Orthotics & Prosthesis
Mostafa Lashgari; Farzan Ghalichi; Behnam Mirzakouchaki
Volume 7, Issue 4 , June 2013, , Pages 341-349
Abstract
Orthodontic specialists interest in study of tooth movement mechanic, such as the relationship between applied force and the rate of tooth movement in orthodontic treatment. It is because of the complexity and variety of factors that can affect orthodontic treatment. The friction force at the contact ...
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Orthodontic specialists interest in study of tooth movement mechanic, such as the relationship between applied force and the rate of tooth movement in orthodontic treatment. It is because of the complexity and variety of factors that can affect orthodontic treatment. The friction force at the contact surfaces with an undetermined magnitude, makes the orthodontic treatment unpredictable. In this study, friction coefficient and forces were investigated in new designed bracket that had beveled edge which has been modeled based on standard bracket. Torque, tip and angulations angles of the brackets slot are designed. Arch wires were modeled by two rectangular and circular cross-sections and the effect of geometry on the stress distribution and the friction force was investigated using Finite Element Method (FEM). The results have showed that the stress concentration generated in the bracket which has been the most curvature, decreased compared to the standard bracket at the contact wire and bracket braces. In addition, results have showed that friction in the beveled edge bracket was significantly decline compared to the standard bracket and also are less than the type with minor curvature. Results of investigation of friction between the two types of round and square wire, have revealed that the round wire has lower friction and confirmed previous studies. Finally, due to the reduced friction in the brackets which have been the most curvature, this type of design is appropriate to decrease friction force.
Dental Biomechanics
Jalil Rezaei Pajand; Seyed Mohammad Chavoshi
Volume -1, Issue 2 , June 2005, , Pages 153-158
Abstract
The main objective of this study is to present a mathematical model for frictional forces in orthodontic tooth movements. In order to produce lighter and more efficient sliding movement, good estimation of frictional forces must be determined. For the purpose of analysis, a typical bracket with a circular ...
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The main objective of this study is to present a mathematical model for frictional forces in orthodontic tooth movements. In order to produce lighter and more efficient sliding movement, good estimation of frictional forces must be determined. For the purpose of analysis, a typical bracket with a circular cross section arch wire is considered with a view to examine the effect of ligation technique (shape), geometry and properties of ligature, and arch wire on the friction forces between ligature and arch wire. Both uniform and non-uniform distributions of contact forces are considered. The result presented herein indicated that, for circular orthodontic arch wires, friction force between ligature and wire is proportional to tensile force in elastomeric ligature. This force is depended on the shape of ligation, material properties and geometries of wire, bracket and ligature.