Background: The geriatric patients wearing removable partial dentures are increasing in proportion. At the same time, the root caries prevalence accompanied by gingival recession is increasing. A variety of vehicles can deliver fluoride into the oral cavity, including fluoride mouth-rinse, fluoride dentifrice, topical fluoride, and fluoride-releasing restorative materials, all of which effectively prevent root caries and suppress recurrent caries. This study aimed to evaluate the effect of sodium fluoride addition on some mechanical properties of heat cure acrylic denture base material. Material and method: A total of 90 samples were prepared in this study, then divided into three main groups according to the type of test used (hardness, tensile and transverse strength tests). Each main group was subdivided into three main subdivisions according to percentage of sodium fluoride addition to the heat cure acrylic denture base material (control no addition, 2%NaF ,and 5%NaF sodium fluoride groups) Results: The sodium fluoride addition to acrylic denture base materials showed slight but non significant increase in transverse strength and tensile strength tests while the results showed significant and highly significant differences for 2%NaF and for 5%NaF shore D hardness groups respectively. Conclusions: Addition of 2% and 5% sodium fluoride to heat cure acrylic resin is considered advantageous as the mechanical properties of resin denture base materials in respect to hardness tensile and transverse strength were not adversely affected.
The research aims to apply the activities of the green value chain as one of the modern administrative techniques that economic units resort to develop solutions to the pollution problems that occur due to the activity of economic units and their products that may cause damage to the environment as well as the waste of natural resources and to identify the production of environmentally friendly products and reduce the costs of environmental failure of both types Internal and external that may be borne by economic units such as taxes, fines and compensation due to nonobservance of environmental requirements and the preservation of human health and protection of the environment. To achieve the goal of the research, the researchers rel
... Show MoreThe research aims to identify the current (after the readings in the collection of foreign
students to the geographical material) To achieve this, the researcher developed the following
null hypothesis:
No statistically significant differences at the level of (0.05) between the average scores who
are studying the use of article readings and the average external degree students who are
studying material in the traditional manner of collection.
The researcher has chosen Qsidia middle school Amma, which includes six divisions for
Grade average, randomly selected Division (a) to represent the control group, while
representing the Division of (c) the experimental group and reached the research sample (44)
student, b
Imam al - Karji replies to some Islamic groups
In his book the jokes of the Koran
Salt stress negatively affects germination and seedling growth. Sorghum cultivars (Bohuth70, Inqath and Rabeh), seed soaking in dry yeast extract (3, 6 and 9 g l-1) in addition to dry seeds and electrical conductivity (4, 10 and 16 dS m-1) were studied. Traits of germination ratio at first and final counts, lengths of radicle and plumule, seedling dry weight and seedling vigour index were studied. The cultivar of Bohuth70 and concentration of yeast extract (9 g l-1) were superior at all studied traits, while all traits values were reduced with increased saline stress. The combination (Bohuth70×9×4) was superior to most other treatments at first and final counts, radicle length and seedling dry weight, while superiority of plumule length a
... Show MoreThis study was carried out to evaluate the hepato-protective property of (Arachis hypogea L.) peanut skin extracts in CCl4 induced hepatotoxicity in mice. The antioxidant activity was measured utilizing 2, 2-diphenyl-1-1 picrylhydrazyl (DPPH) radical scavenging capacity. The results showed that the methanolic extract was the highest free radical scavenging activity than the aqueous extract with values (92.34 ± 0.45 and 87.62 ± 0.44) respectively in 12 mg/mL compared to 89.61 ± 0.34 for Butylated hydroxytoluene (BHT) and 93.25 ± 0.06 for vitamin C, which means that the methanolic extract of peanut skin is superior to BHT. Furthermore, the total phenolic content was analyzed by using Folin-Ciocalteu method, the amount of total phenol in a
... Show MoreThe effect of molecules intersystem crossing (Kisc) on characteristics
(energy and duration) of a Passive Q- switched Laser Pulse has been
studied by mathematical description (rate equations model) for
temporal performance of which was used as a saturable absorber
material (passive switch) with laser. The study shows that the energy
and duration pulse are decreasing while the molecules intersystem
crossing into saturable absorber energy levels is increasing.
The objective of this study is to estimate the effect of the hydro-ethanolic catechin extract toward blood glucose, lipid profile and liver functions in alloxan diabetic mice. 50 healthy mice (25-30 g) were divided into five groups of ten animals for each. Group A received normal saline as normal control group. To induce diabetes, alloxan (150 mg/kg), intraperitoneal (i.p.) single dose was injected to groups B, C, D and E. Group B represents diabetic control group. Groups C, D and E received ethanolic catechin extract (30 mg/kg and 40 mg/kg) for different periods of 1, 2 and 3 weeks as treated groups. Blood glucose, serum lipids [Total Cholesterol (TC), Triglycerides (TGs) and High Density Lipoproteins (HDL)], asparagine transaminase (AST),
... Show MoreThe object of this work is to investigate the effect of the addition of methanol on the shelf life and color characteristics of novolak resin. Different percentages were added and two mechanisms were suggested for the addition. High ortho structure (1, 2-3) novolak resin was prepared and used in the above investigation. Experimental determination using FT-IR and UV-spectroscopy showed that on the addition of 30% of methanol and according to the second mechanism of addition novolak shelf life increased to 12 months without obvious decomposition and color change. It is suggested that methanol plays an important role in the inhabitation of the reactive sites on the resin that are responsible for the oxidation of the polymer when exposed to
... Show MorePMMA (Poly methyl methacrylate) is considered one of the most commonly used materials in denture base fabrication due to its ideal properties. Although, a major problem with this resin is the frequent fractures due to heavy chewing forces which lead to early crack and fracture in clinical use. The addition of nanoparticles as filler performed in this study to enhance its selected mechanical properties. The Nano-additive effect investigated in normal circumstances and under a different temperature during water exposure. First, tests applied on the prepared samples at room temperature and then after exposure to water bath at (20, 40, 60) C° respectively. SEM, PSD, EDX were utilized for samples evaluation in this study. Flexural
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