Background: Impression materials, impression trays, and poured stone cast have been said to be the main source of cross infection between patients and dentists. However, it was observed that disinfection of the impression is not performed systematically in routine dental practice. Disinfection of alginates either by immersion or spray technique was found to cause dimensional inaccuracies, although with proper disinfection of alginates there were small dimensional changes. A variety of fluoride releasing products designed for topical use is currently available. Following their use, varied amount of fluoride is systemically absorbed depending on the fluoride concentration and the manner of its use. The objective of this study was to evaluate the effect of addition (0%, 0.25%,0.5%,1%, 2%, 3%, 4% ) of (NaF) as a self-disinfection to alginate impression material powder and its effect on setting time, tear strength, dimensional change and accuracy of alginate impression materials. Materials and methods: A total No. of (700) specimen were used in this study.These specimens were divided into (5) main groups according to the tests used. Each of the four main groups contain (70) specimen divided into 7 subgroups (ten specimens to be tested for each (7)concentrations which is composed of six percentages of NaFwith alginate powder (0.25%,0.5%,1%, 2%, 3%, 4% )and one for control (0% NaF) , while the fifth group (Microbiological test) contain 420 specimen were divided between Streptococcus mutans and Candida albicans as (120) specimen for each one that was subdivided into three subgroups (specimens taken before impression casting, specimensafter pouring of alginate with stone andspecimens of stone were taken from the casts) in which it contain the same subgroups of the other concentrationsof (NaF) to test its efficacy against (Streptococcus mutans and Candida albicans). Results: Tear strength for all experimental impression materials was greater than those of the control products. There were no statistically significant differences between the dimensional change tests and also reproduction of detail test.With regard to setting time of the impressions, statisticallyreduction were seen between the control and experimental groups of alginate impression materials that contain (NaF). Self-disinfection of alginate impression material containing NaF showed a significant reduction in the count of cell forming unit of microorganisms immediately after impressions were made. Conclusion: In cooperation of specific concentrations of (NaF) as a disinfectant in alginate dental impression produced a significant reduction of contamination, also they caused non-significant effect on dimensional stability, detail reproduction and significant increase in tear strength. Therefore it is recommended as step in preventing cross contamination. Keywords: Alginate, NaF, Candida Albicans, streptococcus mutans.
The rapid increase in the number of older people with Alzheimer’s disease (AD) and other forms of dementia represents one of the major challenges to the health and social care systems because of a large number of people affected. Early detection of AD makes it possible for patients to access appropriate services and to benefit from new treatments and therapies, as and when they become available, and to plan for the future. The onset of AD starts many years before the clinical symptoms become clear. A biomarker that can measure the brain changes in this period would be useful for early diagnosis of AD. Potentially, the electroencephalogram (EEG) can play a valuable role in early detection of AD. Damage caused to the brain due to AD leads t
... Show MoreNanosponges (NS) of etodolac(ETO) was prepared using the emulsion solvent diffusion method ; the effects of drug: polymer ratio, the effect of level concentration of internal phase and stirring time and other variables that effect on the physical characteristics of NS were investigated and characterized, The selected formula was lyophilized then incorporated into hydrogel ; which also evaluated .The results show that the formulation that contain Drug: PVA:EC in ratio 1:3:2 is the best with smallest particle size 40.2±0.098 with polydispersibility0.005 and in vitro release 97.6±0.11%, , ETO NS Carbopol hydrogel produced a significant(p<0.05) improvement of the in vitro release than pure ETO hydrogel.
The outstanding evidence of phthalimide pharmacophore in securing enhanced biological activities had encouraged further research and development into phthalimide-based derivatives as potential new drugs. In this study, phthalimide core was hybridized with aldehydes giving integrated imines displaying different types of functionalities and at alternating positions. The resulting compounds, therefore, provide an innovative window to explore possible differential biological effects as antioxidants and anticancer agents. A total of sixteen compounds were synthesized, and each was verified by FT-IR, H NMR, C NMR, and MS characterization. Herein, a facile single-step synthesis method was employed substituting the conventional two-step che
... Show MoreThe curriculum is considered one of the most important corners for the educational process, it participates in achieving the educational equilibrium between its elements.
The curriculum of (History of the Art) in the college of Art Education / dept. of plastic art education and ceramic as the other curriculums and due to the subject of history of the art develop the knowledge, taste and experiment for art studier also this subject has a direct relation with practical educational activities like colors and growth the knowledge of the student in field of contents and symbols and evidences of meaning in old , medium and contemporary arts, due to the fact that this curriculum has been applied since long time more than four years, and
... Show MorePolymer additives binder system provides many properties useful in thermal energy storage (TES) then developed the efficient energy storage materials and green strength bodies system.
This paper studies the thermal energy storage property for polyvinyl alcohol (PVOH) / paraffin wax (WPw) blends. To enhance paraffin wax thermal conductivity, PVOH as a material which high conductivity was employed. A fixed weight of Paraffin wax was dispersed with PVOH heterogeneously at different additive weights ratios of PVOH/Pw (50/50, 67/33, 75/25, and 80/20) wt. ratio respectively. The composite material was prepared using wetted pressing method.
Both base materials (polyvinyl alcohol and paraffin wax) were scanned using differential
... Show MoreThe importance of the research lies in preparing exercises using a proposed device to learn the skill of thehuman wheel on a machine rug of ground movements of the artistic gymnastics. As for the research problem:Through the presence of the two researchers as teachers and observers of this sport in the gymnastics hall,they noticed that there is difficulty in the students’ performance of the skill of the round off on the machineof the mat of ground movements, according to the researchers’ opinion, the reason for this is that skillsare taught with the limited availability of assistive devices, as well as the lack of use of these devices inexercises according to biomechanical variables, although they facilitate the learning process
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The advertising mail is considered as one of potential tools that followed to transfer the printed messages to the consumers and public customers whom are located at homes or works. This type of advertising is preferable due to the zero expense to receive the announcements of products, which became recently one of the successful procedures to create new customers and keep them in touch with direct communication. It is also possible to send them to specific group of people who can be classified by the advertisers to select even by name their own clients to give the personality to the clients for a long term of communication.
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... Show MoreThe interest in pre-service teacher training has become influential in teaching English as a foreign language, and the purpose of this training course is to prepare qualified teachers to teach effectively through the application of this technique by undergraduate students. This research aims to find out the effect of using the seven principles of good practice as a teaching technique on the fourth stage student-teachers’ performance at the College of Education for Women/University of Baghdad, during the academic year 2017-2018. The sample includes (60) students selected according to the stratified sampling method. The observational checklist used by the department to assess the student teachers’ performance during the practicum perio
... Show MoreThe existing investigation explains the consequence of irradiation of violet laser on the optic properties of (CoO2) films. The film was equipped by the utilization of semi-computerized spray pyrolysis technique (SCSPT), it is the first time that this technique is used in the preparation and irradiation using a laser in this technique. From the XRD analysis, the crystalline existence with trigonal crystal system was when the received films were processed by continuous violet laser (405 nm) with power (1W) for different laser irradiation time using different number of times a laser scan (0, 6, 9, 12, 15 and 18 times) with total irradiation time(0,30,45,60,75,90 min