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 Islamic Issue did not rise the “widespread arguments” in contemporary times, just as the issue of applying Islamic Law. Just as the Islamic forces used this purpose, or employed it during their march to reach to power by adopting the sacred as motivation towered the power, or control the governance. However, the reality show that this goal remained within the boundaries of slogans in the sense of a teleological slogan, and did not go beyond the limits of advocacy or arrangement as the primary source of legislation with differences of teleological reasoning, in a manner that reflected an intellectual problem about the validity of the use of this concept or the ability to apply and enforce the law in today's world, to impose
... Show MoreMany studies have recommended implying the skills and strategies of creative thinking, critical thinking, and reflective thinking in EFLT curriculum to overcome EFL teaching-learning process difficulties. It is really necessary to make EFL teachers aware of the importance of cultural thinking and have a high perception of its forces. Culture of thinking consists of eight cultural forces in every learning situation; it helps to shape the group's cultural dynamic. These forces are expectations, language, time, modeling, opportunities, routines, interactions, and environment. This study aims to investigate EFL student-teachers’ perceptions of cultural thinking. The participants are selected randomly from the fourth-stage students at
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We produced a study in Estimation for Reliability of the Exponential distribution based on the Bayesian approach. These estimates are derived using Bayesian approaches. In the Bayesian approach, the parameter of the Exponential distribution is assumed to be random variable .we derived bayes estimators of reliability under four types when the prior distribution for the scale parameter of the Exponential distribution is: Inverse Chi-squar
... Show MoreHuman values are the most important concepts that the interest of society has to relay on these conceptual values. Any society will not be stabilized unless adheres to the right principles and values, all nations need such principles and values to stabilize. If any society doesn’t implement the human values that monotheistic religions urges equality between human, the far the society from the religious principles, the less there would be valence between human. The valence is urgent necessity in the current time. The far people get away from values and principles, the more they lose their freedom and dignity, therefore individual has to live with dignity and respect through the adherence to these values and principles. Apparently, equal
... Show MoreThe inflammatory bowel disease (IBD), Crohn’s disease (CD) and ulcerative colitis (UC) are heterogenous chronic inflammatory disorders of the gastrointestinal tract. The most widely accepted etiopathogenic hypothesis for these disorders suggests an immune mediated process.
Objective: This study was performed to evaluate the role of interleukine-33 in pathogenesis of inflammatory bowel disease and to correlate their levels with the disease activity and/or severity.
Methods: Fifty five subjects with inflammatory bowel disease (41 ulcerative colitis patients and 14 Crohn’s disease patients) their ages range from 16-65 years and 25 apparently healthy volunteers their ages and sexes were matched with the patients were participated i
Ismailism is of great importance in Islamic history and Islamic political thought. In different countries of the Muslim world today their presence exists and is active but is confused with mystery and secrecy. The most important characteristic of their political ideology is their dependence on the esoteric exegesis, which they have made an intellectual basis for which their most ideas relate, when they make for everything visible and exposed a hidden matter, not only aware of the esoteric exegesis, which only God knows and entrenched in science, and they mean imams or whoever They are called "(esoteric)" as a result of the Ismaili belief in esoteric interpretation and that everything is apparent inward, as well as they called the ((seven
... Show MoreThe research addresses smart city concept as it is the latest urban design trends, by the investment of the capabilities of human, and artificial intelligence for the sake of the advancement of the city. The concept of a smart city is described as one of the most important manifestations of the information revolution, with the end of the twentieth, and the beginning of twenty – first century, The research attributes the emergence of the concept to: deficiencies of means, and traditional methods in building and development of cities, as well as The significant increase in the number of city and global metropolises dwellers. So, smart city approach has been adopted, along with innovative principles and methods which cons
... Show MoreA total of 722 algal taxa are recorded in Diyala River by different authors. Most of the identification algae belong to three Divisions: Bacillariophyceae (367, 50.8%), Chlorophyceae (179, 24.8%), and Cyanophyceae (126, 17.5%).
The research aims to measure the impact of knowledge management processes individually and in total in the innovative marketing.
We depart search of a problem expressed in a number of intellectual and practical questions, the application of this research in the General Company for Vegetable Oil Industry, represented composed a sample of (63) (Director General and Deputy Director General and Director of the Department and the Division) in the company researched, it has been designed measuring instrument to collect the necessary data either statistical means they are the percentage and the arithmetic mean and standard deviation and coefficient of variation and the coefficient of simple correlation and model
... Show MoreSustainability is a concept embodied in traditional architecture around the world since ancient times through spontaneous experimental compatibility with the environment and efficient exploitation of the natural resources of the environment according to a rapid development of trial and error over the years . Architecture was the basic means that man devised to protect him from the harsh conditions of the external environment by exploiting natural energy sources such as the sun, wind, and soil capabilitie, Many of the principles of sustainability overlapped with the social organization and human behavior of the community as it was reflected in the urban production at the level of standards of city planning and urban agglomerations as well
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