Background: The integration of modern computer-aided design and manufacturing technologies in diagnosis, treatment planning, and appliance construction is changing the way in which orthodontic treatment is provided to patients. The aim of this study is to assess the validity of digital and rapid prototyped orthodontic study models as compared to their original stone models. Materials and methods: The sample of the study consisted of 30 study models with well-aligned, Angle Class I malocclusion. The models were digitized with desktop scanner to create digital models. Digital files were then converted to plastic physical casts using prototyping machine, which utilizes the fused deposition modeling technology. Polylactic acid polymer was chosen as the printing material. Twenty four linear measurements were taken from digital and prototyped models and were compared to their original stone models “the gold standardâ€, utilizing the paired sample t-test and Bland-Altman plots. Results: Eighteen of the twenty four variables showed non-significant differences when digital models were compared to stone models. The levels of agreement between the two methods showed that all differences were within the clinically accepted limits. For prototyped models, more than half of the variables differed in non-significant amount. The levels of agreement were also within the clinically accepted limits. Conclusion: Digital orthodontic study models are accurate in measuring the selected variables and they have the potential to replace conventional stone models. The selected rapid prototyping technique proved to be accurate in term of diagnosis and might be suitable for some appliance construction.
The aim of this work is to study the histological and histochemical structure of the Harderian gland in indigenous pigeons. Samples were obtained from 10 males and 10 females of adult healthy pigeons. Hematoxylin and eosin, Alcian blue (pH 2.5), periodic acid-Schiff and promo phenol blue, stains were used for paraffin section examination. The gland was teardrop like in shape, light brown to pink in color, capsulated with thin connective tissue. It was multilobular compound acinotubular in structure and lined by columnar epithelial cells. Lymphocyte, plasma cells and plasma cells with Russell bodies were present underneath the epithelia of central collecting duct and around the secretory unite. Histochemically; the
... Show MoreThe effect of micro-and nano silica particles (silica SiO2 (100 μm), Fused silica (12nm)) on some mechanical properties of epoxy resin was investigated (Young's modulus, Flexural strength). The micro-and nano composites were prepared by using three steps process with different volume fraction of micro-and nano particles (1, 2, 3, 4, 5, 7, 10, 15, and 20 vol. %). Flexural strength and Young's modulus of nano composites were increased at low volume fraction (max. enhancement at 4 vol.% ). However at higher volume fraction both Young's modulus and flexural strength decrease. Moreover, above, the mechanical properties are enhanced more than that of neat epoxy resin. The flexural strength decreases with increasing the volume fraction of micr
... Show MoreNanocomposite was prepared using unsaturated polyester (UP) resin as a matrix and graphene nanoparticles as a reinforcement material in six percentage weights (0, 0.1, 0.2, 0.3, 1 and 1.5%). Mechanical, calorimetric and thermal studies were performed on the (UP) resin/graphene nanocomposite. All tests showed a clear improvement of all mechanical properties examined (hardness, flexural strength (F.S), impact strength (I.S) and tensile strength (T.S)) with increasing graphene percentage. In addition, the temperature of glass transition and thermal conductivity of this composite increased with increasing graphene content.
1-Alglul is the introduction of after prize or (Booty) secretly before it is divided, and the general sense is an absolute betrayal, and God has forbidden and the Prophet (Peace be upon him) by Muslims; such as bribery and gift-giving and other function by the terminology.
2-The signals and texts Alglul in the Covenant Rashidi and the Umayyad and Abbasid very few, compared to the Covenant of the Prophet, and so by the Quranic verses that were deprived Alglul and other Transmitting booty for the Muslims, and the hadith which magnified Alglul and showed its consequences in this life and the afterlife, and the tutelage of the Prophet (Peace be upon him) its active role in reducing Alglul, it was the great commandments included notificati
Amoxicillin have been conjugated with metronidazole as possible mutual prodrug to get a wider spectrum of activity by acting on aerobic and anaerobic bacteria, have antifungal activity, to provide protection for beta lactam ring of amoxicillin and also to improve patient compliance as it given as a single dose therapy. The structures of the synthesized compound were confirmed and characterized using elemental microanalysis (CHN), IR and some physiochemical properties. Biological study was done by using disc diffusion method against different bacterial strains which are , Staphylococcus aureus , Salmonella typhie , Pseudomonas aeruginosa , E. coli , Klebsiella pneumonia and fungi ( Candida albicans) . using nutrien
... Show Moreraisin on mice in comparison with negative (phosphate buffer saline (PBS) and positive Mitomycin-C (MMC) controls. Moreover, the effect on fertility hormones (follicles stimulation hormone/FSH, lutenising hormone/LH) was also measured. The effect of the extracted samples were measured by employing cytogenetic analysis which included (the mitotic index (MI), chromosomal aberrations (CAs) and micronucleus (MN)) parameters. Results showed that significant increase in MI and significant reduction in both CAs and MN percentage were seen after treatment with both alcoholic and water extracts of the two raisins and alcoholic extracts was more effective than water extracts. On the other hand both the gold and black raisin enhanced the levels of the
... Show MoreIn this study, aromatic polyamide reverse osmosis membranes were used to remove zinc ions from electroplating wastewater. Influence of different operating conditions such as time, zinc concentration and pressure on reverse osmosis process efficiency was studied. The experimental results showed, concentration of zinc in permeate increase with increases of time from 0 to 70 min, and flux of water through membrane decline with time. While, the concentrations of zinc in permeate increase with the increase in feed zinc concentration (10–300 mg/l), flux decrease with the increment of feed concentration. The raise of pressure from 1 to 4 bar, the zinc concentration decreases and the flux increase. The highest recovery percentage was fou
... Show MoreThe Logic of Freezers and Animals in the Holy Quran
Cerium oxide CeO2, or ceria, has gained increasing interest owing to its excellent catalytic applications. Under the framework of density functional theory (DFT), this contribution demonstrates the effect that introducing the element nickel (Ni) into the ceria lattice has on its electronic, structural, and optical characteristics. Electronic density of states (DOSs) analysis shows that Ni integration leads to a shrinkage of Ce 4f states and improvement of Ni 3d states in the bottom of the conduction band. Furthermore, the calculated optical absorption spectra of an Ni-doped CeO2 system shifts towards longer visible light and infrared regions. Results indicate that Ni-doping a CeO2 system would result in a decrease of the band gap. Finally,
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