Background: The aim of this study was to evaluate and compare the apical microleakage around retrograde cavities prepared with ultrasonic technique and filled with (Biodentine™) Materials and methods: 40 extracted single rooted human permanent maxillary teeth with mature apices were selected. The roots were prepared chemo-mechanically using k-files with crown-down technique and then obturated with lateral condensation gutta-percha technique. Teeth were divided into four main groups according to the cavity preparation method either manual or ultrasonic technique: Group A (n=10): A class I retrograde cavity at root end was prepared with traditional handpeice equipped and placement of Biodentine with manual condensation. Group B (n=10): A class I retrograde cavity at root end was prepared with Piezoelectric ultrasonic device equipped with ultrasonic tip with only manual compaction of the material. Group C (n=10): traditional handpeice and placement of Biodentine using both manual compaction and 5 second ultrasonic activation. Group D (n=10): Piezoelectric ultrasonic device and placement of Biodentine with both manual compaction and 5 second ultrasonic compaction. The teeth were immersed in 1% aqueous Methylene blue dye for 72 hr. Then they were sectioned longitudinally with a diamond disc and the depth of dye penetration was examined under high magnification 20X. Results: Statistical analysis showed a highly significant difference in microleakage among the tested groups in which Piezoelectric technique has proved superiority in retrograde cavity preparation and compaction of Biodentin when dye penetration scores were compared. So microleakage was highest with cavities prepared with handpeice and manual application of retrograde material group A (2.73±0.39) followed by microprepared cavities group C (1.86±0.16), and it was lowest with ultrasonically-prepared cavities group B (1.09±0.28) and group D (0.26±0.19). Conclusion: ultrasonic preparation produced significantly less microleakage than conventional method. Also less microleakage was observed with ultrasonic compaction of Biodentin when compared with conventional method of compaction.
New biscarboxylato zwitterionic ligands, namely bis(N-carboxylatoethyl)-4,4 -dipyridinum) L1 and bis(Ncarboxylatopropyl)-)-4,4 -dipyridinum) L2, were synthesized from the reaction of 4,4 -dipyridine with 3-bromopropanoic acid and 4-bromobutanoic acid, respectively. The reaction of these ligands and the azido coligand with some metal ions resulted in the formation of polymeric complexes of general formulae [Cr2(Ln)(N3)4]Cl2·H2O and [M2(Ln)(N3)4] xH2O, where (M = Mn(II), Fe(II), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II); n = 1, 2; x = 1, 1, 1, 1, 0, 1, and 1, respectively.) The oxygens of the carboxylato group are coordinated to the metal ion in a bidentate fashion. The mode of bonding and overall geometry of the complexes were determin
... Show MoreSheet piles are necessary with hydraulic structures as seepage cut-off to reduce the seepage. In this research, the computational work methodology was followed by building a numerical model using Geo-Studio program to check the efficiency of using concrete sheet piles as a cut-off or reducer for seepage with time if the sheet piles facing the drawdown technique. Al-Kifil regulator was chosen as a case study, an accurate model was built with a help of observed reading of the measuring devices, which was satisfactory and helped in checking the sheet piles efficiency. Through the study, three scenarios were adopted (with and without) drawdown technique, it was found that at the short time there's no effect of the drawdown technique on
... Show MoreIn this study, pebble bed as an absorber and storage material was placed in a south facing, flat plate air-type solar collector at fixed tilt angle of (45°). The effect of this material and differ- ent parameters on collector efficiency has been investigated experimentally and
theoretically. Two operation modes were employed to study the performance of the solar air heater. An inte- grated mode of continuous operation of the system during the period of (11:00 am – 3:00 pm) and non-integrated mode in which the system stored the solar energy through the day then used the stored energy during the period of (3:00 pm – 8:00 pm). The results of parametric study in case of continuous operating showed that the maximum average temperatur
The study aimed to estimate the content of lead and determine the quality of the internal coating of metal cans through electrical conductivity as well as to determine the accuracy of the information card for some types of canned food that available in local markets. The information card test showed that all of these samples contained the name of the food, trade mark, country origin, weight, and components, as was indicated by the company producing in all of them except for the C12 sample which was otherwise, and the batch number was mentioned in all samples except for the C3 and C17 which was not clear and not mentioned in the C21, and the validity period was observed (produce and fini
... Show MoreObjective: To Evaluate the Roley of Cytotoxic T-Lymphocytek antigen 4 Polymorphism and soluble immune checkpoint level (PD-1,PDL-1 and CTLA-4 ) in SARS-Cov-2 patients. Methods: Fromt October 2020 to April 2021, the currentk study was conducted in Baghdad-Iraq. Ninety patients with Confirmatory SARS-Cov-2 by PCR were inclusion in the study, and they were seeking treatment at Medical City in Baghdad's Teaching Hospital (BTH). Patients with SARS-Cov-2 were divided into two groups: those with Sever SARS-Cov-2 symptom and those with mild - moderate SARS-Cov-2 symptoms (cross sectional study. Patients with another form of autoimmune illness, malignant, diabetes, under the age of 18 and pregnant women were excluded. Results: Data rega
... Show MoreThe competition in the hotel sector, globalization and the development of new information have forced the sector to continuously seek new techniques and arrangements to remain competitive through hotel industry companies, including Benchmarking and the application of this method in the hotel sector. The selection of the Rashid International Hotel by the Ministry of Tourism as a leading hotel or benchmark for comparison of other hotels in Iraq, and the selection of two hotels in Baghdad for comparison, namely (Ishtar International Hotel, Baghdad International Hotel) and the choice also by the Ministry of Tourism, N is to correct the course of practice to manage the cost and diagnosis of the weakness of the strengths and weaknesses in the
... Show Moresome ecological (physical and chemical varible) of water samples were studies monthly from December 2008 to May 2009 at two stations( St.1) Al - Chibayesh marsh and (St.2) Abu – Zirik marsh which are located in the south of Iraq . These variables included : Temperature, pH, EC, Dissolved oxygen , Total alkalinity, Nitrate, Sulphate, and phosphate, Si-SiO2 and Ca ,Mg, Cl, The marsh Considered as fresh water and alkaline. Abu-Zirik less than Al-Chibayesh.
Electronic banking services appeared as a result of laying the foundations for the application of electronic automation in the banking field, and despite the clear expansion in its adoption and implementation as an inevitable necessity imposed by international and national developments, its application was not ideal according to the level that was expected to occur after the abandonment of traditional banking services, which produced some risks Which is evident in the absence of a legal system, whether at the level of proving and authoritative electronic banking services such as electronic signature, Or at the level of protecting the confidentiality of these services and ensuring that they are not exp
... Show MoreThe promotion by its means lead a vital and important role at the level of all organizations, whether (industrial or service) in general, and financial markets in particular. The promotion is earns delved to be as one of the main operations which market uses it through various means of financial markets and companies which its shares listed in the aim of (finance or investment), with a view to the implementation and financing of public and private projects the one hand, or with a view to achieving profits through investment of speculative or... For other purposes, on the other hand.Accordingly, we find that the set of public and private goals joint between the financial markets and listed companies respectively, will serve the stra
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