Pseudoankylosis of the temporomandibular joint caused by zygomatic malformation.

Temporomandibular joint (TMJ) pseudoankylosis is characterized by limited mouth opening and mandibular movements, resulting from factors outside the joint. The authors present a case of TMJ pseudoankylosis caused by congenital zygomatic malformation and hyperplasia of the coronoid process. Treatment with coronoidectomy and postoperative physiotherapy achieved favorable results.