Laser etching may be an alternative to acid etching of enamel and dentin. Several characteristics of irradiated dental hard tissues have been considered advantageous, microscopically rough surfaces without demineralization, open dentinal tubules without smear layer production and dentin surface sterilization. The aim of this study is to determine and compare histology the microleakage in class V cavity restored with a light cured composite after conditioning the samples(tooth surface) with 1-acid etching, 2-Q-switched Nd:YAG Laser etching and finally 3- acid and laser etching. Materials and methods: Twenty four non carious human extracted teeth were used in this study. The samples were equally grouped into four groups of six teeth each. A class V cavity was prepared. In group I, tooth surface was etched with a 37% phosphoric acid gel. In group II, the tooth surface was conditioned using a pulsed Nd:YAG Laser alone with a wavelength of 532 nm. The parameters were of pulse energy 60 mJ, pulse repetition rate 6Hz and energy density was 0.48 J/cm2. In group III, the tooth surface was treated with Nd: YAG Laser and then was etched with phosphoric acid. In group IV, the surface was treated with 37% phosphoric acid then irradiated with Nd: YAG Laser; with the same parameters and concentration mentioned in group I and II. The samples immersed in 1% basic fuschin dye to mimic the normal stains in oral cavity and the sections were examined by a stereomicroscope and the readings were scored. Results: The results showed that group IV, in which the surface was treated with 37% phosphoric acid and then irradiated with Nd: YAG Laser) recorded the least microleakage of the four groups, where group III, in which the tooth surface was treated with Nd: YAG Laser and then was etched with phosphoric acid)recorded reasonable results better than group I (group I tooth surface was etched with a 37% phosphoric acid gel) or group II , in which the tooth surface was conditioned using a pulsed Nd:YAG Laser alone) Conclusion: The use of Q-switched Nd:YAG laser in etching the tooth surface was so effective that it can be used in treating or conditioning the tooth surface to enhance bonding and the best parameters among the tested samples were pulse energy of 60mJ, pulse repetition rate of 6Hz and energy density 0.48 J/cm2.
The theory of the epic theater has received wide attention by filmmakers around the world because of its great impact on the artistic work of the theater and its relationship with societies, and among these directors the Iraqi directors have been influenced by the epic theater and its applications in the show.
In order to find out the effectiveness of these influences on the Iraqi director, I found the need to do this study, which was divided into an introduction and a theoretical framework that included two topics. The first topic (Philosophical References and the Intellectual Foundations of the Epic Theater Theory) deals with the philosophical foundations that crystallized the epic theory of Burch and the mechanism of working
Performance measures are a central component of management control system, making good planning and control decisions requires information about how different subunits of organizations have performed. To be effective, performance measures (both financial and nonfinancial) must also motivate managers and employees at all levels of organization to strive to achieve organization goals.
To give aclear picture about performance must be used compound measure, that was best than single measure.
Altman model can be used as a compound performance measure that measures the performance by tied a sum of variables, due to make weight for every variable to reach for performance.
Britain found itself at the end of the nineteenth century in front of many obstacles within Europe, it is to hold the coalition Russian Franco in 1894, and what form of threat to the interests of Britain in its colonies outside Europe, as well as the development of other European countries in military and economic aspects such as Germany and the United States and others. As she was defying the fleet of Britain, Germany, and the last has a naval fleet was able to protect all the way Britain and its colonies throughout the nineteenth century
Free water surface constructed wetlands (FSCWs) can be used to complement conventional waste water treatment but removal efficiencies are often limited by a high ratio of water volume to biofilm surface area (i.e. high water depth). Floating treatment wetlands (FTWs) consist of floating matrices which can enhance the surface area available for the development of fixed microbial biofilms and provide a platform for plant growth (which can remove pollutants by uptake). In this study the potential of FTWs for ammoniacal nitrogen (AN) removal was evaluated using experimental mesocosms operated under steady-state flow conditions with ten different treatments (two water depths, two levels of FTW mat coverage, two different plant densities and
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A financial analysis tool such as financial rations concentrates on explanation of financial statement and using them in the evaluation of company profiles and fixing taxable profits, by analyzing final calculation, explaining their results and studying relationships between a group of financial lists 'elements in a specific period and the trend of their relationships in percentage from so, financial analysis is considered on important instrument for tax analytical test procedures through studying and evaluating financial data in order to get proper information which is needed to make sure of credibility and reliability of statements submitted by the taxpayer and the satisfaction of the tax analyzer in the credibility of these statements
... Show MoreThe audit committee has received considerable attention from international institutions and researchers as a result of financial failures and the collapse of major international companies, especially cases of manipulation and misinformation in the financial statements, due to the role played by one of the mechanisms of control of economic entities to increase disclosure and credibility of information published, In overseeing the preparation of financial reports, following up the internal auditing functions, supporting the external auditor and enhancing his independence, and strengthening the shareholders' confidence in the economic entity. The two researchers prepared the applied side of the research by applying a proposed model based on
... Show Moreأن أزدياد أعداد الطلبة في معظم دول العالم ، والتوسع في التعليم العالي ، أدى الى أستيعاب أعداد كبيرة في المؤسسات التعليمية من حملة الشهادات العليا الماجستير خاصة والدكتوراه ، وأن برامج الدراسات العليا وضعت لأعداد باحثين مختصين في مجالات عدة منها التدريس وما يتطلبه من مهارات مختلفة ، فأن قسماً منهم ليست لديه المعرفة النظرية والتطبيق العملي والمهارات اللازمة لأستخدام طرائق التدريس والتقنيات التربوية أث
... Show MoreSupply Chain Management (SCM) attempts to a create a synchronization of the firm’s processes and those of the supplier to match the flow of materials, services, and information with the customer demand. Due to its importance, the SCM has become inevitable to modern companies. Therefore this research work has been conducted to set a theoretical and applied basis to assist the 1 AYAR factory in adopting the Electronic Supply Chain (e-SC). To accomplish that the searchers applied many tools such as: quantitative and qualitative analysis, process analysis, Visual Basic software, Monte Carlo Simulation to simulation the designed supply chain to compare its performance against the actual performance of the current supply chain
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