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 study of these selected traces shows that what Imam Mardini did on Imam al-Zayla'i and enabled him to graduate the hadiths of the book (guidance and conclusions) as well as in choosing the novel closest to Murad the work and not as described by al-Zayla'i .... never deserves descriptions.
This research aims to determine the importance of the role that agile leadership plays in supporting programs and areas of investment in human capital, as it is the most important type of capital that the organization possesses and achieves returns that are many times the cost it bears, due to its rare and valuable characteristics. Through six behaviours: (humility behaviour, calm behaviour, wisdom behaviour, patience behaviour, objectivity behaviour, trust behaviour). As for investment in human capital, it was measured through its four elements (skills, knowledge, capabilities, experiences). Despite this, the researched organizations suffer from a decrease in awareness of the importance of this type of investment and the role of
... Show More
In this article we study a single stochastic process model for the evaluate the assets pricing and stock.,On of the models le'vy . depending on the so –called Brownian subordinate as it has been depending on the so-called Normal Inverse Gaussian (NIG). this article aims as the estimate that the parameters of his model using my way (MME,MLE) and then employ those estimate of the parameters is the study of stock returns and evaluate asset pricing for both the united Bank and Bank of North which their data were taken from the Iraq stock Exchange.
which showed the results to a preference MLE on MME based on the standard of comparison the average square e
... Show MoreThe research aims to identify how to enhance the quality of the human resources, focusing on four dimensions (efficiency, effectiveness, flexibility, and reliability), by adopting an adventure learning method that combines theoretical and applied aspects at the same time, when developing human resources and is applied using information technology, and that Through its dimensions, which are (cooperation, interaction, communication, and understanding), as the research problem indicated a clear deficiency in the cognitive perception of the mechanism of employing adventure learning dimensions in enhancing human resources quality, so the importance of research was to present treatments and proposals to reduce this problem. To achieve
... Show Moreانصبت هذه الدراسة على قياس جودة الخدمة، وبوجه خاص ماهية أبعاد جودة الخدمة التي يجري قياسها للوصول إلى مستوى جودة الخدمة. وتم التطبيق على خدمة التعليم العالي الخاص، حيث جرى اختيار عينة من طلبة جامعة خاصة لتعبئة الاستبانة الخاصة بالدراسة. وكان هناك 360استبانة تم تحليل البيانات فيها من خلال مؤشرات الإحصاء الوصفي، وتحليل الارتباط، وتحليل الانحدار المتعدد. وقد توصلت الدراسة إلى وجود علاقة ارتباط بين مستويات
... Show MoreThe present study aimed to measure the calendar estimates for my book Physics of the preparatory phase (fourth and fifth preparatory) has been a research sample consisted of 32 teachers and a school for 36 schools from both sides of the Rusafa and Karkh first To achieve the objectives Find promised researcher tool for measuring the calendar estimates for my book Physics of the preparatory phase in accordance with the contemporary scientific innovations as formed tool from 5 innovations built on the basis of which the paragraphs which formed the final version of the 21 paragraph manual are not substitutes to answer yes -No Your has been used Baha percentages to reach the results may reach current research conclusion which is defic
... Show MoreIt is doubtless that the sexual place has some common indicators due to the masculine and feminine bodies which may be natural or deviated (homosexual). The female has an act of voice in the imaginary masculine place whereas the male has an act of image recognized in the parental mind in both the secular and sacred place. Those places create different limits and perceptions according to the auditory and visual readings in search of identity, text and body in the feminine dramatic text.
The research includes four chapters; the first, the methodological framework, involves the problem which is centralized in the following enquiry: What is the relationship between the place and the term of
... Show More