Effect of fentanyl on the success of inferior alveolar nerve block for teeth with symptomatic irreversible pulpitis: a randomized clinical trial

Aim: The purpose of this prospective, randomized, double-blind study was to evaluate the effect of adding fentanyl to lidocaine 2% with epinephrine 1:80,000 on the success of the inferior alveolar nerve block in mandibular molar teeth with symptomatic irreversible pulpitis. Methodology: 100 healthy adult patients with diagnosis of symptomatic irreversible pulpitis in one of the mandibular molar tooth were selected and randomly divided in two groups of 50 patients each. In the first group (fentanyl group), 0.25 ml of a cartridge of 1.8 ml of 2% lidocaine with 1:80,000 epinephrine solution was drained and the same amount from 50μg/ ml fentanyl solution was added to the cartridge. In the second group (non-fentanyl group) 0.25 ml of a cartridge of 1.8 ml of 2% lidocaine with 1:80,000 epinephrine solution was drained and the same amount from saline solution was added to the cartridge. Each group received two cartridges of prepared soloution with inferior alveolar nerve block injection technique. Access cavity preparation started 15 minautes after injection and after confirming the lip numbness. Success defined as no pain or mild pain on the basis of Heft-Parker visual analog scale during access cavity preparation or initial instrumentation. Data were analyzed by T-test and Chi-square Results: The success rate of inferior alveolar nerve block injection was 58% for Fentanyl group and 46% for Non-Fentanyl group. There was no significant difference between the two groups (P=0.23). Conclusions: The addition of fentanyl to lidocaine 2% with epinephrine 1:80,000 did not increase the success rate of the inferior alveolar nerve block in mandibular molar teeth with symptomatic irreversible pulpitis

Evaluation of coronal microleakage of mineral trioxide aggregate plug-in teeth with short roots prepared for post placement using bacterial penetration technique

Context: Two of the problems of the placement of posts in teeth with short roots are to determine the minimum length of the canal obturation material at the apical third of the root canal and removal of all the canal obturation material from the root canal during post space preparation. Aim: The aim of the present study was to compare the coronal microleakage of mineral trioxide aggregate (MTA) plug and gutta-percha in short roots prepared for post placement using the bacterial penetration technique. Materials and Methods: In the presentin vitro study, 40 extracted single-rooted anterior teeth measuring 13 mm in root length were selected. Since the roots were short, 3 mm of the root length was allocated to the root canal obturation material and 10 mm of the root length was allocated to post placement. After preparation of the root canals, post spaces were prepared and the samples were randomly divided into two groups of gutta-percha and MTA. Fifteen root canals were obturated with gutta-percha and the post space was immediately prepared, with 3 mm of gutta-percha remaining in the apical end of the root canal. In 15 teeth, MTA plugs were placed, which measured 3 mm in length. The samples were placed in the Enterococcus faecalis bacterial microleakage system for 120 days. The time for the turbidity of each sample was recorded. Data were analyzed with Fisher's exact test. Results: During the study period, turbidity was observed in all the gutta-percha samples and in only four MTA samples, with statistically significant differences between the two groups (P< 0.001). Conclusion: Based on the results, MTA exhibited much better sealing ability compared to gutta-percha as a root canal obturation material in teeth with short roots

Comparative evaluation of the effectiveness of different rotary systems in removal of root canal filling materials

Aim: The aim of this study was to compare the remaining root canal filling materials after instrumentation using ProTaper Universal Retreatment (PTUR) system alone or combined with Neoniti, One Curve, and using hand Hedstrom files and Gates Glidden drills using cone beam computed tomography (CBCT) images. Methodology: Fifty-two mandibular premolars with single and straight canals were used. The canals were instrumented with ProTaper rotary instruments up to F3 and filled with gutta-percha and AH26 sealer. All the samples were placed into silicone models. Samples were scanned with CBCT and assigned into four groups (n=13): the PTUR system group, the PTUR system plus Neoniti group, the PTUR system plus One Curve group, and the hand Hedstrom files plus Gates Glidden group. The specimens were scanned once again after retreatment procedures, and the volume of the remaining filling materials was determined. Data were analyzed using Kruskal-Wallis and Dunn tests (α=0.05). Results: None of the retreatment procedures provided complete removal of the filling materials. Hedstrom files plus Gates Glidden removed more residual obturation materials than the other groups. The additional use of the Neoniti or One Curve systems significantly improved the removal of filling materials when compared with the PTUR system alone (P&lt;0.05). The differences between the PTUR plus Neoniti group and the PTUR plus One Curve group were not statistically significant (P&gt;0.05). Conclusions: Using Gates Glidden and Hedstrom files was the most effective way for retrieval of endodontic material from the root canals, while PTUR alone was the least effective method. Re-instrumenting with rotary files significantly improved the removal of root filling materials