Background: Separation and deboning of artificial teeth from denture bases present a major clinical and labortory problem which affect both the patient and the dentist. The optimal bond strength of artificial teeth with denture base reinforced with nanofillers and flexible denture bases and the effect of thermo cycling should be evaluated. This study was conducted to evaluate and compare the shear bond strength of artificial teeth (acrylic and porcelain) with denture bases reinforced by 5% Zirconium oxide nanofillers and flexible bases under the effect of different surface treatments and thermo cycling and comparing the results with conventional water bath cured denture bases. Material and methods: Two types of artificial teeth; acrylic and porcelain were used and prepared for this study. Five specimens of each tooth type were processed to each denture base materials after the application of different surface treatments; these teeth were bonded to heat polymerized, nano composite resin and flexible denture bases. Specimens were thermo cycled and tested for bond strength until fracture with an Instron universal testing machine. Data were analyzed with analysis of variance and student T-test. Photomicrographic examinations were used to identify adhesive and cohesive failures within debonded specimens. Results: The mean force required to fracture the specimens were obviously larger for nanocomposite specimens compared with the heat cured and flexible specimens. The most common failure was cohesive within the tooth or the denture base. With each base material, the artificial teeth which were treated with thinner exhibited highest shear bond strength. Thermocycling had deleterious effect on the flexible denture base specimens. In general, nanocomposite and heat cured groups failed cohesively within the artificial tooth. While the valplastic groups failed adhesively at the tooth denture base interface. Conclusions: Within the limitations of this study, the type of denture base materials and surface treatments of the tooth selected for use may influence the shear bond strength of the tooth to the base. Selection of more compatible combinations of base and artificial teeth may reduce the number of prosthesis fractures and resultant repairs. Key words: acrylic teeth, porcelain teeth, Nano composite denture base, thermo cycling, flexible denture, thinner,
The deficit budget, one of the results of increased public spending for their revenues due to the economic pressures imposed by the interest of the economies of those countries from the need to increase government spending in order to revitalize the national economy and accelerate economic growth rates and provide employment to the growing levels of unemployment in those countries opportunities and what is required to address the current debt crisis (borrowing), which has become a big burden on the governments and the need to move towards the application of austerity spending and tax increases, which inevitably forced those countries will be reflected reduced spending on basic aspects of life and their peoples, particularly earners
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Abstract
Due to the momentum of winning in the streets of the city of Baghdad as a result of the large number of checkpoints so felt researcher to conduct a field visit to find out the main reasons that led to this congestion and to find practical solutions to mitigate wastage winning the arrival time citizen to where you want the least possible time.
This research aims to overcome the difficulties experienced by citizens to reach their places of work and reduce waste at the time of service and waiting time as well as reduce the cost of waiting.
Has emerged study a set of conclusions, including the use of model queue (G / G / C) and the mome
... Show MoreThe research aims to assess the claystone exposed in the Nfayil Formation (Middle Miocene) for Portland cement (P.C.) manufacturing based on mineralogy and geochemistry. The importance of the study is to avoid the miming of the agricultural soils that are mining now for the cement industry. Claystones of Nfayil Formation and the limestone of the Euphrates Formation were used to design the raw mixture as clay to limestone (1:3). The chemical composition (%) of the designed mixture was calculated using the Alligation Alternative Method (A.A.M.) as CaO (65.52), MgO (1.05), SiO2 (21.65), Al2O3 (7.43), Fe2O3 (2.62), Na2O3+K2O (1.52) and SO3 (0.26), which are suitable for P.C. The lime saturation factor (LSF = 92.8), silica saturation fac
... Show MoreThis research is Interested in how the performance and implementation of factory production engine coolants of the General Company for Electrical Industries of its work, and to facilitate the flow of the decisions of senior management and access to all configurations, to ensure differentiation desired and reduce lost sales, resulting from poor scheduling of operations through the application of certain rules of scheduling operations in the production plant Engines Air-cooler, the objectives of research in identifying the best base and working to reduce the time and cost of Same Rules of Process which are considered the most influential of any organization and thr
... Show MoreThe purpose of this paper is to investigate Religious Human Rights Violations. Religious liberty is essential for everyone, everywhere. Because religion is significant to everyone, everywhere. Humans are religious by nature. Our nature drives us to seek answers to deep questions about ultimate things. We cannot live a fully human life unless we are free to seek those answers and live according to the truths we discover. In this study, the researcher used Marsh and White model for analysis A sample of an offensive image of an Islamic concept from the book "Mohammad believes it or else." this book is a comic book written by pseudonym Abdullah Aziz and published by Crescent Moon Publishing company. The book is marked with anti- Mohammad, preju
... Show MoreThe construction of development is required to develop various economic sectors with the necessity to meet the various requirement of both individuals and institutions , or through the import process , which must be commensurate with the needs of the market and the economy and development. But in fact , we find that the process of import in Iraq after 2003 took a turn dangerous excesses on limits of philosophy and objectives of the import , which is reflected at the level of national production as well as the policy of dumping and given and the lack of matching a lot of goods and materials imported for Standards and Measures of quality and stands behind it causes many of them exposure to the market and weak sectors with an overlap betwee
... Show MoreThe research aims at determining the type of educational dimensions to be broadcasted in children's television programs, clarifying the technical forms used in children's TV programs, analyzing the educational dimensions provided by children's television programs, and studying the educational dimensions of children's television programs. The researcher used a sample of children's programs: all of us heroes, which is a daily program on the mbc3 channel as well as the program of Tel flowers on the Algerian channel. The researcher designed an analysis content form included categories of analysis. Spss program was used to process the collected data. The research reached several results; the concentration of educational dimensions in
... Show MoreThe study aims to demonstrate the significance of metaverse technology across various disciplines, academic degrees, scientific fields, and academic titles. It also aims to assess the level of knowledge and understanding of university teachers (research sample) regarding metaverse technology. Hence, the descriptive research methodology was based on the method of statistical survey in the sample. It involved a set of organized scientific steps to deduce data from the reality of the statistical sample and its nature in order to achieve the objectives of the study. In this study, a questionnaire was used as a tool to collect data from a random sample of approximately 121 teachers and instructors from the University of Baghdad. This app
... Show MoreThe Mesopotamian artist conversed the functions of idols with multi-formation, varied pictured and structural significances sign momentum. Each phenomenon had an idol and each event had an idol. So multiplicity contributes in the enrichment of the Mesopotamian thought by the full and comprehensive familiarity of the characterization of the religious space which reached up to realize the start point of creation and formation and specify the concept of unification in such a way that considered as pagan multiplicity and Atheism according to what brought by most of the previous studies.Such a research as ( The Sign Reading of the Structure of Unification in the Civilization of Mesopotamia) aims to clarify this confusion through decoding the
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