The evolution of mandibular distraction: Device selection

Background: Mandibular distraction has evolved from the use of external to the use of intraoral and semiburied devices. The authors highlight the evolution of the semiburied technique. The authors evaluate advantages and limitations, and report perioperative events for external and semiburied techniques to establish the indications for selection of the different devices. Methods: A retrospective review was conducted of patients undergoing mandibular distraction at the New York University Langone Medical Center from the authors' introduction of mandibular distraction in May of 1989 to June 30, 2009. Perioperative events were stratified into three groups: minor incidents, moderate incidents, and major incidents. Results: A total of 211 mandibular distraction procedures were performed: 129 external procedures on native bone, 37 external procedures on grafted bone, and 45 semiburied procedures on native bone. Minor incidents were morecommon with the semiburied device (62 percent) compared with external devices on native (26 percent) and grafted (38 percent) bone. There were fewer moderate incidents with the semiburied device (18 percent) than with the external device on native (22 percent) and grafted (30 percent) bone. In contrast to the external technique, no major incidents were seen with semiburied distraction. Conclusions: The semiburied device reduces scarring and has the mechanical advantages of being applied directly to the bone, less vulnerable to dislodgment, and more favorable for a vertical vector. However, its use requires more bone stock and it has the disadvantage of requiring a second operation for removal. Semiburied distraction is safe, reliable, and indicated for lengthening of the hypoplastic mandible where there is adequate bone stock for its attachment.