Background: Apicoectomy and retrograde filling is indicated when conventional endodontic treatment is impossible or failed to achieve apical seal. The aim of this study was to evaluate the effect of ER: YAG laser on apical microleakage. Materials and Methods: Sixty extracted single-rooted teeth were used in this study. The roots were divided into six groups. Group 1: apicoectomy by fissure bur, and apical cavities prepared by round bur, then cavities were filled with MTA. Group 2: the roots preparations and fillings were the same as group 1, then the apical areas were treated by Er:YAG Laser. Group 3: apicoectomy by fissure bur, and apical cavities prepared by ultrasound retrotip and cavities were filled with MTA. Group 4: the roots preparations and fillings were the same as group 3, then the apical areas were treated by Er:YAG Laser. Group 5: the roots obturation with gutta percha, then the apices were resected using Er:YAG Laser. Group 6: the roots apices were resected with Er:YAG Laser, then the canals were obturates with gutta percha. Apical microleakage was measured by methylene blue dye penetration technique. Results: Significant difference between the groups. Group 1 shows the best apical seal, while group 5 shows the worse apical sealing ability. Conclusion: Apicoectomy by bur is better than apicoectomy by laser, and apical cavity prepared by bur is better than prepared by US. The use of ER: YAG laser in apicoectomy is preferred to be done before obturation of the root canal with gutta percha.
The electoral poster is the most important means and methods of the electoral campaign because of its advantages and capabilities if it is organized properly. It is an intensive propaganda message with psychological figures and semiotic connotations belonging to sub-culture. Its construction depends on a group of elements (logo, photo symbols, color and picture) and their consistency is varying from one to another. Posters must be committed the determinants of attraction, excitement, simplicity and clarity. They are working according to the following base: (fixed audience X moved recipients) and walking towards (moving X moving) due to the technical development of optical screens. These developments require double the force of the impact
... Show MoreThe strategies of knowledge management have became the basis in the promotion of core competencies. Therefore gained an increasing prominence. This led the administrations of organizations to work to effectiveness of there strategies, which results to build there core competences through teamwork, empowerment and personal effectiveness of employees. From this arises research problem about the organizations leaders recognize extent of knowledge management strategies which that lead to core competence. In addition the research tray definition the relation and nature of affect between its variables. The research was carried on sample (72) managers from board of supreme audit in Iraq and used statistical tools and methods.
... Show MoreThe aim of the research is to use this technique and to determine the effect of this method in reduce cost per unit of the company. The traditional method used in the company the research sample to determine the indirect costs, the definition of the concepts and characteristics of the method of cost-based activity and the cost method based on time-driven activity and justifications applied to companies. In order to achieve the research objectives, the main hypotheses were formulated. That was represented: (The applied of (TDABC) Time driven activity based costing method in reducing indirect costs, leads reduce cost per unit than the use of the traditional method of allocating indirect costs in the research sample company).&nb
... Show MoreThis research aims to numerous risks to the portfolio of the insurance company that arise from practicing the activity in general, and the risks arising from insurance contracts in particular, and what is the role of the company in the disclosure to help users (such as owners) to understand and concentration of risks in the financial reporting and identifying movable risks size to reinsurers that may affect the solvency of the portfolio and makes them at a given moment required to fulfill the obligations towards policyholders outweigh the financial capacity, which leads to stumble or bankruptcy.
So I sought this research is to identify the extent of the obligation to disclose the accounting for this risk and the extent of their i
... Show MoreThe research aims to determine the factors affecting the woman’s use of electronic marketing in social networking sites, and to know the extent of the sample’s use of social networking sites for electronic shopping purposes. The research tool used the questionnaire form that was designed in its final form after presenting it to the arbitrators and it included a set of questions and a five-Likert scale, and used the spss statistical program to perform the statistical operations that were laid out in tables showing the frequencies, percentages and percentages Salary, mean, standard deviation, and correlation using the Spearman correlation coefficient, the Ka2 square test, the F test, the Alpha Cronbach test, and arrived at Searching to
... Show MoreThis study reveals the results of a numerical simulation performed using the ABAQUS/CAE finite element program. The study aimed to provide a simulation model that can forecast the shear behavior of reinforced concrete beams confined with reinforcing meshes. Limited numerical studies have been conducted using geogrid or FRP mesh as shear reinforcement, with limited representation accuracy and limited material quality. The results were compared to published experimental findings in the literature. The finding of the finite element model and the experimental results were highly comparable; consequently, the model was determined to be valid. Following this, the domain of numerical analyses was broadened to include the investigation of m
... Show MoreThermal performance of closed wet cooling tower has been investigated experimentally and theoretically
in this work. The theoretical model based on heat and mass transfer equations and heat and mass transfer balance equations which are established for steady state case. A new small indirect cooling tower was used for conducting experiments. The cooling capacity of cooling tower is 1 kW for an inlet water temperature of 38oC, a water mass velocity 2.3 kg/m2.s and an air wet bulb temperature of 26oC. This study investigates the relationship between saturation efficiency, cooling capacity and coefficient of performance of closed wet cooling tower versus different operating parameters such wet-bulb temperature, variable air-spray water fl
Objective: The current study aimed to prepare a measure for comprehensive knowledge marketing management. In the Iraqi sports institutions under study, identifying the extent of each dimension of comprehensive knowledge marketing management. Research methodology: This study relied on appropriate scientific methods, mainly represented by the descriptive method and the analytical method, and on the case study method because it suits the nature of the study. The study population was determined from the administrative cadres in the Iraqi Sports Federation, and the research sample numbered (86) and was represented as follows: The preparation sample numbered (50) and a percentage amounted to (58.13%), the sample of the exploratory experim
... Show MoreThe aim of the research is to determine the extent to which young people watch television sports programs and the impact of viewing on the level of sports culture among young people and the impact of demographic variables on youth over the viewing of sports programs, The study was conducted on a sample of (200) male and female students from the faculties of the University of Baghdad, where a questionnaire form composed of several axes and questions was prepared to measure the effectiveness of sports programs in youth culture, The statistical program used spss to empty data and extract results by frequency, percentages, correlations, The research reached several results, the most important of which is that there is a strong influence of s
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