Background: The desire for an attractive appearing fixed orthodontic appliance fueled the use of ceramic brackets and clear accessories. Elastics are one of the most versatile materials available to orthodontists so studying their effect on the esthetic appearance is important. This an in vivo study, conducted to evaluate the effect of exposing stretched clear elastomeric ligatures to the oral environment from four different companies (OrthoTechnology, Morelli, Ortho Organizer, and Ormco). Materials and Methods: A total of 240 elastomeric modules were examined, 60 modules from each brand. Each of the 60 patients enrolled in the study, received 4 elastomeric modules on the 4 lower incisors, one from each brand. The specimens were placed on the teeth for 1, 2 and 4 weeks. After removal each module was kept in a sealed plastic bag and prepared for imaging and color measurement. Color measurements were made before and after use of the specimens. Images were taken by a cellular attachable microscope connected to a mobile phone with special J-cam program and the color change was calculated according to CIE Labcolor spaces system by the Adobe Photoshop program. The resulting data were statistically analyzed using ANOVA, LSD and Chi square tests. Results: The results showed that, all the elastomeric ligatures discolored after use. The discoloration increased with an increased incubation period in the mouth reaching the peak at 4 weeks interval and the yellowness index was the mostly effected color component. Elastomeric ligatures from Morelli brand were the most prone to discoloration, while Ortho Organizers and Ormco ligatures were the least prone to discoloration with the presence of large individual variation. Conclusion: It is necessary to alert the patient about the color changes that the clear ligatures experienced and the staining effect of certain foods. The orthodontist should select brands that are more resistant to color changes.
A real method of predication brake pad wear ,could lead to substantiol economies of time and money. This paper describes how such a procedure has been used and gives the results to establish is reliability by comparing the predicted wear with that which actually occurs in an existing service. The experimental work was carried out on three different commercial samples ,tested under different operation conditions (speed,load,time...etc)using a test ring especially modified for this purpose. Abrasive wear is mainly studied , since it is the type of wear that takes place in such arrangements. Samples wear tested in presences of sand or mud between the mating surfaces under different operational conditions of speed, load and braking time .Mec
... Show MoreTraining has occupied a leading position in a large number of developed and developing countries alike in order to develop the skills of workers in line with the changes and developments of the era, including monitoring compliance in banks, which is one of the most important jobs in banking work to trailing and monitor the bank’s compliance with laws, regulations and instructions in order to achieve its goals Therefore, the problem of this research focuses on the following question: What is the role of training in enhancing banking compliance at the present time? In order to clarify the relationship between the main and sub-research variables, two main hypotheses and three sub-hypotheses were formulated for each hypothesis, and t
... Show MoreBackground: The present in-vitro study was undertaken to evaluate and compare fracture resistance of weakened endodontically treated premolars with class II MOD cavities restored with different bulk fill composite restorations (EverX posterior, Alert, Tetric EvoCeram Bulk Fill, and SDR). The type and mode of fracture were also assessed for all the experimental groups. Materials and Method: Forty-eight human adult maxillary premolar teeth were selected for this study. Standardized extensive class II MOD cavities with endodontic treatment were prepared for all teeth, except those that were saved as intact control. The teeth were divided into six groups of eight teeth each (n=8): (Group 1) intact control group, (Group 2) unrestored teeth with
... Show MoreBackground: Most prevalent chronic liver disease in developed and developing nations is non-alcoholic fatty liver disease. From fatty liver, which often has benign, non-progressive clinical history, to non-alcoholic steatohepatitis, a more serious variant of fatty liver that can lead to cirrhosis and end-stage liver disease, non-alcoholic fatty liver disease encompasses broad spectrum of diseases. The gold standard for determining extent of hepatic fibrosis is still liver biopsy; however, number of noninvasive tests have been established to make diagnosis and assess effectiveness of treatment.
Objective: Aim of study was to assess effectiveness of the combination of fibroscan and
... Show MoreNowadays, the worldwide issue of the environment occupies the minds not only of ecological experts and politicians but also is addressed in cultural fields and literature in particular. The conceptualization of ecocriticism, whether in the ecological field or cultural studies, has come as a response to the increasing public awareness of numerous environmental crises. Most ecocritics regard John Clare (1793-1864) as a 'proto-ecological' British poet since his poetry incorporates ecological issues which were not then categorized as they are now. The study offers a precise illustration of ecocriticism coupled with a number of the most significant ecological concepts proven in selected poems by John Clare. The ecocritical reading of Clare's po
... Show MoreIn the present study, multi-walled carbon nanotubes (MWCNTs) with outside diameters of< 8 nm and 20−30 nm were covalently functionalized with β-Alanine using a novel synthesis procedure. The functionalization process was proved successful using Raman spectroscopy, FTIR, and TEM. Utilizing the two-step method with ultrasonication, the MWCNTs treated with β-Alanine (Ala-MWCNTs) with weight concentrations of 0.025%, 0.05%, 0.075%, and 0.1% were dispersed in distilled water to prepare water-based nanofluids. The aqueous colloidal dispersions of pristine MWCNTs were unstable. While for Ala-MWCNTs and after> 50 days from preparation, higher colloidal stability was obtained up to relative concentration of 0.955 and 0.939 for the 0.075-wt% samp
... Show MoreGel polymer electrolytes (GPEs) have drawn a lot of interest due to their special qualities, which include high conductivity that is comparable to liquid electrolytes, excellent mechanical stability, and high flexibility. Using the solution casting approach, we have synthesized copper ion conducting gel polymer electrolyte (GPE) films made of polyvinyl alcohol (PVA) as the polymer host. An ionic salt, copper sulphate (CuSO 4 ), and a plasticizing solvent, PANI/ [BMIM] [BF 4 ] polyionic liquid, were employed. The structural, electrical, and electrochemical properties of the GPE films were carefully examined. The significant XRD crystalline peak decreased and disappeared upon the addition of PANI/[BMIM] [BF 4 ] polyionic liquid, suggesting th
... Show MoreThe self-evident truth existing in today's business environment is the continuity of change and its continuity and turmoil, also its increase over time as it is more abundant, abundant, wide and complex than ever before, and it is the dominant feature in the business environment, as different organizations and operating units can find themselves shifting from the top to the bottom. And then it requires its departments to strive to adapt to these rapid and turbulent shifts and changes by bringing about a series of organizational and adaptive changes that are not limited to one organizational aspect only but rather include all organizational components. Accordingly, this research came to determine the readiness of public organizations to chan
... Show MoreThe research seeks to find out the extent of the coverage of the Mosul press to the issues of psychological and social effects of the organization "IS" on the community of Mosul, by analyzing the content of the newspapers “Economic City” and “Mosul News”. As well as to stand at the types of psychological and social effects and their repercussions on the Mosul community including figures, statistics and evidence that were covered in the theoretical study of these topics.
This study is the first scientific diagnosis to reveal the size and types of psychological and social effects of the “ISIS” organization through what was monitored by the Mosul press. The study seeks to draw the attention of officials, decision-m
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