Background: The success and maintenance of indirect dental restorations is closely related to the marginal accuracy, which is affected by many factors like preparation design, using of different fabrication techniques, and the time of taking final impression and pouring it. The purpose of this in vitro study was to evaluate the effect of different pouring time of conventional impression on the vertical marginal gap of full contour zirconia crowns in comparison with digital impression technique. Materials and Methods: Forty sound recently extracted human permanent maxillary first premolar teeth of comparable size and shape were collected. Standardized preparation of all teeth samples were carried out to receive full contour zirconia crown restoration with deep chamfer finishing line all around the tooth with (1mm) depth, axial length (4mm) and convergence angle (6 degree). The specimens separated into two groups; Group A; eight specimens were scanned digitally by using Omnicam scanner; Group B; conventional impressions were taken for the remaining thirty two specimens and further subdivided to four groups according to the time of impression pouring; Group B1: PVS were poured after 30 minutes; Group B2: PVS were poured after 24 hours; Group B3: PVS were poured after 7 days; Group B4:PVS were poured after 14 days. Marginal discrepancy was measured at four points at each tooth surface. Sixteen points per tooth were measured using digital microscope at (180X) magnification. One-way ANOVA test and LSD test were carried out to see if there was any significant difference among the means of the conventional impression groups. Independent samples t-test was carried out to examine if there is any significant difference between digital and conventional impression technique. Results: group B2 had the least mean of marginal gap with statistically significant difference when compared to group B1 and statistically highly significant difference when compared to group B3 and B4. There was a statistically highly significant difference in the vertical marginal gap between digital impression technique and conventional impression. Conclusions: the pouring of conventional impression after 24 hours provides better marginal fit than other pouring time. The digital impression provides better marginal fit than conventional impression.
This research studies the rheological properties ( plastic viscosity, yield point and apparent viscosity) of Non-Newtonian fluids under the effect of temperature using different chemical additives, such as (xanthan gum (xc-polymer), carboxyl methyl cellulose ( High and low viscosity ) ,polyacrylamide, polyvinyl alcohol, starch, Quebracho and Chrome Lignosulfonate). The samples were prepared by mixing 22.5g of bentonite with 350 ml of water and adding the additives in four different concentrations (3, 6, 9, 13) g by using Hamilton Beach mixer. The rheological properties of prepared samples were measured by using Fan viscometer model 8-speeds. All the samples were subjected to Bingham plastic model. The temperature range studi
... Show MoreThe current research aims to identify the level of impact of strategic improvisation as an independent variable on organizational health. The dependent variable in the Department of Health of Dhi Qar to reach appropriate mechanisms in order to reach appropriate mechanisms and recommendations proposed to contribute to the achievement of organizational health in the Department of Health of Dhi Qar (the research department) and based on the importance of the subject of research in government institutions and the important and service role of the Department of Health of Dhi Qar in the Iraqi society. The descriptive analytical approach was adopted in the completion of the research based on the opinions of the leaders in the surveyed depa
... Show MoreCurrent research aims to find out:
- Effect of using the active learning in the achievement of third grade intermediate students in mathematics.
- Effect of using of active learning in the tendency towards the study of mathematics for students of third grade intermediate.
In order to achieve the goals of the research, the researcher formulated the following two hypotheses null:
- There is no difference statistically significant at the level of significance (0.05) between two average of degrees to achievement
In this paper, the dynamics of scavenger species predation of both susceptible and infected prey at different rates with prey refuge is mathematically proposed and studied. It is supposed that the disease was spread by direct contact between susceptible prey with infected prey described by Holling type-II infection function. The existence, uniqueness, and boundedness of the solution are investigated. The stability constraints of all equilibrium points are determined. In addition to establishing some sufficient conditions for global stability of them by using suitable Lyapunov functions. Finally, these theoretical results are shown and verified with numerical simulations.
The research aims to employ one of the most important strategies for recovery from the crisis of the Covid-19 pandemic, which ravaged the economies of the entire world and its various sectors, including the banking sector, through financial technology that is based on digital transformation to achieve financial sustainability and the creation of innovative financial value chains in light of the decline in the banking sector as a result of The negative effects of the Covid-19 pandemic, be guided by the relevant international accounting standards to control the risks associated with financial technology. To recover from the Covid-19 crisis, the research came out with a set of recommendations, most notably financial technology from
... Show MoreFolic acid modulates several disorders in humans, pregnancy mostly because of the mitochondria-rich placenta, is a condition that favors oxidative stress.Transitional metals, especially iron, which are particularly abundant in the placenta, are important in the production of free radicals. Adenosine deaminase (ADA), an enzyme essential for the differentiation of lymphoid cells, has been used for monitoring diseases with altered immunity. In the present study we investigated the effect of regular and irregular administered folic acid in the first and second trimester of pregnancy to be compared with non-pregnant women ,and also the effect of regular and irregular using of folic acid supplement on oxidative stress parameters an
... Show MoreAbstract: The study aimed to investigate the effect of oral administration of hot aqueous extract of beetle cocoon Larinus maculatus Faldermann, in a two doses 50 and100mg/Kg/B.wt for 3 and 6 weeks respectively on the levels of serum glucose, weight of body, and lipid profile in male mice Mus musculus. The results revealed that there was a significant (p<0.05) decrease in serum glucose level was dose and period dependent. Weight of body also reduced significantly (p<0.05) with doses and period dependent. The lipid profile level significantly (p<0.05) decreased in dose and period’s manner in each of Total cholesterol (TC), Triglyceride (TG), High Density Lipoprotein- (HDL), Low Density Lipoprotein (LDL), and Very Low Density Lipoprotei
... Show MoreRheumatoid arthritis (RA) is a common inflammatory disease that associated with increased morbidity and mortality due to accelerated atherosclerosis. Rosuvastatin is a unique hydroxy methyl glutaryl Co A (HMGCoA) reductase inhibitor that has anti inflammatory effects.
The aim of this study was to evaluate the effect of rosuvastatin as adjuvant therapy to methotrexate (MTX) on lipid profile and its possible cardioprotective effect in RA patients. A double blinded placebo controlled clinical trial with 8 weeks follow up periods at which 40 patients with active RA using MTX were randomized into 2 groups to receive either rosuvastatin 10mg or placebo as adjuvant therapy to MTX. In addition to twenty healthy subjects as control group.
... Show MoreABSTRACT
Background : The aim of this work is to assess the role of breast sonography and ductography in the evaluation of different causes of nipple discharge.
Methods : The study will be carried out on twenty-five female patients referred to the Radiodiagnosis department at Alexandria Main University Hospital presenting with nipple discharge.
They were divided into two groups:
Group I include 10 patients (40%) with surgically significant nipple discharge who were the patients with unilateral, uniorificial surgically significant colour type nipple discharge .They were investigated by mammography, sonography, and ductography.
Group II include 15 patients
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