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.
The recent development in communication technologies between individuals allows for the establishment of more informal collaborative map data projects which are called volunteered geographic information (VGI). These projects, such as OpenStreetMap (OSM) project, seek to create free alternative maps which let users add or input new materials to the data of others. The information of different VGI data sources is often not compliant to any standard and each organization is producing a dataset at various level of richness. In this research the assessment of semantic data quality provided by web sources, e.g. OSM will depend on a comparison with the information from standard sources. This will include the validity of semanti
... Show MoreBioavailability is the objective for an optimum formulation. The target of the analysis is to maximize both the fluidity and disintegration profile of class II weakly compounds that are water-soluble. Anti-dyslipidemia drug rosuvastatin calcium (RC) (bioavailability 20%) through formulating as nanofibers (NFs) using electrospinning (ES) technology. Twenty formulas were prepared, and different polymers and polymer combinations with various concentrations were used such as polyethylene oxide (PEO) polyvinyl pyrrolidine (PVPK-30), and hydroxypropyl methylcellulose (HPMC). Three distinct groups of maximum parameters, including polymeric solution, electrospinning method, and ambient parameter, are capable of influencing the creation alon
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The protozoan parasite Entamoeba histolytica is a causative agent of amoebiasis, where it causes millions of cases of dysentery and liver abscess each year. Metronidazole is a drug of choice against amoebiasis. The drug is a choice because of its efficacy and low cost, but at the same time it causes several adverse side effects; therefore, it is important to find effective medications to treat amoebiasis without any complications or any side effects. The aim of this study is to evaluate the effectiveness of different concentrations (50, 75 and 100 µg/ml) of silver nanoparticle (AgNPs) against trophozoites stages of E. histolytica in vitro. The results showed a significant decrease (p ? 0.05) in numbers of trophozoites stages after treated
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Darifenacin hydrobromide (DH) is the more recent uroselective M3 receptor antagonist for treating uncomplicated overactive bladder (OAB). This study was aimed to formulate DH as fast dissolving buccal films (FDBFs) using a solvent casting method to enhance patient’s compliance.
Films were prepared by using polyvinyl alcohol (PVA) as a film forming polymer. Different types and concentrations of superdisintegrants (croscarmellose sodium, sodium starch glycolate, indion 414) were used to select the best formula by studying the physicochemical properties of the films, disintegration time (DT) and percent drug release.
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The Arabic pronouns received a lot of attention from the ancient Arab grammarians, so they explained their origins, the different forms of their structure, and the aspects of the Arabs’ use of them, and explained the aspects and reasons for these uses, with what they had of linguistic insight, which guided them to clarify the truth of these pronouns.
And recently, this research seeks new knowledge of the development of the structure of the nominative pronouns (he), (she), (them), (taa), and (waw) between dialects and towards classical Arabic, by analyzing the structure of these pronouns into their components. Its linguistic formulas are traced from the ancient Arabic texts, and by ancient I mean the texts of the era of linguistic ci
The study consisted in the development and use of a practical method to detect and
monitor, analyze and produce maps of changes in land use and land cover in the district of
Mahmudiya in Baghdad during the period 1990-2007 using the applications of remote sensing
techniques and with the assisstant of geographic information systems (GIS),as a valuable
contribution to land degradation studies.
This study is based maiuly on the processing on two subsets of landsat5 TM images picked up
in August 1990 and 2007 respectively in order to facilitate comparision and were thengeometrically and radiometrcally calibrated ,to used for digital classification purposes using
maximum liklihoods classification or six spectral bands of
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Incremental sheet forming (ISF) process offers a high degree of flexibility in the manufacturing of different sheet parts, which makes it an ideal candidate for prototype parts as well as efficient at fabricating various customized products at low production costs compared to traditionally used processes. However, parts produced in this process exhibit notable geometrical inaccuracy and considerable thickness reduction. In this paper, the single point incremental sheet forming variant of the process has been implemented to manufacture a highly customized cranial implant starting from the computed tomography (CT) scan data of the patient's anatomy. A methodology, from the modeling to the realization of the implant, is presented and discus
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