Background: Optimal root canal retreatment was required safe and efficient removal of filling material from root canal. The aim of this in vitro study was to compare the efficacy of reciprocating and continuous motion of four retreatment systems in removal of root canal filling material. Materials and Methods: Forty distal roots of the mandibular first molars teeth were used in this study, these roots were embedded in cold clear acrylic,roots were instrumented using crown down technique and rotary ProTaper systemize Sx to size F2 ,instrumentation were done with copiousirrigation of 2.5% sodium hypochlorite and 17% buffered solution of EDTA was used as final irrigant followed by distilledwater, roots were obturated with AH26 sealer and Protaper gutta-percha point F2 and medium fine accessory gutta-percha using lateral condensation technique,roots were left for 7 days with 100% humidity at 37ºC in an incubator. Roots were randomly divided into four groups according to technique used for removing the root filling material (ten teeth for each group): group I: reciprocating technique and Wave One system, group II: continuous technique and ProTaper retreatment system, group III: continuous technique and R-Endo system, group IV: continuous technique and D–RaCere treatment system. All the roots were radiographed before and after removal of gutta-percha from both bucco-lingual and mesiodistal directions using custom made platform and digital radiograph system RVG to havea digitized images. The total surface area of all root canals was measured before removal ofthe gutta-percha and the area of the remaining gutta-percha filling in the canals after retreatment procedure from both directions. These measurements were analyzed with Adobe Photoshop CS6 software, the percentage of removed gutta-percha calculated. Results: Statistical analysis was performed and the result showed group Ihad the highest mean values in removal of root canal filling material in both bucco-lingual and mesiodistal direction of dental radiograph and there were significant difference between group I and most of the other groups ,there were non significant difference between group II,group III and group IV. Conclusion: This study was showed all the used retreatment systems did notcompletely remove the root canal filling material. The reciprocating technique was most effective method for removing gutta-percha and sealer than continuous rotary technique. Key words: Retreatment, reciprocating motion, root canal filling, rotary instrument.
In this study, the energy charging mechanism is mathematically modeled to determine the impact of design modifications on the thermofluidic behavior of a phase change material (PCM) filled in a triplex tube containment geometry. The surface area of the middle tube, where the PCM is placed, is supported by single or multi-internal frustum tubes in vertical triplex tubes to increase the performance of the heating and cooling of the system. In addition to the ordinary straight triplex tubes, three more scenarios are considered: (1) changing the middle tube to the frustum tube, (2) changing the inner tube to the frustum tube, and (3) changing both the internal and central tubes to the frustum tubes. The impact of adopting the tube desig
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Language is one of God’s blessings to human beings through which he
distingushed them from other creatures, then how if this language was arabic.
God honored this language and in which he descended his Gracious Boole
that gave it glory and magnificance, and made it an immortal revelation to the
arab nation in their poetry, oration, history and human tendency to the life of
knowledge, mind leadershipe, innovation and progress.
This study aimed at evaluating the arabic language come program for
the new teachers. The sample was of (25) participants who were shown a
questionaire consisting of (60) items distributed on (9) fields. Then, the data
was processed statisically by using preauency rate, Kai s
Modern sports clubs in Baghdad are in urgent need of adopting advanced technologies to enhance the efficiency of their operational and administrative processes. Among the most prominent of these technologies is cloud computing, which offers flexible and cost effective solutions for data storage and application management. However, sports clubs in Baghdad face significant challenges in adopting this technology, manifested in technical and administrative obstacles that limit the full utilization of cloud computing capabilities. The research problem lies in identifying and analyzing these obstacles, with the aim of providing a comprehensive understanding of the challenges faced by sports clubs in Baghdad. Sports clubs deal with a huge amount o
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The research aims at the relationship between Servant leadership dimensions test as an independent variable and an organizational trust as a variable dependent. Thus it was necessary to answer the following question: Is there a correlation relationship and impact between Servant leadership dimensions and organizational trust? To investigate the contents of the answer, the researcher selected a group of employees in Oil Products Distribution Company / Baghdad. The researcher adopted the analytical descriptive approach in completing his research which dealt with a random sample of (190) individuals representing the research society out of the total number of (376) person from the middle and high Leaders. Depending
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Today, the financial and banking sector is witnessing a qualitative shift thanks to financial technology services, which provide their services to many individuals and companies in quick, easy and less expensive ways compared to traditional means. Financial technology is a new form of financial science that combines financial transactions and technological skills concerned with providing financial services and improving the work environment within Banking institutions, and financial technology provides many advantages such as lower transaction costs, instant payment, and saving more time and effort in conducting banking
... Show MoreAs a kind of linguistic study, the study of presupposition in drama is one of captivating topic to explore, because of the capability of this topic to make people perceive the presupposition differently. Presupposition is one of the most important concepts in linguistics. It refers to the implicit inferences made in communication between people. These inferences are necessary to understand the utterances correctly. The research particularly endeavors to focus on the linguistic constructions that activate presupposition.
Every body has a size and mass that distinguishes it from others and makes it different from others. Some of these bodies are huge and large in size, and some are small and light in weight. Among these masses and bodies are some that are dealt with by their size and weight, each according to its quantity, weight, and cheapness. This is why they created quantities by which these weights and quantities could be estimated, so they used measures and weights for that. Objectives: The research aims to know some measures and weights, such as the wife’s maintenance, the amount of zakat, etc.I found it to be a widely spread topic, and widely used in the folds of jurisprudence. During my reading of jurisprudence books, I found jurists using many qu
... Show MoreNarcissism is a complicated phenomenon that can be reflected in the narcissist’s language. Investigating narcissism in terms of linguistics, and pragmatics in particular, does not seem to have been given its due attention, as this study reveals. Thus, this study is an endeavor to discover how narcissism is reflected in the American movie Big Eyes (2014). It is known for introducing narcissistic behaviors. This paper aims to identify the types, motivations, and pragmatic manifestations of narcissism in the selected movie. Three pragmatic theories are chosen to scrutinize narcissism in the data: Searle’s speech acts (1969), Grice’s maxims breaching (1975), and Culppeper’s impoliteness (1996). To cope with the nature of the
... Show MoreThe present study is a qualitative study that aims to investigate the way the Iraqi caricaturist,Dheaa Al-Hajjar uses caricatures to produce a satirical meaning humorously.Producing satire while at the same maintaining humor requires a creative thinking on the part of the caricaturist. Thus, the study examines the production of humorous satire in terms of creativity. The analysis is done from the cognitive linguistic point of view using Arthur Koestler's theory of bisociation as presented in his book The Act of Creation in 1964. The main principle on which the theory is based is that humor is created via linking (or bisociating in Koestler's terms) two habitually incompatible trains of thought in order to come up with a novel me
... Show MoreRacism changes its meaning, shape, purpose or function according to various factors such as time, place, motives, and backgrounds; among others. It seems, however, to have deep roots back in the history of mankind. Such a concept stems from a perceived difference with the other. It is fed by the feeling of being hierarchically superior in opposition to another party that is depicted as inferior. Since ancient times, racism is disguised in different forms and manifests itself on various levels. It is a truism that this ideology can be best presented via language.
Due to its negative implication, racism lends itself to a critical kind of research. As such, this paper is a critical pragmatic investigation for this phenomenon a
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