A 7-year-old boy presented with severe facial asymmetry due to marked right facial hypoplasia. MRI confirmed mandibular ankylosis accompanied by large secondary tissue retraction and microretrognathia, allowing only a maximum interincisal opening of 4 mm, in addition to class II malocclusion.
The ankylotic block of the right temporomandibular joint was surgically resected by means of osteotomy at the level of the condylar neck and right coronoidectomy, followed by reconstruction with an interposition chondrocostal graft. At the time of final discharge, the patient maintained a mouth opening of 3 cm.

