Background: The purpose of this study was to evaluate and compare centering ability and canal transportation of simulated S-shaped canals instrumented with four different types of rotary nickel-titanium systems. Materials and Methods: Forty simulated S-shaped canals in resin blocks were divided into four groups of ten each and were instrumented to an apical size 25 by different instrumentation technique using ProTaper Universal files (group A), ProTaperNext (group B), Reciproc (group C) and WaveOne (group D).Centering ability and canal transportation was measured at (11) measuring points from D0 to D10 bysuperimposion of the pre- and post-operative images obtained by using digital camera in standardized manner. An assessment of the canals shape was determined using Photoshop CS2 and AutoCAD software. The data were analyzed statistically using ANOVA and LSD test. Results: In terms of centering ratio values, there was no statistically significant difference among the four groups at the coronal portion of the canals, with ProTaper system showing the least centering ability at all levels except at apical foramen. At the apical curvature, the Reciproc and WaveOne groups showed better centering ability than ProTaperNext and the difference was statistically highly significant among them at these points, while at the coronal curvature the ProTaperNext showed better centering ability than Reciproc and WaveOne. Canal transportation was seen in all groups but the ProTaper systems showed more transportation values at almost levels when compared with the other groups with the least values by ProTaperNext at the coronal curvature and the least values by Reciproc and WaveOne at the apical curvature. Conclusions: Under the conditions of this study, ProtaperNext ,WaveOne and Reciproc instruments maintained the original curvature significantly better than ProTaperUniversal at almost levels. ProtaperNext showed a better shaping ability than Reciproc and WaveOne at the coronal curved section while at apical curved section Reciproc and WaveOne showed a better shaping ability than ProtaperNext. Key words: centering ability, canal transportation, ProTaperNext, Reciproc, WaveOne.
Gymnastics play from sports games that need to use appropriate methods and strategies that address mental abilities and that let the learner create and think about better performance with the supervision and guidance of the teacher. The researcher has chosen meditative thinking, which is a kind of thinking that needs to be taken care of. It is thinking about the situation in front of the individual, analysing it to his elements and drawing up plans that need to be understood with a view to reaching the results required by the situation and evaluating the results in the light of the plans. The analysis of the situation looks to different elements and look for internal relationships between these elements in this case. The problem is that fem
... Show MoreBackground: Analysis of human reports and comparison with results of experimental animals indicate that the effects of progesterone on human not analogous to experimental animals fetus, many studies showed that exposure to progesterone during developing of genital tract of human fetus was not teratogenic. Other studies which performed on laboratory animals found association between progesterone administration during gestation and genital malformation. Objectives: to explore the effect of progesterone in 10.2 mg/kg intraperitoneal injection in mice on testis development and anogenital distance. Materials and Methods: ten pregnant mice divided into five mouse control group that injected10. 2mg/kg sesame oil and treated group that injected pro
... Show MoreContemporary developments in various sciences and the impact of technological changes require an integrated vision of the activities and work of the organization in Iraq in light of the high costs of products and their low quality compared to imported products of high quality and low cost, and the need to use modern cost techniques based on a clear and specific philosophy that contributes to increasing the efficiency and effectiveness of management In the business environment and how it can contribute to reducing product costs and being environmentally friendly at the same time, it is no secret that the main goal of most organizations is to maximize profitability and reduce costs to the minimum, but this matter is not achieved autom
... Show MoreThe current study included a detail morphological study of all parts of the species Ipomoea carnea Jacq. (Convolvulaceae) cultivated in different gardens, the roots, stems, leaves, flowers and fruit were studied in detail, also the pollen grains were studied and there are photographs for all the parts were putted.