Controlled multiplanar distraction of the mandible: device development and clinical application

Distraction osteogenesis has been shown to be an effective method of lengthening and augmenting endochondral bone. It has also been applied effectively in the reconstruction of the membranous bones of the craniofacial skeleton. With the accumulation of clinical experience in mandibular distraction, the differences between endochondral and membranous bone distraction have become apparent, especially in the limitations of uniplanar distraction for the three-dimensional reconstruction of the deficient mandible. Distraction of the mandible in a single plane cannot satisfy fully the functional and structural requirements of the patient with malocclusion as well as deficiency of the skeletal and soft tissue. This study reports the development and clinical use of a multiplanar mandibular distraction device with the ability to achieve linear distraction (Z-plane or sagittal), angular distraction (Y-plane or vertical), and transverse distraction (X-plane or coronal). The device contains two independent gear arrangements attached to two arms that extend from the central unit. Therefore, the trajectory of the regenerated bone may be changed during the distraction process. The device also allows manipulation of the various planes of movement independent of each other. Furthermore, the rotational points for the multiplanar distraction devices are located at a single point; therefore only a single osteotomy and two pin sites are required. The multiplanar distraction device allows the surgeon to customize and contour the dimensions of the distraction process by controlling the trajectory of the translation of the regenerated bone.