fa Force levels in complex tooth alignment with conventional and self-ligating brackets ارتودنسی Orthodontics پژوهشي Research <p> <strong>Introduction </strong></p><p> The force applied to the teeth is a variable of orthodontic treatment that can be controlled. Poor control of the applied force can lead to adverse biologic effects as well as undesirable tooth movements. The selected archwire-bracket combination is a primary determining factor in the force level applied to a tooth during orthodontic treatment. The aim of this research was to use an experimental biomechanical setup to measure forces generated during complex orthodontic tooth movements with various archwire-bracket combinations. </p><p> <strong>Methods</strong></p><p> <strong> </strong>The materials consisted of 3 types of 0.022-in slot orthodontic brackets: (1) conventional brackets (Victory Series [3M Unitek, Monrovia, Calif] and Mini-Taurus [Rocky Mountain Orthodontics, Denver, Colo]), (2) self-ligating brackets (SmartClip [3M Unitek] and Time3 [American Orthodontics, Shegoygan, Wis]), and (3) a conventional low-friction bracket (Synergy [Rocky Mountain Orthodontics]) and 4 archwire types: (1) 0.012-in stainless steel (3M Unitek), (2) 0.0155-in coaxial (Advanced Orthodontics [Näpflein, Düsseldorf, Germany]), (3) 0.012-in Orthonol (Rocky Mountain Orthodontics), and (4) 0.012-in Thermalloy (Rocky Mountain Orthodontics). Stainless steel ligatures and elastomeric rings were used. The materials were used in different combinations in a simulated malocclusion that represented a maxillary central incisor displaced 2 mm gingivally (x-axis) and 2 mm labially (z-axis).</p><p> <strong> Results</strong></p><p>  The lowest forces were measured when the brackets were combined with either the coaxial or the Thermalloy archwires the forces ranged from 3.4 ± 0.2 to 0.7 ± 0.1 N in the x-axis direction, and from 4.5 ± 0.3 to 0.5 ± 0.1 N in the z-axis direction. The highest forces were measured in combination with stainless steel archwires the forces ranged from 6.3 ± 0.3 to 3.0 ± 0.1 N in the x-axis direction, and from 6.3 ± 0.3 to 1.7 ± 0.1 N in the z-axis direction. </p><p> <strong>Conclusions</strong> </p><p> We recommend 0.0155-in coaxial and 0.012-in Thermalloy archwires for leveling and alignment. Elastomeric rings, when used with conventional brackets, increased the force applied to the teeth. </p><hr><p></p><p> <strong>Source: </strong>American Journal of Orthodontics & Dentofacial Orthopedics </p><p> <a href="http://www.ajodo.org/article/S0889-5406(12)01233-4/abstract" target="_blank"><font color="#0000ff">Full Text</font></a></p> 0 0 http://idai.ir/browse.php?a_code=A-10-32-1770&slc_lang=fa&sid=1 Mona A. Montasser 10031947532846008346 10031947532846008346 Yes Orthodontic Department, Faculty of Dentistry, Mansoura University, Mansoura, Egypt Tarek El-Bialy 10031947532846008347 10031947532846008347 No Department of Orthodontics, School of Dentistry, University of Alberta, Edmonton, Alberta, Canada Ludger Keilig 10031947532846008348 10031947532846008348 No Department of Oral Technology, School of Dentistry, University of Bonn, Bonn, Germany Susanne Reimann 10031947532846008349 10031947532846008349 No Department of Oral Technology, School of Dentistry, University of Bonn, Bonn, Germany Andreas Jäger 10031947532846008350 10031947532846008350 No Orthodontics Department, School of Dentistry, University of Bonn, Bonn, Germany Christoph Bourauel 10031947532846008351 10031947532846008351 No Department of Oral Technology, School of Dentistry, University of Bonn, Bonn, Germany