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.
Ahmed ibn Imad ibn Yusuf al-Aqfhasi (808 AH / 1405 AD) is a small message that speaks about the Nile River in all its sides, despite its limited papers, but it is one of the manuscripts of the important geographical literature for its geographical, historical, religious and grammatical information. it was not limited to the information of the author alore, but taken from many sources below, which added to the importance of the fact that it has saved us the names of the sources that preceded him in mentioning this river with the names of its authors.The method of the Aqfhasi was characterized by scientific methodology in writing and clarity, with reference to some of the myths that people carried in their minds about the Nile River at tha
... Show MoreThe current study deals with the Islamic Arab of Mongolian invasion in the Island of Euphrates. We have exposed conditions of Levant before the Mongolian invasion and that includes situations of princess of Levant and their caliphates , they have been unaware the danger surrounding them and their country. It has also included the Islamic Arabic threat through the integration of Islamic Arabic cities residents in Levant to confront
تناول البحث اثر النساء في البيت العباسي وتأثيرهن الثقافي والعلمي في التراث البغدادي ، وانعكاسه على الواقع الاجتماعي الذي يعد بحد ذاته مظهر من مظاهر الانسجام والتلاحم بين الماضي والحاضر إذ تركن أثرا بارزا في الحضارة والعلم وأسهمن بصورة مباشره او غير مباشره في دعم وتطور الحضارة العربية الإسلامية .
This study deals with it the era of Taher Bin Al Hussein for his son Abdullah when preside Diyarbakir and Rabia in succession of ALMa`amoon Abbasi in the political and historical dimensions
This search aimed to show a series of converses that our prophet [peace be upon him] call ,some of them , (Kufraa) , and explain the meaning of (AI-kufr) that called on some works , so does it mean the apparent part or the pronunciation of(Al-Kufr) has another meanings ?
Abstract This research deals with the Al-Tossy contribution Islamic government and explain the directions of early shiaa political thoughts and knowing the opinions of Al-Shakh Al- Tossy in the Islamic Government
تناول البحث موضوعاً شديد الأهمية وهو الأمن الاجتماعي منظور اليه في سياق الحماية الجنائية لأمن الدولة والتحديات التي يتعرض لها بعد حصول تغيير حاسم في أساليب الحرب. كما يقدم البحث تقسيماً مختلفاً لأجيال الحروب نقتصر على اربعة منها استناداً إلى التغيير في أهداف الحرب الاستراتيجية وليس إلى مجرد وسائل ارتكابها لان هذه الوسائل لا تصلح لوصف التغييرات الحقيقية في أنماط الحروب والاهداف التي تسعى إلى تحقيقها. ويؤكد
... Show MoreIt was a women's importance in ancient societies، especially Mesopotamia as they worship mother goddess first entrance religious belief، which is undoubtedly a reflection of the vision of the community it represents the natural fertility cycle and Ishtar but realistic image of women dual and contradictory and nature of the code it by a thin love compassionate and another treachery and betrayal side and hatred. As we have seen in the Epic of Gilgamesh
Post-structural critical studies highlighted the importance of studying the texts surrounding the text as an important part in the process of receiving and understanding texts, and although this topic was dealt with by the ancient Arabs and Europeans, interest in it appeared clearly after the appearance of Gerard Genet's book (SEUILS), which separated it Text Thresholds. Or what he called paratexte, and dealt with them with interest as he reads them on books. With the development of semiotic studies, interest in paratexte studies began in a broader way and in various literary and non-literary texts, including journalistic texts. And since specialized magazines are one of the press releases that enjoy their privacy in terms of topics and
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استهدفت هذه الدراسة تحليل واقع الاقتصاد العراقي على خلفية تحليل القدرة التنافسية بما يفضي الى وضع ملامح عامة لإستراتيجية بناء للقدرة التنافسية الوطنية للنهوض بالواقع الاقتصادي. وقد افترضت الدراسة ان الاقتصاد العراقي يعاني من اخفاقات شديدة في الاداء لا تتصل بطبيعته ولاتعتبر سمة اصيلة من سماته بل هي ظرفية وطارئة رغم وجودها منذ عقود.
ان حالة الوهن المرافق للفعاليات الاقتصادية تتصل بغيا
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