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.
The organization and development of the irrigation system and agrarian reform in Iraq had an impact on the diversity of its methods and uses.
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 MoreTargeted research to study variations formalism in the paintings of the scratch -linear , and through surveys carried out by the researcher , found and to his knowledge that the study did not address the researchers before, this researcher found rationale in the study of plates scratch and identify variations of design in it. , Which included the first chapter of the research problem in question the following: What morphological variations in the paintings of the scratch -linear ?In order to reach solutions to this problem and to achieve results so research aims to identify the characteristics of the scratch for paintings , and design fundamentals and relationships , which are identified by the researcher Balentajat completed in all of I
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يتناول 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 .
This research involves the civilized vision of the trends and approaches of philosophical thought in the Islamic Orient, whose objectives were to show Islamic philosophy and the pioneers of thought in it and the most important products that crystallized after its emergence in the Islamic world
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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