Temporomandibular joint reconstruction in children using costochondral grafts

Purpose: The aim of this study was to evaluate the postoperative growth of the mandible after reconstruction of the condylar process using costochondral grafts in children. Patients and Methods: Temporomandibular joint (TMJ) ankylosis was surgically treated and the joint reconstructed with a costochondral graft (CCG) in two boys and eight girls with a mean age of 7.4 years. Two children had bilateral ankylosis. Postoperative changes and craniofacial growth were monitored by lateral and posteroanterior (PA) cephalograms annually from 2 to 6 years (mean of 4 years). Results: Postoperatively, in the eight children with unilateral TMJ reconstruction, the mandible (Co-Gn) grew an average of 14.7 mm in length on the affected side and 15.1 mm on the nonaffected side; ramus length (Co-Go) increased an average of 7.1 mm on the affected side and 7.3 mm on the nonaffected side. However, in five of the children the chin progressively deviated toward the nonaffected side after TMJ reconstruction. The CCGs tended to have a more vertically directed condylar growth pattern and a more laterally positioned condyle. In the two cases with bilateral TMJ reconstruction, the CCGs grew until there was a mandibular prognathism that required orthognathic surgery to set back the mandible. Conclusions: Using CCGs to reconstruct TMJ ankylosis in children provides a functional condyle with growth potential. However, there is a possibility of excessive growth of the graft, resulting in deviation of the chin and mandibular prognathism years later.