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.
Faced economic units face the option of restoring the capital budget annually, and the information provided for the preparation of these budgets, including financial and non-financial aspects have an important impact in the numbers of these budgets, and these units differ in the ability of their own accounting systems to maintain this information. The aim of this research is to investigate the volume of accounting information that is relied on and the reasons for the differences between one unit and another in the various economic sectors in the Iraqi environment.
The most important results of the research is the weakness of the adoption of decision makers in the Iraqi environment and lack of sufficient attention in the decision-
... Show MoreThe curriculum is considered one of the most important corners for the educational process, it participates in achieving the educational equilibrium between its elements.
The curriculum of (History of the Art) in the college of Art Education / dept. of plastic art education and ceramic as the other curriculums and due to the subject of history of the art develop the knowledge, taste and experiment for art studier also this subject has a direct relation with practical educational activities like colors and growth the knowledge of the student in field of contents and symbols and evidences of meaning in old , medium and contemporary arts, due to the fact that this curriculum has been applied since long time more than four years, and
... Show MoreIn the name of God the Merciful
Praise be to God and the Hall and Peace Uncle Prophet Muhammad and blindness Alo and companions
Money is the lifeblood and a reason for living. An individual cannot live without money to make it
It is only through the necessities of life and the state that it can perform its duties and functions only
As money is so important, the state must regulate the balance of revenues
And expenses in order to avoid failure in Mizanitia, but perhaps the country may be exposed to crises
An exception that leads to misappropriation in the general Mizanitia and the Islamic Shari'ah is valid for Makkah
Time and place for all circumstances has created several ways to address the budget defici
Background: This study is to evaluate the necessity of prescribing prophylactic antibiotics for nasal packing in spontaneous epistaxis. There are few published papers of infective complications in such patients.
Methods: This prospective study analysed 149 consecutive patients admitted to AL-Kindy teaching hospital with spontaneous, epistaxis, who underwent nasal packing over 2 years period . in the first year, 78 patients received prophylactic antibiotics , In the second year 71 patients were not given prophylatic antibiotics. Exclusion criteria included antibiotics prescribed for unrelated pathology and post-operative epistaxis. Signs and symptoms of acute otitis m
... Show MoreThe impact of Jurisprudence Rules in Addressing Contemporary security Challenges
Islamic jurisprudence is related to various fields of knowledge, as it is a science of great value, great in impact, and among the most prominent features of jurisprudence comes the jurisprudence rules. It regulates the principles of the doctrine for the jurist. Therefore, the main this research focuses on (the impact of jurisprudence rules in addressing contemporary security challenges). It is the relationship between jurisprudence rules and achieving security. Its fruit would be a statement of the distinguished impact of jurisprudence rules on the stability of the country, and its leading role in maintaining, strengthening, and pre
... Show MoreThe cities are not yet a temporal status in the process of the human and civilization development. The cities consider as a life pattern, this mean that people cannot live without cities, which surround us. Several phenomena like globalization, revolution of information, technical development, increased of consumption, do not confirmed without the living in cities. The urbanization – in its simple meaning – means transferring from rural community to city community. In other word, it means that socioeconomic changes happened subject to the patterns and conditions of the urban life. Each government depend a certain policy, this policy contains set of plans and programs, that targeting to affect the population factors and the st
... Show MoreAlkaloids are a group of naturally occurring chemical compounds that contain mostly basic nitrogen atoms . They are a large family of compounds synthesized by plants in addition to the bacteria, fungi, and animals, they often have pharmacological effects. The aim of this study is to isolate and identified alkaloids in a newly studied, wild Iraqi plant named
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