Background: Debonding orthodontic brackets and removal of residual bonding material from the enamel surface include critical steps that may cause enamel damage. The aim of the present study was to evaluate and compare the site of bond failure and enamel surface damage after debonding of three types of esthetic brackets (composite, ceramic, sapphire) bonded with light cure composite and resin-modified glass ionomer adhesive. Materials and methods: Seventy two maxillary premolars teeth were divided into three groups each group consisted of 24 teeth according to the type of brackets. Each group was subdivided into two subgroups (12 teeth for each) according to the bonding material that was used. After 7 days of bonding procedure, the brackets were debonded using specifically designed debonding device in which the brackets were debonded by a debonding pliers to simulate the actual clinical debonding procedure. Instron Universal testing was used to apply the debonding force on the debonding pliers which transferred to the bracket. The teeth and the brackets were examined with a 10X magnifying lens to evaluate the site of failure. After the removal of residual adhesive, stereomicroscope was used to evaluate enamel surface damage. Results: The most common type of bond failure was cohesive failure (Score II) in all esthetic brackets. While enamel cracks (scale I) were found to be the most type of enamel damage. Chi- square showed non-significant differences among different types of esthetic bracket bonded with same type of adhesive and between the same types of brackets (ceramic, sapphire) bonded with the two types of adhesive. On the other hand, there was significant difference between composite brackets subgroups bonded with the two adhesives. Conclusion: The bond failure mostly within the adhesive itself and higher enamel damage was resulted from mechanical debonding of these esthetic brackets.
Background: Powerlifters and bodybuilders use anabolic androgenic steroids (AAS) especially – as many as 55 percent of elite powerlifters admitted using these agents. In contrast to numerous documented toxic and hormonal effects of AAS their impact on the structure and function of the left ventricular (LV) was not yet fully understood.
The fact of having Journalism being open to people from different orientations professions, working as journalists requiring protection just to spread corruption, is one of the biggest threats faced by journalism.
Journalists noticed the spread of unprincipled journalists with no journalistic ethics amongst them, they tried to protect their profession from these corrupt outsiders who might annihilate the mighty of journalism. The principles of the journalism profession known as journalistic ethics, are one the most important formulations of the law concluded by the journalists and those concerned by the the profession, they were then published in public in order to prove their professionalism, especially for those who don’t und
... Show MoreIn this research (100* 40* 4 cm) solar cell panel was used in Baghdad at autumn season (2010), to get best solar cell panel angles experimentally, and then a mirror (40*50 cm) is use to concentrate incident sunlight intensity on a panel. At first case we get (Tilt angle ?P =60°and Surface Azimuth angle ?P =36°E) is the best angles and other case, we add a mirror at angle = 120° at bottom of panel, then we get output power (27.48watt) is bigger than without using a mirror (25.16watt). We can benefit from these cases in variety applications.
The research aims to identify and diagnose the public relations strategies in its digital online communications by the United Nations High Commissioner for Refugees (UNHCR) in managing the crisis of Iraqi refugees in Turkey. A content analysis form was designed for the digital content of the UNHCR's website dedicated to topics and issues concerning Iraqi refugees that were covered by the site, adopting a comprehensive enumeration approach. The study covered the period from 01/03/2022, to 30/06/2022. The research yielded several key findings, including the predominant use of media, advertising, and education strategies in managing the crisis of Iraqi refugees in Turkey. News and reports ranked first among the media
... Show More(1) Background: Plant flavonoids are efficient in preventing and treating various diseases. This study aimed to evaluate the ability of hesperidin, a flavonoid found in citrus fruits, in inhibiting lipopolysaccharide (LPS) induced inflammation, which induced lethal toxicity in vivo, and to evaluate its importance as an antitumor agent in breast cancer. The in vivo experiments revealed the protective effects of hesperidin against the negative LPS effects on the liver and spleen of male mice. (2) Methods: In the liver, the antioxidant activity was measured by estimating the concentration of glutathione (GSH) and catalase (CAT), whereas in spleen, the concentration of cytokines including IL-33 and TNF-α was measured. The in vitro expe
... Show MoreIn this numerical study a detailed evaluation of the heat transfer characteristics and flow structure in a laminar and turbulent flow through a rectangular channel containing built-in of different type vortex generator has been a accomplished in a range of Reynolds number between 500 and 100,000.A modified version of ESCEAT code has been used to solve Navier-Stokes and energy equations. The purpose of this paper is to present numerical comparisons in terms of temperature, Nusselt number and flow patterns on several configurations of longitudinal vortex generator including new five cases. The structures of heat and flow were studied, using iso-contours of velocity components, vortices, temperature and Nusselt n
... Show MoreThe city of Samawah is one of the most important cities which emerged in the poverty area within the poverty map produced by the Ministry of Planning, despite being an important provincial centre. Although it has great development potentials, it was neglected for more than 50 years,. This dereliction has caused a series of negative accumulations at the urban levels (environmental, social and economic). Therefore, the basic idea of this research is to detect part of these challenges that are preventing growth and development of the city. The methodology of the research is to extrapolate the reality with the analysis of the results, data and environmental impact assessment of the projec
Background: Sonographic examination is an important tool in assessment of normal and abnormal cervical lymph nodes. The aim of the study is to assess the distribution and the characteristic features of normal cervical lymph nodes in a sample of Syrian population. Materials and Methods: Fifty healthy Syrian subjects (25 men and 25 women) with an age of 20 -60years old, who had their cervical lymph nodes examined by ultrasound. Three hundred and two lymph nodes were detected. Lymph nodes were evaluated for their number, size, site, echogenic hilus, shape, as well as for the border sharpness. The subjects were categorized by age into four groups, (20 -30, 31 - 40 , 41 - 50 , 51- 60 years ). Statistical analysis of data was done using SP
... Show MoreObjectives: To determine the (QoL) for patients with permanent pacemaker and to find-out the relationship between
these patients’ (QoL) and their sociodemographic characteristics such as age, gender, level of education, and
occupation.
Methodology: ٨ purposive non-probability” sample of (62) patient with permanent pacemaker was involved in this
study. The developed questionnaire consists of (4) parts which include !.demographic data form, 2.disease-related
information form, 3.socioeconomic data form, and 4.Permanent pacemaker patient’s quality of life questionnaire data
form. The validity and reliability of the questionnaire were determined through the application of a pilot study. ٨
descriptive statistical a
Objective: to assess the risk factors of coronary artery disease patients.
Methodology: A non-probability (purposive) sample of (100) patients. The study population consisted of
a sample of adults from both genders whose ages were 30 years and more, and was newly diagnosed as
having CAD by coronary angiography in the cardiac catheterization unit of An Nasiriyah heart center.
Results: The result of the study showed that the most common modifiable risk factors were low HDL-C
levels (58%), smoking (53%), hypertension (46%), diabetes mellitus (34%), obesity (30%), high
triglycerides (19%), hypercholesterolemia (17%), and high LDLC (14%). All these factors were positively
and significantly associated with the development