Background: The bond strength of the root canal sealers to dentin seems to be a very important property for maintaining the integrity and the seal of root canal filling. The aim of this study was to evaluate the shear bond strength of four different obturation systems using push-out test. Materials and methods: Forty straight palatal roots of the maxillary first molars teeth were used in this study, these roots were instrumented using crown down technique and ProTaper system, instrumentation were done with copious irrigation of 2.5% sodium hypochlorite and 17% buffered solution of EDTA was used as final irrigant followed by distilled water, roots were randomly divided into four groups according to the obturation system (ten teeth for each group): Group I: AH26 sealer and lateral condensation technique, Group II: AH26 sealer and single cone obturation technique, Group III: AH26 sealer and thermafil obturation technique and Group IV: RealSeal SE sealer and lateral condensation technique, the roots then stored in moist environment at 37°C for one week The roots were embedded in clear acrylic resin and each root sectioned into three levels apical, middle and cervical. The measurement of each section was taken to prepare the supporting jig for the sections and the punch used in pushout test, the bond strength was measured using computerized universal testing machine each section fixed in the machine so that the load applied from apical to cervical direction at 0.5mm/min. speed and the computer drew curve to show the higher bond force before dislodgment of the filling material. These forces were divided by the surface area to obtain the bond strength in MPa. Results: Statistical analysis was performed and the result showed avery highly significant differences between the four obturation systems at each level and there were non significant differences between all level apical, middle and cervical within each obturation system except a significant difference found between cervical and apical level in single cone obturation system. Conclusion: This study showed that the shear bond strength of AH26 sealer was higher than RealSeal SE sealer when the same obturation technique was used. The shear bond strength was affected by the obturation technique and lateral condensation technique showed higher bond strength than thermafil and single cone obturation technique when the same type of sealer was used and the bond strength was not or little affected by the tooth level
In drilling processes, the rheological properties pointed to the nature of the run-off and the composition of the drilling mud. Drilling mud performance can be assessed for solving the problems of the hole cleaning, fluid management, and hydraulics controls. The rheology factors are typically termed through the following parameters: Yield Point (Yp) and Plastic Viscosity (μp). The relation of (YP/ μp) is used for measuring of levelling for flow. High YP/ μp percentages are responsible for well cuttings transportation through laminar flow. The adequate values of (YP/ μp) are between 0 to 1 for the rheological models which used in drilling. This is what appeared in most of the models that were used in this study. The pressure loss
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The current phase distinguish by the rapid scientific development, which pushes individuals to have the necessities of scientific and practical life through the proper scientific thinking which contribute to the development of invention and creativity away from memorizing and indoctrination and encouraging individuals to looking for information and then attempting to process and develop these information instead of being a passive receiver. The investment of minds becomes the logical investment in all societies by preparing the citizen to become able to face life changes and its necessities. It is very important to take care of individuals and develop their mental abilities and thinking skills. The constructive strateg
... Show MoreThis study was conducted at the poultry research station to the office of Agricultural Research / Ministry of Agriculture / during the period 4/1/2016 to 5/5/2016 and 336 one-day-old Ross308 chicks were used, and fed on diets provided with dried dill (Anethum gravelens) at levels 0.4, 0.6 and 0.8% for treatments D2, D3 and D4, respectively, and they were compared with the control treatment D1. Each treatment included three replicates in each replicate contain 28 birds, in order to study the effect of adding different levels of dried dill plant on the productive performance and some characteristics of the carcass for broilers. The results showed a significant increase (p<0.05) in the average body weight at 5 weeks of age for the treatments (
... Show MoreLabrotary experiment was conducted to study the effect of different levels of nematode population densities of Meloidogyne spp on seed germination percentage and seedling characteristics of Vigna sinensis, Ahelmoschus esculentus, Cicer arietinum, Helianthus annuus and Rap-hanus sativus. Four different levels of nematode populat-ion densities ranged from 1 to 4 prepared from radish in-fected roots and used as inoculating agent to infect all seed types in the experiment Seed germination percentage of Vigna sinensis and Ablemoschus eseulentus were highly reduced (at 0.01 level of significance) with increased nematode population level from 1 to 4. Seedling length of the remaining seed types were significantly reduced (at 0.01 level of signif
... Show MoreCarnitine is a regulatory amino acid, necessary for the metabolism of long-chain fatty acids in the ß - oxidation, and it is important in the organization of the work of the blood brain barrier, and is very important in the treatment of infertility and sexual apathy. This study was conducted at the Poultry Farm of the Department of Animal Resource, College of Agriculture, University of Baghdad during the period from 15/2/2011 to 1/8/2011. The aim of this study was to investigate the effect of dietary supplementation with different levels of L - carnitin e on semen characteristics of guinea fowl male. A total of 24 guinea fowl male, 30 weeks of old were used in this study. Birds were randomly distributed into 4 groups (C0, C100, C200, C300)
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This study was carried out at Poultry Research Station, State Board of Agricultural Research, Ministry of Agriculture for the period from 27 September 2014 to 9 November 2014 to evaluate the Supplementation of different levels of Conjugated Linoleic Acid (CLA) on productive performance of broiler. Four hundred eighty chicks (Ross-308),one day old were randomly distributed to four dietary treatments for 42 days of age with 3 replicates/vtreatment (40 bird/replicate). Experimental treatments were as follow; T1 (Control diet) without supplement, while the treatment T2,T3 and T4 were Supplemented with 1, 1.5, 2 g CLA /kg diet respectively. The results showed significant (P ≤ 0.05) increased in mean of body weight, weight gain, ave
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The current research focuses on a major problem: the weak role of disclosing corporate information in the application of laws, regulations and instructions related to the application of corporate governance principles weakens the ability to protect the rights of shareholders and investors in companies listed on the Iraqi Stock Exchange and the study aims to study and analyze the role of disclosure and transparency in achieving the necessary protection to ensure the rights of shareholders. The study was applied to a sample of (42) analysis samples representing (84%) of the total questionnaires distributed to investors and shareholders in all listed companies in the Iraqi Stock Exchange. The results confirm the shareholder's right to obtai
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Motives: Baghdad is the capital city and an important political, administrative, social, cultural and economic centre of Iraq. Baghdad’s growth and development has been significantly influenced by efforts to accommodate various needs of its steadily growing population. Uncontrolled population and urban growth have exerted negative effects in numerous dimensions, including environmental sustainability because urban expansion occurred in green spaces within the city and the surrounding areas.Aim: The aim of this study was to examine the planning solutions in Baghdad’s green areas in the past and at present, and to identify the key changes in the city’s green areas, including changes in the ratio of green urban spaces to the tota
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The current study aims to compare between the assessments of the Rush model’s parameters to the missing and completed data in various ways of processing the missing data. To achieve the aim of the present study, the researcher followed the following steps: preparing Philip Carter test for the spatial capacity which consists of (20) items on a group of (250) sixth scientific stage students in the directorates of Baghdad Education at Al–Rusafa (1st, 2nd and 3rd) for the academic year (2018-2019). Then, the researcher relied on a single-parameter model to analyze the data. The researcher used Bilog-mg3 model to check the hypotheses, data and match them with the model. In addition
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