Background: Thermocycling simulates the temperature dynamics in the oral environment. This in vitro study done to measure and compare the effect of thermocycling on the shear bond strength of stainless steel and sapphire brackets bonded to human enamel teeth using light cured orthodontic adhesive and debonded at various time, and to measure adhesive remnant index after debonding. Materials and Methods: one-hundred-twenty extracted upper first premolars for orthodontic reason were used in this study; depending on weather thermocycled or not, the sample was divided into two main groups, then within each group 30 teeth were used for stainless-steel brackets (Bionic®) and for sapphire brackets (Pure®). Both groups were subdivided into three groups (n = 10) according to the debond times: I: debond after 24 hour, II: debond after 7 days and III: debond after 30 days. Within 24 hr, half of the sample was thermocycled manually for 500 complete cycles between 5/55°C and the remaining sample was stored in distilled water at room temperature and water was changed daily until debond time for each group was performed. The adhesive remnant index was tested under 20X magnification lens using stereomicroscope. Results and Conclusions: Both bracket types demonstrated high shear bond strength values before thermocycling (P?0.05), whereas after 500 thermocycles, there were significant changes in shear bond strength resulted in marked reduction in the stainless steel brackets than in the sapphire brackets (P?0.05). Shear bond strength values increased with time for both stainless steel and sapphire brackets with and without thermocycling (P?0.05). The tendency of bond failure was increased at the bracket/adhesive interface rather than enamel/bracket interface in the stainless steel brackets whereas at the enamel/bracket interface rather than bracket/adhesive interface in the sapphire brackets.
The modern stylistic lesson has become more committed to the scientific limits in which it believed, and more confident in itself, and it is no longer just a scientific procedure that helps other curricula and sciences that preceded it.
Based on this, our modest research ((a stylistic vision of the objection in the Quranic discourse)) arose to explore an artistic rhetorical phenomenon that was included in the Holy Quran text. ; Because analysis is a situation that allows us to see a lot and absorb the stranger more clearly.
And since the horizontal arrangement of the linguistic elements in which stylistically undistinguished elements meet with distinct ones, the other trend has emerged that believes that the stylistic dis
... Show MoreGlorify and Praise be to God, and prayers and peace be upon the Messenger of God, his family, companions, and those who are loyal to him.
The subject derives its significance from two important sources , the first one lies in the Sunnah of the Prophet, while the other is the family source , which enrich this subject with great importance.
As for the objective of the topic, it shows to the reader the prophetic bases that mitigate and ease the burden of the husband in a way that secures the marital happiness, so that the Muslim woman takes it as a path for her in life and a slogan that illuminates the darkness of the path and makes her to overcom
... Show Moreلم تولد الجماهيرية العالية للسينما من فراغ، إنّما تحققت من إيمان المتلقي العميق، بأن الفيلم أبعد من محاولة للترفيه، فالسينما هي فلسفة العصر، التي تتناول القضايا المهمة لتقدمها عبر حكايتها مؤطّرة بمنطق محدّد ومدفوعة ببناء عاطفي مؤثر، يهيئ المتلقي للاهتمام بهذه القضايا واستيعابها، والتغير المناخي واحد من أهم المواضيع التي بدأت السينما في الحقبة السابقة بتبنيها وتقديمها ضمن بنى حكائية تزيد من وعي المتل
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Time crosses one of the most important principles that are agreed upon in contracts, because the temporal dimension has a significant impact on all contract provisions and is not limited to a certain group of them. French and Arab legal jurists alike called for this dimension to be given special attention. That is the term of the contract term; To try to limit the temporal elements, clarify their provisions and distinguish between them, but in the Arab world it did not receive the same attention that it received in the West.
Before introducing an accurate description of the publication of news about the Iraqi-British war in the press of the Great Iraqi revolution, it is necessary to note the importance of this research as it examines a remarkable phenomenon that lies at the heart of public attention at this particular time, where we live the repercussions of a new war similar, with some of its facts and activities, to the events of the Great Iraqi Revolution that broke out in many Iraqi cities. Therefore, the results of this research can be a starting point for new research characterization of the phenomenon of news coverage of war in the Iraqi press.
The importance of research in the press of the Great Iraqi Revolution, according to the well-known r
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This research discusses the developmental role of the social worker in providing care for children at risk. The research is desicriptive in nature include both the theoretical and field aspects. The theoretical aspect focuses on the characteristics and requirements of these children and what forms and implications are exposed to them by society, what is the developmental role of the social worker in the rehabilitation of this group. As for the field aspect, the study sample took a (40) social workers who working in Aiwa institutions inside Baghdad. A questionnaire of (14) questions was used as tool to collect the needed data.
Nineteenth century Gothic literature was deeply concerned with the threats against masculinity. Perhaps one of the most important changes that happened at that time was the emergence of the New Woman model which posed a great threat against masculinity and the male role in the Victorian society. Bram Stoker’s Dracula (1897) portrays female characters who embody this transition in female roles from the domestic wife to the New Woman. This paper focuses on the female characters Mina Murray and Lucy Westenra, their roles in their society, and the different fates they face at the end of the novel, with special focus on Mina’s transformation to the model of the New Woman.
The concept of Justice in the Ancient western political thought The title of research is the concept of Justice in the ancient western political heritage. It includes the definition of the idea of Justice as well as its evolution and relation to the Law the study discussed two main period . the first one was regarding the concept of Justice in the Greek political thought ( sophists ,Socrates , plato , Aristotle ,Epicureans , and stoics ) . While the second ocused on the concept of justice in Roman political thought Via their great thinkers as polypus and Cicero .
Nathaniel Hawthorne is famous for his psychological and moral themes. He is also famous for using symbolism in presenting his poignant themes of sin and its consequences. This research paper studies the use of symbols in Hawthorne's The House of Seven gables as an example of his general use of symbolism in his novels. The general pattern of Hawthorne's symbolism is that he presents one major symbol that embodies the main idea, and supports it with a number of minor symbols that develop and elucidate it. In The House of the Seven Gables, the major symbol is the house itself, which stands for corruption, evil, and the injustice of the past. This symbol is supported by such secondary symbols as the heart, the fountain, the
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