This study evaluated the structural changes of enamel treated by the Regenerate system and carbon dioxide (CO2) laser against acid challenge. Thirty human enamel slabs were prepared and assigned into three groups: Group I: untreated (control); Group II: treated with the Regenerate system; and Group III exposed to CO2 laser. All specimens were subjected to an acid challenge (pH 4.5–7.0) for 14 days. Specimens were evaluated and compared at 120 points using five Raman microspectroscopic peaks; the phosphate vibrations ν1, ν2, ν3, and ν4 at 960, 433, 1029, and 579 cm−1, respectively, and the carbonate at 1070 cm−1, followed by Vickers microhardness test. The ratio of carbonate to phosphate was correlated to the equivalent microhardness numbers. The intensities of phosphate peaks ν1, ν2, and ν4 were reduced in all groups post-acid challenge, while the carbonate and ν3 were significantly increased (p < 0.000). Surfaces treated by Regenerate exhibited higher peak intensity of phosphate and carbonate before and after pH-cycling (p < 0.05). The mineral content in enamel had a direct effect on tissue microhardness, and the CO2-lased surfaces showed a reduced carbonate content and higher microhardness values. Both approaches induced surface changes that can protect enamel against acid challenge resulting in a significant benefit for dental healthcare.
Some children are suffering from introversion in kindergartens , so it must be confront and obviated by specialists because it will inevitably lead to unsatisfactory results reflect negatively on the individual and the community together . And the introvert child is a miserable child incapable of social interaction or give - and - take with colleagues , lack of integration of the child to life leads to the obstruction of participation with his peers in various activities. Introversion causes a real emotional deficit to the children of kindergartens which limits of possibility of their intellectual development and mental growth and that because of their isolation and poor focus in education
... Show MoreThe variety of clean energy sources has risen, involving many resources, although their fundamental principles remain consistent in terms of energy generation and pollution reduction. The using of hydropower system for energy production also has a dynamic impact in which it utilizes to harness the water for the purpose of energy production. As it is important to overcome the problem of accidents in the highway and rural areas in the case of server rainfall and flood by implementation a smart system that used for energy production. This paper aims to develop a controlled hydropower system installed in the drainage sinks allocated in highway roads used for producing. The proposed system consists of storage unit represented by pipes used for t
... Show MoreThe present research aims to design an electronic system based on cloud computing to develop electronic tasks for students of the University of Mosul. Achieving this goal required designing an electronic system that includes all theoretical information, applied procedures, instructions, orders for computer programs, and identifying its effectiveness in developing Electronic tasks for students of the University of Mosul. Accordingly, the researchers formulated three hypotheses related to the cognitive and performance aspects of the electronic tasks. To verify the research hypotheses, a sample of (91) students is intentionally chosen from the research community, represented by the students of the college of education for humanities and col
... Show MoreThis work describes an experimental setup to evaluate the photodynamictoxicity of 650 nm diode laser and 532 nm Frequency-doubled Q-Switched Nd:YAG laser on the growth of Candida albicans as well as the potential fungicidal effect when combining the laser irradiation with specific photosensitizers namely methylene blue, toluidine blue, acridine orange and safranin O. In this study the findings showed that the number of colony-forming units per millilitre (CFU/ml) of C. albicans decreased with increasing exposure time. In particular in the case of the frequency doubled Nd:YAG laser combined with safranin O, the best lethal effect occurred at 11 minutes exposure time with 2.26 J/cm² energy density (89.18% reduction) in comparison with the
... Show MoreExperimental investigations had been done in this study to demonstrate the effect of natural particles used as a reinforcement material to unsaturated polyester resin. The tensile test and water absorption were investigated according to (ASTM D638) and (ASTM D570), respectively. The influence of sunflower husk and pomegranate husk particles, used as a reinforcement material, on the tensile strength, Young's modulus and water absorption with different weight fraction (3%, 7% and 10%) and particle grain size (50µm, 100 µm and 150 µm), has been investigated. The water absorption of polymer composites was studied by measuring the specimen weight before and after immersion in water for one hundred days. In the experiments of tensile test,
... Show MoreBackground: The emergence of vaping as a popular alternative to traditional smoking has raised concerns regarding its potential impact on oral health. specifically affects the oral health of dental students, who are not only consumers of these products but also future practitioners tasked with educating patients on oral hygiene and health risks. purpose: This study investigated the dental and oral health impact of VAPE among male dental students. Methods: A self-administered questionnaire comprising 20 questions was meticulously designed to gather relevant data about their VAPE use and its implications on dental and oral health. Results: 43% of participants reported using VAPE, predominantly employing salt nicotine (48.8%) over free
... Show MoreBackground: Cigarette smoking (CS) is a periodontal disease risk factor, affecting clinical parameters such as bleeding on probing (BOP), plaque index (PI), gingival index (GI) and proinflammatory cytokines level. This study examines the impact electronic cigarette use on proinflammatory cytokines and periodontal parameters. Methods: In this non-randomized study, ninety participants diagnosed with gingivitis were assigned into three groups. examined the effect of oral hygiene instructions on periodontal parameters and inflammatory biomarkers. Thirty CS (n=30) vaping electronic-cigarettes (e-cig) (n=29), and non-smoker (NS) (n=31) was included. Clinical parameters including PI, BOP, and GI were recorded at baseline and after 3 weeks
... Show MoreTo study the response of the celery plant to nitrogen fertilization and spray with salicylic acid in the leaves content of nutrients, the research was conducted in one of the fields of the Department of Horticulture and Gardening Engineering / College of Agriculture / University of Baghdad within the 2019-2018 season. The research was carried out as a global experiment and with the design of complete randomized sectors (RCBD) and with three replicates, the first factor included the addition of nitrogen with three levels and its symbol (N) (N1 control), (N2) g / m2 18 ), (N3) 37 g / m2 and the second factor spraying acid salicylic is denoted by
This work consists of a numerical simulation to predict the velocity and temperature distributions, and an experimental work to visualize the air flow in a room model. The numerical work is based on non-isothermal, incompressible, three dimensional, k turbulence model, and solved using a computational fluid dynamic (CFD) approach, involving finite volume technique to solve continuity, momentum and energy equations, that governs the room’s turbulent flow domain. The experimental study was performed using (1/5) scaled room model of the actual dimensions of the room to simulate room air flow and visualize the flow pattern using smoke generated from burnt herbs and collected in a smoke generator to delivered through
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