Background: Ceramic veneers represent the treatment of choice in minimally invasive esthetic dentistry; one of the critical factors in their long term success is marginal adaptation. The aim of the present study is to evaluate the marginal gap of ceramic veneers by using two different fabrication techniques and two different designs of preparation. Material and methods: A typodont maxillary central incisor used in the preparation from which metal dies were fabricated, which were in turn used to make forty stone dies. The dies divided into four experimental groups, each group had ten samples: A1: prepared with butt-joint incisal reduction and restored with IPS e.max CAD, A2: prepared with overlapped incisal reduction and restored with IPS e.max CAD. B1: prepared with butt-joint incisal reduction restored with IPS e.max press. B2: prepared with overlapped incisal reduction and restored with IPS e.max press. The marginal gap was measured with direct view technique using digital microscope at a magnification of 230x. Measurements were recorded for four surfaces for each sample and the maximum value was taken to represent that sample. Results: The data were analyzed with two-way ANOVA and independent samples t-tests. These tests revealed highly significant effects of both the preparation design and the technique of fabrication on the marginal gap (p=0.00), with CAD/CAM veneers, group A1 recorded the least marginal gap and pressing group, B2 showed the highest gap values. There was no significant effect of the interaction between the two parameters on the marginal gap. Conclusion: the CAD/CAM veneers with butt joint incisal reduction produced the most accurate margins while the least favorable combination was the pressable ceramic veneers with overlapped incisal reduction.
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
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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
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Background: Odontogenisis is a complex process controlled by dynamic and reciprocal interactions that regulated by various molecules. Thymosin β4 is a small bioactive peptide with wide spectrum biological effects on much cell types. The present study was designed to highlight the effect of synthetic exogenous Tβ4 on developing dental tissue of the upper central teeth of rats, by histological examination and immunohistochemical evaluation of TGFβ1. Materials and method: Thirty six Albino Wister pregnant rat 18control group received intraperitoneal injection of normal saline and the others are experimental group received 50µg/300µl of Tβ4 injection. The animals were sacrificed at periods 16th and 18th day I.U.L and one day p
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An experiment was conducted to study how SAE 50 engine oil contaminated with diesel fuel affects engine performance. The engine oil was contaminated with diesel fuel at concentrations of 0%, 1%, and 3%. The following performance characteristics were studied: brake-specific fuel consumption, brake thermal efficiency, friction power, and exhaust gas temperature. Each treatment was tested three times. The three treatments (0%, 1%, and 3%) were analyzed statistically with a one-way ANOVA model at the 5% probability level to determine if the three treatments produced significant differences in engine performance. The statistical results showed that there were significant differences in engine performance metrics among the three treatments. The 3
... Show MoreA Survey Study Of A Sample Of The Public Of Baghdad Governorate
The current study aimed to identify the most prominent psychological and behavioral repercussions of the exposure of the elderly to the news of the Corona pandemic and to determine the mechanisms of their exposure. On an intended sample on both sides of (Al-Karkh and Al-Rasafa) and the simple random sample was adopted to choose the place of distribution of the questionnaire and the intentional sample.
The research concluded several results, most TV news is still a primary source of information and that most of the sample move between stations to see more information about the pandemic and that the presentation of views confuses the elderly ،There
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The technology in continuous and quick development, that reflects in all parts of our life and interred both scientific and practical fields. Marketing is one of them, a customer’s way to deal with choosing and demanding the product deferent from the traditional way. Some of the buying processes are electronic now, therefore the current research is identifying the digital channels that entered the world of marketing and influenced the activities and types that fall under this name and how it affects in positioning strategy, which is how to install the product or brand in the mind of the customer and was dimensions (brand identity, brand personality, brand communication, brand awareness, brand image), The researcher took t
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