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-situ gelation is a process of gel formation at the site of application, in which a drug product formulation that exists as a liquid has been transformed into a gel upon contact with body fluids. As a drug delivery agent, the in-situ gel has an advantage of providing sustained release of the drug agent. In-situ gelling liquid suppositories using poloxamer 188 (26-30% W/W) as a suppository base with 10% W/W naproxen were prepared, the gelation temperature of these preparations were measured and they were all above the physiological temperature. Additives such as polyvinylpyrrolidin "PVP" ,hydroxylpropylmethylcellulose "HPMC", sodium alginate and sodium chloride were used in concentration ranging from (0.25-1
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The study of the validity and probability of failure in solids and structures is highly considered as one of the most incredibly-highlighted study fields in many science and engineering applications, the design analysts must therefore seek to investigate the points where the failing strains may be occurred, the probabilities of which these strains can cause the existing cracks to propagate through the fractured medium considered, and thereafter the solutions by which the analysts can adopt the approachable techniques to reduce/arrest these propagating cracks.In the present study a theoretical investigation upon simply-supported thin plates having surface cracks within their structure is to be accomplished, and the applied impact load to the
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Emulsion Liquid Membrane (ELM) is an emerging technology that removes contaminants from water and industrial wastewater. This study investigated the stability and extraction efficiency of ELM for the removal of Chlorpyrifos Pesticide (CP) from wastewater. The stability was studied in terms of emulsion breakage. The proposed ELM included n-hexane as a diluent, span-80 as a surfactant, and hydrochloric acid (HCl) as a stripping agent. Parameters such as mixing speed, aqueous feed solution pH, internal-to-organic membrane volume ratio, and external-to-emulsion volume ratio were investigated. A minimum emulsion breakage of 0.66% coupled with a maximum chlorpyrifos extraction and stripping efficiency were achieved at 96.1% and 95.7% at b
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Background: Adolescent pregnancy is associated with major health consequences for adolescent pregnant women including medications and oral health problems such as dental caries and periodontal disease. Pregnancy is a unique state of physical, hormonal, and metabolic changes that can result in an oral cavity imbalance. Changes in salivary components and a decrease in salivary flow rate caused by an increase in progesterone may compromise saliva's protective effects, resulting in dental caries.
Objectives: To evaluate dental caries experience in adolescent pregnancy.
Method: A sample including 80 pregnant ladies were recruited in this study and categorized into a study grou
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This study was carried out to determine the effect of extras of orange peel of (Citrus sinensis) in concentrations (1,5, 10) % as well as stomachic effect for the powder of the plant with doses of 5,10 , 15/gm on the biological activities of the adults of Tribolim confusum . The effect of powder from the adults has been evaluated using different concentrations of the orange peel. The results showed that the powder have significant effect on the mortality rates of adults. and caused reduction in number of adults after 3 days with 5,10,15/gm killed (30,40, 43.3)% respectively. The use of different doses of Citrus sinensis peels powder not impact significantly after just one day. The extract of essential oil also caused growth inhibition in
... Show MoreIn this paper, Nordhaus-Gaddum type relations on open support independence number of some derived graphs of path related graphs under addition and multiplication are studied.
Ninety nine swabs were collected from patients with diabetic foot ulcers (DFU), all swabs were cultured on different selective media for screening, 46 isolates confirmed as S. aureus by API staph. The results of antibiotic susceptibility test revealed that all isolates were resistant to metronidazole, 34 isolates were resistant to cefoxitin, ceftriaxone, and meropenim, 23 isolates were resistant to ciprofloxacin and norfloxacin, 17 and 16 isolates were resistant to tetracycline and trimethoprim, respectively; while all isolates were sensitive to tigecycline. The results of minimum inhibitory concentration (MIC) that carried out by using vancomycin, tigecycline and linezolid for 8 isolates, MIC results were1-2 µg /ml
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