فهرست مطالب e. esnaashari

Achieving adequate pulpal anesthesia could be challenging in mandibular molars. There are some disagreements about the success rate of local infiltration anesthesia with articaine as primary injection. Therefore, the aim of this study was to assess the efficacy of 4% articaine lingual subperiosteal injection as the primary injection for permanent mandibular second molars in comparison with inferior alveolar nerve block (IANB).  

Fifteen healthy adult volunteers participated in this study. A randomized, split-mouth, single-blind design was used to allocate each side of the mandible in each patient to the test or control group. On the test side, lingual subperiosteal injection with 4% articaine and 1:100,000 epinephrine wasperformed for the mandibular second molar; whereas, in the control group, an IANB with 2% lidocaine and 1:80,000 epinephrine was administered. Electric pulp testing was done at baseline, and also at 5, 8, 11, 15, 20, 25, 30, 45, 60, 75, and 90 minutes after injection. Statistical analysis was carried out using t-test and Chi-square test.

The success rate of IANB was significantly higher than that of lingual subperiosteal injection (P=0.0001). The difference in the onset of action between the two groups was significant (P<0.05). Anesthesia duration was 61.0±28.0 minutes in IANB group and 10.2±12.4 minutes in lingual subperiosteal injection group, with a significant difference between them (P<0.01).

IANB with 2% lidocaine is preferable to 4% articaine lingual subperiosteal injection due to its superior success rate, faster onset of action, and longer duration of effect.

Complete removal of gutta-percha from the root canal system and its remnants is a challenge in endodontic retreatment. This ex-vivo study aimed to assess the efficacy of XP-Endo Finisher R (XEFR) in removing root filling remnants from straight canals of mandibular premolars in root canal retreatment.  

In this ex-vivo study, 30 single-rooted mandibular premolars with straight roots were selected. The root canals were instrumented and filled. Retreatment was then performed using D RaCe system. Teeth were then randomized into two groups of A and B (n=15). In group A, root canal retreatment was completed with XEFR. In group B, XEFR was not used. To evaluate the filling material remnants, the roots were split into halves and assessed under a stereomicroscope and photographed. The amount of remaining gutta-percha in the coronal, middle and apical thirds of the roots was measured by AUTOCAD software and analyzed with two-way ANOVA.

The amount of residual filling material was significantly lower in the coronal, middle and apical thirds and the entire root length in XEFR group (P<0.001).

 Use of XEFR significantly decreased the residual root filling material in the root canals.

This study aimed to compare the cytotoxicity of AH Plus and DC Canal SE sealer after final setting.

In this in vitro, experimental study, human gingival fibroblasts (HGFs) were cultured in Dulbecco’s modified Eagle’s medium supplemented with 10% fetal bovine serum, 100 U/mL penicillin, and 100 µg/mL streptomycin, and incubated at 37°C and 5% CO2. Cells at a density of 5000 cells/well were seeded in a 96-well plate for the methyl thiazolyl tetrazolium (MTT) assay. The cells were incubated with AH Plus and DC Canal SE sealers. Specimens of freshly mixed sealers were fabricated with 4 mm height and 10 mm diameter, and  incubated at 37°C for 24 hours for setting. Each specimen was incubated with 10 mL of diluted culture medium at 37°C and 5% CO2 for 24 hours. Finally, the solution was filtered using a 0.22-µm filter. Different dilutions (1, 1/2, 1/4, 1/8) were prepared, and cell viability was assessed at 24 and 72 hours by measuring the optical density of the solutions spectrophotometrically. Data were analyzed by ANOVA and Tukey’s test.

Cell viability in presence of all concentrations of AH Plus and DC Canal SE was significantly lower at 72 hours compared with 24 hours (P<0.001). Cell viability in presence of AH Plus was significantly higher compared with DC Canal SE at all concentrations and time points.

Cell viability was higher in presence of AH Plus compared with DC Canal SE sealer in all concentrations and time points.