Background: The demand for esthetic orthodontic appliances is increasing; so the esthetic orthodontic archwires were introduced. Among them, Teflon and Epoxy coated stainless steel archwires. The amount of force available from the archwire depends on the structural properties and susceptibility to corrosion. All metallic alloys are changed during immersion in artificial saliva, chlorhexidine mouthwash andtoothpaste, but their behaviors differ from one type to another. They corrode at different rates, which lead to decrease the amount of force applied to the teeth. This in vitro study was designed to evaluate the corrosion pits in stainless steel archwires coated with Teflon and with Epoxy in dry and after immersion in artificial saliva, chlorhexidine(0.2%( (Parodontax) and toothpaste media (Sensodyne) for (1, 7 and 28) days intervals. Moreover, this study is intended to compare the corrosion pits for each type of archwires at these different media among all intervals. Materials and Methods: In this study, two hundred forty pieces of orthodontic wires of Teflon (Hubit) coated Stainless steel (120 pieces) and epoxy (Orthotechnology) coated Stainless steel (120 pieces), rectangular in cross section, size (0.019 x 0.025) inch and 15mm in length divided into four groups according to immersion media: (dry environment group, artificial saliva group, chlorhexidine group and toothpaste group). The atomic force microscope was used to measure the corrosion pits for all samples at dry and wet conditions and after different immersion periods. Results: Statistical analysis showed that there was a highly significant increase in the corrosion pits of Teflon coated stainless steel archwires (P ≤ 0.05) in wet environment at 28 days immersion period.The highest corrosion pits were found in the toothpaste medium for the two archwire types at 28 days immersion period. Conclusion: We can conclude that Epoxy coatedstainless steel archwires are indicated to be used above Teflon coated stainless steel archwires in terms of corrosion resistance. IfTeflon coated stainless steel archwires should to be used, they should be change in shorter periods than Epoxy coated stainless steel archwires type Key words: Esthetic coated archwire, corrosion, Teflon, Epoxy, wet environment, AFM.
Automatic Programming Assessment (APA) has been gaining lots of attention among researchers mainly to support automated grading and marking of students’ programming assignments or exercises systematically. APA is commonly identified as a method that can enhance accuracy, efficiency and consistency as well as providing instant feedback on students’ programming solutions. In achieving APA, test data generation process is very important so as to perform a dynamic testing on students’ assignment. In software testing field, many researches that focus on test data generation have demonstrated the successful of adoption of Meta-Heuristic Search Techniques (MHST) so as to enhance the procedure of deriving adequate test data for efficient t
... Show MoreBuilding numerical reservoir simulation model with a view to model actual case requires enormous amount of data and information. Such modeling and simulation processes normally require lengthy time and different sets of field data and experimental tests that are usually very expensive. In addition, the availability, quality and accessibility of all necessary data are very limited, especially for the green field. The degree of complexities of such modelling increases significantly especially in the case of heterogeneous nature typically inherited in unconventional reservoirs. In this perspective, this study focuses on exploring the possibility of simplifying the numerical simulation pr
The research aims to determine the role of Entrepreneur decision-making in its dimensions in improving the activities of Ambidexterity performance in its dimensions in the researched company. The importance of the research is also evidenced by assisting the oil products distribution company/session in directing the interest of the researched company because it has a prominent role in the Iraqi industrial community for the Entrepreneur decision-making variable that Contributes to building sustainable competitive advantage. This will happen when the company has an Entrepreneur orientation and a good strategic plan is built by the smart leaders in the researched company The researcher adopted the method of the analyti
... Show MoreIn 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
... Show MoreThe 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 MoreThe aim of this research is to show the level of banking leadership trends in the importance of organizational confidence and its reflection in the dimensions of the strategic position the research was applied in a bank (Al- Mansour Investment, Business Bay), and the Questionnaire Was adopted as a tool to collect data and information from the number of the sample (15) who are in allocation (Department Manager, Department Manager Department Manager, Division Officer, Unit Officer) and he used the statistical program (spss) to calculate (standard deviation, arithmetic mean, percentages, regression, analysis,F-test coefficient of determination R2, Coefficieent, square Kay and the research reached a number of conclusions, the mos
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The current research is aimed at analyzing the impact of the dimensions of Job involvement of all of (the enthusiasm, the Devotion, Assimilation ) in the Crystallize organizational Identification across the dimensions of (organizational loyalty, membership, similarities) and was named the Middle East, the Iraqi Investment Bank room to look as the research community of staff adopted in the bank, to be applied to a Random sample of (100) employees working in the said bank, and developed for the purposes of data collection, a questionnaire form included three axes covered (32) paragraph of the measure, which is included adopted Liekrt Quintet for the
... Show MoreInnovative various Schiff bases and their Co(II), Ni(II) and Cu(II) and Hg(II) compounds made by the condensation of 4-amino antipyrine with derived aminobenzoic acid (2-aminobenzoic acid, 3-aminobenzoic acid, and 4-aminobenzoic acid ) have been prepared by conventional approaches. These complexes were described by magnetic sensibility analysis, FT-IR spectra, and molar-conductance and elemental analysis. Analytical values appeared which the mixed-ligand complexes presented ratio about 2:1 (ligand: metal) with the chelation 4 or 6. The prepared compounds offered a good effect on the organisms; bacteria Staphylococcus-aurous, Escherichia-coli and fungi C. albicans, A. niger. Also, the biological products signalize which the mixed compl
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