Background: Masseter muscle is one of the most obvious muscles of mastication and considered as one indicator of jaw muscle activity. It has a major influence on the transverse growth of the midface and the vertical growth of the mandible. This study undertaken to determine the role of cephalometric analysis for discrimination between Cl I and Cl III skeletal relationships, determine the role of ultrasonography in determination of masseter muscle thickness, compare masseter muscle thickness between Cl I and Cl III skeletal relationships, and determine the effect of gender on masseter muscle thickness. Material and Method: The sample of the current study consisted of 70 Iraqi subjects 40 males and 30 females with age ranging 18-25 years. They were divided into 2 groups depending on ANB angle: class I skeletal relationship 20 males and 15 females and class III skeletal relationship 20 males and 15 females. The collected sample included patients attended for different diagnostic purposes to the Dental Radiology Department at College of Dentistry/Babylon University, standardized lateral cephalogram was taken to determine facial morphology, six angular and eight linear measurements were assessed. Masseter muscle thickness measured ultrasonography in Al-Hilla General Teaching Hospital/Ultrasonorgaphic Department, in relaxation and contraction conditions for both sides. Results: Various parameters measured for males and females in each class and the comparison shown statistically significant differences between them (P<0.05). No difference in muscle thickness between right and left sides in the same class (P>0.05). Gender variation showed significant difference in masseter muscle thickness during rest and occlusion conditions (P<0.001). Conclusion: Cephalometric analysis served to demonstrate the skeletal morphologies and provide a base for discrimination between class I and class III skeletal relationships. Ultrasonographic scanning is an important imaging procedure. It is reproducible and simple method for accurately measuring masseter muscle thickness. The ultrasonorgaphic study has revealed variations in masseter muscle thickness among individuals with different skeletal morphologies in each gender on one hand and between males and females in each skeletal class on the other hand. Key words: Masseter muscle thickness, skeletal morphology, cephalometric analysis, ultrasonorgaphic scanning.
Cloud point extraction is a simple, safe, and environmentally friendly technique for preparing many different kinds of samples. In this review, we discussed the CPE method and how to apply it to our environmental sample data. We also spoke about the benefits, problems, and likely developments in CPE. This process received a great deal of attention during preconcentration and extraction. It was used as a disconnection and follow-up improvement system before the natural mixtures (nutrients, polybrominated biphenyl ethers, pesticides, polycyclic sweet-smelling hydrocarbons, polychlorinated compounds, and fragrant amines) and inorganic mixtures were examined and many metals like (silver, lead, cadmium, mercury, and so on). We also find
... Show MoreThe effect of different cutting fluids on surface roughness of brass alloy workpiece during turning operation was carried out in this research. This was performed with different cutting speed, while other cutting parameters had been regarded as constants(feeding rate , and depth of cut). Surface roughness of machined parts that will be tested by electronic surface roughness tester .The results show that the standard coolant gives the best values of surface roughness for fixed cutting speed ,followed by sun flower oil that has approximately the same effect, while the air stream as a coolant gave unsatisfied results for the evaluation of surface roughness.
In the other hand the best values of surface roughness were recorded for max
... Show MoreObjective. This study aimed to evaluate and compare the force degradation of two types of elastomeric chains following different periods of immersion in zinc-containing mouthwashes. Materials and Methods. Four hundred and forty pieces of Elasto-Force and Super Elasto-Force elastomeric chains were divided into two control and eight experimental groups. The pieces were stretched to 25 mm on pins mounted on an acrylic block and stored in distilled water at 37°C. The experimental groups were immersed in four different types of mouthwash for one minute twice a day throughout the test period. Ten continuous thermocycles per day between cold and hot water baths (5–55°C) were carried out. Forces were measured at six-time intervals (in
... Show MoreIn this research we study a variance component model, Which is the one of the most important models widely used in the analysis of the data, this model is one type of a multilevel models, and it is considered as linear models , there are three types of linear variance component models ,Fixed effect of linear variance component model, Random effect of linear variance component model and Mixed effect of linear variance component model . In this paper we will examine the model of mixed effect of linear variance component model with one –way random effect ,and the mixed model is a mixture of fixed effect and random effect in the same model, where it contains the parameter (μ) and treatment effect (τi ) which has
... Show MoreThe root lesion nematode, Pratylenchus neglectus, is one of the most damaging nematodes to affect wheat worldwide. The nematode is widely distributed in Montana, primarily affecting winter wheat within the state. Managing the nematode primarily involves rotation to resistant and moderately resistant crops (peas, lentils, and barley). A nematode survey was conducted across the state nearly 10 years after an initial survey, to reassess the nematode threat and assess the impact of changing trends in crop rotations. To assess the broad applicability of rotation crops to control P. neglectus across Montana, greenhouse trials were conducted to challenge rotational crops using eight populations of P. neglectus collected from geographicall
... Show MoreThe preparation of the title compound, C26H25N, was achieved by the condensation of an ethanolic mixture of benzaldehyde, cyclohexanone and ammonium acetate in a 2:1:1 molar ratio. There are two crystallographically independent molecules in the asymmetric unit. The two cyclohexyl rings adopt an
The study aimed at identifying youth and sport forums from planning and leadership point of view and their relation with organizational culture. The researchers used the descriptive method on (140) worker in Baghdad youth and sport forums. A scale was designed for measuring planning and leadership in youth and sport forums as well as designing a scale for measuring organizational culture. After the application of the main experiment, the results showed that both youth and sport forum administration scale and organizational culture scale are appropriate to the study community. Finally the researchers recommended using these scales by workers in youth and sport forums and involving administration mangers in periodical training courses
... Show MoreAn increasing number of emerging contaminants have been detected in surface waters, sediment, soil and ground water in different locations in the world, which is a new environmental challenges need an actual concern for international scientific and legislative communities.
The nonprescription and huge used pharmaceuticals ibuprofen and diclofenac sodium will be focused in this study. New adsorbent developed using cheap inorganic clay material (bentonite) and organic polymer polyureaformaldehyde (PUF), the combination of these two materials gave the surface more roughness with wide active site distribution. Batch adsorption experiment performed to each pharmaceutical individually to determine the optimum separat
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