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
The study aimed to identify the role of the teacher in confronting intellectual extremism in high school students, and identify the differences of statistical significance in the role of teacher in confronting intellectual extremism in secondary school students according to gender variable (males, females) and the duration of service (less than 5 years more than 5 years), the sample was consisted of (100) teachers with (50) male and (50) female in the city of Bayaa, Dora and Sadiya, the measure of intellectual extremism was applied by the researcher, and the study reached a role of the teacher in facing the intellectual extremism at Secondary school students, and the existence of differences of statistical significance in the role
... Show MoreThis research aims to identify the effectiveness of modern media technologies represented by satellite TV in the development of good citizenship values when students. To achieve this purpose were selected a sample of 44 students in the Department of Electrical technologies in Technical Institute in Nasiriyah in southern Technical University during the school year (2015-2016).
Was determined the general objectives of the use of modern media techniques represented satellite TV is to promote the values of good citizenship among the sample of students in order to make them good citizens in the community could contribute to the development and upgrading it. And put the general plan of research. Promising researchers measure of good citizen
In spite of the disappearing of a clear uniform textbook for teaching ESP at different departments and different colleges in both scientific and humanistic studies, the practitioners at those departments and colleges have to teach translation as one of the important requirements to pass the English language exam. The lack of defined translation activities is a noticeable problem therefore; the problem of teaching translation is diagnosed in that the students lack the ability to comprehend the text in English language and other translation knowledge and skills.
The study aims to suggest a translation strategy and then find out the effect of the translation strategy on ESP learners’ achievement in translation. A sample of 50 stud
... Show MoreThe present paper attempts to establish a distinction between Exochomus negripennis (Er.) and E. quadripustulatus L., depending on the characters of femoral line, male genitalia and spermatheca.
A concept of indoor solar illumination is described and simulated. The solar illumination system is composed of a tracking primary reflector, a selective secondary reflector, a visible light guide and a scattering solid glass tube fixture. Each part of the solar illumination system is optically suited and compatible with other parts to realize high efficiency. The simulation is conducted for Baghdad city for a library hall. Two major days over a year are chosen to investigate the illumination system for acceptable visible light level for reading hall. The two days are: summer solstice day and winter solstice day at 8:00 AM and 12:00 PM for each. Research results showed that the design of the solar system is achieved on the base of minimu
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The gas chromatography (GC) method in analytical chemistry is a quick and accurate method to detect volatile components like ethanol. A method for determining volatile components known as Headspace chromatography (HS-GC) was developed along with an internal standard method (ISM) to identify ethanol in fermented broth in the laboratory. The aim of this research is determining the concentration of ethanol in fermented broth using capillary column (ZB-1). This method can analyze ethanol concentrations in the fermented medium broth ranging from 10 to 200 g/L. The validation of this method was done in order to obtain the results to be of high precision and the significant, precision was represented as the relative standard deviation (RSD) which
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This research was carried out to reveal the the technique of the recitation in this story including a preface, introduction, two chapters and the conclusion. the introduction consisted of the problem, significance , purpose and limitations of research. The preface included two paragraphs. The first included a meta-recitation of terminology and semantic. The second paragraph devoted to show the cultural identity of Hussein Rahim. The first chapter aimed to reveal the reality and the imaginary in the story of Na'lat Al Hakawaty (storyteller's curse). The second chapter aimed to study the strange arguments in the story. The research concluded the conclusion by presenting the results for attaching them with the margins, and the references
... Show MoreSome physical properties enthalpy (?H), entropy (?s), free energy (?G),capacities(?cp?) and Pka values) for valine in dimethyl foramideover the temperature range 293.15-318.15K, were determined by direct conductance measurements. The acid dissociation at six temperature was examined at solvent composition x2) involving 0.141 of dimethyl foramide . As results, calculated values have been used to determine the dissociation constant and the associated thermodynamic function for the valine in the solvent mixture over temperatures in the range 293.15-318.15 k. The Pka1, and Pka2 were increased with increasing temperature.
The aims of research is diagnose and indicate the role of fairness in the work of accounting, which is important in reducing the unacceptable practices to manage earnings by economic units, As well as the interpretation and indicate Ethical inside in the accounting and accountants in particular practices in the area of earnings management to reduce the negative effects of the practice and display the results mentioned acts according to what is supposed to be for the purposes of service users, Researchers have identified that one hypothesis, that "Fairness of accountants in of their work accounting lead to a reduction of earnings management practices". The results suggest that the accounting practices that lead to the manipu
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