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.
Cumhuriyet Üniversitesi Fen-Edebiyat Fakültesi Sosyal Bilimler Dergisi | Volume: 48 Issue: 2
In the period after the collapse of the Soviet Union in 1991, the Federal Republic of Russia witnessed a setback in the overall strategic performance of the country, as it went through a stage of performance flop between the orientation towards Europe in the era of President Boris Yelsen (1991-1999), or the change of direction towards Eurasia, as the Russian Federation managed After President Vladimir Putin assumed power in 2000, from rebuilding the same state and preserving national unity and social cohesion, as well as building a phased military doctrine that made clear moves in Russian strategic thought and future directions towards regions of eternal importance in Russian strategic perception Lack of a set of motivations based on it:
... Show Morehe current research aims at showing the correlation and effect of the internal environment analysis in the quality of health service in AL_Elwiya Maternity Teaching Hospital, researcher depended on the integral method in the "analytical descriptive method" for the study of the relation between the main variables and the sub-variables throughout data collection required by the theme of this study, a case study" in tackling the data and information related to the financial aspects of the internal environment.
The problem of the study was manifested in the essential question, that is (is there internal struc
... Show MoreThe first molecular research on Iraqi centipede fauna is presented in this article. Between October 2022 and May 2023, during various climatic circumstances, centipedes were collected from several locations in four provinces of Iraq. Three families, represented by four genera, underwent molecular identification, and five species were found. From the order Scolopendromorpha family Scolopendridae, two species were recorded, Scolopendra morsitans Linnaeus, 1758, and S. cingulata Latreille, 1829, Cormocephalus sp.; while from the order Lithobiomorpha, family Lithobiidae, one species was recorded for first time in Iraq; Lithobius crassipes L. Koch, 1862 from the order Geophilomorpha family Himantariidae, one species Bothriogaster Signata
... Show MoreThe rent is one of the sources of investment that generates returns for the owner of the housing unit, and it is also one of the importance expenditure for the tenant.
The importance of this research comes in addressing the deficiency in the field of analyzing the factors affecting the rental value of residential units, which affects many segments of the population of Baghdad.
The aim of this research is analyze and evaluate related variables on the rent value of residential units in neighbourhood 409 in city of BAGHDAD, which is a hypothesis that: There are a set of variables affecting the rental value, including those related to the internal environment of the dwelling, such as: income level, plot area, building area, n
... Show MoreEncouraging micro-enterprises for comprehensive economic development are crucial to achieve the ambitious vision 2030 of the Kingdom of Saudi Arabia.
Small and Medium enterprises are inputting around 15.5 per cent to GDP while 33 per cent contribution as a private sector to Saudi Arabia's gross domestic product (GDP). This study aims to identify the most important factors that affect the efficiency of small enterprises in Saudi Arabia. To accomplish this objective, the study was conducted for small projects via the comprehensive inventory method under the supervision of the Institute of Entrepreneurship. A total of 282 questionnaires were collected from entrepreneurs and the differentiation analysis
... Show MoreThe utilization of artificial intelligence techniques has garnered significant interest in recent research due to their pivotal role in enhancing the quality of educational offerings. This study investigated the impact of employing artificial intelligence techniques on improving the quality of educational services, as perceived by students enrolled in the College of Pharmacy at the University of Baghdad. The study sample comprised 379 male and female students. A descriptive-analytical approach was used, with a questionnaire as the primary tool for data collection. The findings indicated that the application of artificial intelligence methods was highly effective, and the educational services provided to students were of exceptional
... Show MoreThe current study is designed to achieve the goal of early detection of heart disease because it is the main risk of death. Some biomarkers were measured as well as the percentage of the effect of certain risk factors in people with myocardial infarction and heart failure. The study included 40 serum samples from people with heart disease. The effectiveness of the creatine kinase (CK-MB), as well as its temporal and albumin effects, as well as sodium ions in people with myocardial infarction and heart failure, were compared with the control group. as shown below:
-The first group consisted of 25 blood samples from people with myocardial infarction and 15 serum samples from people with heart failure. Blood
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