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.
In this work, (ZnO)1-x(MnO2)x compounds were synthesized with composition (x=0, 0.1, 0.2, 0.3, 0.4, and 0.5) of manganese oxide content using solid state reaction. Thin films were prepared from these compounds on glass substrates at room temperature using pulsed laser deposition method. The structure of the prepared compounds and thin films were analyzed using x-ray diffraction while the optical properties was measured using UV-visible spectrophotometry. It was found that the synthesized composites declared many peaks in the diffraction pattern which indicate polycrystalline structure with hexagonal wurtzite hexagonal structure of ZnO, and MnO2 and Mn2O3 secondary phases. A narrowing in the optical e
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A Mini-TEA CO2 laser system was designed and operated to obtain a pulse at 10.6 μm. Output energy of 30 mJ, with preionization pins, and pulse duration of 100ns were obtained. While an output energy of 6mJ and pulse duration of 100 ns in absence of pre-ionization were obtained. The system was operated with Ernest profile main-discharge electrodes. Dependencies of supply voltage and output laser energy on the pressure inside laser cavity were investigated as well as dependencies of supply voltage and output energy on the main capacitor(8CO2 : 8N2 : 82He :2CO). Efficiency of was calculated to be 4.4%.
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Secnidazole was linked with ciprofloxacin as mutual prodrugs to get antibiotics with broader spectrum of activity, improved physicochemical properties and given by single dose to improve patient’s compliance. Furthermore, they provide structural modifications to overcome bacterial adaptation. The structures of the synthesized compounds were confirmed using FT-IR, mass spectrometry, elemental microanalysis (CHNO) and some physiochemical properties. This modification was led to an increase in Log P values for Mutual I (Log P 1.114) and Mutual II (Log P 1.97) compared with its values for Secnidazole (Log P -0.373) and ciprofloxacin (Log P -0.832). The solubility of prodrugs had been determined in different media, Mutual II showed 1
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A nonlinear filter for smoothing color and gray images
corrupted by Gaussian noise is presented in this paper. The proposed
filter designed to reduce the noise in the R,G, and B bands of the
color images and preserving the edges. This filter applied in order to
prepare images for further processing such as edge detection and
image segmentation.
The results of computer simulations show that the proposed
filter gave satisfactory results when compared with the results of
conventional filters such as Gaussian low pass filter and median filter
by using Cross Correlation Coefficient (ccc) criteria.
The purpose of this research is to investigate the impact of corrosive environment (corrosive ferric chloride of 1, 2, 5, 6% wt. at room temperature), immersion period of (48, 72, 96, 120, 144 hours), and surface roughness on pitting corrosion characteristics and use the data to build an artificial neural network and test its ability to predict the depth and intensity of pitting corrosion in a variety of conditions. Pit density and depth were calculated using a pitting corrosion test on carbon steel (C-4130). Pitting corrosion experimental tests were used to develop artificial neural network (ANN) models for predicting pitting corrosion characteristics. It was found that artificial neural network models were shown to be
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Contents IJPAM: Volume 116, No. 3 (2017)
Arthropod-borne infections, known as vector-borne diseases, are a significant threat to both humans and animals. These diseases are transmitted to humans and animals through the bites of infected arthropods. In the last half century, there have been a number of unexpected viral outbreaks in Middle Eastern countries. Recently, Iraq has witnessed an outbreak of the Crimean-Congo Hemorrhagic Fever virus with high morbidity and mortality rates in humans. However, very little is known about the prevalence and distribution of CCHFV in Iraq, and therefore, it is impossible to quantify the risk of infection. CCHFV is transmitted to humans through the bite of infected ticks. However, transmission can also occur through contact with the blood or ti
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