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.
In the period after the collapse of the Soviet Union in 1991, the Federal Republic of Russia witnessed a setback in the overall strategic performance of the country, as it went through a stage of performance flop between the orientation towards Europe in the era of President Boris Yelsen (1991-1999), or the change of direction towards Eurasia, as the Russian Federation managed After President Vladimir Putin assumed power in 2000, from rebuilding the same state and preserving national unity and social cohesion, as well as building a phased military doctrine that made clear moves in Russian strategic thought and future directions towards regions of eternal importance in Russian strategic perception Lack of a set of motivations based on it:
... Show Moreدور التدقيق الاستراتيجي لإدارة الموارد البشرية في بلورة القدرات التنظيمية دراسة استطلاعية في رئاسة جامعة بغداد
يهتم هذا البحث بدراسة الأجوبة المسكتة,وهي أجوبة سريعة وحاسمة تقطع حجة الخصم وتفحمه وتغلقالحوار.وقد أرتكز البحث على منهجية تداولية تنظرإلى فاعلية الجواب المسكت في المحاورة وإنهائها من زواياإنجازية و حجاجية.وقد تكون البحث من ديباجة ممهدةوثلاثة مباحث.وسلطتالديباجةالممهدةالضوء علىمفهومالجواب المسكتوشيوعهفي كتب الأدبوالأخبارونوادر الكلاموكيف يمكن النظر لهبوصفه وحدة حوارية تنبنيمنها المحادثة؟أما المبحث ا
... Show MoreThe current research is concerned with studying the decisive answers which are considered quick and conclusive. These answers can effectively interrupt the opponent's argument and close the dialogue.This research is concentrated on deliberative methodology focusing on the decisive answer's activity and ending them through several completing and argument sides. This research consists of an introduction and three parts, the current introduction is focused the light on the concept of decisive answers and its uses in literature and the scarce of speech, and how to consider it with one dialogue description,that dialogue constitute by ? The first part is concerned with those answers through the deliberative methodology and classifying decisive
... Show MoreThis research aims to demonstrate the knowledge pillars of the product life cycle assessment technique and how to measure the cost according to this technique, and to clarify its role in reducing costs, improving product quality and optimizing the use of available resources, and a set of results has been reached, the most important of which are: The separation of environmental costs through the use of product life cycle assessment technique helps the Management in handling the increase of these costs, reducing the rates of environmental pollution and preserving resources, which contributes to achieving the sustainability of the product, and based on the results obtained, a set of recommendations were presented, the most important of which w
... Show MoreBackground: An accurate adaptation of the crown to the finish line is essential to minimize cement dissolution and to preserve periodontium in fixed partial denture cases. An accurate adaptation of crown is possible only when preparation details are captured adequately in the impression and transferred to cast. For these reasons, gingival displacement is necessary to capture subgingival preparation details.The aim of the present study is to measure in vivo the horizontal displacement of the gingival sulcus obtained by using three new cordless retraction materials (Magic Foam Cord®, Racegel and Astringent Retraction Paste) in comparison to medicated retraction cord. Materials and method: Thirty-two patients requiring porcelain fused to me
... Show MoreThe importance of the research from a practical point of view lies in the fact that it presents a set of statistics and data that give a clear picture of how the Iraqi newspapers (the subject of the study) deal with the visit of "Pope Francis" to Iraq ، and what are the most prominent indicators and manifestations of that visit in promoting societal peace among the Iraqi public. From a scientific point of view، the research provides another scientific addition to the media library، especially with regard to journalistic treatments and methods of framing the Arab international press for the subject of the visit، which could be a starting point for other researchers to complete qualitative research in this field. The research prob
... Show MoreArab-Islamic architecture has undergone a change at multiple levels affected by modern technology, so the research sought to address the role of contemporary technologies on a fundamental and fundamental component of architecture, which is the architectural space, what is known as the essence of architecture and its ultimate destination, with a focus on the architectural space in the architecture of the contemporary Arab Islamic mosque, because the mosque’s architecture is so important in Islamic law and the belief of the Muslim person himself, where the mosque is the functional style produced by the Islamic faith and embodied in it, whereas, knowing the levels of influence of contemporary technologies in the architectural spac
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