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 aim of this investigation is to study and analysis the role of governance in the evaluation of the and social performance of the economic units to be addressed through the concept of corporate governance and then to the social performance and its relationship to corporate governance.
The most important obtained results from this research is that the corporate governance of extreme importance, and derive their importance from being an essential tool to contribute to the transparency and fair disclosure of the financial results of economic units in the fight against financial and administrative corruption in economic units, thus providing protection and confidence of all parties, and the evaluating soci
... Show MoreThe interest in pre-service teacher training has become influential in teaching English as a foreign language, and the purpose of this training course is to prepare qualified teachers to teach effectively through the application of this technique by undergraduate students. This research aims to find out the effect of using the seven principles of good practice as a teaching technique on the fourth stage student-teachers’ performance at the College of Education for Women/University of Baghdad, during the academic year 2017-2018. The sample includes (60) students selected according to the stratified sampling method. The observational checklist used by the department to assess the student teachers’ performance during the practicum perio
... Show MoreThe impact of applying the K-W-L self-scheduling technique on first-year intermediate students' learning of basic volleyball skills, Ayad Ali Hussein*, Israa Fouad Salih
God Almighty has imposed on us obligations and set limits on us, and among these obligations is the prayer, which is considered a pillar of Islam. And recently on the statement of its importance, and through extensive explanations, they elaborated on the statement of its pillars, its obligations, its Sunnahs, its rituals, and its bodies, and it is known that the imam in prayer is an important part of the parts of prayer. Whoever assumes this responsibility must be aware of these conditions, the most important of which is jurisprudence in religion, and there has been a disagreement between the jurists, especially the owners of the four schools of thought, about who is qualified to lead the imamate, and this is within many and wide details
... Show MoreThis research deals with the topic (Fantasy Parody in the Design of the Advertisement) in view of the important role that fantasia plays in designing the most creative and attractive advertisements to the recipients. The research problem lies in accordance with the following question:
What is the Fantasy Parody in the Design of the Advertisement?
It means the imagination, the unfamiliar; and features that emerge for it that distinguish it from other concepts. Fantasy advertisement is creativity in innovative ways, either through collage, merging, or the use of various artistic expressions in terms of intellectual and cultural awareness. When uses in the parody of advertisement, it has helped to come up with an aesthetic experie
There is talk of the Prophet ﷺ proud of his relative, which is the uncle, and the importance of this subject, this search for doctrinal matters related to the two things between us: the interest of the Prophet ﷺ responsible, and also responsible forbidden marriage and marriage as it is forbidden to marry the uncle, and in the uncle language: mother's brother, aunt Her uncle may spend his uncle's nephew, the uncle may embrace his nephew, the uncle shall be the guardian of the little or the small, not to cut off the uncle if he steals from his nephew's money. "
The manufacturing industry in Iraq has faced, during the time stages, several obstacles that have had devastating effects on the Iraqi economy. These obstacles are represented by political events and wars that have led to the depletion of most human and material resources and the suspension of most vital industrial facilities from working, And the occurrence of this major deviation in the process of economic development, For the same reasons, the contributions of the manufacturing sector to the gross domestic product varied fluctuatingly, indicating instability in the growth rates of this sector, On the other hand, the supremacy of the belief that the dominance of oil resources as a main source for creating economic growth and achieving a h
... Show MoreThe lexical connotation is one of the types of connotation that linguists have dealt with, and stipulated in their studies, meaning access to the real meanings of the words, that the lexicon can address after tracing the real meaning of the metaphorical meanings, if any, and this is known to the semantics additional significance, and the rhetorical meaning Figuratively.
The miraculous Qur'an in its systems often refers to the metaphorical uses of the words as well as the real use. The significance of the words in the Holy Qur'an came in a variety of contexts, making each word a special significance that belongs to it exclusively. This is the miracle of the Holy Qur'an. The coming of the slow walk, with its eight words (came, came, cam
Transportation network could be considered as a function of the developmental level of the Iraq, that it is representing the sensitive nerve of the economic activity and the corner stone for the implementation of development plans and developing the spatial structure.
The main theme of this search is to show the characteristics of the regional transportation network in Iraq and to determine the most important effective spatial characteristics and the dimension of that effect negatively or positively. Further this search tries to draw an imagination for the connection between network as a spatial phenomenon and the surrounded natural and human variables within the spatial structure. This search aiming also to determine the nat