Thesis Type: Doctorate
Institution Of The Thesis: Gazi Üniversitesi, Sağlık Bilimleri Enstitüsü, Turkey
Approval Date: 2015
Student: ÖZLEM ŞENGEZER
Supervisor: ÖZGÜR UZUNAbstract:
Aim: The aim of this study was to evaluate the efficiency of two techniques and instrument systems which claims to remove the root filling material from the root canal faster and more effective, on the roots which obturated with gutta-percha and three different root canal sealers. Materials and Methods: In this study, 110 human mandibular extracted canine teeth were used. The teeth were divided into two main groups. Group 1 was prepared using Reciproc R 40 instrument, filled with R40 Reciproc gutta-percha cone with AH26 (n = 15), EndoREZ (n = 15) and I Rootsp (n = 15) sealers. R25 instrument of the same system, was used to remove root canal fillings and R50 instrument was used for repreperation (n = 45) of samples. Group 2 was prepared using PTU F3 instrument and filled with PTU F3 gutta-percha cone with AH26 (n = 15), EndoREZ (n = 15) and I RootSp (n = 15) sealers. Retreatment instruments of the same system (PTR), were used for removing the root canal fillings and F4 instrument was used for repreparation (n = 45)of samples. 20 samples were left as a control group just prepared and without root filling. The samples were evaluated with radiographic technique, photographic technique and SEM. Time analysis was also used to identify the required time for retreatment proceduresof each sample. Wilkins Shapiro test was used to test the distribution of data. Kruskal-Wallis test was used to detect the statistically significant differences. Mann-Whitney U test was used for pair wise comparisons. The level of significance was taken as p≤0.05. Bonferroni corrections were made for multiple comparisons. Statistical analyses could not be used for SEM evaluations. Results: Reciproc system was removed root canal fillings faster than PTR system in all samples (P=0.000). More residual material was assessed in coronal and apical sections of all samples when samples were evaluated with radiographic technique(P>0.05). When samples were evaluated with Photographic technique, more residual material was assessed in apical sections of samples(P>0.05). More residual material was assessed in apical section when samples were evaluated with SEM. Conclusion: In the limits of the present study, Reciproc and Protaper Retreatment systems have similar effects on removing of the root canal filling materials. Both of the two systems could not remove the filling materials from root canals completely.