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.
By reading the book (Endless Forms Most Beautiful: The New Science of Evo Devo) by Sean B. Carroll, new horizons opened up about the nature of the formation of the living organism. Although he presented the idea that the artist was influenced by the material assets of nature in his holographic art formations, the new science of Evo-Devo (Evolutionary Developmental Science) provided models worth standing on when comparing the similarity of the formation of living organisms on the one hand, and the formation of works of art with holographic organic bodies on the other. But the excitement lies in the fact that the formation of living natural organisms is often driven by subtle intelligent mechanisms that are different from the mechanisms us
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This research aims to reveal the impact of applying a teaching course in
gaining and preserving information by female students comparing with the
traditional method, through testing the two following hypotheses:
1. There is no difference with statistical significance at the level of
significance (0.05) between the average grades achieved by the
experimental group of female students taught using a teaching course,
and the control group of female students taught using the traditional
method.
2. There is no difference with statistical significance at the level of
significance (0.05) between the average grades achieved by the
experimental group of female students taught using a teaching course,
and the contro
المستخلص
يهدف هذا البحث إلى تصميم ومكننة نظام متطور لتقويم جودة العملية التعليمية للجامعات العراقية، باعتماد مدخل الجودة، ومكننة نظام معلومات قادر على توفير البيانات بالخصائص المطلوبة التي يمكن الاستناد إليه في اجراء عملية التقويم على وفق النظام المقترح.
اعتمد البحث على أسلوبيّ دراسة الحالة والدراسة التطبيقية، للوصول إلى النتائج ا
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The literary aspect of any text reveals when it used The inspiration language
which reveals the creative aspect of language for the creator (writer) he in turn
will seek for the best choice from these aspects then, he will distribute them due
to their intention, and according to the their context
Thus, propagandistic text contains many moral features which the language
accord to thus , we found that the morning (dua al asbah)is full of creative
literary manifestations through many abstentions which happened in different
structures that contain the text, especially in structure of metaphor, and contrast.
we found many outstanding gaps and abstentions in these are given life, matter
that gives the text the most l
ريل لسادة الكيسياء َ جؼ البحث الى التعخؼ عمى أثخ استخاتيجية فجػة السعمػمات في التح َى جؼ البحث فقج صيغت الفخضية التي َ تػسط , والتحقق مغ ى ُ جى شلاب الرف الثاني الس َ ل جؼ البحث أعتسج الباحث َ تتعمق بالتحريل ولتحقيق ى ػعتيغ متداويتيغ ُ بي لسجس ِ ي السشيج التجخ ريل الجراسي , تكػنت عيشة البحث مغ َ ) شالب مغ شلاب ٗٛ( ذواتي اختبار بعجي لمتح -ٕٕٕٓالرف الثاني الستػسط في ( متػسصة الذييج خزيخ جاسع العارضي ) لمعاـ الجارسي (
... Show Moreيهدف البحث الحالي التعرف على اسناتيجية هرم الافضلية في تحصيل طلاب الصف الثاني المتةسط لمادة الكيمياء ولتحقيق هدف البحث تم اتباع الننهج شبه التجريبي ذو الضبط الجزئي وتم تحديد مجتمع البحث بطلاب الصف الثاني في جميع المدارس المتوسطة والثانوية التابعة لمديرية تربية بابل قسم تربية المسيب
This research deals with study and analyze the industrial buyer behavior and identified its objectives by determine the nature of selection the members of the purchases committees and determine the role of the purchases committees to provide requirements of the educational and scientific process and knowledge Impact of the factors ( environmental , organizational , social , and individual ) and positions of the purchase in the behavior of the members of the purchases committees and starts the importance of research in it helps university administrations in the correct choice for the members of the purchases committees and gives a picture of professional conduct professional who is supposed to b
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Use the accounting system of responsibility in assessing the performance of the company profit centers of the leather industry Given the importance of the profit centers of the General Company for Leather Industries, where a circle of activity that is accountable responsible for them (the director) about what is happening with costs and achieve revenues other words, the profit center is the beginning of an independent company with revenues and costs contribute to achieving the objectives of the company as a whole, which is to achieve profits, which means the comprehensive work of the centers of the need to evaluate its performance permanent depending on the conversion rates of the Interior. It was relied on the company's production
... Show MoreIn the subject area (participation and tandem), the study showed the views of Mr. Sadr in this field when researching first: the issue of the necessity of these two phenomena in the language that some imams of the language and principles called for to discuss and respond to, and
The research aims to study and assess the effectiveness of preventive measures banking for the reduction of money laundering based on the checklist (Check list), which have been prepared based on the paragraphs of some of the principles and recommendations of international and Money Laundering Act No. 93 of 2004 and the instructions thereto, to examine and assess the application of these measures by Gulf Commercial Bank, which was chosen to perform the search.
I've been a statement the concept of money laundering in terms of the definition and characteristics, stages and effects of political, economic and social as well as the nature of banking supervision in terms of the definition and the most important
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