Aim To develop a low-density polyethylene–hydroxyapatite (HA-PE) composite with properties tailored to function as a potential root canal filling material. Methodology Hydroxyapatite and polyethylene mixed with strontium oxide as a radiopacifier were extruded from a single screw extruder fitted with an appropriate die to form fibres. The composition of the composite was optimized with clinical handling and placement in the canal being the prime consideration. The fibres were characterized using infrared spectroscopy (FTIR), and their thermal properties determined using differential scanning calorimetry (DSC). The tensile strength and elastic modulus of the composite fibres and gutta-percha were compared, dry and after 1 month storage in simulated body fluid (SBF), using a universal testing machine. The radiopacity of the fibres was determined using digital radiography. The interaction of the composites with eugenol was evaluated and compared with gutta-percha. Data of the tensile test were submitted to two-way anova and Bonferroni tests (P < 0.05). Results The endothermic peaks obtained from the DSC studies showed that the melting point of the HA/PE composites ranged between 110.5 and 111.2 °C, whereas gutta-percha exhibited a melting point at 52 °C. The tensile strength and elastic modulus of the silanated HA/PE composites were significantly higher than those of gutta-percha (P < 0.0001) under dry conditions and 1 month storage in SBF. The gutta-percha in eugenol showed a significant increase in the polymer molar mass, whereas the silanated HA/PE composites were unchanged. Radiological evaluations demonstrated that silanated HA/PE fibres were sufficiently radiopaque. Conclusion Promising materials for endodontic applications have been developed, offering relevant benefits over the traditional materials in terms of mechanical and chemical properties
Politeness strategies are of significant importance to maintain the face of the addressee. Senders of formal congratulatory letters seek to create a positive image in the minds of their addresses by performing particular illocutionary acts and face-saving acts (FSAs) in the form of written texts. To the best knowledge of the researcher, this topic received little attention from linguistic researchers, especially on the pragma-stylistic level. The importance of this study arises from the fact that congratulatory formal letters are an effective tool in the successful performance of foreign relations and thus deserve investigation. The current study investigates the pragmastylistic aspects of illocutionary acts and FSA Politeness Stra
... Show MoreBackground/Aim There is an association between patient general health, socioeconomic status and fracture incidence. Aim of this study was to demonstrate the relation between the socioeconomic and health status and the occurrence of fractures in Al-Kindy Hospital residents. Methods A prospective cross-sectional study was performed by using data collected from fractured patients in Al-Kindy Teaching Hospital / Baghdad Orthopaedics Outpatient Clinic, between 12 December 2021 and 8 March 2022. A hundred patients aged 20 to 75 years were included in this study. The data were collected using a researcher-administered questionnaire, which included items to assess patient's socioeconomic status (accommodations, occupation, income status, level of e
... Show MoreThe present project involves photodegrading the dye solochrom violet under advanced oxidation techniques at (25 oC) temperature and UV light. Zinc Oxide (ZnO) and UV radiation at a wavelength of 580 nm were used to conduct the photocatalytic reaction of the solochrom violet dye. One of the factors looked into was the impact of the starting conditions. pH, the amount of original hydrogen peroxide, and the dye concentration time radiation were used. For hours, the kinetics and percentages of degradation were examined at various intervals. In general, it has been discovered that the photodegradation rates of the dye were greater when H2O2 and ZnO were combined with UV light. The best wavelength to use was determined. Modern oxidation techni
... Show MoreThe Invar effect in 3D transition metal such as Ni and Mn, were prepared on a series composition of binary Ni1-xMnx system with x=0.3, 0.5, 0.8 by using powder metallurgy technique. In this work, the characterization of structural and thermal properties have been investigated experimentally by X-ray diffraction, thermal expansion coefficient and vibrating sample magnetometer (VSM) techniques. The results show that anonymously negative thermal expansion coefficient are changeable in the structure. The results were explained due to the instability relation between magnetic spins with lattice distortion on some of ferromagnetic metals.
Direct contact membrane distillation is an effective method for production of fresh water from saline water. In this study two samples were used as feed solutions; the first one was RO waste from Al-Hilla Coca-Cola Factory (TDS= 2382 mg/l) and the other was Haji Ali drainage water (TDS= 4127 mg/l). Polytetrafluoroethylene (PTFE) hydrophobic membrane supported with polypropylene (PP) was used as flat sheet form with plate and frame cell. Results proved that membrane distillation is an effective technique to produce fresh water with high quality from brine with low salinity content. With membrane area of 8x8 cm2, the volume of treated water decreased from 34.97 ml at first half hour to 33.02 ml after 180 min of
... Show MoreThe present study represent the histological and histochemical structure of the esophagus of laughing dove Streptopelia senegalensis, one of the wild birds, which feed on the seeds( grainvorous).The result showed that the esophagus long tubular quit wide and highly distensible organ situated at the right side of the nick , lie between pharynx and stomach it was divided into cervical and thoracic part , the cervical part longer than the thoracic part, and the crop was merely enlargement fusiform in shape which located at the entrance of the thorax. Esophagus parts showed that composed of four layer ;the mucosa, sub mucosa, muscular and adventitia or serosa, the mucosal layer was arranged in folds which was longer in the c
... Show MoreA.C electrical conductivity and dielectric properties for poly
(vinyl alcohol) (PVA) /poly (ethylene oxide) (PEO) blends undoped
and doped with multi-walled carbon nanotube (MWCNTs) with
different concentrations (1, and 3 wt %) in the frequency range
(25x103 - 5x106 Hz) were investigated. Samples of (PVA/PEO)
blends undoped and doped with MWCNTs were prepared using
casting technique. The electrical conductivity measurements showed
that σA.C is frequency dependent and obey the relation σA.C =Aωs for
undoped and doped blends with 1% MWCNTs, while it is frequency
independent with increases of MWCNTs content to 3%. The
exponent s showed proceeding increase with the increase of PEO
ratio (≥50%) for undope
Periodontitis is a chronic inflammatory disease resulted from aggravated immune response to a dysbiotic subgingival microbiota of a susceptible host. Consequences of periodontitis are not only limited to the devastating effect on the oral cavity but extends to affect general health of the individual and also exerts economic burdens on the health systems worldwide. Despite these serious outcomes of periodontitis; however, they are avoidable by early diagnosis with proper preventive measures or non-invasive interventions at earlier stages of the disease. Clinically, diagnosis of periodontitis could be overlooked due to certain limitations of the conventional diagnostic methods such as periodontal charting and radiographs. Utilization of re
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