Background: The use of electronic apex locators for working length determination eliminates many of the problems associated with the radiographic measurements (interference of anatomical structures, errors in projection such as elongation or shortening, and lack of three-dimensional representation). Its most important advantage over radiography is that it measures the length of the root canal to the apical constriction, not to the radiographic apex. The aim of this study was to assess the accuracy of a new fifth generation apex locator (Joypex 5) in recording the apical constriction and comparing it with a third generation apex locator (Root ZX) in vitro. Materials and method: Twenty four single-rooted sound human premolars, extracted for the purpose of orthodontic treatment and with fully-formed roots, were used in this study. Endodontic access cavity was prepared in each tooth and canal patency up to the apical foramen was checked with a #15 stainless steel K-file. No root canal preparation was performed. Root canal length measurement was done directly and electronically using two apex locators (Joypex 5 and Root ZX). Direct measurement of the root canal length was done by introducing a #15 K-file inside the root canal until its tip was just visible at the apical foramen, then removed from the root canal and its length was measured (in mm) and subtracted by 0.5 mm. For electronic measurement, the teeth were fixed in a sponge soaked in saline and the root canals were also filled with saline. The lip electrode was attached to the sponge and the apex locators were used according to the manufacturers' instructions. The file holder was clipped to the metal shaft of a #15 K-file and the file was then inserted inside the root canal and advanced until the display reading on the LCD of the apex locator was "0.5". The file was then removed from the root canal and its length was measured (in mm). The differences between the readings of each apex locator and the actual length of each canal were computed, and the results were analyzed statistically by paired t-test using SPSS Version 13. Results: The results of this study showed that the Joypex 5 apex locator showed a lower mean difference than the Root ZX apex locator as compared with the actual length, which was statistically significant (p<0.05). Concerning the accuracy of the two apex locators, Joypex 5 apex locator recorded the apical constriction exactly in 67%, while the Root ZX apex locator in only 25%. Within ±0.5 mm from the actual length, the accuracy of the Joypex 5 and the Root ZX were 83% and 67%, respectively. Within ±1 mm from the actual length, the accuracy of the Joypex 5 and the Root ZX were 100% and 96%, respectively. Conclusion: The Joypex 5 apex locator which is a fifth generation apex locator was more accurate in recording the apical constriction as compared with the Root ZX apex locator which is a third generation apex locator.
This research sheds light on those discrepancies in the use of ornaments, adornment and perfumes, as well as the art of cosmetics, in two important civilizations, namely, the Mesopotamian civilization as the earlier civilization, and the civilization of Yemen, which represents the first Arab civilization. Through the foregoing, our research includes two topics, the first topic included the history of the use of decorations, ornaments and perfumes in the civilization of Mesopotamia, while the second topic included the study of ornaments, adornment and cosmetic art in the ancient civilization of Yemen. And then the research came out with a number of conclusions that the researcher considers very important to highlight the differences and f
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To study the qualitative changes in testis tissue after carbon tetrachloride (CCl4) administration and to determine whether citric acid (CA) has a protective effect against testis damage induced by CCl4. This study compared two types of CA by measuring the histoarchitecture of the testis and serum levels of progesterone, estrogen and testosterone on mice. One of the most produced organic acid is citric acid. In this study, CA produced by microbial fermentation using Aspergillus Niger 5mg/kg and derived from citrus limon 400mg/kg (lemon). Mice were treated with daily intraperitoneal (i.p.) injection for seven successive days after randomly separated into six groups: (1) control, (2) CCl4 (0.02%), (3) limon citric acid (400 mg/kg), (4) CCl4 (
... Show MoreThe importance of the study stems from the fact that it deals with a very important subject, namely, the pivotal role played by E-banking in achieving the competitive advantage of the banking institutions operating in Algeria. By adopting the banking institution and adopting the elements of the electronic marketing mix and developing it as required by the environment The banking system of developments will inevitably be able to achieve excellence from its competitors as each of these elements have an important role in achieving competitive advantage, we relied in this study on studies and research that directly affect the problem of the study and we have put Estep In order to activate the contribution of e-banking in achieving competitiv
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In spite of the disappearing of a clear uniform textbook for teaching ESP at different departments and different colleges in both scientific and humanistic studies, the practitioners at those departments and colleges have to teach translation as one of the important requirements to pass the English language exam. The lack of defined translation activities is a noticeable problem therefore; the problem of teaching translation is diagnosed in that the students lack the ability to comprehend the text in English language and other translation knowledge and skills.
The study aims to suggest a translation strategy and then find out the effect of the translation strategy on ESP learners’ achievement in translation. A sample of 50 stud
... Show MorePurpose: The main objective of this paper is, to determine the optimal no. of technicians’ men in a workshop crew of an Industrial System. Theoretical framework: The purpose of applying these tools is to explore their ability to reduce costs and improvements that can be obtained in the process of providing services to the end customer. Design/methodology/approach: The literature structure review was built from analyzing 12 of scientific papers and books, from web sciences and the Elsevier database. The papers were analyzed from descriptive, methodologic, and citation characteristics. Finding: By applying the equation model of the paper, the optimal no. of technician men in the crew of the workshop can be determined when
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Agricultural companies could push investment forward and help in production base variation and developing production techniques. They also play a significant role in organizing and providing requirements of market economy. This work aimed at studying economic efficiency of the six agricultural companies that are registered at Iraqi stock market for the period 2005-2016. Capital of these companies was between (300 million-7.5 billion IQD). Several financial analysis indicators were applied such as activity percentages. Average of capital circulation was 0.91 for private company of agricultural production، and lowest share was for Iraqi company for producing and marketing field crops. Assets average circulation was highest for the pr
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الخلاصة
تشير نظريات علم اجتماع المعرفة الى ان ظهور مفهوم معين او سقوطه لايتم بمحض الصدفة، بل نتيجة تفاعل مجموعة من العوامل الثقافية والسياسية وحتى الاقتصادية ومن هنا فأن ظهور مفهوم الاثنية كان محصلة عوامل كثيرة خصوصاً بعد ان اصبح موضوع الاثنية في العقود الاخيرة من القرن الماضي وبداية القرن الواحد والعشرين محور نقاش رئيس في ميدان البحث الاجتماعي والسياسي، ليس في
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