Background:sThe aims of this study were to evaluate and compare the ability of three different techniques to obdurate simulated lateral canals, evaluate the effect of the main canal curvature on obturation of lateral canals and compare the gutta-percha penetration between coronal and apical lateral canals. Materials and methods: Resin blocks with 30 straight and 30 curved were used in this study. Each canal has two parallel lateral canals. The main canal has 0.3 mm apical diameter and 0.04 taper. The canals were divided into six groups according to canal curvature and obturation techniques used (n=10): Groups C1 and C2: straight and curved canals obturated with continuous wave technique using E&Q masterTM system. Groups O1 and O2: straight and curved canals obturated with Obtura II. Groups T1 and T2: straight and curved canals obturated with Thermafil obturators. Soapy water was used to simulate sealer in all obturations performed. The depth of gutta-percha penetration into lateral canals was measured using computerized stereomicroscope. Results: There were very highly significant differences between the obturation techniques at each lateral canal level in both straight and curved canals. Continuous wave using E&Q masterTM system exhibited the greatest gutta-percha penetration into lateral canals with very highly significant difference from both other techniques at majority of lateral canals. There was non- significant difference between Thermafil and Obtura II except at coronal lateral canal of straight main canals where the difference was very highly significant. The gutta-percha depth was greater in coronal than apical lateral canals in all groups of both straight and curved canals, and gutta-percha depth was greater in straight than in curved canals within each obturation technique. Conclusion: This study showed that all the three obturation techniques used were able to obturate simulated lateral canals with the continuous wave technique being the best. Gutta-percha depth was less in the apical than the coronal lateral canals. Canal curvature can influence the gutta-percha depth.
The objectives of this study revolve around identifying the extent of funding impact on the future of the printed Iraqi press, and whether it threatens their chances of survival, stating the extent of technological development on the income of the printed newspaper, and identifying the causes of the financial crisis on the newspaper.
This research is classified as descriptive research, and the researcher used the survey method, and adopted the questionnaire of the views of the contactors, in five Iraqi newspapers (morning - extent - time - the way of the people - the call).
The research community included (68) respondents, whereby the comprehensive inventory method was used to define the research community, and the researcher used
Silver nanoparticles synthesized by different species
The present study aimed to investigate the histology of the testis in golden hamster during 1, 28 and 60 day of old. Tissue samples were processed, sectioned and subjected to specific stains to reveal histological details. Observation of one day old showed the testicle enclosed by undifferentiated thin layer of testicle capsule which consisted of undifferentiated myoblasts and fibroblasts small size seminiferous tubules appeared, one layer of spermatogonium cells (Type-A) which revealed mitotic figures, at 28 day old the capsule was consisted of thick outer fibromuscular layer and thick inner vascular layer that revealed encouraged blood vessels and cells, Spermatogonial cells type-A & B appeared as large
... Show MoreIn this research, damping properties for composite materials were evaluated using logarithmic decrement method to study the effect of reinforcements on the damping ratio of the epoxy matrix. Three stages of composites were prepared in this research. The first stage included preparing binary blends of epoxy (EP) and different weight percentages of polysulfide rubber (PSR) (0%, 2.5%, 5%, 7.5% and 10%). It was found that the weight percentage 5% of polysulfide was the best percentage, which gives the best mechanical properties for the blend matrix. The advantage of this blend matrix is that; it mediates between the brittle properties of epoxy and the flexible properties of a blend matrix with the highest percentage of PSR. The second stage
... Show Morehis study aimed to evaluate the effects of different doses of melatonin on liver function in adult rats. Eighteen Wistar adult albino rats (Rattus norvegicus), approximately 13–16 weeks old and weighing 230 ± 10 g, were randomly divided into three groups (n=6 per group) and treated orally for 30 days as follows: Group A1 received 10 mg/kg body weight (B.W) of melatonin; Group A2 received 20 mg/kg B.W of melatonin; and the control group (Group A) received distilled water. At the end of the treatment period, blood samples were collected via cardiac puncture, and serum was separated for biochemical analysis. Parameters assessed included oxidative stress markers (malondialdehyde (MDA), reduced glutathione (GSH)) and liver enzymes (aspa
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Shear and compressional wave velocities, coupled with other petrophysical data, are vital in determining the dynamic modules magnitude in geomechanical studies and hydrocarbon reservoir characterization. But, due to field practices and high running cost, shear wave velocity may not available in all wells. In this paper, a statistical multivariate regression method is presented to predict the shear wave velocity for Khasib formation - Amara oil fields located in South- East of Iraq using well log compressional wave velocity, neutron porosity and density. The accuracy of the proposed correlation have been compared to other correlations. The results show that, the presented model provides accurate
... Show MoreThe current research aims to reveal the level of satisfaction of the mentors with the evaluation of their performance according to gender (male - female) and to formulate the predictive equation for the level of performance (dependent variable) from knowing the level of satisfaction with the evaluation (independent variable). (16 paragraphs) contains alternatives to the answer that measures the level of satisfaction (weak, medium, and high) (1,2,3), that is, with a hypothetical average of (32). It consisted of 100 educational counselors consisting of 45 males and 55 females, the results of the research concluded that the level of satisfaction with performance is below the mean when compared with the hypothetical average of the scale of s
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