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.
معيار القصديَّة في النص هو من الدراسات الحديثة المتطورة من لسانيات الجملة الى لسانيات النص ، وتحليل الخطاب . والذي يعنى بالطرق والأدوات التي يستغلها المؤلف لتحقيق الغايات المقصديَّة
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Find aimed to reveal the teaching practices of the teaching faculties of education departments of the University of Baghdad in the light of the motives of learning from the perspective of students . Researcher selected the research community in a deliberate humanitarian sections of students and faculties of education for girls and IbnRushd . Ed reached basic research sample ( 400 ) students were numbers search tool questionnaire , and included (30) paragraph . In processors statistical data , use the weighted average and the weight percentile , results have shown that it is more paragraphs which received wide acceptance from the viewpoint of students ( do not make fun of the students' answers wrong but corrects and discussed with them )
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running the requirement color important place in object of life activity both public and private, Fallon makes represents energy expressive and aesthetic in designing furniture street, especially (positions waiting buses passenger transport)which took looms large in attention receiver designer also, through civilized development and urban and change the city. Requirement, The positions of waiting progress jobs service and that would interact to produces Photos aesthetic Furniture for space street and understand receiver, affect the operation his life and the development of his environment and his psyche and culture of because they entity variable and sophisticated, impose on us to find foundations a design and conditions of chromatic esp
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التسليات في البلدان الاسلامية مشاهد حياة الطرب والالات الموسيقية كما يعكسها الفن
Since the early ages, scientists have been keen on the second source of Islamic law, namely the hadith of the Prophet. They also took from the less disciplined narrators, but they chose from their conversations a selection, and for this some prominent narrators who can be considered that Ibn Habban has been hardened to weaken them. Narrators who avoided Ibn Habban novel They are not true because Ibn Habban neglected her and left her to hurt some narrators who are confident in themselves
The follower of the art of Arabic calligraphy accurately identifies three prominent dimensions that have framed the dimensions of this art, the functional dimension and the aesthetic dimension, the last of which is the expressive dimension, as it is an art that does not exhaust its aesthetic and indicative purposes because of its possibilities and characteristics that help it to form with any entity designed by calligrapher, with the expressive dimension of the most important of those The dimensions that can be studied within multiple variables, the most important of which are the significance of the text, the spatial and formal organization of the calligraphic functions and the power of the idea from which the calligraphic formation eme
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