Background: Many types of instruments and techniques are used in the instrumentation of the root canal system. These instruments and techniques may extrude debris beyond the apical foramen and may cause post-instrumentation complications. The aim of this study was to evaluate the amount of apically extruded debris resulted by using 4 types of nickel-titanium instruments (WaveOne, TRUShape 3D conforming files, Hyflex CM, and One Shape files) during endodontic instrumentation. Materials and methods: Forty freshly extracted human mandibular second premolar with straight canals and a single apex were collected for this study. All teeth were cut to similar lengths. Pre-weighted glass vials were used as collecting containers. Samples were randomly divided into four groups with 10 samples in each group: Group A instrumentation by WaveOne reciprocating file, Group B instrumentation by TRUShape 3D rotating files, Group C instrumentation by Hyflex CM rotating files and Group D instrumentation by One Shape rotating file. A total volume of 7 ml of sodium hypochlorite was used for irrigation in each sample. Apical patency confirmed and maintained by a size #15 K-File. All canals were instrumented up to a size #25. After completion of endodontic instrumentation, vials were then stored in an incubator for 5 days at 68o C for dryness. Then vials are weighted again, and the pre-weight subtracted from the post-weight, the weight difference resembled the amount of apically extruded debris from the apical foramen during root canal instrumentation. Data obtained were statistically analysed by using ANOVA and LSD tests. Results: The results showed that the Hyflex CM Group (C) has statistical significant lowest apically extruded debris as compared to other groups of this study (P ≤0.05), while the TRUShape Group (B) has statistical significant lowest apically extruded debris as compared to One Shape Group (D) and WaveOne Group (A), while the WaveOne Group (A) showed the highest value of apically extruded debris (p ≤0.01). The result showed that all groups resulted in apical extrusion of debris. Significance: Although all systems caused apical extrusion of debris and irrigant, continuous rotary instrumentation was associated with less extrusion as compared with the use of reciprocating file system.
The present research was carried out to assess the toxic effect of oral administration of the aqueous extract of Nerium oleander leaves and flowers daily at doses of (25) mg/kg body weight for four weeks in mice. The toxicity of this plant parts was determined after two and four weeks by measuring the parameters of cytogenetic (mitotic index, micronucleus %), and serum levels of the hematological (RBC, Hb, WBC) and biochemical (GOT, GPT, ALT, AST) indexes in comparison with that of the control (normal saline), also clinical signs were determined. The results showed a significant decrease in mitotic index while an obvious raise was seen in micronucleus percentage in comparison with that of the control after the two periods of admini
... Show MoreThis study aims at identifying how Baghdad Municipality employs public relations in law enforcement operations and the role played by the Municipality in communication and communicating with the public, raising their awareness and educating them to not abuse public property. As for the research tools, the researcher used the questionnaire as a data collection tool in addition to an analytical description of the means and methods of communication for public relations on Baghdad Municipality Facebook page.
The research comes out with a set of result; the most important of which are:
The means through which citizens learned about the existence of campaigns to impose the law an eliminate violati
Idioms are a very important part of the English language: you are told that if you want to go far (succeed) you should pull your socks up (make a serious effort to improve your behaviour, the quality of your work, etc.) and use your grey matter (brain).1 Learning and translating idioms have always been very difficult for foreign language learners. The present paper explores some of the reasons why English idiomatic expressions are difficult to learn and translate. It is not the aim of this paper to attempt a comprehensive survey of the vast amount of material that has appeared on idioms in Adams and Kuder (1984), Alexander (1984), Dixon (1983), Kirkpatrick (2001), Langlotz (2006), McCarthy and O'Dell (2002), and Wray (2002), among others
... Show MoreOne of the most important challenges facing the development of laser weapons is represented by the attenuation of the laser beam as it passed through the layers of atmosphere.This paper presents a theoretical study to simulate the effect of turbulence attenuation and calculates the decrease of laser power in Iraq. The refractive index structure C_n^2 is very important parameter to measure the strength of the atmospheric turbulence, which is affected by microclimate conditions, propagation path, season and time in the day. The results of measurements and predictions are based on the Kolmogorov turbulence theory. It was demonstrated by simulations that the laser weapons in Iraq were severely affected due to the large change in temperatures,
... Show MoreMagnesium oxide nanoparticles were synthesized via a co-precipitation procedure. Comprehensive characterization included infrared fluorescence, X-ray scattering spectroscopy, scanning electron microscopy, as well as X-ray diffraction and atomic force microscopy. Surface properties were analyzed using Langmuir, Brunauer -Emmett-Teller, Barrett–Joyner–Halenda, t-plot techniques, and the N2 adsorption-desorption isotherms methods to determine surface area and pore structure. Results confirmed the nanoparticles possess high purity. The size of the synthesized particles ranged from 30-40 nm, which was determined by scanning electron microscopy. The surface area of the prepared particles is 31,227 m2 g-1, and it was found that the por
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