Abstract
The aim of this paper is to present scientific evidence for treatment mechanics with the pre-adjusted edgewise appliance. We have summarized findings from randomized and controlled clinical trials following a search of Medline and the Cochrane Clinical Trials Register (CCTR) 1970 - June 2005. Evidence was available to support our choice of archwires, use of canine lacebacks and method of space closure, thus providing the beginning of a scientific basis for our day-to-day management of fixed appliance mechanics.