Submerged intraoral device for mandibular lengthening.

The authors report a new technique for mandibular distraction. Lengthening of the mandible by gradual intraoral distraction was obtained in nine young patients. An intraoral device was used in order to avoid external scars. Seven patients had hemifacial microsomia, one patient had a ramus hypoplasia after TMJ ankylosis and one patient had the Treacher-Collins syndrome. The amount of mandibular lengthening ranged from 12 to 28 mm depending on the duration of expansion. Retention after expansion, to allow ossification to take place, lasted for 3 weeks on average. The follow-up period ranged from a minimum of 5 months to a maximum of 44 months.