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.
Abstract
This research aims to determine the nature of tacit knowledge relationship and its impact on building the electronic human resources management, as it constitutes the most prominent tacit knowledge resources owned by the Organization for being a stand out in the skill, knowledge and intellectual capacity of human resources, as the electronic human resources management is a contemporary trend that adopted by the organization in the performance of all tasks and duties related workers have remained in the contemporary environment in which it operates.
and have indicated the research problem to the low level of awareness of the ad
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The Qur'an was revealed with a clear Arabic tongue, and it seized minds, and was astonished by its eloquence and eloquence of tastes, so it was a new dawn, and a nucleus for the birth of a new literature inspired by the tolerant thought of Islam, its fresh words, and its delicate and revealing meanings
The holy city of Najaf is a vital space that helps to bring people together within a particular context, thus strengthening intellectual communication, community participation and increasing opportunities to learn about different cultures
برزت الشخصانية في حقبة تاريخية كان فيها العالم و اوربا وفرنسا تشهد انتهاء حقبة حضارية امتدت من نهاية القرون الوسطى حتى اوائل القرن العشرين تميزت بكونها رأسمالية التركيب، ليبرالية المنهج، وبرجوازية القيم، جاءت الشخصانية ليس فقط محاولة للإجابة عن حقبة جديدة ولادة حضارة جديدة لاتزال غامضة المعالم فحسب انما ايضا كرد على المدرسة الماركسية المادية والوجودية الملحدة محددة هدفها الابعد بإعادة صنع النهضة
The Holy Koran is the highest text in the eloquence, It is one of the
important sources of the linguistic syntactic and eloquent study; it impacts
upon these sciences Avery intense impact through advancing its verses as an
argument in the confirmation of the significance of the term
The holy Koran was and still the fountain of the linguistic studies, as
they tend towards it since the second century of the hegira. So this research is
a study of the expressive terms concerning the rain in the holly Koran, a
linguistic study; it aims to study the term concerning its linguistic and
conjugate significance and its expression concerning the rain through reality
and metaphor.
The fashion accused important optical avenge with the rest of visual elements
, That style of fashion design stir up beautiful feelings by using fashion forming
that is suitable with the nature of designable treatments to other elements .
The fashions contains the nature of relation ships of educational address and
the kind of beliefs , So the visual beauty is limited for those relation which are the
designer fashion tried to redesign and set them anew . so as to goes with beautifully
with the last visual for fashions.
يهدف البحث إلى قياس تاثير راس المال المودع للمستثمرين غير العراقيين والمستثمر في أسهم شركات المدرجة في سوق العراق للأوراق المالية في القيمة السوقية لتلك الشركات
The research aims to study and analyze the reality of the internal control system in the company surveyed . To find out how effective and efficient internal control system , problem – centered research that addressed the performance of the internal control system .
The research Description applied and the interview Alchksahvi analysis and interpretation of results . The researchers recommended the need for attention to the training courses and the need for segregation of duties and functions in the main and subsidiary records , taking in to account periodic reconciliations between the lists and financ
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