Background: Reduction in bond strength when bonding was done immediately after intracoronal bleaching procedure has been recognized. The purpose of this study is to assess the effect of antioxidants (10% sodium ascorbate (SA), 0.1M thiourea and7% sodium bicarbonate (SB)) on reversing bonding strength of composite resin to bleached dentin. Materials and method: Sixty upper 1st premolar teeth, were selected, the crowns of the teeth were embedded in acrylic resin blocks exposing a flat dentin from the buccal surface, then divided into 6 groups (10 samples each). Bleaching for the experimental groups was performed using 35% hydrogen peroxide bleaching gel (pola–office).Group A (Negative control group; dentin samples immediately bonded with composite without bleaching)Group B (Positive control group; dentin samples bleached and immediately bonded with composite). Group C (Dentin samples bleached and stored for 14 days in DDW then bonded with composite). Group D (Dentin samples bleached and treated with 10% (SA) then immediately bonded with composite). Group E (Dentin samples bleached and treated with 0.1M thiourea then immediately bonded with composite). Group F (Dentin samples bleached and treated with 7% SB then immediately bonded with composite).The shear bond strength was determine using instron testing machine. Results: Bleaching the dentin with 35 % hydrogen peroxide gel for 24 minutes resulted in reduction in bond strength of the bleached teeth when bonding was performed immediately after bleaching. Delayed bonding of composite to the bleached dentin for 14 days will result in a highly significant increase in the shear bond strength. Conclusion: Treating the bleached dentin with 10% (SA) in water base showed a highly significant increase in the shear bond strength of the composite to dentin and reversing the bond strength value to the level of the unbleached dentin. Treating the bleached dentin with 0.1M thiourea significantly increased the shear bond strength of the composite to dentin.
In this study, the researcher aimed to define and measure the relevance and effect of the governmental organizations in complying with Iraqi Ministry of Transportation's requirements towards achieving the social responsibility, embodied in the ten commandments of the United Nations Findings displayed the availability of realization regarding organization managers towards social responsibility with their various capabilities and tendencies in relation with the representing entries of those Ten Commandments.The study showed the relation between the effectiveness of those organizations and dimensions of the ten commandments of social responsibility, with the existence of a significant effect for the said effectiveness on achiev
... Show MoreThis research aims to identify the role of radio advertising in promoting purchasing decisions of Iraqi audiences, especially that the placement of the announcement through the Iraqi radio stations dealt with a little of Iraqi researchers, and the goal of the research to know the extent of public exposure to the radio advertising through Iraqi radio and patterns of exposure,disclosure of the reasons for public hearing of the radio advertisement, identifying the most important factors influencing the decision to buy in the radio advertisement, this research is descriptive in terms of type as the researcher used the survey method,questionnaire and scale for data and information collection, the sample was selected according to the purp
... Show MoreAccording to the topics of study, The intensity of the news coverage of the Abu Ghraib scandal and the US soldiers' torture of Iraqi prisoners have become apparent since the scandal was revealed on April 29, 2004 until May 30, 2004 and the period in which the coverage of this scandal had intensified not only in Al-Zaman, but in all newspapers, magazines and other media locally and internationally. And according to a research taken from Al-Zaman magazine that showed great interest in highlighting the event, interpreting it, following up its roots and results, and showing contradictory claims and slogans between the US and Britain, particularly in respecting human rights and the spread of justice, equality and well-being in Iraq specifical
... Show MoreAn application of neural network technique was introduced in modeling the point efficiency of sieve tray, based on a
data bank of around 33l data points collected from the open literature.Two models proposed,using back-propagation
algorithm, the first model network consists: volumetric liquid flow rate (QL), F foctor for gas (FS), liquid density (pL),
gas density (pg), liquid viscosity (pL), gas viscosity (pg), hole diameter (dH), weir height (hw), pressure (P) and surface
tension between liquid phase and gas phase (o). In the second network, there are six parameters as dimensionless
group: Flowfactor (F), Reynolds number for liquid (ReL), Reynolds number for gas through hole (Reg), ratio of weir
height to hole diqmeter
بهذا البحث نقارن معاييرالمعلومات التقليدية (AIC , SIC, HQ , FPE ) مع معيارمعلومات الانحراف المحور (MDIC) المستعملة لتحديد رتبة انموذج الانحدارالذاتي (AR) للعملية التي تولد البيانات,باستعمال المحاكاة وذلك بتوليد بيانات من عدة نماذج للأنحدارالذاتي,عندما خضوع حد الخطأ للتوزيع الطبيعي بقيم مختلفة لمعلماته
... Show MoreThis research on women under the title (Empowerment of women… From value education to the creation of human morality), includes a disclosure of the reasons that prevented women from performing their human role in the development of human societies and treatments that can provide to solve this big problem in the life These communities, especially the Eastern societies and the religious ones, believe that the woman has not received the care and care to raise her human values in order to contribute to the required social contribution, for historical, economic, moral, religious, social and cultural reasons. And by shedding light on specific definitions of the most important rules on which the research relied
... Show MoreIn the present study, the aim was made to identify the relationship between thyroid autoimmunity (TAI) and female infertility. The study was performed on 30 infertile women and 22 age-matched healthy fertile control age (33 ± 5 years). Overall, serum prolactin (PRL), thyroid stimulating hormone (TSH) assay is the key test for the diagnosis and management of hypo and hyperthyroidism. Anti-TPO Ab and anti-TG Ab were measured. The mean ± SE of serum PRL (31.080 ± 3.06) ng/ml was significantly (P<0.05) higher in infertile group compared with control (16.191±1.36) ng/ml. Serum TSH was significantly (P<0.05) higher in infertile group (5.689 ± 1.12) µIU/ml compared to control group (2.282 ± 0.18) µIU/ml. The prevalence of positive
... Show MoreThis study was conducted to test the hypothesis that the duration of time spent by the student inside the examination rooms answering the all kinds of written ex-amination questions has some kind of a positive effect on the final score he will get from that exam. And if there arc gender differences in this respect. Students and methods: Data on the final examinations of the autumn quarter was gathered on 892 examina-tions conducted at the end of this quarter , this included male participants of 566 and females of 326. Examinations were on twenty different subjects , including all of the first five years of the undergraduate students of Iraqi College of Medicine for the academic year 2002 — 2003 . The scheduled time of the examinations was
... Show MoreThe aim of this message to monitor this phenomenon throught the Quran , which is the constitution of the Islamic nation and Hariatha as well as to express kasalah integrity , justice honesty , patience , abd pacr .
We feel this vocabulary to hight athical values advocated by the Quran and the need to build commitment to the orthodox society free of corruption that leads ta a disorder of the human society .
The outcome of the study the researcher found that faith to a number of results was most notably the advent of righteusness in the Holy Quran meaning of comprehensive RPR spacious field and breadth Maadenh .