Objectives To tailor composites of polyethylene–hydroxyapatite to function as a new intracanal post for the restoration of endodontically treated teeth (ETT). Methods Silanated hydroxyapatite (HA) and zirconium dioxide (ZrO2) filled low-density polyethylene (LDPE) composites were fabricated by a melt extrusion process and characterised using infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA). The flexural strength and modulus were determined in dry state and post ageing in simulated body fluid and fractured surfaces analysed by SEM. The water uptake and radiographic appearance of the experimental composites were also measured and compared with a commercially known endodontic fibre post. Data were submitted to one-way analysis of variance (ANOVA) and post hoc Tukey multiple comparison tests at a level of significance P < 0.05. Results The LDPE/HA composites were structurally flexible and the HA content had a significant effect on the flexural strength and modulus. A univariate analysis of variance showed no significant differences in modulus and strength (P < 0.05) post accelerated ageing in simulated body fluid with very low water uptake. The melting point of the LDPE/HA composites ranged between 135 and 136 °C, which would facilitate removal in case of retreatment using conventional dental heating devices. The inclusion of HA reduced the damping thereby enhancing dimensional stability, whilst the addition of zirconia yielded a semi-translucent material that was sufficiently radiopaque, comparable to commercial posts, thus yielding aesthetic materials. Conclusions Innovative materials for restoration of ETT were developed; offering considerable benefits over the currently available material in terms of biomechanical and thermal properties. Clinical significance This study provided a new option for the development of a new intracanal post made up of functional and aesthetic composites.
This study examines patterns of exposure of Iraqi university students to selective daily Iraqi newspapers and the motives of this exposure, as well as its associated factors that affect the average exposure. It tries to answer several questions, including those related to the levels of exposure of Iraqi university students to daily Iraqi newspapers and classification of patterns of selective exposure to daily Iraqi newspapers and the most prominent Iraqi daily newspapers that are selectively exposed by Iraqi university students. It also examines the motives of this selective exposure and factors that increase the degree of exposure to the daily Iraqi newspapers, and the most prominent stages in which Iraqi university students find their
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The aim of the current research is to identify the Effect of the alternative evaluation strategy on the achievement of fourth-grade female students in the subject of biology. The researchers adopted the zero hypothesis to prove the research objectives, which is there is no statistically significant difference at the level (0.05) between the average scores of the experimental group who study according to the alternative evaluation strategy and the average scores of the control group who study in accordance with the traditional method. The researchers selected the experimental partial adjustment design of the experimental and control groups with the post-test. The researchers intentionally selected (Al-fed
... Show MoreThis research aims to evaluate the teaching methods used by intermediate Arabic language teachers. To achieve the goal, the researcher followed the descriptive-analytical approach. The research sample was limited to Arabic language teachers at intermediate school for the academic year (2017-2018) the researcher chose a random sample included (155) teachers which form a (40%) Of the original community at Baghdad/ Rusafa1th. The researcher has developed standards of teaching methods which are (7) standards with (39) paragraphs included three alternatives. The results showed the need to pay attention to the use of various modern teaching methods. Moreover, the researcher suggested making an evaluation of the teaching methods used by Arabic
... Show MoreThe aim of the current research is to study a topic from the Qur’anic topics, few have researched it and realized its content, so people knew it in one name in the Qur’an in another name, and due to the ancientity of the topic and its contemporaneity, I wanted to write about it. The research has an introduction, three demands, and a conclusion with the most important results of the research:
As for the introduction: It was to indicate the importance of the topic and an optional reason for it.
As for the first requirement: it included the definition of reasoning, its divisions, and its characteristics.
As for the second requirement, it was to indicate the meaning, types, and methods of labeling it.
As for the third require
Walkability as one of the Planning Treatments to Face Epidemics in Cities
The emergence of artistic movements in Western countries was after the period of modernity. They have introduced a great dialectical problem at the level of thought and discourse, which necessitated a change in the course of the aesthetic discourse into new visions. Thus, the present research aims to identify the aesthetic discourse of pop artists' Art and its representations in the outputs of the students of the Department of Art Education. The theoretical framework included two sections: the first one, what is the aesthetic discourse and the second is the educational bases of the students' outputs. The procedures of the current research included the analytical descriptive approach. The research sample consisted of (4) outputs chosen ac
... Show MoreThis study has been developed axes of the search, including: Search (deliberative) language and idiomatically, and Description Language (b social phenomenon), and the definition of the theory of (acts of speech), and discussed the problem of the conflict between tradition and innovation, as defined objectively have a target aimed at reviving the deliberative thought when Arab scholars , and the balance between the actual done Arab and Western rhetoric, but Meet in intellectual necessity, a sober reading that preserve the Arab language prestige, and its position in the light of the growing tongue Sciences, as long as we have inherited minds unique, and heritage huge able to consolidate the Arab theory lingual in linguistics.
With the growing number of Internet users, public and private arts activities have become increasingly popular. Adolescents have begun to establish aesthetic taste and new cultural values. This category is the most affected one by the published images and ideas especially in the social networking space and specifically the Facebook. It is the most important problem in their cultural composition. This research aims to detect the problems of social networking sites in nurturing the aesthetic taste of adolescents. The researcher used the analytical descriptive approach to obtain accurate information describing the current situation or depicting the social reality of adolescents. The research concluded that the public discourse in social med
... Show MorePolymers, being one of the most important materials in dentistry, offer great physical and mechanical qualities, as well as good biocompatibility. Aim of this study was done to evaluate the Polyetherketoneketone and Polyetherketoneketone polymer composite material used as dental implant through tensile strength, Fourier Transform Infrared analysis FTIR, and wettability). Polyetherketoneketone composites (Polyetherketoneketone and Strontium-containing hydroxyapatite) with selected weight percentage ratios of (0, 10%, 20%, 30%), were fabricated using a compression molding technique”, The study involved Samples preparation (sheets) shaped and form into the desired shape according to standard for tests which included tensile strength,
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