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 current study aimed to know the reasons for the reluctance of
students to apply mathematics department in the Iraqi
universities. In order to achieve the objective of the study the
researchers a tool numbers of 4 - axes included 40 - paragraph,
distributed as follows:
- Set the first axis causes that relate to the student, the 14
paragraph.
- The second axis includes clauses concerning teacher and the
number of paragraphs of Article 9, paragraph.
- Axis III contains clauses concerning the nature of mathematics
and a number of paragraphs 11 paragraphs.
- The fourth, which included reasons related to classmates and
close and the number of paragraphs 6, paragraph.
The resolution offered on a group
That the Jewish minority in Iraq, were considered among the Iraqi people, building.
The research includes a bout IL- IQulle , and their role in scientific of the Islamic – Arabic civilization , for Dr. Khlood M.Namma the proff in the collage of education for woman , Baghdad university , History department .
In the light of the globalization Which surrounds the business environment and whose impact has been reflected on industrial economic units the whole world has become a single market that affects its variables on all units and is affected by the economic contribution of each economic unit as much as its share. The problem of this research is that the use of Pareto analysis enables industrial economic units to diagnose the risks surrounding them , so the main objective of the research was to classify risks into both internal and external types and identify any risks that require more attention.
The research was based on the hypothesis that Pareto analysis used, risks can be identified and addressed before they occur.
... Show Moreهدفت الدراسة التعرف على الشفقة بالذات لدى الطلبة فضلا عن التعرف على الفروق في الشفقة بالذات وفق متغيرات : الجنس –التخصص الدراسي – المرحلة الدراسية، تالفت عينة الدراسة من (200) طالب وطالبة موزعين بالتساوي حسب الجنس (ذكور – اناث) والتخصص الدراسي (علمي - انساني) والمرحلة الدراسية ( الاولى - الرابعة )، وبعد تطبيق مقياس الدراسة وتحليل الاجابات احصائيا ، اظهرت النتائج ان الطلبة لديهم شفقة بالذات كما اظهرت النتائج عدم
... Show MoreThe research included the statement of some prophetic
guidelines for preserving food and drink from contamination that
causes diseases, which originate either viruses and microbes, or
insects and vermin spread in the air,
The science of exegesis was started by the first teacher, the Holy Prophet, and then further developed in various methods and approaches through history
Despite the principle of separation of powers brought by the French Revolution, which entrusted the task of drafting legislation and its amendment to the legislative authority and the task of settling disputes and settling them in the judiciary. However, since that date, the French judiciary has played a major role in the development of French civil law (In spite of all the economic and social developments that have taken place in French society throughout these years) since its promulgation until February of 2016, the date of the Legislative Decree No. 131 of the year 2016 A modification is the largest in the history of the French Civil Code (which was the judicial precedents in which a significant impact), was assisted by the French judic
... Show MoreAbstract
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
... Show MoreThe nation-building process in fragile states is complex, often involving multifaceted challenges and opportunities. A pertinent example is Iraq post-2003, which serves as a model to study the intricacies of rebuilding a nation in the aftermath of conflict. During this period, we witnessed a significant international intervention aimed at establishing democratic governance, fostering economic development, and restoring social stability. Iraq’s nation-building journey showcases both successes and shortcomings. Establishing a representative government marked a step towards inclusivity and political participation, yet sectarian tensions persisted, hindering cohesive national identity. Economic initiatives aimed to harness Iraq's oil resou
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