Background: Complete removal of filling material from the root canal is an essential requirement for endodontic retreatment. The purpose of the present study is to evaluate and compare the dissolving capabilities of various solvents (Xylene, Eugenate Desobturator, Eucalyptol, EDTA and Distilled water (as a control)) on four different types of sealer (Endofill, Apexit Plus, AH Plus and EndoSequence bioceramic sealer). Materials and method: Eighty samples of each sealer were prepared according to the manufacturers' instructions and then divided into ten groups (of 8 samples) for immersion in the respective solvents for 2 and 5 min immersion periods. Each sealer specimen was weighed to obtain its initial mass. The specimens were immersed in the tested solvents for 2 and 5 min, followed by rinsing with double distilled water and blotted dry with an absorbent paper, then they were reweighed to determine its final mass. The mean of weight loss was determined for each material in each solvent during the specified immersion period, and the values were subjected to statistical analysis. Results: Clear differences were shown in the solubility profile of these root canal sealers in the tested solvents. The result of the present study shows that Xylene had the greatest capacity for dissolving Endofill, Apexit Plus and AH Plus. Eugenate Desobturator, Eucalyptol and EDTA showed a highly significant dissolving capability on these sealers with variations between these subgroups; EndoSequence BC sealer is insoluble in these tested solvents. Regarding the immersion time, higher values of solubility were obtained at 5 min than that at 2 min immersion time. Conclusion: The results showed that Xylene, Eugenate Desobturator, Eucalyptol and EDTA can be used for the removal of Endofill, Apexit Plus and AH Plus during endodontic retreatment with variations between these subgroups; D.W (control group) showed the least capacity for dissolving these sealers. EndoSequence BC sealer is insoluble in the tested solvents.
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Polymeric hollow fiber membrane is produced by a physical process called wet or dry/wet phase inversion; a technique includes many steps and depends on different factors (starting from selecting materials, end with post-treatment of hollow fiber membrane locally manufactured). This review highlights the most significant factors that affect and control the characterization and structure of ultrafiltration hollow fiber membranes used in different applications.
Three different types of polymers (polysulfone PSF, polyethersulfone PES or polyvinyl chloride PVC) were considered to study morphology change and structure of hollow fiber membranes in this review. These hollow fiber membranes were manufactured with different pro
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One of the most important , compound which have active hydrogen is the compound possessing (thiol group) Biphenyl-4,4-dithiol is agood example utilized in a wide field for preparation mannich bases , avariety of new acetylenic mannich bases have been Synthesized and all proposed structure were Supported by FTIR , 1H – NMR, 13C-NMR , Elemental analysis and microbial study .
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Tin Selenide (SnSe) Nano crystalline thin films of thickness 400±20 nm were deposited on glass substrate by thermal evaporation technique at R.T under a vacuum of ∼ 2 × 10− 5 mbar to study the effect of annealing temperatures (as-deposited, 100, 150 and 200) °C on its structural, surface morphology and optical properties. The films structure was characterized using X-ray diffraction (XRD) which showed that all the films have polycrystalline in nature and orthorhombic structure, with the preferred orientation along the (111) plane. These films was synthesized of very fine crystallites size of (14.8-24.5) nm, the effect of annealing temperatures on the cell parameters, crystallite size and dislocation density were observed.
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