Background: Radiopacity is one of the prerequisites for dental materials, especially for composite restorations. It's essential for easy detection of secondary dental caries as well as observation of the radiographic interface between the materials and tooth structure. The aim of this study to assess the difference in radiopacity of different resin composites using a digital x-ray system. Materials and methods: Ten specimens (6mm diameter and 1mm thickness) of three types of composite resins (Evetric, Estelite Sigma Quick,and G-aenial) were fabricated using Teflon mold. The radiopacity was assessed using dental radiography equipment in combination with a phosphor plate digital system and a grey scale value aluminum step wedge with thickness varying from 1mm to 10mm in steps of 1mm each. The tested materials were radiographed, we used Image J software, on a computer screen to evaluate the degree of radiopacity for each individual material and compare with the aluminum step wedge. Radiopacity was expressed in mm of equivalent aluminum step wedge. Analysis of varience (ANOVA) and Least Significant Difference (LSD) were used to investigate the significance of differences among the tested groups. Results: Statistical analysis showed highly significant difference among the tested groups (p≤0.01). Amongst, G-aenial composite shows the most radiopaque and it is above or equivalent to that of enamel, while Estelite Sigma Quick composite has the lowest radiopacity value and is equivalent to that of dentin. Conclusion: In line with previous studies, and within the limitation of our study, considerable variations in radiopacity values were found among materials depending on the radiopaque elements incorporated into the matrix. All composite materials tested complied with the ISO 4049 standard.
the first part of the research involves investigate the aspect of the radiation superposed on the one bright soliton pulse propagated on ideal single mode
Abu Firas al- Hamdani is one of the most prominent abbasid poets Who characterized their poetry with high artistic quality especially in his Romyate which blended the quality of feelings of grief, sorrow, longing and nostalgia that makes sensitive self conflict that stems with time from one hand and with place on the other hand. Because we are dealing with a poet lived west spatial coercive which it has been hurt him within a time conflict swinging between despair and some times patience and hope other times between the present and his painful reality also between the past and the beautiful times.
This researcher is to stand on this Romyat by monitoring effectiveness of the poetic text based on conflict between the presenc
The investment however "was its description and meaning, it remains a resident" in the composition of capital assets located in the forefront of the creation of productive assets, and this means that the investment in the productive sectors is a priority in achieving capital accumulation, on any other investment that takes place with the stages of advanced development of formation , not forgetting "to humans and investment humans as head of real money product, the source of the economic surplus and accumulation, and the source of producing values, and if human labor was the source of value, and the human was the source of work, therefore humanitarian work on different levels and skills presents capital", so the investment in huma
... Show MoreSports risk has become a threat to the sports sector in general and the impact on an efficient player and the old stadiums in particular. So have such a thing fertile ground of global insurance companies to exploit it optimally exploited through the development and marketing of insurance lids for the provision of protection for athletes of different risks they may face, which contributed to the growth and development of the performance of these companies and helped in the emergence of sports insurance specialist firms. And through the insurance process in the field of sports and where the insurance is a type of social solidarity. The main problem is this spirit manifested search in question is whether to embrace sports institutions sport
... Show MoreThe industrial production sector has an important role in the national economy of the advanced countries as well as the developing ones to get higher levels for their economy . We in Iraq , just like most of the develpoing countries , our economy still suffers of great shortage in this active sector in spite of the repeated statements about the desire of activating the contribution of this sector in the national economy . The industrial sector in Iraq suffers in general of many problems , especially the public industrial sector (manufacturing) . These problems have been existed because of the unnatural conditions that Iraq has passed during the previous decades especially in the political and security sides . which reflecte
... Show MoreThe research aims to measure the impact of the empowerment strategy on the performance of employees by mediating organizational trust in the organization. The problem of research was the weak ability of most business organizations to employ the strategy of empowerment in maximizing the performance of employees, and the importance of research in practice lies in the results of a guide to managers in how to use the strategy of empowerment in maximizing the performance of employees by mediating organizational trust dimensions of ability, benevolence, integrity. In order to achieve the objectives of the research and to answer the questions of the problem, the researcher has adopted the descriptive analytical approach as the questionnaire was
... Show MoreHaruki Murakami (1949-present) is a contemporary Japanese writer whose works have been translated into fifty languages and won him plenty of Japanese and international awards. His short stories are well constructed in a weird realistic manner and are mixed with elements of surrealism. His novels and short stories fall under the genre of magical realism. One of the major revolving themes that Murakami wrote about was the haunting feeling of emptiness and disconnectedness in a world which seems to care much for materialism and self-interests.
The paper explores two of Murakami’s short stories in his book After the Quake (2000) and the relevance of their themes and characters to Iraq after the q
... Show MoreComplexity is the inherent characteristic of contemporary organizations. It is characterized by the intertwining and expansion of its relations, by the severe disorder and rapid change in its environment, which makes it suffer from a state of uncertainty in determining the direction of its future or the assessment of the rules governing its paths. All organizations tend to evolve with increasing sophistication, And to take measures that contribute to the simplification of the system as it moves towards complexity, allowing the administration to easily control its movement and directions, and the problem of complexity in the university is based on the entanglement and overlap in the goals and processes betwe
... Show MoreThe paper aims to identify the impact of discrete realization strategy in the development of reflective thinking among students: (males/females) of Qur'an and Islamic education departments for the course of Islamic jurisprudence according to the variability of sex. The researcher used the experimental approach and adopted an experimental determination with a set part of the two groups (experimental and controlled). He selected the sample deliberately which consists of (147) students spread over four classes (experimental males/ experimental females/ controlled males/ controlled females), and it took last for an academic year of (2010-2011). He, then, prepared a post test to measure the reflective thinking with his five skills (skill of o
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