Sequential treatment of unilateral temporo-mandibular joint ankylosis with distraction osteogenesis - a case report.

Temporo-mandibular joint (TMJ) ankylosis is a common cause of acquired mandibular deformity in children and adults. It causes reduced mouth opening and limitation of functional movements resulting in mandibular growth impairment leading to mandibular retrognathism and facial asymmetry. The treatment of TMJ ankylosis is challenging, not only due to the complexities involved and the risk of relapse but also because it requires a high degree of patient cooperation. The treatment may be performed in 1 or 2 phases consisting of the initial release of ankylosis with or without condylar reconstruction, followed by a correction of mandibular hypoplasia and of facial asymmetry by orthognathic surgery. Distraction osteogenesis has been proposed to treat cases with severe deformity due to its inherent advantages of generating new bone and soft tissue. This case report describes the staged treatment of a patient with unilateral TMJ ankylosis. The patient presented with significant facial deformity due to mandibular retrognathism and facial asymmetry as a consequence of impaired growth. The treatment objectives included releasing ankylosis to establish mouth opening, addressing the dentofacial deformity and achieving a normal occlusion. The patient was treated with a combined surgical-orthodontic approach including distraction osteogenesis. The case was treated with a rigid external distractor and CBCT generated facial models were used to plan and execute adjunctive surgeries. The staged treatment approach resulted in a significant improvement of facial aesthetics.