Background: Ceramic veneers represent the treatment of choice in minimally invasive esthetic dentistry; one of the critical factors in their long term success is marginal adaptation. The aim of the present study is to evaluate the marginal gap of ceramic veneers by using two different fabrication techniques and two different designs of preparation. Material and methods: A typodont maxillary central incisor used in the preparation from which metal dies were fabricated, which were in turn used to make forty stone dies. The dies divided into four experimental groups, each group had ten samples: A1: prepared with butt-joint incisal reduction and restored with IPS e.max CAD, A2: prepared with overlapped incisal reduction and restored with IPS e.max CAD. B1: prepared with butt-joint incisal reduction restored with IPS e.max press. B2: prepared with overlapped incisal reduction and restored with IPS e.max press. The marginal gap was measured with direct view technique using digital microscope at a magnification of 230x. Measurements were recorded for four surfaces for each sample and the maximum value was taken to represent that sample. Results: The data were analyzed with two-way ANOVA and independent samples t-tests. These tests revealed highly significant effects of both the preparation design and the technique of fabrication on the marginal gap (p=0.00), with CAD/CAM veneers, group A1 recorded the least marginal gap and pressing group, B2 showed the highest gap values. There was no significant effect of the interaction between the two parameters on the marginal gap. Conclusion: the CAD/CAM veneers with butt joint incisal reduction produced the most accurate margins while the least favorable combination was the pressable ceramic veneers with overlapped incisal reduction.
In this paper we show that if ? Xi is monotonically T2-space then each Xi is monotonically T2-space, too. Moreover, we show that if ? Xi is monotonically normal space then each Xi is monotonically normal space, too. Among these results we give a new proof to show that the monotonically T2-space property and monotonically normal space property are hereditary property and topologically property and give an example of T2-space but not monotonically T2-space.
A disagreement has arisen among scholars regarding the ruling on historical statues and monuments in Muslim countries, especially after the Taliban blew up some huge historical statues, and we have witnessed different positions that reach the point of contradiction, each claiming to be right, and now that the crisis has passed and the intensity of the dispute has subsided, I see It is appropriate to discuss this issue calmly, without drifting behind this or that party, to find out the legal position on these statues and monuments.
I presented the most prominent modern opinions related to the subject and discussed them in this research, which I called (Sharia’s position on historical statues and monuments), in which I tried to reach
Cybercrime and risks to children between the problems and solutions( An analytical study in the light of international, Arab and national statistics).
Lies the problem of the study to identify a new type of crime is different from the same traditional character of the crimes or what was customary since human creation up to the information revolution and we enter the era of globalization, which is also called (cyber crime) and their negative impact on all segments of society, especially children, as they the day of the most important social security threats, for all local and international communities alike , and those risks require collective action to various sectors and segments of society ,especially the educated classes in order t
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Vehicular ad hoc network (VANET) is a distinctive form of Mobile Ad hoc Network (MANET) that has attracted increasing research attention recently. The purpose of this study is to comprehensively investigate the elements constituting a VANET system and to address several challenges that have to be overcome to enable a reliable wireless communications within a vehicular environment. Furthermore, the study undertakes a survey of the taxonomy of existing VANET routing protocols, with particular emphasis on the strengths and limitations of these protocols in order to help solve VANET routing issues. Moreover, as mobile users demand constant network access regardless of their location, this study seeks to evaluate various mobility models for vehi
... Show MoreThe relation between faithful, finitely generated, separated acts and the one-to-one operators was investigated, and the associated S-act of coshT and its attributes have been examined. In this paper, we proved for any bounded Linear operators T, VcoshT is faithful and separated S-act, and if a Banach space V is finite-dimensional, VcoshT is infinitely generated.
Tolerance and its impact on building society
In this paper, we introduce the concepts of Large-lifting and Large-supplemented modules as a generalization of lifting and supplemented modules. We also give some results and properties of this new kind of modules.
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The concept of tolerance is gaining its importance in the midst of an international society suffering from violence, wars and internal and international crises. It is practiced by extremist and extremist forces and movements acting in the name of religion to exclude the different Muslim and non-Muslim people according to the unethical practices and methodologies of Islamic law and reality. , Cultural, civilization .. that distinguish our world today. The society today is suffering from the ideas of the intellectual and aesthetic views of the different ideologically, ethnically, culturally and religiously in the world of the South. This is what the end-of-history thesis of Fukuyama and the clash of civilizations represented to Huntington.
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The research deals with solar energy as one of the sources of renewable energies available in Iraq, which can be utilized. The research aims to identify the design pillars of the use of solar energy in street furniture and its relationship to formal variables. The research limits included street furniture manufactured by JCDecaux in Boston during the period 2015-2016, and included the theoretical framework which consists of two sections: solar energy (its beginnings and uses), and solar energy and its uses in Street furniture design.
As far as the research procedures and methodology are concerned, it adopted the descriptive approach in describing and analyzing the sample models in addition to describing and analyzing the sample i
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