Background: Restoration of root canal treated teeth with a permanent restoration affect in the success of endodontically treated teeth. This in vitro study was performed to evaluate and compare the fracture strength of endodontically treated teeth restored by using custom made zirconium posts and cores, prefabricated carbon fiber, glass fiber and zirconium ceramic posts. Materials and method: Forty intact human mandibular second premolars were collected for this study and were divided into five groups. Each group contains 8 specimens: Group1: Teeth restored with Carbon Fiber Posts; Group2: Teeth restored with Glass Fiber Posts; Group3: Teeth restored with Zirconium Ceramic prefabricated Posts; Group4: Teeth restored with Zirconium Posts and Cores (copy milling); Group5: (Control Group).For groups 1, 2, 3, and 4; crowns were removed horizontally at the level of cement-enamel junction. Endodontic therapy was then done for all specimens in these groups using step-back technique.These specimens received standardized posts preparation (10mm depth), and then mounted in acrylic resin blocks. Panavia F 2.0 dual cure resin cement was used for cementation. The core build up was done with composite (Filtek P60). The specimens were then stored in saline and were subjected to compressive loads parallel to their long axes using universal testing machine (WP 300) until failure. Results: Data obtained were analyzed by one-way analysis of varianceand student t-test. The results showed that zirconium posts and cores possessed the highest significant differences followed by glass fiber posts, carbon fiber posts, and prefabricated ceramic zirconium posts. There were no significant differences between glass fiber, carbon fiber, and control group. The specimens were examined to determine the root fracture patterns and locations. Conclusion: In the present study the fiber post treated teeth showed significantly more desirable fracture patterns compared to those restored with zircon posts.
Luminescent solar concentrator (LSC) are used to enhance photoresponsivity of solar cell. The Quantumdots luminescent solar concentrator (QDLSC) consists of CdSe/CdS core/shell nanoparticles embedded in polyacrylamide polymer matrix positioned on the top surface of the silicon solar cell. This procedure improves the conversion efficiency of the bare silicon solar cell. The conversion efficiency of the solar cell has increased from 7.3% to 10.3%. this improvement is referred to the widening of the response spectral region window of the a- Si. Solar cell.
(2)
This paper presents a comparative study between different oil production enhancement scenarios in the Saadi tight oil reservoir located in the Halfaya Iraqi oil field. The reservoir exhibits poor petrophysical characteristics, including medium pore size, low permeability (reaching zero in some areas), and high porosity of up to 25%. Previous stimulation techniques such as acid fracturing and matrix acidizing have yielded low oil production in this reservoir. Therefore, the feasibility of hydraulic fracturing stimulation and/or horizontal well drilling scenarios was assessed to increase the production rate. While horizontal drilling and hydraulic fracturing can improve well performance, they come with high costs, often accounting for up t
... Show More
Abstract
Objectives: To assess patients’ knowledge and their adherence to Clopidogrel Therapy Post Percutaneous Coronary Intervention, and to find out the relationship between patients’ knowledge and their adherence to Clopidogrel Therapy Post Percutaneous Coronary Intervention
Methodology: A descriptive design was carried out at Al- Nasiriyah Heart Center in Thi-Qar Governorate for the period between May 19th, 2022 to October 25th, 2022. A non-probability sampling was used among (50) patients after their Percutaneous Coronary Intervention. The study instrument that used to collect data was composed of three parts namely: sociodemographic charac
... Show More
(1)
Abstract This study aims to compare British war poetry of the First World War with Iraqi poetry from the mid-20th century with special reference to Iraqi war poetry of the 1980’s Iraq-Iran War and the period that followed it. It will also investigate the influence of the designated British war poetry on the chosen body of Iraqi poetry. Through the comparison of sample poems the study presents, firstly, the direct influence of the British poetry of the Great War and its translation which formed the seeds of a more radical movement in Iraqi poetry during the 1980’s Iran/Iraq War and the period that followed it. The study also presents a comparison of the works of British and Iraqi civilian poets during and after the war time and their con
... Show MoreBackground: Studying and investigating the transverse strength(Ts), impact strength(Is), hardness (Hr) and surface roughness(Ra) of conventional and modified autopolymerizing acrylic resin with different weight percentages of biopolymer kraftlignin, after curing in different water temperatures; 40°C and 80°C. Material and Methods: Standard acrylic specimens were fabricated according to ADA specification No.12 for transverse strength, ISO 179 was used for impact testing, Shore D for hardness and profilometerfor surface roughness. The material lignin first dispersed in the monomer, then the powder PMMA is immediately added. Ligninadded in different weight percentages. Then cured using pressure pot (Ivomet) in two temperatures;40°C a
... Show MoreBackground: The aim of this study was to comparatively evaluate the push out bond strength (PBS) of root canal fillings using four different obturation techniques (single cone (SC), cold lateral compaction (CLC), continuous wave (CW), and carrier based gutta percha (CBG)). Materials and Methods: Forty mandibular premolar decoronated and instrumented with rotary ProTaper to F3 then teeth were divided randomly into 4 groups of 10 teeth for each as follow: group (I) single- cone obturation with matched-taper gutta-percha, group (II) cold lateral compaction technique, group (III) continuous wave of obturation technique, and group( IV) carrier based gutta-percha technique. Zinc oxide eugenol (ZOE) sealer was used as a root canal sealer for the
... Show MoreBackground: Denture relining is the process of resurfacing of the tissue side of the ill fitting denture, the bond strength at the relining-denture base interface is most important for denture durability.The aim of present study was to evaluate the shear bond strength between the thermosens as relining material and different denture base materials that bonded by thermo fusing liquid. As this corrective procedureis the common chair side procedure in the dental clinic. Material and method: Sixty samples were prepared and divided into three main groups according to the type of denture base materials.Group (A) referred to the heat cure acrylic samples which consisted of 20 samples. Group (B) referred to the high impact acrylic samples which con
... Show MoreA confluence of forces has brought journalism and journalism education to a precipice. The rise of fascism, the advance of digital technology, and the erosion of the economic foundation of news media are disrupting journalism and mass communication (JMC) around the world. Combined with the increasingly globalized nature of journalism and media, these forces are posing extraordinary challenges to and opportunities for journalism and media education. This essay outlines 10 core principles to guide and reinvigorate international JMC education. We offer a concluding principle for JMC education as a foundation for the general education of college students.
The study aimed at the following:
Identify the differences in average scores core thinking skills kindergarten children by variable sex (male - female), and by variable age (5.6 - 5.11).
To achieve this researcher adopted a standardized test of core thinking skills for the kindergarten children, which was built and standardization by the researcher Meyada Asaad Mussa 2012 . applied test on a sample of (814) ) boys and girls who were randomly chosen form, from directorates of Baghdad Education Adoption of the proportional distribution.
... Show More