A Case of Epidermoid Cyst Initially Misdiagnosed as Temporomandibular Joint Disorder

  • Choi, Yun-Jeong (Department of Oral Medicine, School of Dentistry, Kyungpook National University) ;
  • An, Seo-young (Department of Oral and Maxillofacial Radiology, School of Dentistry, Kyungpook National University) ;
  • Byun, Jin-Seok (Department of Oral Medicine, School of Dentistry, Kyungpook National University) ;
  • Jung, Jae-Kwang (Department of Oral Medicine, School of Dentistry, Kyungpook National University) ;
  • Choi, Jae-Kap (Department of Oral Medicine, School of Dentistry, Kyungpook National University)
  • 투고 : 2018.06.07
  • 심사 : 2018.06.20
  • 발행 : 2018.06.30


Epidermoid cyst in bony wall of external auditory canal (EAC) is a very rare pathologic condition. In addition to its extreme rarity, its positional proximity to temporomandibular joint (TMJ) might lead to clinical misdiagnosis as TMJ disorders, especially when it is accompanied by temporomandibular disorders-like symptoms. In this article, we report a patient with epidermoid cyst in anterior bony wall of EAC, which was misdiagnosed as TMJ disorder because the left TMJ pain aggravated during mastication.


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