Positional changes of the lips concomitant to incisor retraction: an important issue in orthodontics

Lip response to incisor retraction following extraction therapy is continuously investigated. The following is a summary of available evidence in this regard. The reaction of the lips to incisor retraction cannot be predicted with certainty. This is due to many variables such as gender, growth, morphology, and function. Also, for some patients, it is difficult to completely relax their lips during cephalogram taking. All these variables interact in studies on this topic.