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.
بات الفساد ظاهرة عالمية تهدد المجتمعات وبقائها ، وبدت الانقسامات المجتمعية تتضاعف في البلدان التي ينتشر فيها الفساد بمختلف أنواعه وتسمياته ، حيث استكشفت الدراسة بأن التشريعات الجنائية حرصت على تقرير نظام عقابي خاص لمواجهة جرائم الفساد مما استوجب بنا بيان المظاهر القانونية للفساد السياسي المتمثل بالرشوة الدولية والرشوة الانتخابية لان الفساد لم يعد متعلقا بالجانب الاقتصادي فحسب بل امتد إلى الجوانب الأخرى
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The Abbasid Caliphate generally paid attention to the financial aspect through the collection of resources , And also in terms of spending these resources
The main target of this research is to follow the stages of the emergence of
the idea of republican form of government from its very beginning , yet there
were many elements from different estates thinker , educated , few of heads of
clans . This first opportunity for the mobilization of politically-minded people
with fundamental activity like najei shokat . hussain al-rahal notable poet maruf
al-rasafi those who formed what so called the political elite who believed in
constitutional , democratic parliamentary republic , one of them was al-rahal who
called for a constitutional republic even before the emergence of the
constitutional movement in Iran and ottoman empire (1908).
The holy najaf become cultural cen
In this research I like to shed light on the mind because of its importance because it is what distinguishes Human from all other animals and that the question and status comes from his role in the formulation of knowledge and science where the machers agreed that the word of mind in its general sense is the source of thought and thought and the instrument of faith and philosophy , Then to the statement of the various stages pass
... Show Moreيتناول البحث الحماية المدنية للمستهلك في المرحلة السابقة على التعاقد الالكتروني
حضيت القيادة باهتمام كبير من قبل الباحثين ودورها الإيجابي في التأثير على الموظفين ونجاح المنظمات، في الآونة الأخير بدأت الدراسات تركز على الجانب المظلم للقيادة وتأثيرها على التابعين وبيئة العمل، وقد تم تحديد القيادة السامة بأنها أخطر الأساليب القيادية التي تتسبب بتكاليف مادية ومعنوية على المنظمات بمختلف جوانبها، ان القيادة السامة تأثر على دوافع المرؤوسين وقدرتهم على انجاز المهام، ورغبتهم في الاستمرار في
... Show Moredance that reflect deferent sides from life human , in this search ensure for the causation can the expressionistic dancing be development acting actor in Iraqis theatre ? so this search concept of section one composed of the search problem , and important the search and need it , aimed the search , lines search it composed of the lines time , place , and lines subject , and the searcher ended this section with practical terms . Section tow – theatrical lines form that composed of part one the dance kinds: the expressionistic dancing, is very important in analyses the symbol .
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Community peace is achieved in law-based states Constitutional institutions with competence and powers, and otherwise that peace is shaken and begins to collapse. The movement of individuals and groups in the State is regulated by law The law and its proper application without selectivity or exception, and then the sense of equal opportunity and equal rights grows every citizen looks at his spouse, what he has, and when he is unbalanced, a sense of frustration and stealing of rights is generated Societal peace suffers from the shocks of instability and what is reflected in the surrounding environment. Instead of production, demolition takes place, which impedes the achievement of the required peace.
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