Background: The demand for better esthetic during orthodontic treatment has increased nowadays, so orthodontists starting using esthetic arch wires, brackets and ligatures.Tooth colored brackets were introduced in different types of materials. Sapphire ceramic brackets are one type of esthetic brackets and their color stability remains the main concern for the clinicians and patients at the same time. The present study design to evaluate the effect of three different staining materials (pepsi, black tea and cigarette smoke) on the stainability of sapphire ceramic brackets bonded with three types of light cure orthodontic adhesives which include: Resilience, Enlight and Transbond. Materials and Methods: The sample consisted of three hundred sixty sapphire brackets. The brackets were divided according to bonding materials into three groups each group consist of one hundred twenty brackets, then each subgroup farther subdivided into four groups according to the material they were immersed (distilled water, black tea, Pepsi and cigarette smoke) with thirty brackets each, then Each group with ten brackets farther subdivided according to time interval of immersion in each media into three groups one day, seven days and fourteen days at 37°C in the incubator.A UV-Visible spectrophotometer (Shimadzu, UV -1800) was used to perform a light absorption test. Results: ANOVA and LSD post Hoc tests were used to identify the significant effects of the staining materials at a significance level P ≤ 0.05.It was found that the immersion time gradually influenced the color stability of the adhesive materials with sapphire brackets with the highest activity observed at fourteen days interval. The brackets bonded with Resilience light cure adhesive are the most type affected by staining materials, then followed by the brackets bonded with Transbond and finally the brackets bonded with Enlight light cure adhesive. For the staining materials it was found that the cigarette smoke is the most powerful staining material, followed by tea and finally pepsi. Conclusions: From the above result we can conclude that the type of adhesive must take in consideration when the esthetic brackets have been used.
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10 sites were selected for investigating zebra mussels in the Tigris River for the study that was conducted for the period from January to December 2020. The results of this investigation showed that zebra mussels were recorded in the Tigris at Taji on sites 7, 8, 9 and 10, while it was not found in the Tigris at Kut on sites 1, 2, 3, 4, 5 and 6. This is the first time that this species was ever recorded in the Tigris. It was found that the sites where zebra mussels appeared had a clear impact on the decrease in the total organic carbon %age and turbidity (NTU). High dissolved oxygen values were observed in the sites where zebra mussels were recorded, and the appearance of zebra mussels in these sites caused a clear decrease in
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The Impact of Intellectual trends on the nature of the Economic Structure of Iraq
The study aims to identify the mechanical and electrical activities of the heart according to the energy systems of advanced players and to detect the differences between the energy systems in terms of the mechanical and electrical activities of the heart for advanced players. It was clear from the results of the significance of the differences between the three groups according to the energy systems of the advanced players in all research variables that (the non-oxygenic system "Lactic"), which represents the advanced players in the arches (800 m, 1500 m) was the first in most tests of mechanical and electrical activities of the heart, which is (Margaria-Kalamen, Wingate, systolic muscle strength of the heart FC, Stroke Volume SV
... Show MoreIn this research, optical absorption data (the imaginary part of the dielectric function Ɛ2 as a function of photon energy E) were re-analyzed for three samples of a-Si:H thin films using derivative methods trying to investigate the ambiguity that accompany the interpretation of the optical data of these film in order to obtainm the optical energy gap (Eg) and the factor (r) which in concerned with the density of state distribution near the mobility edge directly without the need for a pre- assumption for the factor r usually followed in traditional methods such as the Tauc plot. The derivative method was used for two choices for the factor q (which in connected with the dependence of the dipole matrix element on the photon energy ) for
... Show Morethe student of the structure of the city and its constituent elements will clearly sense the invisible relationships that underlie the different forms of urban activity, which in turn are defined by the generality of the urban patterns in that city, which will vary clearly according to the location in the city. These relations will be embodied in their true form in the interactions between the different uses of the earth, and the change that will result from their regularity in the form of entities in independent groups, which may share with each other a component of it.
Therefore, the process of controlling the functional interactions between the uses of the urban land and the awareness of t
Objectives To compare the clinical efficacy of microvascular decompression surgery (MVD) and gamma knife radiosurgery (GKR) as a treatment for patients with primary trigeminal neuralgia (TN) and evaluate the outcome regarding pain relief, recurrence, and complications with both modalities of treatment. Patients and Methods A randomized prospective study conducted in SaadAlwitry Neurosciences Hospital, Baghdad, Iraq. Eighty-four patients with TN from January 2016 to January 2018, 45 patients had GKR while 39 patients treated with MVD. The pain evaluated pre-and post-operatively using the Barrow Neurological Institute Pain Intensity scale (BNIPI), visual analog scale (VAS) and Brief Pain Inventory Facial (BPI-Facial) scoring systems. In GKR p
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