Background: The purpose of this study was to verify the influence of post- pressing time of acrylic resin (immediate, 6, 12 and 24 hour) on the dimensional accuracy of denture base whish is a critical factor in the retention and stability of the complete denture that may occur during polymerization shrinkage. Materials and Methods: Forty maxillary stone casts were poured in plastic mold (Columbia Dentoform corp. NEW YORK, type III dental stone (Geastone, Zeus Sri Loc.Tamburine Roccastrada, GR, Italy). The stone casts were randomly assigned into 4 groups of 10 specimens each according to the post-pressing times into (immediate, 6, 12 and 24 h.). Heat cure acrylic resin denture base was constructed according to the previously mentioned pressing time, the resin base-stone cast sets were transversally sectioned with a manual saw device at the distal aspect of the molar area, anterior to the posterior palatal seal area. The gap between the resin base and stone cast was measured at five points in the right (point B) and left (point D) ridge crests, at the midline (point C), and at the right (point A) and left (point E) marginal limits (A), using a Leitz linear optical comparator microscope with a travelling stage capable of measuring 0.001 mm. Each measurement was repeated three times and the average was used as the linear gap distance for that point. The data were submitted to ANOVA. Result: there was statistically significant difference between the pressing time in which the mean values of gap space in point E for 24h shows lowest value then point A, point B, and point D than the other post pressing time. The mean value in point C shows highest values which mean the greater gap space in palatal area.
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This research aims to study the effect of microwave furnace heat on the mechanical properties and fatigue life of aluminum alloy (AA 2024-T3). Four conditions were used inside microwave furnace (specimens subjected to heat as dry for 30 and 60min. and specimens subjected to heat as wet (water) for 30 and 60 min.), and compared all results with original alloy (AA 2024-T3). Tensile, fatigue, hardness and surface roughness tests were used in this investigation. It is found that hardness of dry conditions is higher than wet conditions and it increases with increasing of time duration inside microwave furnace for dry and wet conditions. Also, tensile strength has the same behavior of hardness, but it increases with decreasing
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A d.c. magnetron sputtering system was designed and fabricated. The chamber of this system is consisted from two copper coaxial cylinders. The inner one used as the cathode and the outer one used as anode with magnetic coil located on the outer cylinder (anode). The axial behavior of the magnetic field strength along the cathode surface for various coil current (from 2A to 14A) are shown. The results of this work are investigated by three cylindrical Langmuir probes that have different diameters that are 2.2mm, 1mm, and 0.45mm. The results of these probes show that, there are two Maxwellian electron groups appear in the central region. As well as, the density of electron and ion decreases with increases of magnetic field strengths.
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This study examines strategies of cultural domestication in Muravyov and Kistyakovsky’s Russian translation of (The Fellowship of the Ring). It documents transformations of character names, toponyms, dialogues, and cultural references, highlighting systematic Russification and the infusion of Soviet political commentary that reshape the text into cultural rewriting.
Background: The posterior slope of the articular eminence of completely edentulous patients compared to patients with maintained occlusion shows significant flattening. This study aimed to correlate between the flattening of the posterior slope of the articular eminence, with dental status, age, genders, on both sides using computed tomography. Materials and Methods: The sample of the present study was a total of 117 Iraqi subjects, who admitted to the maxillofacial department at Al-Sadr Teaching Hospital in Al-Najaf city. The examination was performed on CT scanner; the eminence inclination was measured in two methods using sagittal section. Results: Clinically, the inclination of articular eminence was higher in edentulous subjects than i
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