
The orthodontic tooth movement occurs by an inflammatory process involving osteoclasts, osteoblasts, neuropeptides, cytokines and alterations in innervation and local vascularization. Bone remodelling activity can be regulated either by local factors, such as the applied forces, or by systemic factors, such as drugs, hormones and vitamins. Following review article is to discuss the effects of drugs and systemic factors capable of affecting bone metabolism and influencing the orthodontic tooth movement during the entire treatment phase. The NSAIDS, bisphosphonates and sex hormones can reduce the tooth movement, while the corticosteroids, relaxin, thyroid hormones, parathyroid hormone and vitamin D can increase the rate of tooth movement. Thus, it is necessary to know patient’s history of medical and other conditions which he is on medication for, which might or might not affect tooth movement necessary for successful orthodontic treatment.