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.
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
this research talks about the weakness that had happened in the construction of the sentences which effected on the syntactic meaning . it considers an important problems faced the languages .
المنازعات والحروب الاهلية في العالم الثالث نموذجاً الصومال وافغانستان
تناول البحث أبعاد الذكاءات المتعددة كمتغير مستقل بأبعاده الفرعية الثمانية ( الذكاء الاجتماعي ،الذكاء الطبيعي، الذكاء البصري، الذكاء المنطقي، الذكاء اللغوي، الذكاء الموسيقي، الذكاء الحركي/الحسي، الذكاء الشخصي/ البيئي) واليقظة الاستراتيجية كمتغير تابع بأبعاده الفرعية الثلاثة ( اليقظة التجارية، اليقظة التنافسية ، اليقظة التكنولوجية) وقد تم اختيار عينة من المديرين العاملين في وزارة الصناعة والمعادن، فق
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ان الداسات القرانية تعد من الدراسات المتعلقة في اللغة العربية لانها تتعلق بدراسة جانب من جوانب اعجاز القرأن الكريم لذلك قمت بدراسة جانب من جوانب اعجاز القران الا وهي لفظة اكل
ان الهدف من البحث هو تقويم منهاج الفيزياء للصف الاول الثانوي في الجمهورية اليمنية
Advantage of the science of management for a lot of other sciences vitality and openness to the rest of the science and knowledge of the various branches fields, and at the same time, overlapping and intermingling majora between the various branches of administration and specialties, and based on this fact, the idea of this research to come out of one of the important topics with two topics of vital in the field of strategic management, namely patterns Strategic Command, and the effectiveness of senior management teams. I've seen the science of management, particularly in the field of strategic management, large shifts and changes, especially in the last two decades, as the RPR Strategic Management rich field of research and the emergenc
... 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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