Background: The bond strength of the root canal sealers to dentin is very important property for maintaining the integrity and the seal of root canal filling. The aim of this study was to evaluate and compare the push-out bond strength of root filled with total fill Bioceramic, AH Plus and Gutta-flow®2 sealers using GuttaFusion®obturation system versus single cone obturation technique. Materials and method: sixty of mandibular premolars teeth with straight roots were used in this study, these roots were instrumented using Reciproc system, instrumentation were done with copious irrigation of 3 mL 5.25% sodium hypochlorite solution (NaOCl) during all the steps of preparation, and smear layer will be removed with 1 ml of 17% EDTA kept in the canal for 1 min, roots were randomly divided into two groups according to the obturation technique (thirty teeth for each group): Group I: Single Reciproc Gutta percha cone obturation technique, Group II: Gutta fusion obturation technique, then each group divided into three subgroup according to the type of sealer, AH subgroup: AH Plus sealer, BC subgroup: bioceramic sealer and GF subgroup: Gutta flow 2 sealer. The roots then stored in moist environment at 37°C for one week, the roots were embedded in clear acrylic resin and each root sectioned into three levels apical, middle and cervical. The bond strength was measured using computerized universal testing machine each section fixed in the machine so that the load applied from apical to cervical direction at 0.5mm/min. speed and the computer show the higher bond force before dislodgment of the filling material. These forces were divided by the surface area to obtain the bond strength in MPa. Results: Statistical analysis was performed and the result showed a highly significant differences between the three types of sealers when the same obturation technique were used, also there is highly significant differences between two groups with two different obturation technique. Conclusion: This study showed that the push out bond strength of AH plus sealer was higher than bioceramic sealer and Gutta flow 2 sealer respectively when the same obturation technique was used. The push out bond strength was affected by the obturation technique and Gutta fusion obturation technique showed higher bond strength than single cone obturation technique when the same type of sealer was used.
In this paper the method of singular value decomposition is used to estimate the ridge parameter of ridge regression estimator which is an alternative to ordinary least squares estimator when the general linear regression model suffer from near multicollinearity.
Global Navigation Satellite System (GNSS) is considered to be one of the most crucial tools for different applications, i.e. transportation, geographic information systems, mobile satellite communications, and others. Without a doubt, the GNSS has been widely employed for different scientific applications, such as land surveying, mapping, and precise monitoring for huge structures, etc. Thus, an intense competitive has appeared between companies which produce geodetic GNSS hardware devices to meet all the requirements of GNSS communities. This study aims to assess the performance of different GNSS receivers to provide reliable positions. In this study, three different receivers, which are produced by different manufactur
... Show MoreVenus orbit around the Sun is an ellipse inside the Earth orbit. The elements of Venus orbit and its position are affected by the gravitational force of near planets therefore the elements were determined with Julian date through ten years 2011-2020. The orbital elements used to calculate Venus distance from the Sun, the heliocentric and geocentric equatorial coordinates. From the results the orbit of Venus and its position were described and show the gravity effect of near planets on it. The results get the values and their variation through ten years for the eccentricity, semi-major axis, inclination, longitude of ascending node, argument of perihelion, mean anomaly and distance from the Sun. The variation is very small through 10 year
... Show MoreThe traditional city suffers from the decline of the urban image due to urban development and homogeneity with the urban context of the city, and because of the lack of determinants governing the urban image, it is that the center of the city of traditional Kadhimiya suffers from a break in the urban image, Therefore, the research included how to build a distinctive urban image of the center of the traditional city of Kadhimiya and achieve the visual pleasure and comfort of the recipient and the urban image here means is an image not picture which are related to several aspects, including physical, social and psychological as well as the collective memory of individuals and their rela
The concepts of nonlinear mixed summable families and maps for the spaces that only non-void sets are developed. Several characterizations of the corresponding concepts are achieved and the proof for a general Pietsch Domination-type theorem is established. Furthermore, this work has presented plenty of composition and inclusion results between different classes of mappings in the abstract settings. Finally, a generalized notation of mixing maps and their characteristics are extended to a more general setting.
Most of the theorists and researchers and also those interested in cinema and television attributed the fact of the existence of the dramatic works to the directors may be due to a historical justification. At the same time, the existence of the production world came as a result of the emergence of the production city (Hollywood). This is also a historic fact. The research would tackle all the formative truths to prove the relation and the timeline, i.e., before and after and the synergy that resulted in the existence of the dramatic works that benefited the humanity and those interested in this giving art. The objective of the research is to uncover the formative truth of the dramatic work between direction and production.
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... Show MoreReservoir study has been developed in order to get a full interesting of the Nahr Umr formation in Ratawi oil field. Oil in place has been calculated for Nahr Umr which was 2981.37 MM BBL. Several runs have been performed to get matching between measured and calculated of oil production data and well test pressure. In order to get the optimum performance of Nahr Umr many strategies have been proposed in this study where vertical and horizontal wells were involved in addition to different production rates. The reservoir was first assumed to be developed with vertical wells only using production rate of (80000–125000) STB/day. The reservoir is also proposed to produce using horizontal wells besides vertical wells with pr
... Show MoreThere is no adopt in the importance of the optical communications in scientific civil and military applications because of it’s simplicity in manufacturing and it's low cost. The method of optical communication depends upon bearing the light beam the translated informations by a method called the light modulation. This method depends upon changing some light properties as frequency, amplitude and pulse duration according to the translating informations. The changes in the first two properties are concerned optically with the analog modulation while the third one concern at most with digital modulation. All past methods are expensive with low efficiency and needs electrical or magnetic fields. In this technique the source of voice used
... Show MoreThe propaganda discourse is the most widely circulated in the media and communication studies, where the interest of scholars and researchers in this field has become clear in the analysis and interpretation of the content of this discourse, to identify the intentions, purposes and objectives of the communicator activity, which exceeded the borders of states in the heated atmosphere of rivalries and political conflicts that characterize The countries of the world as a whole and for many years.
In particular, the economically and militarily developed countries (the Nordic capitalist countries) have exerted special efforts in the production of information and ideas, using advanced methods and means in all details of communication w
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