It is found that hypersensitive teeth have a larger number and wider patent tubules than those of non-sensitive teeth. Objective: The aim of this study is to compare between the effects of diode laser at different power densities, with and without sodium fluoride on the sealing of exposed dentinal tubules and dentin permeability. Materials and methods: 118 teeth were used. Samples were divided into three major groups. The first consisted of 100 teeth used for permeability test. The second consisted of 16 teeth for measuring external surface temperature elevation while irradiation. The third, in turn, consisted of one pair of teeth observed under SEM for dentine surface morphology analysis. Results: For dentin permeability measurement, the results revealed a highly significant difference between the control group and 2, 3 W with varnish groups. For the external surface temperature elevation, the results revealed that temperature rise, for both laser alone and with varnish groups, was between (67-97.9 ∘C) at 1.6, 2 W. SEM analysis revealed that approximately optimum sealing of tubules occurred in 2W with the varnish group. Conclusions: The combined application of 940 nm diode laser at 2W with 809.7 W/cm² power densities, with sodium fluoride white varnish show a significant improvement in their effects on dentin permeability reduction as compared to each treatment alone.
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يتمثل الهدف الأساسي من الرقابة علىٰ تركز الشركات في منع آثارها المحتملة غير التنافسية الضارة بالهيكل التنافسي للسوق المعنية، وذلك لحماية حرية المنافسة فيها. وفي إطار ذلك لا بد من التحقق من أن تلك العمليات ليس من شأنها إعاقة المنافسة الفعّالة أو الحد منها بشكل كبير علىٰ نحو يترتب عليه التأثير علىٰ السوق المعنية بجعلها أقل قدرة علىٰ المنافسة مما كانت عليه، أي ضرورة التنبوء بكافة الآثار المحتملة التي ستترتب عل
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The Internet, networks and the means of communication in the world of communication and information have greatly influenced all aspects of the information cycle until things have been turned upside down, and it has even been said that today the world can be separated into two worlds: the world of pre-internet and post-Internet.
Perhaps one of the most important data of the Internet in the world of information and journalism is electronic publishing, which comes blogging as one of its forms. Blogs, which have begun slowly in the form of personal diaries, developed and spread on the Internet very quickly and started to have its own universe, the world of blogging. It has begun to make its way in the world of journali
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Urbanization can not be seen as a modern phenomenon. It has led people to live and live in cities for thousands of years. It should be noted here that the oldest villages and large cities have emerged after the crystallization of civilization, that the emergence of cities was one of the phenomena of civilization. There is no doubt that the cities after the emergence has contributed to the development of civilization effective contribution. There has been a civilizational progress when the man practiced agriculture and used metal tools and invented the wheels and went to write in the New Stone Age. In this period, many changes in the field have taken place in economic, cultural and social life. In the economic and cultural aspect, this tr
... Show MoreThis study aims to identify the role of forensic accounting in resolving banking disputes in the Iraqi environment, and to achieve this goal, the fiel
d survey method was used, as it is the most appropriate for studying the phenomenon in question and achieving its objectives. A sample of (50) male and female employees was selected, distributed among five banks listed on the Iraq Stock Exchange in the Baghdad governorate. The questionnaire tool prepared for this purpose was applied to them, which consisted of two main axes. The first axis included paragraphs of questions related to the importance of forensic accounting. The second axis relates to disputes At the end of the research, we reached a set of conclusions, the most import
... Show MoreIn this study the thermal conductivity of the epoxy composites were characterized as function of volume fraction, particle size of fillers and the time of immersion(30,60,90)days in water .Composites plates were prepared by incorporating (bi-directional) (0º-90º) glass fiber and silicon carbide (SiC) particles of (0.1,0.5,1)mm as particle size at (10%,20%,30%,40%) percent volume in epoxy matrix.
The composites shows slightly increase of the thermal conductivity with increasing volume fraction, particle size and increase with increasing the days of immersion in water. The maximum thermal conductivity (0.51W/m.K) was obtained before the immersion in water at 90 days for epoxy reinforcement by bi-directional glass fiber and SiC particl
Purpose: The aim of this study is to examine knowing the real role and impact of manufacturing flexibility on competitiveness through operations management practices, which is to determine the role and impact of manufacturing flexibility on competitiveness directly in the General Company for the Battery Industry. On the other hand, identifying the indirect role of flexible manufacturing systems in enhancing competitiveness. Theoretical framework: The main purpose of the theoretical framework is to identify all the dimensions and variables included in the current study, and thus form a deep scientific view of the study and its variables. Design/methodology/approach: field coexistence, personal interviews, and classification of
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