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.
The research talks about the concept of investment allocations, showing its linguistic and idiomatic meaning, as well as the objectives for which the investment allocations are based, as well as the benefits of these allocations since it shows types of investment contracts, including: current and fixed assets and commitment allocations.
The research has been concluded with several results, including the protection of the banks and the investor. The contracting parties focus on specific dates that both parties are obliged to abide by, the research also shows the jurisprudence provisions for investment allocations, each ruling according to the specific branch.
... Show MoreThe Study addressed the effectiveness of dialogic communication in online public relations with an audience of higher education institutions in the United Arab Emirates. The study aimed to know about the interest extent of higher education institutions through their websites with the elements of dialogic communication in online public relations to communicate with their audience. The researcher used survey methodology and content Analysis tool as an essential tool for collecting information. Some of the important results of the study are: The websites of higher education institutions in terms of indicators of ease of use; the main links on the websites are clearly available on the opening page, there is a map on the websites, reduce depe
... Show MoreThe current research aims to identify the most important green productivity tools GPT and the possibility of applied in industrial companies in general and the companies operating in the province of Nineveh, in particular, as well as the study of some personality characteristics and functional, which is believed to be an impact on the application of these tools in industrial companies. Accordingly, the research community of managers in the company of medicines and medical supplies ready-made clothes _ operating in the province of Nineveh, who are (80) while the manager was subjected to research procedures (49) Director representing (61.25%)
... Show MoreSeeds of three American species of cucumber:-Lot number (EM285) signed as number 1,
To CAEEN F1 signed as number 2 ,and Hybird Super Green F1 signed as number 3, were
exposed to two kinds of physical effects .They were given :- 4 frequencies of the electric
current (0,1,2and 2.5) Am for five minutes using electro- magnetic generator .Then the three
species exposed to Ultra-Violet (UV)wave for four periods (0,30,60 and 90)sec. respectively
at 254 nm using Hood light .After exposure time the seeds were planted in sterlized
media(MS) with Benzyladenine (BA)and left in the incubator for2-3 weeks .Then ,plantlets of
the three species were taken to study the root system ,shoot system ,dry and wet weight for
them
Measurements of radon gas concentrations were carried out for 12 soil samples at 3 sampling depths (surface, 5 cm and 10 cm) collected from (4) locations in south Baghdad suburbs (Bu'aitha) using solid state nuclear track detector CR-39 and sealed can technique. Radon concentrations for surface samples were ranged from 402.2 to 1538.4 Bq.m-3 with an average 994.4 Bq.m-3. Whereas, radon concentration was ranged from 813.1to 2050.4 Bq.m-3 and from 1309.8 to 4626. 1Bq.m-3 with an average values of 1359.8 Bq.m-3 and 2338.3 Bq.m-3 for 5 cm and 10 cm depths respectively. Maximum radon level was found at the location near to the river (site S4) while the minimum radon level was f
... Show MoreBackground: Oral lichen planus (OLP) is a chronic immunologic disease. The etiology of OLP is unknown, viral antigens (for example EBV) have been proposed as etiologic agents. OLP may get transformation to malignancy so research on the presence of these in OLP lesions seems to be necessary. The aim of this study was to evaluate EBV expression immunohistochemically in OLP. Materials and Methods: Tissue specimens of 30 formalin fixed, paraffin-embedded tissue Blocks histologically diagnosed oral lichen planus was performed to evaluate EBV expression. Results: Expression of EBV was detected in epithelium of (46.6%) in the study samples in (OLP). no statistically significant correlation was found with clinical parameters except for a significan
... Show MoreAbstract: The issue of rebuilding the strategiccapacity of Iraq after the occupation and the US invasion in 2003 has been oneof the most contentious issues of debate and debate. It raises a number ofpolitical, social, economic, military and security problems. We say politicalprimarily because the climate and political conditions play a large and activerole along with other factors complementary to them. The important questionthat arises here is: How can the ruling political blocs move to the stage ofreconstruction without reservations? In order to answer this question, wedivided the study into three main axes. The first deals with the concept ofpower and its types. The second axis deals with the relationship betweenstrategic capa
... Show MoreTelevision contributes children the acquisition of knowledge, moral and social values through programs that are offered to them and the extent of the focus on the effective aspects of life in the age of the target stage. The subject of this research aims to know the children programs in Libya television through a comprehensive analytical study of the program entitled “zihur al-hayat” within the broadcast season from April 1, 2004 to June 30, 2004. It also focuses on trying to identify the Libyan television policy in broadcast educational content through the children's programs in the prevailing political and social conditions during the period of study as well as knowing the opinions of the children's sample under study in Al-Baidhaa
... Show MoreIraqi-Saudi Relations have witnessed a state of rapprochement over decades. However, this rapprochement was temporary and could not overcome the differences that formed the core of Iraqi-Saudi relations after 2003, relations between Iraq and Saudi Arabia deteriorated with the Iraqi governments that followed the rule of Iraq after 2003, especially the government of Nuri Al-Maliki in which relations reached the end of mutual accusations between the two parties. In order to promote the relationship between the two countries, a culture of moderation has to be propagated especially in the field of religion and the religious institution should be encouraged to open up to other sects and to recognize all sects as prelude to combating the cultur
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