Purpose: Despite the high clinical accuracy of dynamic navigation, inherent sources of error exist. The purpose of this study was to improve the accuracy of dynamic navigated surgical procedures in the edentulous maxilla by identifying the optimal configuration of intra-oral points that results in the lowest possible registration error for direct clinical implementation. Materials and methods: Six different 4-area configurations were tested by 3 operators against positive and negative controls (8-areas and 3-areas, respectively) using a skull model. The two dynamic navigation systems (X-Guide® and NaviDent®) and the two registration methods (bone surface tracing and fiducial markers) produced four registration groups. The accuracy of the registration was checked at the frontal process of the zygoma. Intra- and inter- operator reliability for each registration group were reported. Multiple comparisons were conducted to find the best configuration with the minimum registration error. Results: Ranking revealed one configuration in the tracing groups (Conf.3) and two configurations in the fiducial groups (Conf.3 and Conf.5) that had the best accuracy. When the inferior surfaces of the zygomatic buttress were excluded, fiducial registration produced better accuracy with both systems (p 0.006 and <0.0001). However, tracing 1 cm areas at these surfaces bilaterally resulted in similar registration accuracy as placing fiducial markers there (p 0.430 and 0.237). NaviDent® performed generally better (p 0.049, 0.001 and 0.002) albeit having a wider margin of uncertainty in the obtained values. Changing the distribution of the 4 tracing areas or fiducial markers had a less pronounced effect with X-Guide® than with the NaviDent® system. Conclusion: For edentulous maxillary surgeries, 4 fiducial markers placed according to configuration 3 or 5 result in the lowest registration error. Where implants are being placed bilaterally, an additional 2 sites may reduce the error further. For bilateral zygomatic implant placement, it is optimal to place 2 fiducials on the inferior surfaces of the maxillary tuberosities, other 2 on their buccal surfaces, and 2 on the anterior labial surface of the alveolar bone. Utilising the inferior zygomatic buttress is recommended over the inferior maxillary tuberosities in other types of maxillary surgeries.
Flexible pavement design and analysis were carried out in the past with semi-experimental methods, using elastic characteristics of pavement layers. Due to the complex interferences between various layers and their time consumption, the traditional pavement analysis, and design methods were replaced with fast and powerful methods including the Finite Element Method (FEM) and the Discrete Element Method (DEM). FEM requires less computational power and is more appropriate for continuous environments. In this study, flexible pavement consisting of 5 layers (surface, binder, base, subbase, and subgrade) had been analyzed using FEM. The ABAQUS (6.14-2) software had been utilized to investigate the influence of the base layer depth on ver
... Show MoreOne of the artificial lightweight aggregates with a wide range of applications is Lightweight Expanded Clay Aggregate. Clay is utilized in the production of light aggregates. Using leftover clay from significant infrastructure development projects to manufacture lightweight aggregates has a favorable environmental impact. This research examines the expanded clay aggregate production process and the impact of processing parameters on its physical and mechanical qualities. It also looks at secondary components that can be used to improve the qualities of concrete with expanded clay aggregates. The effect of the quantity of expanded clay aggregate on the fresh, hardened, and durability qualities of concrete is also studied.
... Show MoreA Field experiment was conducted in Horticulture and Landscape Department, College of Agricultural Engineering Sciences, University of Baghdad, Al-Jadriah during fall 2019-2020 to study changes in the growth and yield of broccoli grown in the alternative solution ABEER, affected by gas enrichment and spraying with coconut water and moringa aqueous extract under the hydroponic cultivation system. Nested design with three replications adopted in the experiment, each of them included in main plot the first factor, which is gas enrichment (O2 and O3), Then levels of second factor were randomly distributed within each replicate, which included spra
Environmental Tax is deemed as one of the most important tools that can be used to eliminate the problem of oil –based environment pollution resulted out of oil products processes and this has been significantly approved by the experience in those leading countries in the field of protecting the environment against pollution whereas oil-producing countries which are rather awkward in maintaining the environment such as Iraq , suffer from notorious environmental effects pertaining to oil product processes.
The problem of the research is represented the increased and constant rise in the volume of the environmental pollutants resulted from the processes managed by the intern
... Show MoreThe present research aims to identify and define the basic dimensions of the information management strategy and the administrative creativity in the Faculty of Management and Economics / the University of Kirkuk, as well as the role played by the dimensions of the information technology management strategy in achieving the administrative innovation in the college and the research problem was formulated in several questions. The research problem was formulated in several questions centered on the correlation between the research variables, and the research was based on a major hypothesis and five sub-hypotheses emerged from which it was subjected to several tests to ensure its validity. The researcher used the descriptive-analyti
... Show MoreA field study aimed at identifying the sources of mutual complaints among the Directorates of Education staff of their departments and management and run it in their daily dealings with principals in the province of Baghdad, and adopt approach. It was determined the research consists of (2357) male and female employees and 305 randomly stratified simple by the rate of (7%) from the research community as the number of sample reached (167) male and female employees, and selected sample was randomly stratified simple by the rate of (39.67%) of the research community, as the number of sample was (121) principals. It was constructed two questionnaires, the first included (28) items and the second contained (28) items. And the two researchers
... Show MoreThe research topic was chosen as a result of the importance of human resource in business organizations in general and the industrial process in particular. Without the human resource, business organizations cannot continue and achieve success and excellence, and the research problem has been diagnosed in the lack of sales of General Cement Company’s northern products, despite their distinctiveness, standing, and reputation in The market and its products with standard specifications, and through this problem, the following questions were raised: &nbs
... Show MoreBackground: EBV infection in tissue micro-environment is challenged by the precisely regulated survivaland apoptosis mechanisms. Abnormal bcl-2 proto-oncogene expression in colonic carcinomas allowsaccumulation and propagation of these genetically altered cells.Objective: To analyze the relevant concordance of BCL-2 gene , EBNA1 s and LMP-1-EBV expression inissues from a group of Iraqi patients with colonic adenocarcinomas.Patients and Methods: One hundred (100) tissue biopsies, belonged to (40) patients with colorectalcancers, (40) patients with benign colon tumors, and (20) apparently normal colorectal control tissues,were enrolled in this study. The detection of EBNA1 s and LMP-1-EBV as well as BCL-2 was done byimmunohistochemist
... Show MoreRole of public relations (PR) and from one community to another, depending on the different cultures of these societies in General, and different ethical values established by their practitioners in these communities organizations , public relations in developed societies, and in some developing countries have taken great strides to contribute to the strategic planning and decision-making, in the framework of their commitment to the values and ethical standards for practitioners, In contrast, we find that applied in Iraq still skips phase coordinate with different communication means with the aim of advertising and publicity for the organization. As a result of the limited recognition of the strategic and vital
... Show MoreTwo prevalent neurodevelopment disorders in children are attention deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD). The fifth version of the Diagnostic and Statistical Manual of Mental Disorders describes autism as a condition marked by limitations in social communication as well as restricted, repetitive behavior patterns. While impulsivity, hyperactivity, and lack of concentration are signs of attention deficit hyperactivity disorder. Boys experience it more frequently than girls do. This study sought for possible factors that put children at risk for autism and attention deficit hyperactivity disorder, and it investigated the association between neurodevelopment disorders in children and parental risk factor i
... Show More