Oromandibular dystonia as a cause of temporomandibular disorder

Résumé

Temporomandibular disorders (TMD) can have multiple etiologies, including oromandibular dystonia (OMD). However, in a few cases, the OMD can evolve from cervical dystonia (CD), leading to severe bone degeneration.

The purpose of this case report of a 64-year-old woman presenting to the Outpatient Neurology Clinic of the Federal University of Bahia is to illustrate the development of oromandibular dystonia with temporomandibular joint (TMJ) dysfunction after 10 years of cervical dystonia. Clinical examination showed bone degeneration of the mandibular ramus and right TMJ click, a prevalent sound in patients with temporomandibular disorders when they open their mouths or chew. After onabotulinum toxin type A injections in the right lateral pterygoid muscle, the patient improved in swallowing and pain.

This case highlights the importance of close follow-up of cervical dystonia patients to identify new dystonic muscles. In our patient, lateral pterygoid muscle involvement was followed by several comorbidities, such as dysphagia and jawbone abnormalities.