Background: This study aimed to evaluate the effect of zirconia different surface treatments (primer, sandblast with 50μmAl2O3, Er,Cr:YSGG laser) on shear bond strength between zirconia surface and resin cement. Material and methods: Sixty presintered Y-TZP zirconia cylinder specimens (IPS e.max ZirCAD, Ivoclar vivadent) will be fabricated and sintered in high temperature furnace of (1500 C for 8 hours) according to manufacturer’s instructions to the selected size and shape of (5mm. in diameter and 6mm in height). All specimens were ground flat using 600.800.1000.1200, aluminum oxide abrasive paper to obtain a standardized surface roughness. Surface roughness values were then recorded in µm using surface roughness tester (profilometer) to obtain a standardized data base line for all samples. The specimens were then randomly divided into three main groups (n=20); group A: no surface treatment (control group), group B: specimens in this group treated with 50μm Al2O3 and group C: specimens in this group treated with Er,Cr:YSGG laser. Sixty sound human premolars were used in this study, after construction of acrylic blocks, the occlusal surface of the teeth were ground flat, with diamond cutting disk to obtain a flat dentine surface . Prior to cementation of zirconia cylinders to tooth specimens subgroups (A1,B1,C1) will receive a coat of metal/zirconia primer and left to react for three minutes, while the subgroups (A2,B2,C2) were left undisturbed. Bonding surface of zirconia cylinder was then luted with SpeedCEM self adhesive resin cement under a static load of 2Kg. placed on the vertical arm of the surveyor and allowed to auto cure for 4minutes.The final cemented specimens were then stored in distilled water at room temperature for 24hours. All specimens were subjected to shear loading force in a universal testing machine at crosshead speed of 1mm/min. The shear bond strength values were analyzed statistically with one-way ANOVA; the fractured surfaces of zirconia cylinders were examined with a stereo-microscope to observe the failure mode. Results: The air borne-particle of 50μm followed by primer application showed significantly the higher bond strength than other groups. Conclusion : Within the limitation of this study, the results showed that sandblasting the bonding surface of zirconium cylinders with 50μmAl2O3 produced the highest values of shear bond strength , also the use of primer enhanced shear bond strength as well. Keyword: zirconia surface treatments, shear bond strength.
Background: Chemokine (C-X-C motif) ligand (CXCL9) has an important role recruiting the T-lymphocytes and immune response after infection by inducing T-cells accumulation around the areas associated with infections. However, this role is poorly known in relation with Toxoplasma gondii infection and also in association with thyroid hormones, which the present study is focused on. Methods: Eighty-seven women were included in this study for the period between September 2021 and February 2022. Blood samples of uninfected healthy pregnant, in addition to aborted and pregnant women infected with toxoplasmosis, were collected. Sera were then obtained and stored at -10°C. Toxo-latex agglutination test was done, followed by detec
... Show MoreThe topic of the research dealt with the image of Iraq in the British press based on a sample of the newspapers (The Guardian and the Daily Telegraph), which are among the most important and largest newspapers in the United Kingdom and the world, because of its active role in guiding local and international public opinion towards important issues and events, Since these two newspapers are interested in the accuracy of sensitive political topics, the message aimed at knowing the media image that these two newspapers painted about Iraq in the period that was limited to the first quarter of 2019, and also to know the nature of the contents promoted by these newspapers about the Iraqi reality, The method of content analysis was used as an ap
... Show MoreThe adsorption ability of Iraqi initiated calcined granulated montmorillonite to adsorb Symmetrical Schiff Base Ligand 4,4’-[hydrazine-1, 2-diylidenebis (methan-1-yl-1-ylidene)) bis (2-methoxyphenol)] derived from condensation reaction of hydrazine hydrate and 4-hydroxy-3-methoxybenzaldehyde, from aqueous solutions has been investigated through columnar method.The ligand (H2L) adsorption found to be dependent on adsorbent dosage, initial concentration and contact time.All columnar experiments were carried out at three different pH values (5.5, 7and 8) using buffer solutions at flow rate of (3 drops/ min.),at room temperature (25±2)°C. The experimental isotherm data were analyzed using Langmuir, Freundlich and Temkin equations. The monol
... Show MoreThe developed financial system is essential for increasing economic growth and poverty reduction in the world. The financial development helps in poverty reduction indirectly via intermediate channel which is the economic growth. The financial development enhancing economic development through mobilization of savings and channel them to the most efficient uses with higher economic and social returns. In addition, the economic growth reduces the poverty through two channels. The first is direct by increasing the introduction factors held by poor and improve the situations into the sectors and areas where the poor live. The second is indirect through redistribution the realized incomes from the economic growth as well as the realiz
... Show MoreThe study has tackled three important variables on the strategic and organizational level, that are : (Administrative skill, strategic Entrepreneurship and organizational flexibility). Through the statistical analysis is, the research hers have sought to identify the relation among them. The study has been applied on a sample of (44) private banks in Iraq. A questionnaire, which has been designed according to a number of international standards, has been used. It's made of (29) items that cover the three variables to test their hypotheses. A number of statistical tools have been used A number of conclusion have been reached and recommendations have also been suggested.
Praise be to God, Lord of the Worlds, and prayers and peace be upon the Master of Messengers and his family and companions.
The study of the jurisprudential opinions of scholars, their choices, or their weightings, sheds light on the approach they followed in their choices, and reveals the originality of the scholar or his influence on those who preceded him from among the scholars.
And the commentators of the noble hadith of the Prophet have their important contributions in this aspect, as they undertake the task of explaining the noble hadith, the second source of legislation
Contemporary commentators have their share in the service of the honorable hadith, and the statement of their choices and preferences, and am
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Green biosynthesized selenium nanoparticles from
Our study comes up to clarify the role of television in spreading the culture of violence with a child. This study represents one of the important studies that have tried to highlight the impact of these programmes, particularly cartoons, on the child's behaviors, actions and acquired habits.Violence considers a common phenomenon among the people, as the role of the media, particularly TV has a vital role due to its properties, characteristics and its significant impact on different segments and groups in society and in children particularly through exposure to programmes of films.The results of the study have been affected by the rising proportion of females to males, and that the contribution of real life has a big role in the child ac
... Show MoreRehabilitation robots are widely recognized as vital for restoring motor function in patients with lower-limb impairments. A Modified Fractional-Order Proportional-Integral-Derivative (MFOPID) controller is proposed to improve trajectory tracking of a 2-DoF Lower Limb Rehabilitation Exoskeleton Robot (LLRER). The classical FOPID is augmented with a modified control formulation by which steady-state error is reduced and the transient response is sharpened. Controller gains and fractional orders were tuned offline using a hybrid metaheuristic Improved Elk Herd Optimization hybridized with Grey Wolf and Multi-Verse Optimization algorithms (IElk-GM) so that exploration and exploitation are balanced. Superiority over the classical FOPID
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