Biomechanics of incisor retraction with mini-implant anchorage

Mini-implants have been successfully incorporated into orthodontic practice all over the world. One of the most popular applications of mini-implant anchorage is to facilitate retraction of the anterior teeth. This article reviews the mechanics involved in anterior tooth retraction with mini-implant supported anchorage. An attempt has been made to synthesize information available in the literature and present it in a manner that is easily understandable from a clinical perspective. We discuss the fundamental differences mini-implant based incisor retraction has when compared to conventional techniques, mechanical factors affecting this process and provide a step-by-step analysis of incisor retraction. In addition, various models of space closure are discussed that have evolved through careful evaluation of in vitro and in vivo experiments.