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.
Meaning letters in Arabic are characterized by the diversity and abundance of their linguistic material, and are also distinguished by their large number and types, to the point that some of them have reached a hundred letters confined to five categories
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This study aimed to identify the changes in total protein in saliva and sera samples of patients with oral squamous cell carcinoma in comparison to those of healthy controls. These changes were followed using electrophoresis (PAGE). Meanwhile, determinations of albumin, globulin and albumin to globulin ratio were carried out on sera samples only.Two groups were the participants in the present study, 18 patients with Oral Squamous Cell Carcinoma (OSCC), and 20 ages and gender matched healthy controls.
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In this study, performance characteristics such as power take off (PTO) power consumption, fuel consumption, fuel consumption for the unit field-unit product were determined at different working speeds with two different PTO applications (540 and 540E) in a single row disc type silage machine. In particular, the 540E PTO application greatly reduces fuel consumption for unit work. The best results in terms of hourly fuel consumption were achieved in 540E PTO application and V1 working speed. When the field - product fuel consumption is evaluated, the best results were obtained with the 540E PTO application at the V3 working speed. When an evaluation is made considering all the parameters, it is concluded that the 540E PTO application will p
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In this paper, a mathematical model for the oxidative desulfurization of kerosene had been developed. The mathematical model and simulation process is a very important process due to it provides a better understanding of a real process. The mathematical model in this study was based on experimental results which were taken from literature to calculate the optimal kinetic parameters where simulation and optimization were conducted using gPROMS software. The optimal kinetic parameters were Activation energy 18.63958 kJ/mol, Pre-exponential factor 2201.34 (wt)-0.76636. min-1 and the reaction order 1.76636. These optimal kinetic parameters were used to find the optimal reaction conditions which
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The research includes a clinical study of Preptin with other parameters. The normal value of preptin in hypothyroidism (2638.4±280.0) in female while (2960.4±256.6) in male, in hyperthyroidism (589.0±90.1) in male, while in female (993.2±103.9), diabetes (2465.6±282.4) in female, in male (2085.5±282.8), in diabetes & hypothyroidism (3314.3±177.3) in male,(3179.4±265.7) in female, but control group in female (427.8±60.4), in male (384.7±62.4) at age (20-45) years they were divided into five groups: group one (G1) consisted of 30 hypothyroidism. The two group (G2) consisted of 30 patients with hyperthyroidism. And three group (G3) consisted of 30 healthy group, four group (G4) consisted of 30 patient with diabetes, and five group (G
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The current research aims at finding out how to properly and correctly manage waste and solid waste and reduce the difficulties faced by all countries. However, it is becoming increasingly acute in developed cities because their economies are growing rapidly. It is necessary to identify the modern methods used in developed countries in managing wastes. The use of modern waste management techniques is a coordinated effort by international agencies within the borders responsible for them. The problem of the study can be identified in the lack of clarity of environmental management procedures in place. The importance of the research contributes to providing greater capacity to the administrative and technical leadership in the municipality
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his study aimed to evaluate the effects of different doses of melatonin on liver function in adult rats. Eighteen Wistar adult albino rats (Rattus norvegicus), approximately 13–16 weeks old and weighing 230 ± 10 g, were randomly divided into three groups (n=6 per group) and treated orally for 30 days as follows: Group A1 received 10 mg/kg body weight (B.W) of melatonin; Group A2 received 20 mg/kg B.W of melatonin; and the control group (Group A) received distilled water. At the end of the treatment period, blood samples were collected via cardiac puncture, and serum was separated for biochemical analysis. Parameters assessed included oxidative stress markers (malondialdehyde (MDA), reduced glutathione (GSH)) and liver enzymes (aspa
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The current study was designed to investigate the presence of aflatoxin M1 in 25 samples of pasteurized canned milk which collected randomly from some Iraqi local markets using ELISA technique. Aflatoxin M1 was present in 21 samples, the concentration of aflatoxin M1 ranged from (0.25-50 ppb). UV radiation (365nm wave length) was used for detoxification of aflatoxin M1 (sample with highest concentration /50 ppb of aflatoxin M1 in two different volumes ((25 & 50 ml)) for two different time (15 & 30 min) and 30, 60, 90 cm distance between lamp and milk layer were used for this purpose). Results showed that distance between lamp and milk layer was the most effective parameter in reduction of aflatoxin M1, and whenever the distance increase the
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Background: Meclizine hydrochloride (MCZ) is an antihistamine that is used as an antiemetic to prevent and cure nausea and vomiting. Because of its limited water solubility and first-pass metabolism, it exhibits variable absorption. Objective: To formulate and evaluate MCZ as an intranasal in situ gel with increased residence time and permeability. Methods: We made an inclusion complex of MCZ using various cyclodextrins as a complexing agent to help the drug dissolve better. The complexes were studied, and the ones that were better at dissolving were chosen to be used in the creation of an in situ gel with poloxamer 407 (17–20% w/v) and hyaluronic acid (0.25–0.75% w/v). Prepared formulas were subjected to various evaluation tes
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