Mandibular distraction in temporomandibular joint ankylosis

Condylar damage during childhood can produce ankylosis and alteration of th e mandibular growth. In case of unilateral ankylosis occurring in early chi ldhood, a mandibular hypoplasia of the affected side may develop. The patie nts have limitation of mouth opening, facial asymmetry, and chin deviation toward the affected side. The aims of this study are to show the use of dis traction osteogenesis in mandibular hypoplasia associated with ankylosis an d to present our experience with a new therapeutic option for the treatment of mandibular hypoplasia with unilateral ankylosis in the childhood consis ting of the association of arthroplasty to treat the ankylosis and mandibul ar distraction to correct the facial asymmetry, both accomplished in the sa me surgical procedure. From November of 1996 to November of 1997, three male patients aged 2, 7, a nd 13 years with mandibular hypoplasia and ankylosis were treated by distra ction osteogenesis. An arthro plasty consisting of the resection of the ank ylotic block and interposition of a temporalis muscle flap, plus coronoidec tomy was done in two of them and mandibular distraction was done in all thr ee patients. Articular functional rehabilitation began on the first postope rative day. Mandibular distraction began on the fifth postoperative day wit h a rate of 1 mm per day, ending when the facial symmetry was achieved. From the first postoperative day, an increase in the mouth opening was achi eved; this increase continued until ending the distraction. The average dur ation of distraction was 22 days. Average duration of consolidation was 6 w eeks. Oral opening increased from 10 mm to 35 mm in the 7-year-old patient, from 9 mm to 27 mm in the 2-year-old patient, and from 14 mm to 38 mm in t he 13-year-old patient. To date, oral opening and facial symmetry persist. Osseous mandibular distraction together with arthroplasty offers an excelle nt new alternative for treatment of patients with mandibular hypoplasia and associated ankylosis, with minimal morbidity and complications.