Background:Open reduction and internal fixation (ORIF) of using miniplates and screws is the treatment of choice of mandibular fractures. It is important to know both: the region where the bone providesafirm anchorage, andthe topography of the dental apices and inferior alveolar nerve to avoiddamaging them when inserting the screw. The aim of this study is to determine the thickness of buccal cortical plate and that of buccal bone at the parasymphysis and mandibular body, thereby determining the area that provide afirm anchorage and the maximum length of mono-cortical screws that can be safely placed in these regions without injuring the tooth roots or mandibular nerve. Materials and Methods:The sample of the present study was 110 Iraqi subjects (77 males & 33 females) aged (18-35) years old who admitted to Computed Tomography scan unit in AL-Sadr Teaching Hospital in Al-Najaf city to get Computed Tomographic examination of facial bones. The conventional sections of CT (axial, coronal) used to do the measurements and dental planning analysis also used. The thickness of buccal cortical plate and the thickness of buccal bone were measured at the level of root apex of (canine, first premolar, second premolar) and at the level ofroot apex and inferior alveolar canal in mesial and distal root of first and second molar. Results:There was no statistical significant difference in buccal cortical plate and buccal bone thickness between age and gender at most measured sites. Using of 4mm screw is safe in distal root region of 2nd molar at the level of apex and that of inferior alveolar canal for both males and females. Moving slightly forward in position to the mesial root of 2nd molar 1mm will be lost from safety margin, while making only the 3mm screw is safe. For the remaining anterior positions only the minimum screw length of 2 mm is safe. Conclusions:Thickness of buccal cortical plate and buccal bone in various sites could be measured precisely using Multislice Computed tomography which can guide surgeons in selecting the proper screw length without causing injury to tooth apex or inferior alveolar nerve.
Optimization of well placement plays a considerable role in the production and maximizing the net present value of the investment of oil field developments. However, the application of the optimization techniques in well placement developments is so complicated because many decision variables, objective functions, and constraints are involved in the well placement optimization case. Furthermore, many computational techniques; conventional and non-conventional, have been utilized to optimize well placement operations. This study displays the advancement of the optimization methods applied in the well placement. Subsequently, the study assorted the applied optimization methods, and it demonstrates the restriction and the range of implementati
... Show MoreFlexible pavement design and analysis were carried out in the past with semi-experimental methods, using elastic characteristics of pavement layers. Due to the complex interferences between various layers and their time consumption, the traditional pavement analysis, and design methods were replaced with fast and powerful methods including the Finite Element Method (FEM) and the Discrete Element Method (DEM). FEM requires less computational power and is more appropriate for continuous environments. In this study, flexible pavement consisting of 5 layers (surface, binder, base, subbase, and subgrade) had been analyzed using FEM. The ABAQUS (6.14-2) software had been utilized to investigate the influence of the base layer depth on ver
... Show MoreActing on the Holy Qur’an by contemplating its meanings, stopping at its commands and prohibitions, and everything in it that guides us to truth and mercy. The Holy Qur’an includes it for various purposes in one verse, and there is no doubt that this is part of the perfection of this great book, and one of the sciences of the fundamentalists is the indication of the context, and it is a great science of high rank, and it is one of the most important things that lead to the correct understanding of the miraculous and decisive book of God Almighty, and one of the best meanings of the Qur’an It was not from the context of the verses, and from here it can be said that the indication of the context is one of the origins of deriving lega
... Show Morehe assignment model represents a mathematical model that aims at expressing an important problem facing enterprises and companies in the public and private sectors, which are characterized by ensuring their activities, in order to take the appropriate decision to get the best allocation of tasks for machines or jobs or workers on the machines that he owns in order to increase profits or reduce costs and time As this model is called multi-objective assignment because it takes into account the factors of time and cost together and hence we have two goals for the assignment problem, so it is not possible to solve by the usual methods and has been resorted to the use of multiple programming The objectives were to solve the problem of
... Show MoreThe aim of this study was extraction of jojoba oil using different solvents. A mixture of waterhexane and water-ethanol are used as solvents to extract jojoba oil in a batch extraction process and compared with a pure solvent extraction process. The effects of particle size of crushed seeds, solvent-to-water ratio and time on jojoba oil extraction were investigated. The best recovery of oil was obtained at the boiling temperature of the solvent and four hour of extraction time. When seed particle size was 0.45 mm and a pure ethanol was used (45% yield of oil extraction), whereas, it was 40% yield of oil at 25% water-hexane mixture. It was revealed that the water-ethanol and water-hexane mixtures have an effect on the oil extraction yield. T
... Show MoreThe first chapter includes introduce the research and the problem of the research that there are negligence of some educational institutions and schools management , some parents and supervisors .Also there are some educators who believes that school activities are obstacles means to learning and prevent pupils from studying and understanding the subjects. That may due to social , psychological and educational reasons
The purposes of the researches come from the reports of supervision visits which indicate a lot of difficulties faced by pupils and teachers related to education activities and its influence on in education and the necessity of indentify these difficulties and remedy them
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