Mandibular deformities: single-vector distraction techniques for a multivector problem

Single-vector distraction devices have been criticized for creating a malocclusion in an attempt to correct a three-dimensional mandibular deficiency, resulting in the evolution of a multiplanar device. Although there are indications for the use of a multiplanar device, a vast number of patients with mandibular hypoplasia can be effectively treated with a single-vector device, producing a normal occlusion and an aesthetic result while minimizing facial scarring and simplifying postoperative care. The purpose of this review was to describe surgical techniques whereby a single-vector device is effectively used in treating a multivector mandibular deficiency.A retrospective analysis of all patients who underwent mandibular distraction at the Children's Hospital of Philadelphia between 1996 and 2005 with a semiburied, uniplanar device was conducted. Charts, photographs, graphs, operative reports, computed tomography scans, and cephalometrograms were reviewed for those patients undergoing uniplanar mandibular distraction.Ten unilateral and 4 bilateral distractions were performed. In these 14 patients, causes included hemifacial microsomia, Treacher Collins syndrome, posttraumatic hypoplasia, and temporomandibular joint ankylosis with hypoplasia. The average device distraction was 29 mm (range, 18-34 mm). The average age at distraction was 8.4 years (range, 4-15 years). Surgical techniques for these patients will be described in detail. The single-vector, semiburied device can be effectively used to aesthetically correct a three-dimensional problem and to produce or maintain a class I occlusion while simplifying postoperative management and minimizing facial scarring.