Background: One common undesirable side effect of orthodontic treatment with fixed appliances is the development of incipient caries lesions around brackets, particularly in patients with poor oral hygiene. Different methods have been used to prevent demineralization; the recent effort to improve the resistance against the demineralization is by the application of lasers. Materials and method: Thirty human premolars extracted for orthodontic purposes were used to test the effect of two energy level of ER-YAG laser on enamel resistance to demineralization. The brackets were bonded on the teeth and all the labial surface excluding 2 mm area gingival to the brackets were painted with acid resistance varnish. Three groups were generated. The first group was the control group (A), with no treatment was performed. In group II (B)and groups III (C); teeth were irradiated by ER-YAG laser of 200, 60 mj energy respectively. All the teeth were individually subjected to acid challenge cycle for 30 days. After debonding longitudinal sections were taken and examined under stereomicroscope. The enamel demineralization evaluation was done by taking the average of three depths at the centre of the artificial lesion. Also the enamel surface was classified by an experienced investigator according to acid etch pattern. Comparisons of the average depth values of the groups were performed with ANOVA and LSD tests. The statistical significance level was set at p ≤ 0.05. Results: The results revealed that average lesion depth was significantly deeper at the control group than the laser groups, and its significantly deeper in group (B) 200 mj than in group (C) 60 mj, enamel surfaces showed deeper pits and craters than in control group. Conclusions: the decrease in artificial caries lesion depth associated with use of the two laser energy level support the ER-YAG laser as a tool to increase enamel resistance to demineralization and white spot lesion prevention. Key words: Demineralization, ER-YAG, laser.
The study aimed to : - To determine whether there are significant differences between Fartlek training and the increase in the molecular biology (VEGF - basal fibroblast growth factor) for arena and field players in an (800m) youth event. - Determine whether there are statistically significant differences between Fartlek training and the increase in molecular biology and some physical variables for the players (800m) in the arena and field for youth. - Determine whether the Fartlek training method is the most appropriate to achieve statistically significant differences in the research variables for the players (800m) in the arena and field for youth. The researchers used the experimental method for its suitability and the nature of the rese
... Show MoreThe research aims to identify intelligence spiritual among a sample of students Baghdad University as well as to identify the differences between students in intelligence spiritual according to variable type (male - female), and variable area of study (Science - a human) and variable (First grade - fourth grade), The research sample consisted of (300) students, were applied scale search - a spiritual Intelligence Scale (prepared by the researcher), has resulted in the search results for: -
The students of the University of Baghdad (sample) enjoyed a high level of spiritual intelligence.
- There are no differences between males and females in the spiritual intelligence.
- There
This research aims to know the role of strategic flexibility in achieving organizational effectiveness by studying the dimensions of strategic flexibility (capacity flexibility, resource flexibility, information flexibility, and coordination flexibility) on the dimensions of organization effectiveness (environmental adaptation, productivity and achieving goals) through an analytical study conducted in six directorates in the office of the Iraqi Ministry of Education.
The research problem was represented in the form of questions, the most prominent of which was "What is the role of strategic flexibility in achieving organization effectiveness?" The descriptive analytical approach was relied on in applying
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Abstract:
The aim of this research to try to determine the type of expected relationship between inflation as the explanatory variable and market performance as a dependent variable, for that used data issued and published by the Central Bank of Iraq and the Iraqi Stock Exchange for a sample consisting of (159) observations using the intentional or intentional sampling method for the period extending between the months (January 2010 to March 2023), in the light of each of the Consumer Price Index (CPI), the Iraqi Stock Exchange Index, the number of traded shares and the number of market capital shares to ex
... Show MoreTo investigate the research objectives, the researchers put the following hypothesis:
There was no statistically significant difference at the level of (0.05) between the average score of the students of the experimental group who studied the language of rhetoric according to model of learning method, and the average score of the students of the control group who studied the same article in the traditional way acquiring rhetorical concept. The researchers relied on the experimental design with the partial setting of the post-test, which depends on the experimental group that is taught using the model of the learning method, and the control group taught using the traditional method.
... Show MoreThe economical units in the world face great and rapid challenges in all aspects, a matter that requires facing these challenges throughout continuous improving and developing in their performance to keep their competitive position "place".
The Benchmarking Technique is one of the modern managerial tools that are proved to be successful in application throughout making continuous comparisons between products or services and the best – performance levels the compete with it . This is achieved to develop its performance and give it the competitive criterion with which it faces its competitors.
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The Urban Residential has developed and changed in different periods of time with successive and gradual shifts, as it cast a shadow over the characterization of modern urbanism in Iraq. The semi-total absence of the governing legislation of urbanization as well as the weakness of the State's role of supervisory in addition to neglecting urban heritage contributed in offering a strange environment in relation to its traditional identity. That was increased by the pressure of the using urban environment as a result of the increasing of population as well as the growth of people’s needs. The research aims to provide an objective view for a mechanism of the application of urban legislation to monitor the implementation o
... Show MoreAbstract:
One of the most prominent historical stage feature that is well- known
nowadays in the world is democracy issue. This issue gives man the right to
reflect his concept and notions . It,s the world of freedom , human right and
liberation of women. This leads to the principle of equality between women
and men which is put in the top of liberty and Improvement lists .
Improvement can be defined as a group of means and ways that is
used to direct human work to improve their level of life economically and
socially .
This study contains three sections, the first presents the social state of
women in pre-history period . And the second section presents the theory of
improvement as an important social ph
Abstract
This research shows the history of political conflicts in Zimbabwe, the
merits of the political struggle for power in this country since the British
colonial period, especially after the British administration announced that
Zimbabwe is a local colony of the British Crown in 1923, as the settlement
process against the wide white deprive local people to own and lease land
and low income, as well as the 1961 Constitution, which granted access to
the white powers in accordance with the authority of the top menu for the
existing lower allocated to blacks.
These events and factors led to a national rejection in Zimbabwe,
which crystallized in the form of parties and political organizations through the
The launch of the EU’s Eastern Partnership in 2009 intended to signal a new, elevated level of EU engagement with its Eastern neighborhood. Yet there remain several long-simmering and potentially destabilizing conflicts in the region, with which EU engagement thus far has been sporadic at best. The Union’s use of its Common Security and Defense Policy (CSDP) in the region and to help solve these disputes has been particularly ad hoc and inconsistent, wracked by inter-institutional incoherence and undermined by Member States’ inability to agree on a broad strategic vision for engagement with the area.
The three CSDP missions deployed to the region thus far have all suffered from this incoherence to various extents. In particu
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