Background:The demand for esthetic orthodontic appliances is increasing so that the esthetic orthodontic archwires were introduced. This in vitro study was designed to evaluate the surface roughness offiber-reinforced polymer composite (FRPC) archwires compared to coated nickel-titanium (NiTi) archwires immersed in artificial saliva. Materials and Methods:Three types of esthetic orthodontic archwires were used: FRPC (Dentaurum), Teflon coated NiTi (Dentaurum) and epoxy coated NiTi (Orthotechnology). They were round (0.018 inch) in cross section and cut into pieces of 15 mm in length.Forty pieces from each type were divided into four groups; one group was left at a dry condition and the other three groups were immersed in artificial saliva (pH=6.75 ± 0.015) at 37ºC for 1, 14 and 28 days intervals. The AFM was used to evaluatesurface analysis of all samples.ANOVA, Kruskal-Wallis, LSD and Mann-Whitney U tests were used to identify and localize the source of differences among the groups. Results:At each immersion period, FRPC wires exhibited the highest Ra among the study groups, except at 28 days immersion period where the Teflon coatings were the roughest. On the other hand, the least rough surfaces were the epoxy coatings when compared to analogous esthetic archwires, except at 1 day immersion period where the Teflon coatings had the least roughness. However, statistically non-significant differences were found between Teflon and epoxy at the dry condition and the 1 day immersion. Conclusions:The epoxy coated archwires are the best and the most appropriate esthetic orthodontic alignment archwires in term of the least surface roughness initially and over the course of study period.
One of the most important problems facing the world today is the energy problem. The solution was in finding renewable energy sources such as solar energy. The solar energy applications in Iraq is facing many problems . One of the most important problems is the accumulation of dust on the solar panels surface which causes decreasing its performance sharply. In the present work, a new technique was presented by using two-axis solar tracking system to reduce the accumulated dust on the solar panel surface and compared it with the fixed solar panels which installed at tilt angles 30° and 45°. The results indicated that the maximum losses of the output power due to accumulation of dust on the fixed solar panels is about 31.4% and 23.1% res
... Show MoreThis study was conducted with the aim to extract and purify a polyphenolic compound “ Resveratrol†from the skin of black grapes Vitis vinifera cultivated in Iraq. The purified resveratrol is obtained after ethanolic extraction with 80% v/v solution for fresh grape skin, followed by acid hydrolysis with 10% HCl solution then the aglycon moiety was taken with organic solvent
( chloroform). Using silica gel G60 packed glass column chromatography with mobile phase benzene: methanol: acetic acid 20:4:1 a
... Show MoreActing on the Holy Qur’an by contemplating its meanings, stopping at its commands and prohibitions, and everything in it that guides us to truth and mercy. The Holy Qur’an includes it for various purposes in one verse, and there is no doubt that this is part of the perfection of this great book, and one of the sciences of the fundamentalists is the indication of the context, and it is a great science of high rank, and it is one of the most important things that lead to the correct understanding of the miraculous and decisive book of God Almighty, and one of the best meanings of the Qur’an It was not from the context of the verses, and from here it can be said that the indication of the context is one of the origins of deriving lega
... Show MoreBackground: Systemic sclerosis (SSc) is a chronic autoimmune illness, which is consider by three main features: Sclerotic changes in the skin and internal organs, Vasculopathy of small blood vessels, Particular autoantibodies (1). The most important autoantibodies appeared significantly in SSc patients are anti-topoisomerase I autoantibody (Scl-70), anti-centromere autoantibody (ACA), and anti-RNA polymerase III autoantibody (RNAP3) (2). Anti-centromere antibodies (ACA) are infrequent in rheumatic conditions and in healthy persons but occur commonly in limited systemic sclerosis (CREST syndrome), and rarely appeared in the diffuse form of systemic sclerosis (3). Anti-Ro/SSA and antiLa/SSB, antibodies directed against Ro/La ribonucleoprot
... Show MoreThe studies on the antiviral compound chalcone in vitro in both tissue and organ culture systems against rubella virus glass that this compound relatively non toxic to the cell culture and organ culture of the concentration of 8 ug/ml or less, chalcone have significantly antiviral activity against rubella virus in tissue culture and organ culture. We find that a concentration of 0.03ug/ml or more inhibit the IOOTCID50 of rubella virus. The therapeutic index (TI) used in this study to evaluate the drug, the (TI) which is the ratio of the dose of drug which is just toxic (Maximum tolerated dose) to the dose which is just effective (Minimum effective dose). If this index is one or less it not possible to use the drug under the conditions outli
... Show MoreBackground: Implant stability is a mandatory factor for dental implant (DI) osseointegration and long-term success. The aim of this study was to evaluate the effect of implant length, diameter, and recipient jaw on the pre- and post-functional loading stability. Materials and methods: This study included 17 healthy patients with an age range of 24-61 years. Twenty-two DI were inserted into healed extraction sockets to replace missing tooth/ teeth in premolar and molar regions in upper and lower jaws. Implant stability was measured for each implant and was recorded as implant stability quotient (ISQ) immediately (ISQ0), and at 8 (ISQ8) and 12 (ISQ12) weeks postoperatively, as well as post-functional loading (ISQPFL). The pattern of implant
... Show MoreAbstract:
The phenomenon of financial failure is one of the phenomena that requires special attention and in-depth study due to its significant impact on various parties, whether they are internal or external and those who benefit from financial performance reports. With the increase in cases of bankruptcy and default facing companies and banks, interest has increased in understanding the reasons that led to this financial failure. This growing interest should be a reason to develop models and analytical methods that help in the early detection of this increasing phenomenon in recent year . The research examines the use of
... Show MoreIn this paper investigate the influences of dissolved CO2/H2S gases, crude oil velocity and temperature on the rate of corrosion of crude oil transmission pipelines of Maysan oil fields southern Iraq. The Potentiostatic corrosion test technique was conducted into two types of carbon steel pipeline (materials API 5L X60 and API 5L X80). The computer software ECE electronic corrosion engineer was used to predict the influences of CO2 partial pressure, the composition of crude oil, flow velocity of crude oil and percentage of material elements of carbon steel on the rate of corrosion. As a result, the carbon steel API 5L X80 indicates good and appropriate resistance to corrosion compared to carbon steel API
... Show MoreInternational satellite channels in Arabic are targeted to the region with their news bulletins and their innovative programs, attracting the interest of the Arab viewers in their news articles and programs with new ideas and methods as well as high technology in the production and synthesis of videos. Therefore, they work on framing the above, And the media policy that governs, so focused the problem of the study to try to answer the question of the President is how to frame the international satellite channels in Arabic to the phenomenon of terrorism? What are the aspects that are working to highlight and aspects that try to hide? The study adopted the survey methodology for the main news bulletins in the Russian channel today for the
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