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 paper analyses the relationship between selected macroeconomic variables and gross domestic product (GDP) in Saudi Arabia for the period 1993-2019. Specifically, it measures the effects of interest rate, oil price, inflation rate, budget deficit and money supply on the GDP of Saudi Arabia. The method employs in this paper is based on a descriptive analysis approach and ARDL model through the Bounds testing approach to cointegration. The results of the research reveal that the budget deficit, oil price and money supply have positive significant effects on GDP, while other variables have no effects on GDP and turned out to be insignificant. The findings suggest that both fiscal and monetary policies should be fo
... Show MoreBased on the assumption that the more teachers know about brain science, the better
prepared they will be to make instructional decisions.
Mind Mapping is a powerful tool for assisting any form of writing. Language is an
important device and a very beneficial means for human being to communicate with other
people .Writing is one of the language skills that will never be left in education.
The study aims at investigating the Impact of applying mind mapping technique as a prewriting
tool on Iraqi EFL college students in essay writing. To do so, 60 EFL college students
were divided randomly selected and divided into two groups experimental and control. Prior
to treatment, participants of the both groups were given a
In the present work, the critical micelle concentration (CMC) of the solution of Sodium dodecyl sulfate (SDS) as anionic surfactant, Cocamidopropyl Betaine (CAPB) as amphoteric surfactant, and their mixture have been determined using surface tension and conductivity measurements at a temperature range 293 -323 K. The adsorption and thermodynamic micellization parameters (?G?m, ?G?ads, ?max ,Amin,?cmc ) for individual surfactants was calculated. Rosen model which is focuses on the adsorbed mixed surfactant film at the air/solution interface was used to calculate the interaction parameter ( ?? ) at the interface and the activity coefficients g1 and g2. The results indicate that the CMC of the individual surfactants was affected by
... Show MoreThe objective of the present study is to determine the anti-obesity effects of Akkermansia munciniphila on some biometric measurements. 40 patients were divided into two groups, each with 20 patients; G1 group consumed the probiotic of A. munciphila and G2 consumed placebo capsules. The results showed significant effects on the body weight (p≤ 0.001), which was reduced by a range of -2.29 to -0.7, whereas non-significant differences were observed in the Waist circumferance . The study also showed significant differences (p≤0.001) between the two groups in the levels of cholesterol (287 vs. 285 mg/dl) , whereas the level of Triglyceride significantly decrease
... Show MoreThe aim of the research is to identify the effectiveness of the educational pillars strategy based on Vygotsky's theory in mathematical achievement and information processing of first-grade intermediate students. In pursuit of the research objectives, the experimental method was used, and the quasi-experimental design was used for two equivalent groups, one control group taught traditionally and the other experi-mental taught according to the educational pillars strategy. The research sample consisted of (66) female students from the first intermediate grade, who were inten-tionally chosen after ensuring their equivalence, taking into account several factors, most notably chronological age and their level of mathematics, and they we
... Show MoreThis study aimed to identify attitudes towards mental illness in pregnant female clients to clinics women in the province of Ramallah and Al Bireh, for this purpose applied to study procedures on a sample of (200) of pregnant mothers were selected a sample available, have reached results no statistically significant differences in the level of attitudes towards mental illness due to the variable age in mothers pregnant female clients to clinics for women. Ther were astatistically significant differences in the level of these trends depending on the variable-level scientific research for the benefit of pregnant class university students and older and then high school and so on all areas except the area of social interaction, The results a
... Show MoreThe present work included qualitative study of epiphytic algae on dead and living stems, leaves of the aquatic plant Phragmitesaustralis Trin ex Stand, in Tigris River in AL- Jadria Site in Baghdad during Autumn 2014, Winter 2015, Spring 2015, and Summer 2015. The physical and chemical parameters of River’s water were studied (water temperature, pH, electric conductivity, Salinity, TSS, TDS, turbidity, light intensity, dissolve oxygen, BOD5, alkalinity, total hardness, calcium, magnesium and plant nutrient). A total of 142 isolates of epiphytic algae were identified. Diatoms were dominant by 117 isolates followed by Cyanobacteria (13isolates), Chlorophyta (11 isolates) and Rhodophyta (1 isolate), Variations in the isolates number were rec
... Show MoreThe present research was performed to study the qualitative and quantitative composition of epiphytic algae on the aquatic host plant Ceratophyllum demersum L. Four sites in Tigris River, at Wassit Governorate were covered, during the seasons of Autumn 2017, winter 2018, Spring 2018, and Summer 2018. The study also included measuring the physiochemical parameters (temperature of air and water, pH , water level, EC, salinity, TDS, TSS, dissolved oxygen, BOD5, alkalinity, total hardness, calcium, magnesium, total nitrogen, total phosphourus). The total number of species of epiphytic algae was145 species, 98 species belonging to Bacillariophyceae, followed by 27species of class Cyanophyceae, 19 species of class Chloroph
... Show MoreThe goal of the extant revision was to explore the influence of caffeic acid (CA) extracted from Arctium lappa L. on lipid profile and histology of aorta in rats . Analytical study demonstrated a high percentage of both chlorogenic and caffeic acid in the 80 % methanol extract of the aerial parts (leaves and stems) of Arctium lappa L. from the family Asteraceace. Hypolipidemic activity of caffeic acid was studied against cholesterol induced hypercholesterolemia in Wistar albino rats for thirty days. Rats were separated into normal group (A), hypercholesterolemic positive controller group (B). While, the rest three groups (C, D and E) attended as hypercholesterol
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