Jacob's disease associated with temporomandibular joint dysfunction: a case report.

Jacob's disease is regarded a rare condition in which a joint formation is established between an enlarged mandibular coronoid process and the inner aspect of the zygomatic body. Chronic temporomandibular joint (TMJ) disk displacement has been proposed as etiological factor of coronoid process enlargement. We present a 23-year-old woman with long-standing TMJ dysfunction and restricted interincisal opening, who developed a progressive zygomatic asymmetry. The patient underwent treatment by intraoral coronoidectomy and homolateral TMJ arthroscopy in the same surgery. The histopathological diagnosis of the coronoid sample was cartilage-capped exostoses with presence of articular fibrous cartilage. Although the low prevalence of this entity, it should be considered as a possible diagnosis in patients with progressive limitation of mouth opening, although a TMJ syndrome may be present as a cause of this entity.