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.
The influences of the Cu substitution at Hg site in the HgOd layer, upon the
microstructure, Tc and oxygen content of Hg-1223 have been investigated. High
temperature superconductor with a nominal composition Hg1-xCuxBa2Ca2Cu3O8 + δ for
Cu ( 0 £ x £ 0.5) have been prepared by the two-steps solid state reaction method
under optimum conditions. XRD showed a tetragonal structure with a high ratio of
Hg-1223 superconductor phase. Tc enhancement has been determined with the Cu
concentration was is found to be Tc = 153 K for x = 0.3, while the oxygen content
observed variously with Cu concentration. Hg1-xCuxBa2Ca2Cu3O8+δ structure, oxygen
content and Tc behavior have been discussed.
The avoidance of failure in construction projects is not an easy task, which makes the failure of the construction project to achieve its objectives a major problem experienced by all countries in the world, especially Iraq. Where nearly two-thirds of the construction projects in the world have been suffered by significant problems as an increase in the cost of the project, delay in the specified duration for execution, and stopping the project. Therefore it is required to study and apply new methods for managing the construction project to ensure its success and achieve its objectives. The aim of this study is to study the Agile project management method and its impact on the construction project. In addition, to identi
... Show MoreThe theatrical show consists of theatrical techniques that form the space to display the play that may form conscious visual effects about the receiver. The current search included the (Research problem) which is the immediate question ((What makes the theatrical techniques dazzling and visually exciting in a certain theatrical show?))
It also included (the importance of research) by highlighting the importance of theatrical techniques and the mechanism of contrast.
It also identified the visual stimulus of theatrical techniques in the theater show.
It also included the (research limits), which were temporally determined by the period (1990-1998) and spatially, the Iraqi theater shows (Baghdad), in which theatrical techniques c
The CenomanianÐEarly Turonian reservoirs of the Mishrif Formation of the Mesopotamian Basin hold more than one-third of the proven Iraqi oil reserves. Difficulty in predicting the presence of these mostly rudistic reservoir units is mainly due to the complex paleogeography of the Mishrif depositional basin, which has not been helped by numerous previous studies using differing facies schemes over local areas. Here we present a regional microfacies-based study that incorporates earlier data into a comprehensive facies model. This shows that extensive accumulation of rudist banks usually occurred along an exterior shelf margin of the basin along an axis that runs from Hamrin to Badra a
The paper investigates the impact of role-playing as a classroom technique on Iraqi EFL students’ speaking skill on Iraqi EFL students at the college level. The students are 40 college language students in University of Baghdad, College of Education Ibn-Rushd randomly chosen. Then, they were divided into two groups, experimental and control groups. Thirty questions were applied to both groups as a pre-test of speaking and the students asked to answer them orally. The experimental group was taught speaking skill of the targeted role-play technique while the control group was taught in traditional method. After 20 lessons of the teaching, the post-test of speaking was conducted in which the students in both groups were asked to answ
... Show MoreChaotic features of nuclear energy spectrum in 68Ge nucleus are investigated by nuclear shell model. The energies are calculated through doing shell model calculations employing the OXBASH computer code with effective interaction of F5PVH. The 68Ge nucleus is supposed to have an inert core of 56Ni with 12 nucleons (4 protons and 8 neutrons) move in the f5p-model space ( and ). The nuclear level density of considered classes of states is seen to have a Gaussian form, which is in accord with the prediction of other theoretical studies. The statistical fluctuations of the energy spectrum (the level spacing P(s) and the Dyson-Mehta (or statistics) are well described by the Gaussian orthogonal ens
... Show MoreThat the essential contribution of this research is a description of how complex systems analysis service of the properties of the queue in Baghdad Teaching Hospital using a technique network is techniques method (Q - GERT) an acronym of the words:
Queuing theory _ Graphical Evaluation and Review Technique
Any method of assessment and review chart where you will be see the movement flow of patients within the system and after using this portal will be represented system in the form of planned network probabilistic analysis and knowledge of statistical distributions appropriate for times of arrival and departure were using the program ready (Win QSB) and simulatio
... Show MoreThis study aimed to evaluate serum levels of steroid hormones and human chorionic gonadotropin (hCG) hormone in preeclamptic Iraqi pregnancies compared to those of healthy pregnancies.This study enrolled 120 pregnant women, divided into four groups:1. 30 healthy pregnant women.2. 37 pregnant women with mild preeclampsia3. 53 pregnant women with severe preeclampsia4. 90 pregnant women with preeclampsia Preeclamptic women and their severe cases but not mild cases had significantly (P<0.01) increased levels of serum hCG as compared with healthy pregnancies. By contrast, sera levels of estradiol were significantly (P<0.01) decreased in total preeclamptic groups and their severe cases but not in mild group as compared to healthy pregnant wome
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