Frictional Resistance in Self-Ligating Orthodontic Brackets and Conventionally Ligated Brackets

Abstract

Objective:To compare the amount of expressed frictional resistance between orthodontic selfligating brackets and conventionally ligated brackets in vitro as reported in the literature. Methods: Several electronic databases (Medline, PubMed, Embase, Cochrane Library, and Web of Science) were searched without limits. In vitro studies that addressed friction of self-ligating brackets compared with conventionally ligated brackets were selected and reviewed. In addition, a search was performed by going through the reference lists of the selected articles to identify any paper that could have been missed by the electronic searches. Results: A total of 70 papers from the electronic database searches and 3 papers from the secondary search were initially obtained. After applying the selection criteria, only 19 papers were included in this review. A wide range of methods were applied. Conclusions: Compared with conventional brackets, self-ligating brackets produce lower friction when coupled with small round archwires in the absence of tipping and/or torque in an ideally aligned arch. Sufficient evidence was not found to claim that with large rectangular wires, in the presence of tipping and/or torque and in arches with considerable malocclusion, self-ligating brackets produce lower friction compared with conventional brackets. (Angle Orthod. 2009;79: 592-601.)

Evaluation of friction produced by self-ligating, conventional and Barbosa Versatile brackets

“…It allows for passive trapping of the wire (except in the interactive brackets with larger diameter wires) without the involvement of any outside connecting agent and allows the use of lighter forces due to reduced friction, which helps to preserve the anchorage 3,9,10,14,17,18,21 .…”

“…With the frequent use of sliding mechanics in Orthodontics, friction control has become a major concern for successful treatment [1][2][3][4] . The use of forces below values required for tooth movement prolongs treatment time.…”

Retrospective investigation of the effects and efficiency of self-ligating and conventional brackets

“…However, there was little evidence to claim an advantage with large rectangular wires. Also, it was reported that friction in both bracket types increased as the archwire size increased [Ehsani et al, 2009]. Another important factor to consider is resistance to sliding.…”

Comparative evaluation of anchorage loss between self-ligating appliance and Conventional pre-adjusted edgewise appliance using sliding mechanics – A retrospective study

“…Sufficient evidence could not be found to claim that with large rectangular wires, in the presence of tipping and/or torque and in arches with considerable malocclusion, self-ligating brackets produce lower friction compared with conventional brackets. 17 For many years arguments has raged over whether the fluid media is a lubricant or an adhesive when a bracket is slid through an archwire. In vitro studies have demonstrated friction to be more in dry state as compared to wet states.…”