Background: Esthetic treatment is the options of patient seeking orthodontic treatment. Therefore this study was conducted to measure the concentration of Aluminum, Nickel, Chromium and Iron ions released from combination of monocrysralline brackets with different arch wires immersed in artificial saliva at different duration, to evaluate the corrosion point on different parts of the orthodontic appliances before and after immersion in artificial saliva, and to evaluate the corrosion potential of each group of the orthodontic appliances. Material and methods: Eighty orthodontic sets prepared. Each set represents half fixed orthodontic appliance, from the central incisor to the first molar, for the maxillary arch, each set consisted of molar band, five brackets, half arch wire and ligature elastic.These sets are divided into two groups: Group A: with monocrystalline brackets divided into five subgroups (each subgroup has ten sets), but differ in arch wires, as numbered stainless steel, nickel-titanium, thermally activated, coated stainless steel and coated nickel-titanium arch wires respectively. Group B: with stainless steel brackets divided into three subgroups (also each subgroup has ten sets), but differ in arch wires, as numberedstainless steel, nickel-titanium, and thermally activated arch wires respectively. Used optical microscope to check the corrosion points, and used potentiostat techniques to indicate corrosion rate and tendency. Results: The greatest concentration of Aluminum and nickel ions release during the 1st week in group A, then sharply decreased in the 2nd week. The release of chromium ion released increase with increase intervals, while iron ion released decrease with increase time. Both nickel and chromium ions increase with increase intervals in group B,while iron increase to the maximum at 3rd weeks, then began to degrease. Optical microscope displayed pitting, crevices, and intergranular corrosion. Potentiostat techniques indicated that increase corrosion when used stainless steel and coated nickel titanium than others arch wires with group A, while corrosion increase with nickel titanium than stainless steel arch wires with group B. Conclusions: Non-significant difference in the total nickel, chromium and iron release in group B. Aluminum and iron increase in A4 and A5, while nickel and chromium increase in A1 and A2.The total released amounts of metals ions in both groups were less than the amounts of daily intake.
Praise be to God, we praise Him, we seek His help, we seek His forgiveness, and we seek refuge in God from the evils of ourselves and our bad deeds. . The marriage contract, like other contracts, gives rise to reciprocal rights and duties that bind both the husband and the wife, pursuant to the principle of balance, equivalence, and the equality of the parties to the contract on which every contract is based. . That is, women have rights over men similar to what men have over women, or that the basis for estimating these rights and duties is custom based on the nature of both men and women. The Iraqi Personal Status Law stipulates all the financial rights that the wife is entitled to from her husband: namely, the dowry and alimony. As fo
... Show MoreThis paper is devoted to the discussion the relationships of connectedness between some types of graphs (resp. digraph) and Gm-closure spaces by using graph closure operators.
The research sheds light on the subject of phraseology as an important field to present metaphysical issues with contemporary scientific discourse. (Primary psychology) It does not apply with the reality of this science and therefore some tried to call it other names such as (Alsai), a unit of measurement of energy activity of things and assets. It was also called metaphysics or metaphysics, but it eventually settled on parapsychology. We try to win Islam and religious concepts with contemporary scientific discourse. The researcher discussed issues that modern science was unable to comprehend and interpreted. He used these subjects to prove the truths of religion and faith. Modern times because the whole universe miracles or as Imam Ghaz
... Show MoreDiesel generators is widely used in Iraq for the purpose of maintaining electric power demand. Large number of operators engaged in this work encounters high level of noise generated by back pack type diesel generators used for this purpose. High level of noise exposure gives different kinds of ill effect on human operators. Exact nature of deteriorated work performance is not known., in present research , quastionaire was adsministered 86 repondents in Baghdad city were exposured to wide range of noise level (80-110) dB(A) with different ages and they have different skill discretion levels. Noise levels A-weigthed decibles dB(A) were measured over 8 weeks two times aday during the 2019 summer using a sound level meter.For predicting the wo
... Show MorePraise be to God, Lord of the worlds, and prayers and peace be upon His messenger, the mercy of the worlds.
As for after ....
It is clear from the legal texts in the Noble Qur’an and the Sunnah of the Prophet, that Islam is a method that interferes in everything in beliefs, worship, behavior and transactions, and it forbids excess and extremism and mistrust of people and looking at them through a black lens, self-conceit and contempt of others.
In our research, we will try, God willing, to study the phenomenon of religious extremism with its comprehensive dimensions, the position of Islam on it through the verses and hadiths discussed by it, and the diagnosis of the reasons for its emergence and emergence, because if we learn
The research deals with the global ceramic achievement within the international forums in the past decades. As follows، showing and presenting the aesthetic and intellectual values leading to common constants that establish international artistic studies that achieve the purpose of circulation and marketing of artworks. Contemporary global plastic art has witnessed a number of technical and social transformations and changes at the technical and pragmatic levels under the pressure of the changing and accelerating tide towards technical، cognitive، social and cultural concepts.
The second chapter came to the first topic: deliberative and commoditization، and the second topic: the deliberativeness of contemporary global ceramics.
The problem of research tagged: (metaphor and its transformations in the surreal drawing) dealt with the nature of the concept of metaphor and the mechanisms of its work in the contemporary global achievement. The research came in four chapters: The first chapter was concerned with the systematic framework for the research represented by the problem of the research, as it was manifested through this study by metaphor and its transformations, which were associated with the Surreal drawing papers in Europe. The goal of the study has been crystallized with the following:
Exposing metaphor and its transformations in the visual system of the surreal drawing.
As for the limits of the research, I was interested in analyzing video mod
The purpose of this paper is to shed light on the concept of fuzzy logic ,its application in linguistics ,especially in language teaching and the fuzziness of some lexical items in English.
Fuzziness means that the semantic boundaries of some lexical items are indefinite and ideterminate.Fuzzy logic provides a very precise approach for dealing with this indeterminacy and uncertainty which grows (among other reasons) out of human behavior and the effect of society.
The concept of fuzzy logic has emerged in the development of the theory of fuzzy set by Lotfi Zadeh(a professor of computer science at the university of California) in 1965.It can be thought of as the application side of the fuzzy set theory. In linguistics, few scholars
The research topic was chosen as a result of the importance of human resource in business organizations in general and the industrial process in particular. Without the human resource, business organizations cannot continue and achieve success and excellence, and the research problem has been diagnosed in the lack of sales of General Cement Company’s northern products, despite their distinctiveness, standing, and reputation in The market and its products with standard specifications, and through this problem, the following questions were raised: &nbs
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