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.
This research is an attempt to study and evaluate the maintenance function at Factory 7 - The State General Company for Leather Industries, and to design a computerized preventive maintenance system to design and to analyze preventive maintenance. To accomplish the objectives of this research, data were gathered and analyzed according to the reliability engineering criteria for the period 2/1– 30/6/2005, then a preventive maintenance plan was designed for each machine of the sample study using the computerized system designed in this research. A Monte Carlo Simulation methodology was used for the purpose of evaluating the performance of the preventive maintenance plan of each machine for one year. The simulation res
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Persuasion is an indispensable skill in everyday life; that is why, it has aroused researchers’ interest. This study aims to investigate the most frequently used persuasive strategies in texting WHO COVID-19 Virtual Press Conferences and explore how these strategies are employed to achieve persuasive messages.To this end, a text of WHO COVID-19 Virtual Press Conferences has been chosen randomly to be analyzed based on Dillard and Shen’s (2013) “Persuasive strategies in Health Campaigns”. A qualitative method has been adopted in analyzing the selected data to investigate the credibility and validity of the persuasive strategies used in such a domain. Findings have shown that most of the persuasive appeals based on the adopted mode
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Manuscript (Tuhfat Al-Ashaba and the Nuzha Al-Kulbab) by Ahmed bin Ibrahim Al-Hanafi Al-Suruji (d.710 AH / 1310 AD), one of the important manuscripts as an encyclopedia characterized by the diversity of its topics
هدف البحث إلى إعداد تدريبات الثبات المحوري باالنقباض المتحرك لالعبين الشباب بكرة القدم، والتعرف على تأثير تدريبات الثبات المحوري باالنقباض في التوازن المتحرك والقوة المميزة بالسرعة للرجلين والمناولة المتوسطة لالعبين الشباب بكرة القدم، واعتمد المنهج التجريبي بتصميم المجموعتين ً التجريبية والضابطة على عينة بلغت )24 ( العبا بأسلوب ً من فئة الشباب بكرة القدم اختيرت عمديا الحصر الشامل وبنسبة )100 %( من نادي الشرط
... Show MoreBehavioral and emotional disorders represent one of the commonest problems facing children in particular and disturbing their parents and educators in general. This is because Iraqi people have long been living in difficult conditions and faced various terrorists’ operations, such as killing, destruction, robbery, and looting. Such operations are said to be one of the reasons that leads to the development of such disorders, and may negatively affect the psyche of the child and be reflected on his behavior as represented by playing with the IPad for hours, and suffering from nightmares. Accordingly, the current research aims to examine specifically the commonest negative behavioral disorders among kindergarten children during the post-t
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Research questions start from the fact that what the Arab origins of education indicted . First question are :
- To what extent the subject of assets acquired a specific meaning in the Arabic books and educational subjects ? Is these selections are reflected on the classification of assets and their types ?
- What’s the nature of the content ? .Is there a consistency between the meaning and content ?
- What entrances handling and curriculum approach and tactics are in those books ?
- Is the assets subject introduced within the grade best suited ?
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... Show MoreIt is a common Knowledge that adverbs in Turkish languages can modify verbs, adjectives, nouns or other adverbs. Moreover, adverbs can determine the meanings of nouns and verbs in a sentence as far as time, place, manner, quantity and interrogative are concerned. The present study debates adverbs’ functions in Namiq Kamal’s play Vatan yahut Silistre.
The study sheds light on the author’s use of the adverbs to describe the required theatrical actions of the play and to convey his reflections and thoughts easily to the auidence. One of the main hindrances encountered in conducting the study is the shortage of the upto date academic resources necessary for
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The research aimed to study the role that the media play in shaping the public knowledge of human rights issues among the people of Kirkuk, which will be the focus of the study. The research was conducted by applying a survey panel to a random sample of the city's audience. The research dealt with the theoretical aspect of a theory that relied on the media, and the loans provided by the theory, on the basis of which the research was conducted and the research problem was determined based on a major question: What is the role that the mass media play in developing the knowledge of members of the public on human rights and the relationship between the intensity of view in that, as well as the identification of the effect of two variables G
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اهمية البحث هي مرحلة نمو وبناء اجهزة الجسم للاعبين الاشبال واعداد تدريبات بأسلوب التدريب الدائري لبناء التحمل لتطوير بعض القدرات الحركية والمهارية لدى اللاعبين الاشبال بكرة القدم , حيث لاحظت الباحثة ضعف في مستوى الاداء الحركي ارتأت اعداداً بدنيا ومهارياً منذ مرحلة البناء الأولى للاعب الفئات العمرية , واستخدم الباحث المنهج التجريبي بالاختبار القبلي والبعدي للمجموعتين التجريبية والضابطة لملائمته لطبيعة ال
... Show MoreThe interleukin-1 family has multifaceted roles in men٫s reproductive syste. Out of these is interleukin-1 receptor antagonist (IL-1RN) which exists in men gonads, and in case of infection and inflammatory process, its activity is increased. The current study aims to verify a possible linkage of Variable Number Tandem Repeat (VNTR) polymorphism of the IL-1RN gene with human men infertility. The study groups enrolled included 100 infertile men and 100 fertile and healthy men. Their seminal fluids were subjected to analysis. Also peripheral blood samples were collected for the assessment or detection of polymorphic Variable Number Tandem Repeats (VNTR) polymorphism of interleukin-1 receptor antagonist gene (IL-1RN). Two a
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