ABSTRACT Background: Color changes that are detectable to human eye can affect the esthetic appearance of ceramic veneers. The purpose of this study was to evaluate and compare the effect of artificial accelerated aging on the color of ceramic veneers cemented with different resin cements. Materials and Methods: Sixty discs were prepared with 0.5 mm thickness, 30 discs made from IPS e.max press (Ivoclar Vivadent) and 30 discs were made from VITA Enamic (VITA Zahnfabrik). The discs were cemented with three resin cements: Variolink Veneer MV 0 shade (Ivoclar Vivadent), Rely X veneer Translucent shade (3M ESPE) and NX3 Nexus Clear shade (Kerr Corporation) with 0.1 mm thickness. The spectrophotometer Easyshade Advance was used to measure the color parameters (Lightness, axis a* of chroma and axis b*of chroma) immediately after cementation, after 150 and 300 hours of aging. The specimens were subjected to artificial accelerated aging in Accelerated Weathering Tester. Color change greater than 3.3 was considered unacceptable. One-way ANOVA, paired t-tests and Bonferroni adjusted t-test were used for statistical analysis (p <0.05). Results: Artificial aging caused high significant color change in both ceramic types, but there were non-significant difference in color change among the three resin cements used. The color change was between1.997-14.8 after 150 hours and it was between 2.179-15.68 after 300 hours. The color change of e.max discs after aging were within acceptable limit<3.3 whereas Vita Enamic specimens had shown unacceptable color change >3.3 after aging. Conclusions: The majority of color change after aging related to veneering materials while resin cement have only slight effect on color change after aging. IPS e.max had shown an acceptable color change after aging, so it is suitable for fabrication of restorations in esthetic zone while Vita Enamic should not be used in esthetic zone since it has poor color stability according to the results of this study.
Alopecia (Baldness) is very usual trouble in current time. It is accompanied by an intensive weakening of the scalp's hair and follows a specific pattern. Hereditary predisposition plays a very important role in alopecia despite not completely understood. Alopecia can be typed to various categories according to etiology, may be due to hereditary factors, autoimmune disease, and drugs or chemicals. There are many options of strategies of treatment according to the type and causes of alopecia. Chemical or synthetic medications apply for the management of hair loss are accompanied by a wide range of undesirable effects. Naturally occurring drugs also play important role in alopecia management with minimal side effects.
This study examines the opportunity presented by the COVID-19 pandemic for city planners and leaders to learn from the crisis and build resilient cities with long-term societal, economic, and environmental resilience against future disasters. The research focuses on the relationship between urban planning and policies and the extent of their resilience, particularly in response to pandemic-related disasters. The study evaluates the ability of the city of Baghdad to respond to the pandemic and identifies gaps in its resilience. The study uses the scorecard measurement instrument to examine the disaster resilience of cities, with a focus on governance and financial capability, disaster planning and preparedness, and disaster response
... Show MoreThe textile industries play a prominent role in reviving the national economy, but they are currently suffering from several problems, including the high costs of their activities, the low quality of their production processes, and accordingly, the hexagonal diffraction approach came to help analyze production activities to determine which of them are the most expensive and do not have a benefit or cost greater than Its benefit as a result of waste and losses that accompany its implementation. And by applying to the Iraqi mechanical carpet factory, the research reached several conclusions, the most important of which is the presence of several sources of waste and loss, such as activities and operations that do not add value, whi
... Show MoreDeconstruction is an intellectual stream that emerged as a result of the changes and requirements of the modern era. This stream extended from thought and literature to all arts, and the research included four chapters.
Chapter One: From the research, the research problem was identified in the form of a question: Have the ideas and deconstructive concepts represented in the abstract drawings of the artist Shaker Hassan Al Said?
The importance and limits of the research were reviewed and the goal of the research was to reveal the applications of ideas and deconstructive concepts in the abstract drawings of the artist Shaker Hassan Al Said, in addition to defining the most important terms contained in it.
Chapter Two: Previous
The purpose of this paper is to identifying the level of analytical thinking and its relationship to the skills of response and simple response to the foil weapon for students of the College of Physical Education and Sports Sciences, University of Basra. Achieving the objectives of the research requires the use of a research method, and accordingly, the researchers used the descriptive method using the survey method .The two researchers identified the research community with the students of the third stage - College of Physical Education and Sports Sciences / University of Basra / for the academic year (2021-2022). Their number is (45) students and the two researchers chose the entire research community to represent th
... Show MoreThe research has tackled about an important transformation within the whole region of middle east, especially there were more challenges which revealed under the huge pivotal interests of global powers that ruled the new world order by United states of America ; being very affected over the international and regional relations than any situations appeared previously within political realities. So that, many of variables inside the international scene which happened during of this period of contradicting strategic policies by the process of reforming and restructuring of difficult equations that imposed by international and regional allies and blocs . This article had concentrated over various strategic and political studies which reflect
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The research handles the prominent books of The Weak and Unknown Narrators , which is written by Imam Abu Al-Hasan Al-Daraqutni. It contains a brief introduction about the book and about Abu Bakr Al-Barqani, as well as Abi Mansour Ibn Hamkan.
The research handles the issue of unknown narrators and their relationship to the abandonment stipulated in the preamble to the book.
The research dealt with the identification and comparison between the sayings of Al-Daraqutni and his students - especially Al-Burqani, the publisher of his knowledge, as he is the one who narrated the sayings of Al-Daraqutni. The study concluded that the principle is to abandon the me
... Show MoreThe economic development and intense competition may make economic units neglected the social aspect as a service workers and the environment, the community and focus on the economic side and achieve profitability only, which puts it in a position of accountability of trade unions and bodies, environment, health, civil society organizations and the focus of many studies accounting in order to clarify social activities and disclosed in the financial statements, increasing pressure from multiple parties calling for governments to issue laws and regulations oblige economic units to disclose complete and accurate information in a timely manner for all social activities and be subj
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