ABSTRACT Background: Bracket rebonding is a common problem in orthodontics which may result in many drawbacks. The aims of this study were to evaluate the effects of application of two enamel protective agents “Icon†and “ProSeal†on shear bond strength before and after rebonding of stainless steel orthodontic brackets using conventional orthodontic adhesive and to assess the site of bond failure. Materials and methods: Fifty sound extracted human upper first premolar teeth were selected and randomly divided into two equal groups; the first time bonding and the rebonding groups (n=30). Each group was subdivided into control, Icon and ProSeal subgroups. The enamel protective agents were applied after etching (preconditioners). Shear bond strength before and after rebonding of stainless steel brackets were assessed using the Universal testing machine and the adhesive remnant index was used to find out the bond failure site using a stereomicroscope. Then the results were statistically analyzed using one-way ANOVA analysis test and T-test. Results: There were no significant differences in the shear bond strength mean values in either group or their corresponding subgroups. Forty percentage of the bond failure in ProSeal groups occurred away from the enamel where 75% of those were at the enamel protective agents/adhesive interface. Conclusions: The application of Icon and ProSeal did not compromise the shear bond strength and the application of the ProSeal may protect the enamel surface from trauma (cracks, chipping or detachment).
In this research want to make analysis for some indicators and it's classifications that related with the teaching process and the scientific level for graduate studies in the university by using analysis of variance for ranked data for repeated measurements instead of the ordinary analysis of variance . We reach many conclusions for the
important classifications for each indicator that has affected on the teaching process. &nb
... Show MoreThe concept of training is no longer traditionally understood Limited organize traditional training courses, but has become a strategic choice in the investment and development of human resources system, attic trying to find the answer to the core problem of the study which
is the extent to which the training process, the traditional form that meets the needs of the company the development of intellectual capital.This research aimstostatementof the impact dimensions the training process(training role, support or top management , training programs, modern technology)of the in components Intellectual Capital(Human Capital, Structural Capital, Customer Capital) and provide the top management of the Company for the development of sci
... Show Moreيجترح الشاعر والت ويتمان انعطافة شعرية لعلاقة الانسان، جسدا وروحا، مع العالم. فهو يستقي الهامه في كتابته لمرثاته (عندما اينع الليلك اخيرا في فناء الدار) من مصادر جمالية واخرى سياسية. ولعل ابرزها تأثره بفكرة الروح الكوني كما جرى طرحها في سياق فلسفة التسامي الامريكية. يظهر ذلك جليا في قصائده التي تتخذ من تماهي روح الانسان مع الطبيعة موضوعة لها. ان فكرة الروح الكوني تلقي ههنا بظلالها على الرتب الانسانية التي
... Show MoreWalt Whitman adds a poetic twist to the relationship of man’s body, soul with the universe. His inspiration in writing his elegy, "When Lilacs Last in the Dooryard Bloom'd," draws on aesthetico-political resources. Major amongst these is his leaning towards the American Transcendentalist idea of the "Over-Soul". The basic topoi in his poems is thus his identification of nature with the soul of man. The idea of the Over-Soul sheds light on the three stages of human loss: suffering, despair, and compensation. Whitman witnessed two political events, the outbreak of the civil war and Abraham Lincoln's death, which were of a particular importance to his life and work: they helped him shape a form and thematic concerns of his own. Buil
... Show MoreA specific, sensitive and simple method was used for the determination of: vitamin B9 (Folic acid) in pure and pharmaceutical formulations using continuous flow injection analysis. The method is based on formation of ion pair compound between folic acid and ammonium molybdate in an aqueous medium to obtain a gray precipitate complex, using homemade; Ayah-6SX1-ST-2D solar cell CFI Analyzer. Optimum parameters was studied to increase the sensitivity for developed method. The linear range for the calibration graph was 0.01-0.6 mMol.L-1 of vitamin B9 and LOD was 131.994 ng/sample with correlation coefficient ( r ) of 0.9810, RSD% was lower than 0.1%, (n=9) for the determination of vitamin B9 at concentration (0.07and 0.5) mMol.L-1 respectiv
... Show MoreIn this work, a deep computational study has been conducted to assign several qualities for the graph . Furthermore, determine the amount of the dihedral subgroups in the Held simple group He through utilizing the attributes of gamma.
The shortage of irrigation water requires specific measures. One of these measures is the application of the rationing system (a period of irrigation followed by a period of drought). This system could have an effect on the behavior and properties of irrigation canals. So, studying rationing system on the irrigation canals is important both in civil engineering and water resources engineering, especially if these channels constructed with gypsum soil. This study includes the calculation of seepage velocity and water content in each cycle (10 days wetting and 10 days of drying). The model is built for this research contains four samples, two samples for untreated soil one of them expos
The second half of the last century witnessed a great scientific revolution that was able to bring about wide changes in various fields, including the field of physical education, which plays a fundamental role in the process of change for the better, and which knocked all the doors of modern science in various aspects and from this perspective we see that students have different capabilities And interests and motives, which require providing a differentiated education, and this depends on the necessity of knowing each student and on the school’s ability to know appropriate strategies for teaching each student so there is no single way to teach so the research problem comes in experimenting with an educational method that works on
... Show MoreThe emergence of artistic movements in Western countries was after the period of modernity. They have introduced a great dialectical problem at the level of thought and discourse, which necessitated a change in the course of the aesthetic discourse into new visions. Thus, the present research aims to identify the aesthetic discourse of pop artists' Art and its representations in the outputs of the students of the Department of Art Education. The theoretical framework included two sections: the first one, what is the aesthetic discourse and the second is the educational bases of the students' outputs. The procedures of the current research included the analytical descriptive approach. The research sample consisted of (4) outputs chosen ac
... Show MoreAbstract The aim of this study is preparing an intellectual map according to the feedback (verbally and writhingly ) in order to learn some skills of floor exercises in the women's artistic gymnastics , In addition to that the aim of this study defines on the impacts of intellectual map according to the feedback approach, and to identify the best group between the three groups study in the learning of skills approach in this study, the researchers used the experimental method, the subject of the study included on students second class in physical education and sport sciences , Baghdad University (2014-2015) , and divided into three groups for teaching skills which was under studied .The species used the specific manner by lot for selection
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