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.
In this study; a three-dimensional model was created to simulate groundwater in Al-Haydariyah area of the governorate of Al-Najaf. A solid model was created to utilize the cross sections of 25 boreholes in the research region, and it was made out of two layers: sand and clay. The steady-state calibration was employed in six observation wells to calibrate the model and establish the hydraulic conductivity, which was 17.49 m/d for sand and 1.042 m/d for clay, with a recharge rate of 0.00007 m/day. The wells in the research region were reallocated with a distance of 1500 m between each well, resulting in 140 wells evenly distributed throughout the study area and with a discharge of 5 l/s, and the scenarios were run for 1000
... Show Moreon the subject of the provisions of recitation among students of the Islamic Sciences Colleges).
The researchers adopted the experimental method and chose an experimental design for the two equivalent groups by post-test. The research sample consisted of (60) male and female students from (second stage) - Department of Qur’an Sciences and Islamic Education - University of Diyala, and the two researchers were rewarded between the two groups of research in the following variables: (Chronological age calculated in months, degrees of recitation rulings subject in the previous year, the two researchers studied the same research groups, and lasted for an entire semester, the researchers prepared the observation card to measure the ru
... Show MoreBackground: Recently with improvement of dental implantology science, osseointegrated implants show a considerable durability, however; failures are not completely avoidable. Matrix metalloproteinase-2 (MMP-2) expression is disturbed in many pathological conditions such as peri-implantitis and periodontitis. This study was carried out to investigate the tissue expression of MMP-2 in the extracellular matrix of osseointegrated and diseased implants. Subjects and methods: Gingival biopsies were collected from six patients having osseointegrated or working implants and twenty with diseased or non osseointegrated implants and (6) controls having no implants. In situ hybridization technique was used to analyze the changes in immunoreactivity of
... Show MoreAims: The aim of this study was to evaluate the value and accuracy of longitudinal strain in detection of coronary artery disease compared to coronary angiography. Results: The left ventricular longitudinal strain-speckle tracking showed evidence of stenosis of left anterior descending artery, circumflex artery and right coronary artery in (86.1%), (76.4%), and (84.7%) respectively. For the stenosis in left anterior descending artery, the current study showed that the longitudinal strain was a good predictor for presence of significant stenosis with a sensitivity of (93.8%), specificity (75%) and accuracy (91.7%) compared with coronary angiography. For the stenosis in right coronary artery, the left ventricular longitudinal strain had
... Show MoreThe researchers aim of this research to analyze the reality of educational services in the city of Ramadi in order to reveal the efficiency of the spatial distribution of schools at the level of residential neighborhoods and the requirements of the population, based on the standards and indicators for this service.
The research problem related to the educational function of the city of Ramadi was formulated by asking about the efficiency of the spatial distribution of educational services and whether there is a balance in the distribution of schools to residential neighborhoods in a way that meets the requirements of the population, and in order to answer the research problem, the research hypothesis was formulated that there is
... Show MoreThe Developing economies of countries have witnessed essential changes to words the development of tourism industry in the 21st century . in addition to adopting same of policies and strategies to grow up with the tourism sector to make it one of the important economic sector to compete the tourist cal developments in the wear .
As for the tourism sector in Iraq ,it's still afresh one , has many of elements which can be in vested ,needs a wide strategies of tourist cal in statutes and variety completive services and change of success for the locale and forgin investor ,the essential aim after this research is to prompt the national economic through the tourism industry and making concisen
... Show MoreMersing is one of the places that have the potential for wind power development in Malaysia. Researchers often suggest it as an ideal place for generating electricity from wind power. However, before a location is chosen, several factors need to be considered. By analyzing the location ahead of time, resource waste can be avoided and maximum profitability to various parties can be realized. For this study, the focus is to identify the distribution of the wind speed of Mersing and to determine the optimal average of wind speed. This study is critical because the wind speed data for any region has its distribution. It changes daily and by season. Moreover, no determination has been made regarding selecting the average wind speed used for w
... Show MoreStress with all its kinds are the results of a nick development Leading to delinquency burdening the ability of people.. development gas its effect on self and body reflecting on health ( physically, Psychological. And mentally) and finally leading to death (Al emara,2001,2).
Stress refers to he degree of response of the individual to events and environmental changes in his daily life with their physiological effects such as headaches , backaches, and gastric ulcer that have different effect depending on the personality of the person and his psychological characteristics differences airing individuals ( Al emirs, zool,2 )
The aims:
- knowi
Background: Educational environment is one of the most important determinants of an effective curriculum. Students' perceptions of their educational environment have a significant impact on their behavior and academic progress. Objective: 1. To identify students’ perception to the educational environment.2. To identify any gender or class level differences in the students’ perception.Type of the study: This is a descriptive cross-sectional studyMethodology: The study was carried out on convenient sample of 150 students of 2nd and 5th grade. This study was done in Al Kindy Medical College, Baghdad, Iraq and conducted during the period from the 1st of October 2013 till the end of March 2014, by using DREEM questionnaire a validated uni
... Show MoreAccording to the European Union Water Framework Directive requirements, diatom metrics were used to assess the ecological status of surface waters in the Gaziantep central catchment (Turkey). A total of 42 diatom taxa were identified. A few environmental factors (especially lead, copper, orthophosphate, and chromium) played significant roles on the distribution of diatom assemblages among the sampling stations. The first two axes of the canonical correspondence analysis elucidated 91.6 % of the species–environment correlations with 13.9 % of the cumulative variance of species. The applied diatom indices (TIT – Trophic Index Turkey, TI – Trophic Index, and EPI-D – Eutrophication and/or Pollution Index-Diatom) showed different results
... Show More