Background: White spot lesions are esthetic problems caused by subsurface enamel demineralization that seen as white opacity. Aim of the study: This study aimed to evaluate and to compare the color change after the treatment of the white spot lesions with resin nϔtrton and micro abrasion. Materials and Methods: rtϔ white spot lesions were generated on 48 premolar teeth by the use of a demineralization solution. The teeth were randomly divided using the Diagnodent into three study groups (16 teeth for each group) depending on the depth of the induced lesions: outer enamel, inner enamel and outer dentine. Then each group was fatherly subdivided into two groups (8 teeth for each group) the ϔrst group was treated with resin nϔtrtonǡ while the second one was treated with micro abrasion. For each group, Spectrophotometric examination was performed at three points: baseline (T0), after producing the lesion (T1), and after the treatment (T2). Results: While the mean of ΔE between (T0-T1) showed a snϔ nt difference between the outer and the inner enamel, the outer enamel and the outer dentine, there was no snϔ nt difference between the inner enamel and the outer dentine. On the other hand, the mean of ΔE between (T1-T2) of the three layers of the lesions showed that there was no snϔ nt difference between all the layers when the resin nϔtrton was used. However, there was a snϔ nt difference when the micro abrasion was used. The ΔE between (T0-T2) shows no snϔ nt difference between the three layers of the lesions and between the two materials, (p>0.05). Conclusion: Results of the present study revealed that the deeper the white spot lesion the more the color difference it was, and the resin nϔtrts was excellent in improving the color of the lesion with the same effectiveness as the microabrsion was.
Rosemary (Rosmarinus officinalis L.) is one of the most economically important species of the family Lamiaceae. Rosemary extract was examined by applying 2.2-diphenyl-1- picrylhydrazyl (DPPH) radical-scavenging assays. The result proved that rosemary extract had a higher antioxidant activity by absorption at a wavelength of 517a nm by using three different concentrations (0.5, 1.0 and 3) mg/ml which performed the absorbance at (2. 314, 0. 211 and 0.296) nm in comparison with control (21.8, 92.2 and 90) nm respectively. Results obtained using chemical detection of the phytochemicals indicated the presence of flavonoids, phenols, saponins, Steroids and cardiac in rosemary water extract. Water extracts of R. officinalis leaves were inves
... Show MoreInvasomes are newly developed types of nanovesicles. A vesicular drug delivery system is considered one of the approaches for transdermal delivery to enhance permeation and improve drug bioavailability. Ondansetron is a serotonin receptor antagonist used for treating vomiting associated with different clinical cases. The study aimed to prepare invasomal dispersions for improving permeation of ondansetron across the skin with a controlled release pattern. Twenty-seven formulas of ondansetron-loaded invasomes were prepared by a modified mechanical dispersion method. These formulas were optimized by studying the effect of variables on entrapment efficiency. Vesicle size, polydispersity, zeta potential, in-vitro release and ex-vivo perm
... Show MoreBackground: The accuracy of fitness of any dental casting is imperative for the success of any prosthodontic treatment. From the time that dental casting was first introduced, efforts have been made to produce more accurate and better fitted castings with minimal marginal discrepancy. The aim of this in vitro study was to evaluate the effects of three different investing and burnout techniques on the vertical marginal discrepancies ofceramometalcopings invested with two types of phosphate- bonded investments. Materials and methods: Sixty wax patterns were fabricated on a standardized prepared brass die representing an upper central incisor by the aid of a custom-made split mold. Three different investing and burnout techniques were applied
... Show MoreDisasters, crises and wars are a serious and unforeseen threat. The capacity of the early warning system to monitor such crises is therefore crucial. The ability to make quick decisions in a short time is necessary to prevent crises from occurring. Here, the role and effectiveness of the early warning system emerges through its ability to monitor, record and analyze signals. It can also be evidenced by its ability to immediately convey these indicators to the concerned authorities to take measures that ensure these conflicts and disasters do not worsen. The system’s ability to detect disasters and crises, identify the crisis and its type, and use the scientific method and common sense to deal with it is something that contributes to findi
... Show MoreBackground:sThe aims of this study were to evaluate and compare the ability of three different techniques to obdurate simulated lateral canals, evaluate the effect of the main canal curvature on obturation of lateral canals and compare the gutta-percha penetration between coronal and apical lateral canals. Materials and methods: Resin blocks with 30 straight and 30 curved were used in this study. Each canal has two parallel lateral canals. The main canal has 0.3 mm apical diameter and 0.04 taper. The canals were divided into six groups according to canal curvature and obturation techniques used (n=10): Groups C1 and C2: straight and curved canals obturated with continuous wave technique using E&Q masterTM system. Groups O1 and O2: straight
... Show MoreThe study aims to use the European Excellence Model (EFQM) in assessing the institutional performance of the National Center for Administrative Development and Information Technology in order to determine the gap between the actual reality of the performance of the Center and the standards adopted in the model, in order to know the extent to which the Center seeks to achieve excellence in performance to improve the level of services provided and the adoption of methods Modern and contemporary management in the evaluation of its institutional performance.
The problem of the study was the absence of an institutional performance evaluation system at the centre whereby weaknesses (areas of improvement) and st
... Show MoreThe work is concerned with the characterization of as cast films of neat and UV-stabilized nylon 6,6 by employing FTIR measurements. Band assignment is made for neat and UVstabilized nylon 6,6 using FTIR spectra confirm their molecular structure. UV-stabilizer added to nylon 6,6 has caused reduction in the absorbance of the vibrational bands and thus stabilizes the behavior of the polymer in the end and uses specially in harsh environment.
The In this experimental study, natural stone powder was utilized to improve a cohesive soil’s compaction and strength properties. According to the significant availability of limestone in the globe, it has been chosen for the purpose of the study, in addition to considering the existing rock industry massive waste. Stone powder was used in percentages of 4, 8, 12, 16% replaced from the soil weight in dry state. Some of cohesive soil’s consistency, shear, and compaction properties were depicted after improvement. The outcomes yielded in significant amendments in the experimented geotechnical properties after stone powder addition considering 60 days curing period. Cohesion and friction angle were notably increased by
... Show MoreAddressed the problem of the research is marked (technical openness in the formation of post-modernism - Pop Art an Example) the nature of the technical expansion of the output artifacts postmodern, and the nature of the raw materials taken as components of its sensual. The search came in four sections: general framework for research and identified the research problem and the need for him. With an indication of the importance of his presence. From then select the search goal (revealed openness to hire technical material in the art of Pop Art), followed by the establishment of the three search limits (objectivity, the temporal and spatial) were then determine the terms related to the title. Then provide the theoretical framework and indi
... Show MoreDrilling with casing (DWC) can be considered as a modern drilling technique in which both of drilling and casing operations done in the same time by using the casing to transfer the hydraulic and mechanical power to the bit instead of traditional drilling string. To overcome oil well control, minimizing the total cost through enhancing drilling efficiency, drilling with casing was proposed as an enabling technology.
Two surface sections (17 1/2 - and 12 1/4- inch) were drilled successfully in Rumaila oil field with casing strings which reached 655m and 1524m measured depths respectively.
By using DWC technique, the total drill/case phase time was reduced up to 20% comparing to conventional
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