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.
تهدف هذه الد ا رسة الى التعرف على السلوك التصويتي للمقترعات الع ا رقيات. والأسباب التي تدفعهن للمشاركة في عملية الاقت ا رع، والعوامل المؤثرة في خيا ا رتهن التصويتية والأسباب التي تجعلها تفضل اختيار الرجل أو اختيار ام أ ر ة ، وأخي ا رً مدى م ا رعاة اج ا رءات الاقت ا رع لظروف النساء واحتياجاتهن واهتماماتهن. اعتم دتالد ا رسة منهجاً وصفياً واستعان ت بطريقة المسح بالعينةاما الاداة الرئيسية فهي الاستمارة الاستبيانية.
... Show Moreبينت النظريات والمناهج النقدية الحديثة بعد تفعيلها لوسائل قراءة النص وتحليل عناصره وبيان وسائل تماسكه وروابطه فضلا عن تمثيله لمضامين مركزية ودلالات فرعية ان النصوص التراثية بوصفها نصوصا كاملة لسمات النص المؤثر قابلة للحضور في مجال المعرفة وفق تصور حديث يختلف عن تصور منتجهامنهجيا كما اتضح مدى عمق هذه النظريات والاسس التي ارساها بلاغيو العرب التي كانت ولاتزال محط انظار كبار النقاد وباحثي البلاغة.
הקדמה
המילה היא יחידה בסיסית ב שפה המתאפיינת בכך שיש לה משמעות ייחודית וביטוי פונטי )בשפה מדוברת (, גרפי
)בכתיבה( או מרחבי )בשפת סימנים. ובעיקר המונח מילה מתייחס ל שפות טבעיות או לשפות מתוכננות , אבל הוא קיים
גם בשפות מלאכותיות כגון שפות תכנות או שפות לוגיקה . בית היא מהמילות שראינו צריך לחקור אותה מתוך
משמצאנו בה מתפקידים גדולים בפעולה חשובה בתולדות הלשון עהברית שהיא התחדיש, פעולה זו שנכנסה לעברית אחרי
اسباب تفرد استخدام خط النسخ في تصميم الحروف الطباعية
في تعزيز بيئة الانتاج الرشيق استخدام اسلوب S -5
That the Jewish minority in Iraq, were considered among the Iraqi people, building.
In the light of the globalization Which surrounds the business environment and whose impact has been reflected on industrial economic units the whole world has become a single market that affects its variables on all units and is affected by the economic contribution of each economic unit as much as its share. The problem of this research is that the use of Pareto analysis enables industrial economic units to diagnose the risks surrounding them , so the main objective of the research was to classify risks into both internal and external types and identify any risks that require more attention.
The research was based on the hypothesis that Pareto analysis used, risks can be identified and addressed before they occur.
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هدفت الدراسة التعرف على الشفقة بالذات لدى الطلبة فضلا عن التعرف على الفروق في الشفقة بالذات وفق متغيرات : الجنس –التخصص الدراسي – المرحلة الدراسية، تالفت عينة الدراسة من (200) طالب وطالبة موزعين بالتساوي حسب الجنس (ذكور – اناث) والتخصص الدراسي (علمي - انساني) والمرحلة الدراسية ( الاولى - الرابعة )، وبعد تطبيق مقياس الدراسة وتحليل الاجابات احصائيا ، اظهرت النتائج ان الطلبة لديهم شفقة بالذات كما اظهرت النتائج عدم
... Show MoreThe research included the statement of some prophetic
guidelines for preserving food and drink from contamination that
causes diseases, which originate either viruses and microbes, or
insects and vermin spread in the air,
The science of exegesis was started by the first teacher, the Holy Prophet, and then further developed in various methods and approaches through history