothree subgroups, 10 roots each. Removal of gutta-percha was performed the following techniques; (1) Pro-Taperwithout solvent, (2) Pro-Taper with solvent and (3) Hedstrom files with solvent. The roots were split longitudinally. Thearea of remaining filling was evaluated by using stereomicroscope at three levels in the canal and time ofretreatment was determined in each group.Results: One-way ANOVA test indicated that the rotary NiTi instruments Pro-Taper with and without solvent leftsignificantly less remaining filling materials (P < 0.001) compared to Hedstrom files with solvent while there was nosignificant difference at (p<0.05), between Pro-Taper with solvent and without solvent. In groups obturated by coldlateral condensation and injectable thermoplasticized techniques left significantly less remaining filling materials at(p<0.05), than group obturated by soft core obturators. The retreatment time was significantly less at (P < 0.001)when the rotary NiTi Pro-Taper instrument was used compared to hand.Conclusion: ProTaper rotary instrument with and without solvent was found to be effective and faster than handinstruments and Cold lateral condensation technique and inject able thermo plasticized technique better removedin retreatment than Soft Core obturator technique

} }