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.
The aim of the present study is to provide the adequate knowledge about the role of time management in facilitate the work requirements for employees of the administrative department at the Ministry of Higher Education and Scientific Research. The research depend on studying four important dimensions which are (time planning, time organization, time direction and time observation). In addition to study other five dimensions which are (new procedures, clear procedures, short procedures, the available information and the simplicity of the methods
used).Questionnaire sheets consist of (38 questions) distributed to (170) employees and (146) sheets only were considered in the study. SPSS program was used
... Show MoreThe topic of the research aims to consolidate the concept of fair value, and then to identify the international financial reporting standard and its role in the application of fair value in the Iraqi local environment and the possibility of using it in determining the value of the company. To achieve the goal of the research, the analytical approach was adopted for the data and information that was obtained by the researcher by conducting interviews with a number of bank and department managers in a sample of Iraqi banks registered in the Iraq Stock Exchange, and then analyzed by adopting some quantitative financial methods. The researchers reached a set of conclusions, the most important of which was the impact of fair value accoun
... Show MoreObjective(s): In the present study, glycerin is used as a substitute for tin-foil and cold mold seal (Alginate mould seal)
in the process of curing heat and cold-cure acrylic resin denture base against stone and plaster.
Methodology: 60 specimens were prepared from heat-cure acrylic resin and cold-cure acrylic resin denture base. The
study includes 12 groups of specimens depending on the type of processing, investment material and type of
separating medium that are used in curing process. Each group of them contains 5 specimens for each test.
Some of physical properties of the processed acrylic denture base that (water sorption and solubility) have been
compared with those processed using tin-foil and tin-foil substitut
Abstract: To study the effect of nickel chloride on bone composition of mice, a number of biophysical and biochemical parameters have been made use. The animals were divided into control and experimental and further subdivided into three groups I, II and III according to the dose of nickel chloride (NiCl2) administered to them i.e. 5.8, 12.8 and 28.2 mg/kg body weight, respectively. Femur bones were obtained by sacrificing the animals three weeks after weaning them once a week. The percentage loss between the wet weight and dry weight of femur in control animals was found to be 32.5+1.5 .In the three experimental groups I,II and III, the percentage loss was 30.4+1.4, 35.3+2.3 and 38.9+2.2 respectively. The percentage loss between the wet we
... Show MoreThis study examined the effects of water scarcity on rural household economy in El Fashir Rural Council / North Darfur State- western Sudan. Both quantitative and qualitative methods were used as to get a deeper understanding of the impact of water scarcity on the rural house economy in the study area. 174 households out of 2017 were selected from 45 villages which were distributed in eight village councils forming the study area. Statistical methods were used to manipulate the data of the study. The obtained results revealed that water scarcity negatively affected the rural household economy in the study area in many features. These include the followings: much family efforts and time were directed to fetch for water consequentl
... Show MoreOne of these plants utilized in traditional medicine is Lactuca seriolla Linn., which belongs to the Asteraceae family. It goes by a variety of common names in the world, including prickly lettuce, wild lettuce, jagged lettuce, and Kahu and khas. The work aimed to isolate and characterize some bioactive constituent(s) from the aerial part of Lactuca serriola utilizing Combiflash NEXTGEN and high-performance liquid chromatography (HPLC). Lactuca serriola (aerial part) was extracted with 80% ethanol, then fractionated with hexane. Then 250 mg of hexane extract was mixed with 4 g of silica gel and loaded in cartilage, then bounded to the gold column of combi flash using a solvent system comprised of ethyl acetat
... Show MoreTwo experiments were carried out, the first at the College of Agriculture - University of Baghdad during spring season 2017 Everest cv. class (Elite) was used to study the effect of foliar application of calcium and magnesium and addition of humic acid to the soil on potato growth and yield, The layout of the experiment was factorial within RCBD design using three replicates. Calcium and Magnesium sprayed with concentrations (0, 500, 1000 mg.L-1), while the humic acid was added to the soil with (0, 0.75 gm.m2), The second experiment included storage of tubers produced from the spring season, with to study the effect of field treatments on improving the storability of the tubers. The results showed that the treatment of calci
... Show MoreBackground: Green Tea is made from the leaf of the plant “Camellia sinensisâ€. Green tea is reported to contain thousands of bioactive ingredients including catechins which have shown great promise for having antimicrobial effects. Periodontal diseases represent one of the most prevalent diseases around the world and the main etiologic factor behind it, is plaque accumulation, in addition certain kinds of bacteria have been detected frequently in subjects suffering from periodontitis, Several studies suggested that the outcome of periodontal treatment is better if particular pathogens including Aggregatibacteractinomycetemcomitans can no longer be detected after therapy. Materials and Methods: plaque samples were collected from 2
... Show More