Aim: To assess and compare the cyclic fatigue resistance of EdgeFile X7, EdgeOne, WaveOne Gold and WaveOne rotary files using artificial canals with different angles and radii of curvature. Materials and methods:One hundred and sixty NiTi files from four different systems (N= 40 each) were used; Group 1: WaveOne, Group 2: WaveOne Gold, Group 3: EdgeOne and Group 4: EdgeFile X7. The files were tested for cyclic fatigue resistance using a custom made static model with various angles and radii of curvature (angle 60° radius 2.5mm and radius 5mm and angle 90° radius 2.5mm and radius 5mm). The files were operated according to the manufacturers' instructions inside the artificial canals till fracture. A digital stopwatch was used to record the time till fracture (TTF) in seconds and the length of the fractured segment (FL) was recorded. Results:The highest TTF values were found in the WaveOne Gold group followed by the EdgeOne group then the WaveOne group while the least was in the EdgeFile X7. There was no statistically significant difference between WaveOne Gold and EdgeOne at all angles and radii of curvature. There was a statistically significant difference between both the WaveOne Gold, EdgeOne and the EdgeFile X7. Angle 90° with 2.5mm radius showed the lowest cyclic fatigue resistance. WaveOne Gold and EdgeFile X7 showed lower FL compared to WaveOne. Conclusion:WaveOne Gold and EdgeOne showed superior comparable cyclic fatigue resistance which was higher than that of WaveOne while EdgeFile X7 showed the least cyclic fatigue resistance.

Postoperative pain management is a challenging problem in the clinical practice of endodontics. It has been postulated that intraligamentary injection enables the application of anti-inflammatory agents directly in the periapical region.Aim: Assess and compare the efficacy of local intraligamentary injection of dexamethasone and piroxicam on postoperative pain in mandibular molars with symptomatic irreversible pulpitis.Subjects and Methods: Forty-two patients were included and randomly assigned to three equal groups (n=14). After administration of standard inferior alveolar nerve block, each participant received intraligamentary injection of 0.4 ml of either 8 mg/2 ml dexamethasone, 20 mg/ml piroxicam or 2% mepivacaine. Standard endodontic treatment was performed in a single visit. The pain was assessed by means of the Numerical Rating Scale preoperatively and postoperatively after 4, 6, 12, 24 and 48 hours. All demographic, baseline and outcome data were collected and statistically analyzed.Results: There was no significant difference between the three groups regarding age, gender and preoperative pain. There was a significant reduction in pain in all groups, however, there was a statistically significant reduction in postoperative pain in piroxicam group compared to the mepivacaine group at all time intervals. There was a statistically significant reduction in postoperative pain in the dexamethasone group when compared to the mepivacaine group only at 4, 24 and 48 hours. However, there was no significant difference found at 6 and 12 hours. There was no significant difference between dexamethasone and piroxicam groups.Conclusions: It was concluded that preoperative intraligamentary injection of dexamethasone and piroxicam show a significant success in reducing postoperative pain compared to mepivacaine with no preference regarding using either of them.

No abstract

No abstract