Distraction Osteogenesis(DO), also called callus distraction, callotasis, Osteodistraction, and distraction histogenesis is a biological process of regenerating neo formed bone and adjacent soft tissue by gradual and controlled traction of the surgically separated bone segments. The application of distraction osteogenesis offers novel solutions for surgical-orthodontic management of development anomalies and defects of the craniofacial skeleton. Osteodistraction provides a means whereby bone may be modeled into different shapes to more adequately addresse the nature of skeletal deformities and asymmetries.similar to distraction osteogenesis in the long bones,craniofacial Osteodistraction evolved from skeletal traction, Osteotomy techniques and external fixation methods.