Background: Thermocycling simulates the temperature dynamics in the oral environment. This in vitro study done to measure and compare the effect of thermocycling on the shear bond strength of stainless steel and sapphire brackets bonded to human enamel teeth using light cured orthodontic adhesive and debonded at various time, and to measure adhesive remnant index after debonding. Materials and Methods: one-hundred-twenty extracted upper first premolars for orthodontic reason were used in this study; depending on weather thermocycled or not, the sample was divided into two main groups, then within each group 30 teeth were used for stainless-steel brackets (Bionic®) and for sapphire brackets (Pure®). Both groups were subdivided into three groups (n = 10) according to the debond times: I: debond after 24 hour, II: debond after 7 days and III: debond after 30 days. Within 24 hr, half of the sample was thermocycled manually for 500 complete cycles between 5/55°C and the remaining sample was stored in distilled water at room temperature and water was changed daily until debond time for each group was performed. The adhesive remnant index was tested under 20X magnification lens using stereomicroscope. Results and Conclusions: Both bracket types demonstrated high shear bond strength values before thermocycling (P?0.05), whereas after 500 thermocycles, there were significant changes in shear bond strength resulted in marked reduction in the stainless steel brackets than in the sapphire brackets (P?0.05). Shear bond strength values increased with time for both stainless steel and sapphire brackets with and without thermocycling (P?0.05). The tendency of bond failure was increased at the bracket/adhesive interface rather than enamel/bracket interface in the stainless steel brackets whereas at the enamel/bracket interface rather than bracket/adhesive interface in the sapphire brackets.
A Al-Nuaimy, B Fadheel…, IPMJ, 2009 - Cited by 1
AN Adil A, F Basman M, 2009
The aim of the research is try to answer the questions about the importance of the participation of scientists in the scientific researcher Google Scholar for the professor and the university, and the extent of participation of Iraqi universities, and the rank of the University of Qadisiyah, and the number of participants and teachers of this engine, The research came out with several conclusions, the most important of which is that (21%) of university professors are involved in the google engine and most of the participants did not carry their full research through the site
The area around the Suez Canal has been chosen particularly Sinai to implement the new Suez Canal project parallel to the original 72-km-long channel due to the importance of the commercial site of the Arab Republic of Egypt, competing with shipping lanes, to accommodate the increasing maritime traffic passing through the Suez canal, and to provide special services for trade world and reduce the economic cost of marine trip. The establishment of six tunnels for automobile and railway transport to Sinai The cost of the establishment of this new channel and the establishment of the tunnels about (2.8) billion, of which 4 billion cost of the new channel. Project implementation period is one year. The new proj
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Economic organizations operate in a dynamic environment, which necessitates the use of quantitative techniques to make their decisions. Here, the role of forecasting production plans emerges. So, this study aims to the analysis of the results of applying forecasting methods to production plans for the past years, in the Diyala State Company for Electrical Industries.
The Diyala State Company for Electrical Industries was chosen as a field of research for its role in providing distinguished products as well as the development and growth of its products and quality, and because it produces many products, and the study period was limited to ten years, from 2010 to 2019. This study used the descriptive approa
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The research starts from studying the contractual budget, which is one of the modern trends in preparing public budgets, both operational and capital, in addition to meeting the requirements of the global trend to achieve sustainable growth in all fields, whether financial or non-financial, and tools for the contractual budget have been identified (participation contracts, planning Implementation, monitoring) and studying its impact in supporting sustainable development through its dimensions (economic, social, and environmental). The method of the questionnaire was adopted as a main tool in collecting information on research variables and distributing it to a sample of (70) individuals who dictate positions of professional respo
... Show MoreObjectives: To choose the best mode of delivery
for term, frank or complete, breech presentation
through studying the perinatal outcome of each mode of
delivery decided when managing a group of pregnant
ladies presented with breech delivery in our centre.
Methods: One hundred and fifty pregnant ladies
presented at term with singleton, frank or complete,
breech presentation for delivery in our centre during the
period from May 2004 toAugust 2005.
Mode of delivery, parity, gestational age, maternal age,
maternal medical illness, and birth weight where the
variables that have been tested in each delivery
included in the study to verify their relationship to
perinatal outcome.
Results: No significant
Abstract:
The aim of the research is to demonstrate the impact of the professional specialization of the audit companies in the detection of fraud in the financial statements of the economic units listed in the Iraqi market for securities for the period 2014-2015 through the application of the model (Carcello) to test the hypothesis of research on the impact of professional specialization of audit companies in the detection of fraud in lists The effect of the variables was revealed through the use of statistical models of logistic regression model and correlation coefficient. After testing the hypotheses of the research, a number of conclusions were reached. The most important was the existence of a signi
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Myrtle plant was washed, dried, and powdered after harvesting to produce a fine powder that was used in water treatment. created an alcoholic extract from the myrtle plant using ethanol, which was then analyzed using GC-Mass, Fourier Transform Infrared spectroscopy, and ultraviolet-visible spectroscopy to identify the active components. Zinc nanoparticles were created using alcoholic extract. We used FTIR, UV-Vis, SEM, EDX, and TEM to characterize zinc nanoparticles. Using a continuous processing procedure, zinc nanoparticles with myrtle extract and powder were employed to clean polluted water containing heavy metals.
Firstly used 2g with 20ml polluted water and the result was ( Fe 96.20%, Cr 84%, Pb 100%, Sb 93.70, Cd 100%, andCu
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