The orthodontic force application causes inflammatory reaction leading to changes in blood flow causing perception of orthodontic pain. This inflammatory reaction results in release of various chemical mediators eliciting a hyperalgaesic response. The presence and the elevation of several released neuropeptides demonstrates the molecular aspect of the orthodontic pain. The pathway of pain appears to be not clear although the presence of several publications about this topic, further research is required to clarify this issue. The mechanism of orthodontic tooth movement involves an inflammatory reactions in the periodontium and dental pulp, the changes in blood flow caused by the forces applied by appliances which stimulate the release of various
