Background: This clinical trial aims to evaluate the color changes of direct resin composite veneer (DCV) restorations based on spectrophotometric analysis of 4 different types of resin composites between the baseline immediately after polishing and after one year of follow-up. Materials and methods: 28 patients were assessed for eligibility for participation, aged between 18 and 38 years old, who indicated for DCV restorations in anterior maxillary teeth were considered for participation in this study. In total, 25 patients who met the inclusion criteria were selected (6 males and 19 females, mean age: 20.9 at the time of restoration placement), and 3 patients were excluded. Participants were divided into four groups based on the type of composite resin used for restorations. Group 1 nanohybrid Ips Empress direct (Ivoclar Vivadent)](IPS) (13 restorations/6 patients), group 2 microfilled [Essentia (GC cooperation Japan)](ES) (14 restorations / 7 patients), group 3 supra-nano filled [ Estelite ∑ Quick (Tokuyama, Tokyo, Japan)](EQ) (17 restorations / 7 patients) and group 4 nanofill [Filtek Ultimate (3M ESPE)](FU) (13 restorations / 5 patients). Baseline Color measurements were performed with a spectrophotometer immediately after finishing and polishing (baseline), and after one year of recall, color change (ΔE) from baseline values and after one year of follow-up of DCVs were calculated according to CIELab color coordinates. For this, a silicone mold was fabricated for each patient and used as a guide for each measurement to standardize the site of the readings. Statistical analysis of the data was applied using the Kruskal-Wallis test with Dunn-Bonferroni posthoc test after controlling the distribution of data in terms of normality with the Shapiro Wilk test. Results: At the end of one year,25 participants(57restorations) were followed up. The mean ΔE of IPS, EQ, and FU composites were higher than the ES composite resin, but there was no statically significant difference between all types of composites (P> 0.05). There was no statistically significant difference in the mean ΔL* between any types of composite resin (p> 0.05). There was a significant change in Δa* and Δb* after a one-year recall for all the types of DCV restorations (p < 0.05). Conclusion: After one year of follow-up, the spectrophotometer measurements of direct resin composite veneer restorations, it was concluded no difference between the mean ΔE of ES, IPS, FU, and EQ resin composite. ES (Microfilled hybrid) showed a lower mean ΔE value compared to the other groups. All groups of resin composite showed color changes within clinically acceptable levels after a one-year follow-up.
The present investigation is concerned for the purification of impure zinc oxide (80-85 wt %) by using petroleum coke
(carbon content is 76 wt %) as reducing agent for the impure zinc oxide to provide pure zinc vapor, which will be
oxidized later by air to the pure zinc oxide.
The operating conditions of the reaction were studied in detail which are, reaction time within the range (10 to 30 min),
reaction temperature (900 to 1100 oC), air flow rate (0.2 to 1 l/min) and weight percentage of the reducing agent
(petroleum coke) in the feed (14 to 30 wt %).
The best operating conditions were (30 min) for the reaction time, (1100 oC) for the reaction temperature, (1 l/min) for
the air flow rate, and (30 wt %) of reducing
In this work, laboratory experiments were carried out to verify direct contact membrane distillation system’s performance in highly saline water desalination. The study included the investigation of various operating conditions, like feed flow rate, temperature and concentration of NaCl solution and their impact on the permeation flux were discussed. 16 cm2 of a flat sheet membrane module with commercial poly-tetra-fluoroethylene (PTFE) membrane, which has 0.22 μm pore size, 96 µm thickness and 78% average porosity, was used. A high salt rejection factor was obtained greater than 99.9%, and the permeation flux up to 17.27 kg/m2.h was achieved at 65°C for hot feed side and 20°C for cold side stream.
Recently, Qatar, a well-known oil production country, has been convinced as a successful case in attracting foreign direct investment (FDI) as a smaller economy. This paper aims to investigate how FDI inflows affect Qatar’s business cycles. Time series data was selected from 1990 to 2010 as available. The VAR Impulse Responses and the Granger Causality test were mainly employed by using Eviews. The derived result shows that the FDI inflows and the economic growth in Qatar interact with each other in a relatively long term.
Background: Dental caries is one of the most prevalent chronic diseases of people worldwide that lead to the pain and disability across all age groups and still consider as a major cause of tooth loss. The aim of this study was to assess the prevalence and severity of dental caries and treatment needs among school children in Heet city. Materiales and methods: The sample included all school children at age of (12 years old) males and females from urban areas in Heet city. Diagnosis and recording of dental caries and treatment needs were done according to the criteria of WHO. Results: The prevalence of dental caries was (90.2%). The DMFS/dmfs values were (5.85±0.168, 1.57±0.146) respectively for the total sample. Females were foun
... Show MoreAbstract: This research aims to investigate and analyze the most pressing issues facing the Iraqi economy, namely economic stability and inclusive growth Consequently, the present study investigates the effect of inflation and unemployment, which are significant contributors to economic instability, on inclusive growth dimensions such as GDP, education, health, governance, poverty, income inequality, and environmental performance. From 1991 to 2021, secondary data were collected using World Bank Indicators (WDI) and Organization for Economic Cooperation and Development (OECD) databases. The researchers also employed the autoregressive distributed lag (ARDL) model to determine the relationship between variables. The study revealed that fluct
... Show MoreBackground. Aneurysms of the distal anterior cerebral artery (DACA) are uncommon; they often form near the pericallosal-callosomarginal junction and are typically small. To our knowledge, giant DACA aneurysms developing from the more distant parts of the anterior cerebral artery (ACA), A4-5, have been described only once in the literature. Case description. A 66-year-old gentleman reported with a brief loss of consciousness followed by weakness in his right lower leg. The patient was admitted with a Glasgow Coma Score (GCS) of 15. A computed tomography (CT) scan of the head revealed a left hyperdense mass in the frontal parasagittal supracallosal region. Contrast MRI revealed a heterogeneously enhancing mass measuring 35x30x25 mm. C
... Show MoreMembrane distillation (MD) is a hopeful desalination technique for brine (salty) water. In this research, Direct Contact Membrane Distillation (DCMD) and Air Gap Membrane Distillation (AGMD) will be used. The sample used is from Shat Al –Arab water (TDS=2430 mg/l). A polyvinylidene fluoride (PVDF) flat sheet membrane was used as a flat sheet form with a plate and frame cell. Several parameters were studied, such as; operation time, feed temperature, permeate temperature, feed flow rate. The results showed that with time, the flux decreases because of the accumulated fouling and scaling on the membrane surface. Feed temperature and feed flow rate had a positive effect on the permeate flux, while permeate temperatu
... Show MoreFinancial inclusion refers to the access of financial services at low cost and high-quality from the formal financial sector to all segments of society, especially marginalized groups, and then use and benefit from them. Financial inclusion is also associated with banking stability, as well as with financial integrity and financial protection for the consumer, therefore, it achieves a number of objectives, the most important of which is to support and enhance banking stability. This is what made it attract the attention of many countries and central banks recently.
The study aims to show the impact of financial inclusion indicators on ban
... Show MoreMillions of lives might be saved if stained tissues could be detected quickly. Image classification algorithms may be used to detect the shape of cancerous cells, which is crucial in determining the severity of the disease. With the rapid advancement of digital technology, digital images now play a critical role in the current day, with rapid applications in the medical and visualization fields. Tissue segmentation in whole-slide photographs is a crucial task in digital pathology, as it is necessary for fast and accurate computer-aided diagnoses. When a tissue picture is stained with eosin and hematoxylin, precise tissue segmentation is especially important for a successful diagnosis. This kind of staining aids pathologists in disti
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