Background: Radiopacity is one of the prerequisites for dental materials, especially for composite restorations. It's essential for easy detection of secondary dental caries as well as observation of the radiographic interface between the materials and tooth structure. The aim of this study to assess the difference in radiopacity of different resin composites using a digital x-ray system. Materials and methods: Ten specimens (6mm diameter and 1mm thickness) of three types of composite resins (Evetric, Estelite Sigma Quick,and G-aenial) were fabricated using Teflon mold. The radiopacity was assessed using dental radiography equipment in combination with a phosphor plate digital system and a grey scale value aluminum step wedge with thickness varying from 1mm to 10mm in steps of 1mm each. The tested materials were radiographed, we used Image J software, on a computer screen to evaluate the degree of radiopacity for each individual material and compare with the aluminum step wedge. Radiopacity was expressed in mm of equivalent aluminum step wedge. Analysis of varience (ANOVA) and Least Significant Difference (LSD) were used to investigate the significance of differences among the tested groups. Results: Statistical analysis showed highly significant difference among the tested groups (p≤0.01). Amongst, G-aenial composite shows the most radiopaque and it is above or equivalent to that of enamel, while Estelite Sigma Quick composite has the lowest radiopacity value and is equivalent to that of dentin. Conclusion: In line with previous studies, and within the limitation of our study, considerable variations in radiopacity values were found among materials depending on the radiopaque elements incorporated into the matrix. All composite materials tested complied with the ISO 4049 standard.
Shmuel Yosef Agnon, a well-known Jewish writer, wrote many literary works, including poetry, story, etc. In the field of story, this writer used two areas: the first: a simple exterior, and the second: an inner full of secrets and mysteries. This area is common when Agnon is affected by his symbolic method of purpose. In his productions, we find the political and historical significance embodied in his characters, where there is almost no story without it.
Agnon and all his productions gave the character a large area, Agnon’s characters often play the center and cornerstone in those productions, where the author dealt deeply and stated the fines details of the external and internal of that ch
... Show MoreThe article describes a study on the role of vitamin C as a protective agent for the teeth, gum, and implants using quantum chemical calculations and polarization tests. The Density Functional Theory (DFT) at 6-311G (d, p) basis set is used to estimate the ability of vitamin C to inhibit the corrosion of the abovementioned parts. The experimental study was performed in a at human body media simulator (Hank’s balanced salt solution) at a temperature of 37°C. The compound was optimized for its ground state, physical properties, and corrosion parameters. Further, HOMO, LUMO, energy gap, dipole moment, and other parameters were used to predict the inhibitor’s efficiency. Gaussian 09, UCA-FUKUI, MGL tools, DSV, and LigPlus software was used
... Show MoreWorld statistics proved that the most of work dangerous accidents, which causes death, are occurred in the construction works. These accidents related to many causes such as loss of workers experience and ignoring rules of safety requirements, especially young workers. Due to the risk of accidents that may occur in the site of work, the idea of this study crystallized to show the relationship between the age of worker and number of injuries and accidents, to identify the causes of these injuries, and to put the appropriate solutions to avoid or reduce the risk of work injuries. Also, the research shows the main principles of safety requirements to forming a clear picture about the subject of the study. A questioner form was prepared to c
... Show MoreThe research aims to know the impact of the innovative matrix strategy and the problem tree strategy in teaching mathematics to intermediate grade female students on mathematical proficiency. To achieve the research objectives, an experimental approach and a quasi-experimental design were used for two equivalent experimental groups. The first is studied according to the innovative matrix strategy, the second group is studied according to the problem tree strategy. The research sample consisted of (32) female students of the first intermediate grade, who were intentionally chosen after ensuring their equivalence, taking into several factors, most notably (chronological age, previous achievement, and intelligence test). The research tools con
... Show MoreHR Ghanim, GA Abdulhassan, International Journal of Early Childhood Special Education, 2022
The aim of the research is to diagnose the methods of enhancing the value of citizenship in children through the interactive life process in educational institutions; the descriptive approach was used to achieve the objective by identifying social theories that corresponded to the national value or the theoretical principles of citizenship education. The study focused on educational activities and their role in establishing values, national educational philosophy in interactive activities, as well as the presentation of previous studies on the subject of citizenship, and maps of each of the strategies of active learning, skills in the process of interactive life in the field of education, Institutions that have the responsibility to prom
... Show MoreThe study aims to highlighting the Creative Accounting practices, identifying their impact on non reliability of financial statement of Insurance companies and Iraqi Public Reinsurance Company. Certain executive managements resort to creative accounting to falsely portray a better image to financial statement users by means of a set of techniques and mechanisms. Thus, impacting the company activities, The study was carried out in state insurance companies and Iraqi Public Reinsurance Company. Miller model is adopted to measure earning management practices. It is one of the tools to detect creative accounting practices and to measure reliability of accounting information of financial statements by applying “White” scale on
... Show MoreThe research aims at measuring the extent of the relationship and influence of the indicators of the Core competencies of the audit firms and offices in the Earning Quality of the private banks listed in the Iraq Stock Exchange under audit. The research community represents 38 banks. The sample of the research has been approved only 10 banks continue to issue their financial statements for the period (2007 – 2017), in addition to the audit offices assigned to audit these banks, which amounted to 14 companies and auditing offices. John's (1999) model revised by Kothari et al., (2005) was adopted to measure the Earning Quality by finding discretionary accruals and non-discretionary accruals, to measure the Core competencies indicators ,
... Show MoreMany nations are seeing an increase in water pollution from dairy and cheese production due to the high organic and fat content in their waste products and the high temperature of their waste products, which elevates the water temperature and causes loss to ecosystem components. Reusing industrial wastewater that has been treated to guarantee no harm has been done to the environment is being hampered by a lack of water. This study compares the presence and absence of mixing in the anaerobic biological treatment of liquid waste for the cheese industry. To decrease heat exchange with the external environment, cube-shaped anaerobic reactors with dimensions of (30 x 30 x 30) cm and thick glass (10 mm) were utilized in this investigation
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