Effect of Platelet rich plasma injection for accelerating orthodontic tooth movement in canine retraction cases - A Randomised Controlled Trial.

Orthodontic tooth movement is described as a process ofcontinuous remodeling of tissues surrounding the root. Thisremodelling takes place under the mechanical forces applied duringorthodontic treatment. One of the major concerns of orthodontic treatment is its longerduration. To counteract this problem, there has occurred a need toincrease the rate of tooth movement. Accelerating orthodontictooth movement has long been desired for its multiple potentialbenefits, including shorter treatment duration, reduced side effects(such as oral hygiene-related problems, root resorption, and opengingival embrasure spaces), enhanced envelope of tooth movement,differential tooth movement, and improved posttreatmentstabilityâ€. Various methods that can increase the rate of orthodontic toothmovement and reduce the treatment time, include non-surgicalmethods like low-intensity laser therapy, local injections ofprostaglandins, 1, 25(OH)2D3 (the active form of vitamin D3),osteocalcin and relaxin around the alveolar socket. othermethods as electric stimulation and resonance vibration havebeen tried. Surgical methods mainly include corticotomy -facilitatedtooth movement. Platelet-rich plasma (PRP) is an autologous component of blood witha high concentration of platelets and has shown to accelerateorthodontic tooth movement. Platelets, in turn, have α-granules which are the source for many growth factors and the amount ofwhich is higher in PRP when compared to serum. Due to thepresence of a large amount of these growth factors within the PRPthere is faster bone repair and acceleration of tooth. As such, PRPcontains not only a high level of platelets but also the fullcomplement of clotting factors and secretory proteins. The sevenknown growth factors in PRP are Platelet-derived growth factor asPDGFαα, PDGFαβ, PDGFββ, transforming growth factor-beta-TGF-β1,TGF-β2, Vascular endothelial growth factor (VEGF) and epithelialgrowth factor (EGF). Platelet-derived growth factor (PDGF) is released upon activation ofosteoblasts, results in an increase of new bone formation. PDGFinitially stimulates bone resorption and stimulates the proliferationand chemotaxis of osteoblasts. Thus, functions as an anabolic factorin bone metabolism. Vascular endothelial growth factor (VEGF), is an angiogenicmediator, is believed to play a critical role in skeletal developmentby enhancement of angiogenesis. TGF can stimulate both osteoblastic and osteoclastic activities.PRP along with growth factors also have a rich content of cytokinesthat have a major role during orthodontic tooth movementthroughout mediating differentiation, activation, and survival of allbone cells supported the idea that PRP could have a possible effecton orthodontic tooth movement. As PRP includes a patient’s own platelets, the risk of transmissiblediseases and adverse reactions is reduced making PRP a safe andefficient method of accelerating orthodontic tooth movement. To simulate the effects of surgical insult without surgery, the localinjection of cytokines or hormones could be a substitute for surgical insults, but it is not practical clinically due to its systemiceffects and the need for frequent injections. Injection of autologous platelet-rich plasma (PRP) could be a better substitute for bonesurgery.