Background: The accuracy of fitness of any dental casting is imperative for the success of any prosthodontic treatment. From the time that dental casting was first introduced, efforts have been made to produce more accurate and better fitted castings with minimal marginal discrepancy. The aim of this in vitro study was to evaluate the effects of three different investing and burnout techniques on the vertical marginal discrepancies ofceramometalcopings invested with two types of phosphate- bonded investments. Materials and methods: Sixty wax patterns were fabricated on a standardized prepared brass die representing an upper central incisor by the aid of a custom-made split mold. Three different investing and burnout techniques were applied for an Iraqi investment and a commercial type; Group I:Ring investing with conventional burnout technique (RC);Group II: Ringless investing with conventional burnout technique (RLC);Group III: Ring investing with accelerated burnout technique (RA).Twenty wax patterns of each group were divided into two subgroups according to the type of investment material used (10 for each subgroup) represented as (B) for the BellaStar XL and (W) for the WYMvest investments. Complete castings were finished and seated on the metal die. The accuracy of fit of each coping was determined by measuring the vertical marginal discrepancies between the finish line on the metal die and the margins of each coping at four specific reference points on the labial, mesial, palatal, and distal aspects of the die by the aid of a light microscope supplied with a digital camera.The arithmetic mean of each three records was computed and regarded as the amount of the marginal discrepancy of each coping and was used as a unit for the statistical analysis. Results: Mean marginal accuracy for W(RLC)was found to be the least (13.839+4.5724 um) while the highest mean value related to B(RLC) (29.033+2.102 um). In general, ANOVA test showed significant results among the mean values of the Binvestment subgroups while LSD test showed non-significance between the (RA) and both the (RC) and (RLC) subgroups. On the other hand, significance was present between the (RLC) and (RA)of the Winvestment subgroups while non-significance was located between the (RC) and both the (RLC) and (RA) subgroups. Comparing similar subgroups of the two tested investments, the Student's t-test showed non-significance between the (RC) subgroups while high significance was located between the (RLC) and (RA) subgroups respectively.Concerning the vertical marginal discrepancy of the copings, applying the (RC) technique for both investments caused non-statistical significance between the labial, mesial, palatal, and distal aspects.The (RLC) technique caused high significance between the four aspects, while the (RA) technique caused non-significance between the labial aspect only and the others. Conclusion: The Iraqi investment generally produced less vertical marginal discrepancies (using the three different investing and burn-out techniques) than the commercial investment.In order to achieve a better marginal fit, it seems that ceramometalcopings invested with the commercial investment tested are better be cast using the conventional ring investing and burnout technique.
The research talks about the concept of investment allocations, showing its linguistic and idiomatic meaning, as well as the objectives for which the investment allocations are based, as well as the benefits of these allocations since it shows types of investment contracts, including: current and fixed assets and commitment allocations.
The research has been concluded with several results, including the protection of the banks and the investor. The contracting parties focus on specific dates that both parties are obliged to abide by, the research also shows the jurisprudence provisions for investment allocations, each ruling according to the specific branch.
... Show MoreThe unbalanced distribution of investments in the economic fields of the 1950s had a negative impact on the overall economic life of the country in that period and subsequent periods. Since the 1960s, the planning agencies have tried to reduce the negative impact of imbalance in regional development and the emergence of disparities in development between the regions of the country and to identify disparities in levels of spatial development. At the planning level, there have been many studies and mathematical and statistical models to analyze variance and clarify its dimensions and to measure the degree of developmental disparity between Regions and means of narrowing this problem and the development of policies and strategies for develo
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This study examined the problematic of the ambiguous relationship between the media and terrorism and the problems that result from press coverage of terroristic incidents. The paper sought to show the classification and confrontation of such incidents had been established from the point of view of a sample of media professionals, researchers and writers who are frequenters of Al-Mutanabi Street in Baghdad. The media outlets that carry this coverage would not give up their media mission as well as the terrorists would not be given an opportunity to take advantage of this coverage in achieving their goals and objectives. Furthermore, the terrorist organizations would have no chance to exploit these means to deliver their terroristic messa
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Iraqi EFL students face difficulties in writing composition, especially academic writing, which affects negatively their exam results. This study has been conducted in the Department of English at College of Education for Women, University of Baghdad, in order to identify first year EFL students’ incompetence in writing. This may enhance their achievement by some weekly writing activities. It deals with Iraqi EFL students’ difficulties in writing paragraphs such as descriptive, process, opinion, and factual paragraphs. The study aims to identify these difficulties and to suggest suitable solutions for them. The researcher perceives that it is necessary to enhance students’ skills in writing because it i
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Background: Medical students often face substantial psychological stress, which can increase the risk of substance use, professional detriment, and insufficient patient care. However, substance use in medical students remains understudied in Iraq. This study highlights the prevalence, patterns, risk factors, and negative effects of substance use among medical students at the University of Baghdad. A cross-sectional study involving 414 medical students at the University of Baghdad was conducted. The questionnaire included sociodemographic variables and the Alcohol, Smoking, and Substance Involvement Screening Test to screen for psychoactive substance use. The lifetime prevalence of substance use was 38.9%. Among substance users, 42.8
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Due to the importance of nanotechnology because of its features and applications in various fields, it has become the focus of attention of the world and researchers. In this study, the concept of nanotechnology and nanomaterials was identified, the most important methods of preparing them, as well as the preparation techniques and the most important devices used in their characterization.
Abstract
Objective(s): The study aims to measure the effectiveness of the program on removing dead tissue for burn patients by testing the nurses before the program in addition to testing them again after implementing the educational program.
Methodology: The study is quantitative in nature (one experimental) and will employ pre- and post-testing techniques between October 17, 2020 and March 20, 2022. A non-probability (purposive) sample of 24 nurses working in the Azadi Teaching Hospital's Burns and Plastic Surgery Center was chosen. The experimental survey of nursing practice, a literature review, scientific records, and previous research were all taken into considerat
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