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
Health and safety problem can be described by statistics it can only be understood by knowing and feeling the pain, suffering, and depression. Health and safety has a legal responsibility to protect it for everyone who can affect in the workplace. This includes manufacturers, suppliers, designers and controllers of work places and employees. Work injury is one of the major problems in manufacturing and production systems industries; it is reduced production efficiency and affects the cost. To gain flexibility from a traditional manufacturing system and production efficiency, this paper is about the application of estimating technology to preview and synthesis of Lost Time of Work Injuries in industry systems aims to provide a safe workin
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An experimental study is carried out on the effect of vortex generators (Circular and square) on the flow and heat transfer at variable locations at (X = 0.5, 1.5, 2.5 cm) ahead of a heat exchanger with Reynolds number ranging from 62000< Re < 125000 and heat flux from 3000 ≤ q ≤ 8000 W/m2 .
In the experimental investigation, an apparatus is set up to measure the velocity and temperatures around the heat exchanger.
The results show that there is an effect for using vortex generators on heat transfer. Also, heat transfer depends on the shape and location. The circular is found t
... Show MorePurpose: To determine the impact of service encounter in stimulating voluntary customer behaviors.
- Approach / methodology: It was selected a sample of customers Bank Iraqi Trade (TBI) was (105) individual, using a questionnaire designed in the light of previous studies, was drafted scale and tested in the light of a group of statistical methods developed (reliability coefficient, reliability coefficient composite, convergence). Then test hypotheses through structural equation modeling.
- Results: The behaviors and characteristics of the service provider in effect urged bank customers to perform voluntary extra, as the service environment service encounter
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This research aims to apply the Performance Focused Activity Based Costing System in the offices of scientific and advisory services at the University of Technology for the purpose of measuring the cost of services provided by these offices in order to reduce costs. To test the hypothesis of the research, the research was applied in the consulting offices of the University of Technology through the financial statements for the year ending 12/31/2017 of the Scientific and Consulting Services Office of the University of Technology, because the data of these years were issued and audited by the Federal Office of Financial Supervision.
A number of
... Show MoreThe intensification of competition among all companies and at different levels has become necessary for every company need to continue to improve its performance in order to be able to face the competition and stay in the market. To achieve this, we must rely on the company's accounting information more accurate and appropriate and provided in a timely manner, for the purpose of use in planning and decision making.
So there must be information systems that help the administration to continuous development and improvement of the performance of companies in general, and this is what you need Jordanian companies, especially after the accession of Jordan to the field
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The research problem lies in: The use of positive and negative flexibility exercises to develop the special strength of the 400m hurdles player, that some young people face weakness and a problem in performance, which requires the need to prepare special exercises for physical and skill numbers using the types of exercises that have resilient strength, flexibility and have the effect on developing and determining the level of physical and skill performance. To develop 400m hurdles, special strength, explosive power and the characteristic velocity of arms and legs. Research aims: 1. Preparing positive and negative flexibility exercises to develop the special force and the effectiveness of 400m youth barriers. 2. Identify the effect of exerci
... Show MoreSummary Kidney transplantation is widely performed nowadays as an optimal treatment of end stage kidney diseases. Complications such as stenosis in graft renal arteries anastomosis may occur. Different suturing techniques are available for renal artery anastomosis. We aimed to compare the incidence of renal artery stenosis of the transplanted kidney when two suture techniques (continuous or interrupted) used for renal artery anastomosis. Therefore, a retrospectively comparative study was conducted on 44 patients managed with kidney transplantation during the years 2009-2011. Patients assigned into two groups; first group included 20 patients namely, continuous suture group, and the second group included 24 patients in whom the allograft art
... Show MoreThe aims of study is to detect the inhibitory effect of Saccharomyces boulardii and Lactobacillus acidophilus on Escherichia coli that has been isolated from recurrent urinary tract infection in women. The sensitivity of E.coli isolates to antibiotics had been studied and the most resistant E.coli isolate to antibiotics had been studied .The cup assay was used on nutrient agar and Muller-Hinton agar to detect the inhibitory activity for each S.boulardii yeast grown on YEGP media and L.acidophilus grown on MRS media in which the result showed a high inhibition activity for each of them .Also in this study the adhesion property of E.coli had been evaluated in the presence of S.boulardii at concentration of 1×109 and L.acidophilus at conc
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