Oromandibular dystonia screening questionnaire for differential diagnosis

Objectives Oromandibular dystonia, which is characterized by stereotypic, task-specific, or sustained contractions of masticatory and/or lingual muscles, is frequently misdiagnosed as temporomandibular disorders or psychogenic disease. Diagnostic delay in oromandibular dystonia is not acceptable; thus, a screening tool that can distinguish this condition from a temporomandibular disorder may be helpful for medical professionals unfamiliar with involuntary movements or temporomandibular disorders. Materials and methods A questionnaire that included questions on the clinical features of oromandibular dystonia, such as stereotypy, task-specificity, sensory tricks, and morning benefit, and included questions to rule out temporomandibular disorders (total point range 0–40) was administered to 553 patients suspected to have involuntary movements. Results Based on a careful examination and the differential diagnosis, the patients were divided into four groups: oromandibular dystonia ( n = 385), oral dyskinesia ( n = 84), psychogenic (functional) movement disorder ( n = 50), and temporomandibular disorders ( n = 34). The questionnaire had a high level of internal consistency as measured by the Cronbach’s α (0.91), and item-total correlation was significant ( p