Background: The displacement of artificial teeth during complete denture construction presents major processing errors in the occlusal vertical dimension which were verified at the previous trial denture stage. The aim of this study was to assess the effect of delay in processing after final flask closure and tension application on the vertical acrylic and porcelain teeth displacement of complete dentures constructed from heat cured acrylic and the results were compared with the conventional processing method. Materials and methods: forty samples of identical maxillary complete dentures were constructed from heat polymerized acrylic resin. These samples were subdivided into the following experimental subgroups in which each subgroup contains 5 samples for both acrylic and porcelain teeth and as follows: 1. Conventional flasking technique and immediate processing. 2. Conventional flasking technique and 6 hours delay in processing. 3. flasking technique with tension system and immediate processing. 4. flasking technique with tension system and 6 hours delay in processing. Reference metal pins were attached to the middle of the buccal surface of the upper right canine and center of the buccal groove of the left first molar. And according to these reference points on the teeth another metallic Reference pins were fixed on the denture vestibules and at a distance of 7.5mm by straight lines and 6.5mm where placed between the metal pins and the vestibules in order to standardize the measurement. The distance between the right and left metal pins on the canine and molars and the corresponding metal pins on the buccal vestibules were measured during the wax up stage and after processing by using an optical travelling microscope with an accuracy of 0.0005 mm. Means in (mm) were analyzed statistically by analysis of variance and the comparative T-test and least significance test (LSD). Results: Significant reduction in vertical displacement of the teeth occurred in groups when 6 hours delay in processing were applied, but a significant improvement was also observed in groups with tension system application when compared with control group. On the other hand, there were a high significant reduction in the vertical displacement in groups with tension system and 6 hours delay in processing combination. While for the type of artificial teeth data showed significant difference in the amount of vertical displacement of the teeth in groups with acrylic teeth when compared with porcelain teeth. Conclusions: The findings of this study showed that 6 hours delay in processing and tension system application were effective in reducing the vertical displacement of the artificial teeth during flasking. The maximum reduction in the displacement was observed in dentures constructed from acrylic teeth. On the other hand, significant decrease in vertical displacement of the teeth was detected in dentures constructed from porcelain teeth.
This study examines the vibrations produced by hydropower operations to improve embankment dam safety. This study consists of two parts: In the first part, ANSYS-CFX was used to generate a three-dimensional (3-D) finite volume (FV) model to simulate a vertical Francis turbine unit in the Mosul hydropower plant. The pressure pattern result of the turbine model was transformed into the dam body to show how the turbine unit's operation affects the dam's stability. The upstream reservoir conditions, various flow rates, and fully open inlet gates were considered. In the second part of this study, a 3-D FE Mosul dam model was simulated using an ANSYS program. The operational turbine model's water pressure pattern is conveyed t
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شهدت العالم منذ نهايات القرن الماضي وبدايات القرن الواحد والعشرين تطورات دراماتيكية على صعيد الادبيات التنموية ، اذ تحولت التنمية من المفهوم التقليدي الذي اهتم بالنمو الاقتصادي الى رؤية جديدة هي رؤية التنمية البشرية ومن ثم الى التنمية المستدامة التي اعطت للتنمية البعد الانساني وجعلت من مشكلات واحتياجات البشر منطلق لها لتحويل الفرد والمجتمع الى مرحلة جديدة تضمن له العيش الكريم وتحقق معه
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The research deals with the important and modern two subject (career path and the type of training program), and tries to find identify the extent of the impact of the requirements of a career path in determining the type of training program in the Ministry of Oil.
In order to achieve the aim of the research was the formulation of the following hypothesis: the impact of the requirements of the career path a meaningful moral influence in determining the type of training program.
The survey was adopted in the search, and sample consisted of (75) people were a factor in the Oil Ministry of People's managers and officials and staff, and used the questionnaire as an es
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The aim of this study is to make the inventory for Umbelliferae family for the purpose of identifying the samples that were collected over long periods and saved in the herbarium of Iraq Natural History Museum/ University of Baghdad. We found that the herbarium plants were very large and varied from different parts for Iraq, in different and varied environments, which collected and arranged according to a very specific system in the herbarium for remaining an important source to all graduate students and researchers to take advantage for these plants. Also, the flowering and fruiting periods for these plants in Iraq were recorded in different regions. Most these plants begin to flower in the spring and thrive at fields and farms.
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The research specializes in (Usage of the visual elements in the interior designing of indoor swimming pools), the research seeks to provide a study that contributes to providing scientific and knowledge material, as a reference for researchers, students of interior design and architecture, and companies constructing indoor swimming pools.
The objective research is to detect the actual state of the interior design of the indoor swimming pools, and recognize the most important standards and techniques used in its design to provide appropriate design solutions if needed also Proposing a development proposals for the interior design of indoor swimming pools, the theoretical framework of this study, included two sections, The first one ta
Man was closely associated with nature in its various forms, as it represented the incubator for him in all areas of his life, so writers often made it a material for their literature and a fertile ground for their productions, so it appeared in its various forms and man’s need for it, its good and its bad in literature throughout history, and the Arabs are like Other nations, since the pre-Islamic era, nature was an important outlet and a refuge for poets in the production and creativity of literature and to this day, and when we talk about a poet from the Fatimid state, we find that nature - especially spring and its flowers - in that period took its take from literature and represented a phenomenon for many Among the
... Show MoreIn this research, non-thermal plasma system of argon gas is designed to work at normal atmospheric pressure and suitable for work in medical and biotechnological applications. This technique is applied in the treatment of the Staphylococcus epidermidis bacteria and show the role of the flow rate of Argon gas on the killing rate of bacteria, and it obtained a 100 % killing rate during the time of 5 minutes at the flow Argon gas of 5 liters/ min.
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