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.
The 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
T.V photo in modern shows has emerged with special characteristics and signs that have developed in cope with the development of medium and technique. This leads to adding a variety of aesthetic dimensions which are capable of attracting audience because of its communicative elements that have an important role in increasing of T.V show Watching. As a result, the research is limited to methodological Framework as the problem. The problem of the research deals with emerging the aesthetic dimensions of T.V photo. The major question is (what are the aesthetic and communicative dimension of T.V Photo?). The research aims at finding out the aesthetic dimensions of T.V photo in modern artworks. The significance of the research on the presented
... Show MoreOne of the functions of Al-Shanasheel was to cool the air, but they could not compete with the Evaporative coolers, As Al-Shanasheel were a sign of luxury and wealth in Arab societies and were only built in homes of wealthy families, they are more expensive than the evaporative coolers, depending on the level of the decoration and the sculpting used to create them aesthetically, where People replaced them with evaporative coolers for their low cost, and higher cooling efficiency. One of the reasons for the disappearance of Al-Shanasheel is the absence of the functional need for them, in exchange for the high cost of construction. The diminished role of Al-Shanasheel in the contemporary urban scene, although they are one of the most
... Show MoreThis paper deals with aesthetic and a sitting position in contemporary Iraqi sculpture and studied this situation, an analytical study to reveal how to employ them in aesthetically pleasing work of art has been research in a sitting position to a lack of technical library for such research, this study includes four chaptersChapter I contains the research problem and its importance in terms of the released address and its objectives in the detection of this situation, how to employ the HDL research is to detect how the aesthetic of the Employment sit position and limits Find business is bronze and stone-dimensional exclusively carried out from 2000 to 2009 AD.Chapter II included the Framework theory and previous studies and with three Inv
... Show MoreLow cost Co-Precipitation method was used for Preparation of novel nickel oxide (NiO) nano particle thin films with Simple, with two different PH values 6, 12 and its effect on structural and optical properties as an active optical filter. Experimental results of structural properties X-ray diffraction (XRD) showed that both Nickel oxide nanoparticles with (PH=6 and 12) have polycrystalline structure smaller average particle size about 8.5 nm for PH=6 in comparison with PH=12. Morphological studies using Scanning electron microscopy (SEM) and atomic force microscope (AFM) show uniform nano rod distribution for PH=6 with smaller average diameter, average roughness as compared with NiO with
... Show MoreFaith is a feature of the Mesopotamian population, since the ancient Mesopotamian was a believer and obedient to his God in any case, and this encouraged the emergence of some of the phenomena interpreted by historians as an integral part of the civilization and ancient history of this country, and these phenomena are the phenomena of the deification of kings for themselves, The first phenomenon was a personal endeavor for the uniqueness of power, sometimes to correct some mistakes in societies to balance the state, and civil rule is independent of religious rule, and the second was the result of divination and predictions of omen, in the case of any bad harbinger of the king, such as the occurrence of eclipse To the sun or a lunar eclip
... Show MoreContemporary art has been widely affected by technology, and ceramics production is no exception. As an ancient art that originates from clay and other humble materials found in the ground, ceramics is considered one of the most adaptable art forms. Once it is realised how flexible ceramics as a material is, it can be easily altered into endless forms and shapes. Therefore, it is vital for ceramics practitioners to find a relationship between this wonderful material and the media of contemporary art, culture and modelling software or technology in general so that they can take their deformable art pieces to a whole new level. Such a relationship is worth investigating. Thus, for the purposes of this research, several ceramic pieces were
... Show More