Background: Crown preparation of vital teeth involve the removal of a sound tooth structure, and when enamel removed this lead to exposed dentin with an increase in the number of open dentinal tubules also the diameter of dentinal tubules will increase, furthermore lead to increase movement of fluids inside the tubules all that causes post preparation sensitivity. The aim of this study is to evaluate the effect of desensitizing by Er:Cr:YSGG laser on shear bond strength of prepared tooth and resin cement. Materials and methods: Thirty sound maxillary premolars, grouped into three groups(n=10). Group A is the control group, group B irradiated by Er:Cr:YSGG laser with (0.25 W, 20 Hz, 10%water and air), group C irradiated by Er:Cr:YSGG laser with (0.5 W, 20 Hz, 10% water and air). Results: SEM examination showed complete occlusion of opened dentinal tubules after laser irradiation of both groups that irradiated with laser. Statistical analysis showed significant increase in surface roughness in group B and C. SBS was significantly increase in group B with no significant increase in group C. Conclusion: Er:Cr:YSGG laser can occlude open dentinal tubules without and adverse effect on the retention of the restoration, on the contrary it increase bonding strength. And this increasing was significant in group B with (0.25W, 20 Hz, 10 % water and air). suggestion: so the parameters used in group B (0.25 W, 20Hz, 10 % water and air) is recommended for desensitizing prepared tooth and induce enhancement to the bonding strength of resin to tooth surface.
استهدف البحث الكشف عن المكانة الاجتماعية لطفل الروضة بين أقرانه ، ودلالة الفروق في المكانة الاجتماعية لاطفال عينة البحث التي تعزي الى بعض المتغيرات من خلال الاجابة عن الاسئلة الاتية :
اولاً : ما المكانة الاجتماعية لدى اطفال الروضة بين اقرانهم ؟
ثانياً : ما علاقة المكانة الاجتماعية لدى اطفال الروضة ببعض المتغيرات و ذلك من خلال اختبار الفرضيات الصفرية الآتية :
The Character is one of the elements of Storytelling, as it is the center of the plot, making it the basis on which the talk is about. The talk is the portrayal of the character while they’re acting; the novelist presents the character by interacting with the events, and the extent of the negative and positive appearing impact on the character. It should be noted that everyone has two personalities or more, each one appearing in a different position or situation. For instance, a man can be a father, a lover, an employee, a son or anyone else .. in another position, he might be a master, and in another a looser begging for the mercy of his humiliator, and sometimes he can show weakness to the one he loves, or show strength to his enemie
... Show MoreThis study aimed to analyze and measure the relationship between oil revenues and financial sustainability in Iraq, the study used the stylistic approach inductive and deductive approach. Accompanied by the use of quantitative and analytical style, which was based on two variables oil revenues and net general budget on annual data covered the period (1990-2013). Among the most important findings of the study contain the time-series variables study on the root of the unit and is not stable in the general level, and become stable after the use of mathematical processors to gain access to a stable by taking the first difference of natural Ogartm of the series. The way (Johnson) to a long-term relationship between oil revenues and ne
... Show Moreمعيار 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
وهذا البحث ناقش مفهوم(القصديَّة) لغةً ،واصطلاحاً . فاللغة والكلام شكل من أشكال الوجود الإنساني و( الكلام) هو وسيلة التواصل بين الملقي القارئ ، والمتلقي السامع ؛ وللتوصل الى الدلالة القصديَّة الدقيقة للغة المنطوقة وا
... Show MoreEl sumario
“la lluvia amarilla” en una novela española que es una obra biográfica de un Aldeano hombre muerte, Andrés, quien niega abandonar su pueblo, Ainielle, y después la muerte de su esposa, la vida estaba difícil y las memorias comenzaron a perseguirlo, sus Los familiares de los fallecidos comenzaron a venir en su imaginación y sentarse delante de la chimenea y le llame a ir con ellos.
Nuestra novela del autor Julio Llamazares es llena de figuras retoricas y para dar un profundo visión de las metáforas principales que son (la lluvia, el color amarillo y la soga) realizamos un estudio analítico con el Corán sagrado y hemos visto los riesgos de las diferencias y similitudes en los
... Show MoreThis study aims to clarify the role of Iraqi satellite channels in spreading negative values among university youth; and the tendency of this segment to simulate the descending behaviors and pseudo-peculiar concepts of our society, which are displayed through the screens of these channels, based on the relevant media literature such as scientific references and the results of previous studies and research.
The study followed the survey methodology to examine the public based on the questionnaire as a research tool, which was distributed to a sample of male and female students of Baghdad University enrolled in the university for the academic year 2011-2012.
In order to achieve the specific objectives of this research
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Abstract
Oil is the most important natural resources in Iraq and represents the goal to others as well as Iraqi people. It is gift from God to all Iraqi people now and future. So we must maintain it and invest its revenue that achieve development in country and ensure the next generations' rights in it without external costs or negative externalities from extracted and invested it.
The most problems that we attempt to solve by this research are the exhausted, environmental degradation and theft from next generation that produced with oil contracts between Iraq and foreign companies. From here was th
... Show Moreاهتمت المجتمعات العالمية في الآونة الأخير بفئة الأطفال ، ورعاية الطفولة وذلك لما لها من أهمية كبيرة في مستقبل المجتمع ، وتنميتة وتقدمه . لأنها يعتمد عليها في تقدم وتطور المجتمع فـي جميع المجالات الاقتصادية والاجتماعية والثقافية . ومن هنا ارتبطت الطفولة بالحياة برباط عضوي فالأطفال براعم الحياة ومع هذه البراعم تستمر الحياة لذلك اهتمت دول العالم بوضع البرامج وعقد المؤتمرات من اجل النهوض
... Show MorePurpose This study was design to investigate of Purpose This study was design to investigate of P. aeruginosa, an example of Gram-negative bacteria, in seven primary and secondary schools of Baghdad city, and the effects of Ethanol and Dettol of P. aeruginosa biofilm. Design/methodology/approach Seventy swabs were collected from seven primary and secondary schools of Baghdad city, Iraq, during November -December 2022. Swabs were collected from classes desk, doors handles, students hands and water taps. Standard microbiological testing methods were used on the samples for isolation and identification. The ability of bacteria to form biofilm and the effects of Ethanol and Dettol on “preformed” biofilms was examined by microtiter plate wi
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