Background: evaluate the effects of three different intracoronal bleaching agents on the shear bond strengths (SBS) and failure site of stainless steel and monocrystalline (sapphire) orthodontic brackets bonded to endodontically treated teeth using light cured orthodontic adhesive in vitro. Materials and methods: Eighty extracted sound human upper first premolars were selected, endondontically treated and randomly divided equally (according to the type of the brackets used) into two main groups (n = 40 per group). Each main group were subdivided (according to the bleaching agent used) into four subgroups 10 teeth each; as following : control (un bleached) group, hydrogen peroxide group (Hp) 35%, carbamide peroxide group (CP) 37% group and sodium perborate (SP) group . The bleaching process was applied three times (4 days intervals) sequentially and the bleached teeth were stored in artificial saliva four weeks before bonding. Orthodontic brackets were bonded with a light cure composite resin and cured with LED light. After passing 24 hours of bonding procedure, the brackets were debonded by a Tinius-Olsen universal testing machine, to measure the shear bond strength. After debonding, each bracket base and the corresponding tooth surface were examined using a stereomicroscope and their Adhesive Remnant Index (ARI) was recorded. Results: The ANOVA test showed that the SBS of stainless brackets was significantly reduced by intracorornal bleaching agents. Furthermore, LSD showed no significant difference in SBS between the three types of bleaching agents used in stainless steel group. Whilst for sapphire group, the results The ANOVA test showed no significant difference in SBS between the bleached groups and the control group. Chi-square comparison no significant difference in failure site between bleached and control groups in both brackets types used. Conclusion: The effect of intracoronal bleaching on SBS was reduced SBS of stainless steel and not for sapphire. However, the intracoronal bleaching had no effect on the failure site of orthodontic brackets used.
Objectives: The study aimed to clarify the role of Al-Sayyid Al-Ajall and his family in the service of the Mongol Empire. They worked to develop its administrative and military institutions, benefiting from their extensive experience in administration, politics, economics, and urban affairs. Due to their capabilities, they received the patronage of Genghis Khan and subsequent generations, earning the confidence of the ruling Mongol authority. As a result, they were granted significant powers within the state. Methods: The study relied on the analytical method to analyze historical texts, compare them with others, and discuss them accurately. Results: The study yielded several results, including the minister's keen interes
... Show MoreThe Boltzmann transport equation is solved by using two- terms approximation for pure gases and mixtures. This method of solution is used to calculate the electron energy distribution function and electric transport parameters were evaluated in the range of E/N varying from . 172152110./510.VcmENVcm
The electron energy distribution function of CF4 gas is nearly Maxwellian at (1,2)Td, and when E/N increase the distribution function is non Maxwellian. Also, the mixtures are have different energy values depending on transport energy between electron and molecule through the collisions. Behavior of electrons transport parameters is nearly from the experimental results in references. The drift velocity of electron in carbon tetraflouride i
Abstract
This research aims to design a multi-objective mathematical model to assess the project quality based on three criteria: time, cost and performance. This model has been applied in one of the major projects formations of the Saad Public Company which enables to completion the project on time at an additional cost that would be within the estimated budget with a satisfactory level of the performance which match with consumer requirements. The problem of research is to ensure that the project is completed with the required quality Is subject to constraints, such as time, cost and performance, so this requires prioritizing multiple goals. The project
... Show MoreIn this study, the melting-cooling method was used to prepare the chalcogenide compound S60-Se40-X-PbX. Four samples were obtained by partial replacement of Selenium with Lead in the weight ratios x = 0, 10, 20, and 30, respectively. The materials were mixed separately, ground, placed in quartz ampoules, and heated to 500 degrees Celsius. After conducting several operations on the samples, their insulating properties were studied, represented by the real dielectric constant and the imaginary dielectric constant, and the electrical conductivity was measured as a function of the frequency. It was found that partial replacement plays an impo
Background: Laparoscopic cholecystectomy has many difficulties which include port Insertion, Dissectionof the Calot’s Triangle , Grasping of the Gallbladder , Wall thickness, Adhesion and extraction of theGallbladder. Aim of the Study: To predict how difficult cholecystectomy will be from assessing the patientpreoperatively which, in turn, help in decreasing the risks on the patients and preventing post-operativecomplications. Patients and Methods: A prospective study conducted in the department of General Surgeryat Al-Ramadi Teaching Hospital for the period of nine months from 15th of May 2018 till the 15th of February2019. It included 60 patients, all of them were undergone laparoscopic cholecystectomy for Gallstone. Patientswit
... Show MoreThe formula of Ijarah and Ijarah ending with ownership is one of the investment formulas in Islamic banks, so this research has shed light on it in order to benefit from the experiences of the research sample banks, This research aims to find a reliable way for Iraqi Islamic banks, namely (leasing and leasing ending with ownership) in order to invest their money without usurious interests, The problem of the research emerges through the lack of awareness of the Iraqi Islamic banks to work with different Islamic financing formulas and their inability to invest their money through the adoption of their administrations for different formulas, including the leasing, and this is reflected in the decrease and fluctuation of its profits, Theref
... Show MoreIn this paper to isolate and study the properties of the cyclooxygenase-2 (EC: 1.14.99.1) enzyme in the blood of a patient suffering from rheumatoid arthritis and study the effect of natural products of the Soapwort on the activity of purified enzyme. The study involves taking 30 ml of blood from an adult woman 40 years old, who suffers from rheumatoid arthritis disease for 13 years. Serum is separated and subjected to a series of purification processes including: precipitation by ammonium sulfate, filtration by centrifugation radiator, dialysis in presence of ammonium bicarbonate, separation using the technology of ion exchange, lipholization and then estimating approximate molecular weight of the enzyme using gel filtration techni
... Show MoreThe main goal of this in vivo study was to evaluate the effect of 532nm Q-switched Nd: YAG Laser in combination with Human Serum Albumin 20% concentration (as a welding aid) on the liver tissue repair clinically, and histologically. The animals used in this study were 21 male rabbits divided into three main groups: control group (3 rabbits), conventionally treated group (9 rabbits) and Laser treated group (9 rabbits). Each two main groups (conventional and laser treated) consist of three sub-groups depending on the response evaluation at three different periods. The Laser group was treated using 532nm Q-switched Nd: YAG laser after adding human serum albumin immediately on the incised liver’s tissue. The energy of was 460mJ, and 4Hz fr
... Show MoreTotal quality management is considered a modern management concept that achieved success in all fields of various industrial and service sectors in advanced countries . One of these sectors is insurance. This concept aims at improving and developing the performance of insurance service continually . It is the gate that can enable radical change in the organization culture inside the company to transform it from using the traditional management style into using the modern style which achieves high quality standard of insurance service . As a result many insurance companies headed to applying the principles of total quality management in their companies . This study aims at raising the standard of the performance of the Iraqi Insurance Com
... Show MoreRheumatoid arthritis (RA), is an autoimmune, and inflammatory disease that is closely related to the destruction of cartilage and bone. DC-SIGN are important types of C-type lectin receptors (CLRs), expressed on dendritic cells and macrophages, and have a central role in regulating innate and adaptive immunity, function as pattern recognition receptors, and as cell adhesion molecules. Recent evidence has demonstrated that DC-SIGN is involved in the pathophysiological of chronic inflammation, so DC-SIGN has been linked to several autoimmune and may play an essential indicator in the pathogenesis and progression of RA. Therefore, the purpose of this study is to determine the serum level of DC-SIGN in RA patients, as well as the level of DC
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