Objectives: Successful endodontic treatment outcome requires effective shaping and cleaning of root canals. This study aims to evaluate the smear layer removal after continuous chelation (CC) ) NaOCL\HEDP( and sequential chelation (SC) )NaOCL\EDTA( and their influence on the push-out bond strength (POBS) of Bio-C sealer. Materials and Methods: Palatal roots of the maxillary first molar (n=72) were divided into four groups (n=18) as follows: 3% NaOCL, SC: 3% NaOCL followed by 17% EDTA, CC: 3% NaOCL \9% HEDP and Distilled water. Thirty-two roots (n=8/group) were split longitudinally for smear layer evaluation using SEM. Forty roots were obturated with Guttapercha and Bio-C sealer using a single cone technique. Three sections were taken horizontally from the coronal, middle, and apical third (1.5±0.1 mm thickness) for the push-out test using a universal testing machine. The Kruskal-Wallis and Mann-Whitney tests were used to analyze the SEM data, while the One-way analysis of variance (ANOVA) test and the Tukey test were used to analyze POBS data. Z test to compare failure mode. Results: There was no difference between SC and CC in the smear layer removal at all thirds (p>0.05). The POBS in CC was significantly higher than SC in all thirds (p
— In light of the pandemic that has swept the world, the use of e-learning in educational institutions has become an urgent necessity for continued knowledge communication with students. Educational institutions can benefit from the free tools that Google provide and from these applications, Google classroom which is characterized by ease of use, but the efficiency of using Google classroom is affected by several variables not studied in previous studies Clearly, this study aimed to identify the use of Google classroom as a system for managing e-learning and the factors affecting the performance of students and lecturer. The data of this study were collected from 219 members of the faculty and students at the College of Administra
... Show MoreIn this study, SnO2 nanoparticles were prepared from cost-low tin chloride (SnCl2.2H2O) and ethanol by adding ammonia solution by the sol-gel method, which is one of the lowest-cost and simplest techniques. The SnO2 nanoparticles were dried in a drying oven at a temperature of 70°C for 7 hours. After that, it burned in an oven at a temperature of 200°C for 24 hours. The structure, material, morphological, and optical properties of the synthesized SnO2 in nanoparticle sizes are studied utilizing X-ray diffraction. The Scherrer expression was used to compute nanoparticle sizes according to X-ray diffraction, and the results needed to be scrutinized more closely. The micro-strain indicates the broadening of diffraction peaks for nano
... Show MoreThe study aims to identify the degree of implementation of the coronavirus prevention standards (covid-19) in the kingdom of Saudi Arabia and compare it with the families of intellectual disabilities. The study population consisted of all families residing in the Kingdom of Saudi Arabia. To achieve the objectives of the research, the analytical descriptive approach was employed. The study sample consisted of (372) families, among them (84) families with intellectual disabilities, and (288) families without intellectual disabilities. They were chosen from the Saudi community according to what is available for collection in a simple random way, using the standard criteria for the prevention of coronavirus (Covid- 19) Prepared by the resear
... Show MoreSilver nanoparticles synthesized by different species
he study aims to build a model that revolves around the main question of the role of strategic agility (SA) in enhancing organizational excellence (OE). For the purpose of achieving OE and to determine the extent of interest and knowledge of managers at the Midwest Refineries Company (MRC) on the theoretical and practical implications, and on the performance foundations of these two vital variables with the aim of continuous improvement. A questionnaire was used and distributed to a random sample of 54 managers in this important energy production company. The study followed the descriptive analytical approach to answer the questions raised. The study model and dimensions were built according to reference models, most notably the models (Al-
... Show MoreRapid and continuous developments and changes in the modern business environment in all areas of economic, environmental, social, technology and communications push economic units to search for modern methods and methodologies to produce products at low cost as well as produce products that meet the wishes of customers in terms of quality and environment to maintain their market position, and accounting for the costs of the flow of materials is one of the most prominent environmental management accounting techniques capable of providing information to help produce