Article by Dr Manasa S, B.A.M.S
Oromandibular Dystonia (OMD) is a rare neurological disorder that causes involuntary and repetitive muscle contractions in the face, jaw, and mouth. These muscle spasms can result in abnormal movements or postures, making it difficult to speak, chew, or even open and close the mouth properly. OMD can develop on its own or as a result of other conditions, medications, or injuries, especially those affecting the nervous system or the mouth area. It may also be linked to factors like dental procedures, trauma, or genetic predisposition.
Other names
– Orofaciomandibular dystonia
– Orofacial buccal dystonia
– Lingual dystonia
– Jaw dystonia
– Cranial dystonia
– Adult-onset facial dystonia
Classification of OMD
– Jaw opening
– Jaw deviating
– Lingual dystonia
– Combination of these
Miege’s Syndrome – The combination of OMD, blepharospasm, and dystonic movements of the upper face is called as Miege’s syndrome.
Prevalence
Oromandibular dystonia (OMD) is a rare neurological disorder that affects the muscles of the jaw, mouth, and face, causing involuntary contractions and abnormal movements. It has a reported prevalence of approximately 6.9 cases per 100,000 people, with an incidence of up to 3.3 cases per million. OMD often leads to difficulty in speaking, chewing, or swallowing, severely impacting the quality of life.
Causes of Oromandibular Dystonia (OMD)
- Neurological disorder – OMD may occur independently, with or without hereditary factors.
- Drug-induced – Neuroleptic drugs and certain medications can trigger OMD.
- Trauma – Central nervous system trauma, hypoxic brain damage, and peripheral injuries.
- Metabolic disorders – Conditions such as Wilson’s disease.
- Brain lesions – Ischemic or demyelinating lesions in the upper brain stem.
- Peripheral trauma – Injury to the face or mouth, including dental procedures.
- Hormonal factors – Possible links between hormonal changes and OMD development.
- Genetic predisposition – Carriers of idiopathic torsion dystonia (ITD) gene.
- Ill-fitting dental appliances – Poorly fitted dentures or dental work can trigger or worsen OMD.
- Associated movement disorders – Pre-existing conditions like Parkinson’s disease may contribute to OMD.
Clinical Manifestations of Oromandibular Dystonia (OMD)
Onset
Typically occurs between ages 40 to 70 and is more common in women.
Symptom Triggers
Symptoms occur during activities such as speaking, chewing, and even praying; stress often triggers them.
Common Symptoms
– Difficulty speaking (dysphonia)
– Difficulty chewing or swallowing (dysphagia)
– Jaw movements such as unconscious opening/closing or twisting
– Social embarrassment, reduced quality of life, depression, and weight loss
Progression
– More severe in post-traumatic OMD than primary OMD.
– Post-traumatic OMD rarely spreads to other muscle segments.
– Sensory Tricks: Specific sensory stimuli may temporarily relieve dystonia, unlike in other types of dystonia like cervical dystonia.
– Laboratory Tests: Usually normal.
Dental and Facial Signs and Symptoms of OMD
Affected Functions: Impaired chewing, speech alterations, jaw opening / closing, and temporomandibular disorders (TMD).
Dystonic Spasms:
– Nasal contractions, facial grimacing, lip pursing, bruxism, and tongue dyskinesia.
– Involuntary jaw closure or jaw-opening dystonia can lead to TMJ overload.
Other Symptoms
– Rare breathing difficulties and dysarthria (speech problems).
– Bruxism induced by OMD stops during sleep.
– Potential Oral Damage: Jaw trauma, dental wear, fractures, and trauma to lips, gums, and tongue.
Pain
Muscle tension or tiredness is common, but pain is rarely reported. Around 20% of edentulous patients report pain, often linked to oral structures rather than muscles.
Oral Health Issues
Tooth loss and dry mouth (hyposalivation) are common due to dystonic activities.
Diagnosis of OMD (Oromandibular Dystonia)
Diagnosis is clinical and complex.
Varies in forms and severity.
No specific diagnostic test.
Usually diagnosed by neurologists based on:
– Patient information
– Medical history
– Neurological examination
– Confirmation through intramuscular EMG.
Differential diagnosis includes:
– TMJ disorders (e.g., bruxism, spontaneous condylar dislocation)
– Hemifacial spasm
– Psychological disorders.
Symptoms may worsen with emotional factors, causing delayed diagnosis.
Treatment of OMD (Oromandibular Dystonia)
Medication
– Efficacy not well-established.
– Commonly used drugs: anticholinergics, baclofen, benzodiazepines, antiparkinson drugs, anticonvulsants, carbamazepine, dopamine receptor antagonists, levodopa, and lithium.
Physiotherapy
– Promotes brain re-wiring to reduce dystonic movements.
– Effective in some patients, especially musicians.
Botulinum Neurotoxin (BoNT) Injections
– Blocks acetylcholine release, causing temporary muscle paralysis.
– Effective but technique-dependent.
– Side effects: jaw weakness, tremor, dysphagia, loss of smile.
– Can become non-responsive after multiple injections.
Muscle Afferent Block (MAB)
– Effective for OMD but not for dyskinesia.
– Low-cost with no major side effects.
Operative Therapies
– No specific surgical treatments for OMD.
– Coronoidotomy may help in severe jaw-closing dystonia when other treatments fail.
Other Therapies
– Psychosocial therapy, occupational therapy, and support groups.
– Cognitive behavioral therapy.
– Deep brain stimulation, pallidotomy, thalamotomy, focused ultrasound lesioning.
– Acupuncture reported to help in some cases.
In conclusion, Oromandibular Dystonia (OMD) is a complex movement disorder that affects the muscles of the face, jaw, and mouth, causing discomfort and difficulty with daily functions like speaking and eating. Although the exact causes of OMD are not fully understood, factors such as neurological conditions, trauma, medications, and dental procedures can contribute to its development. Early diagnosis and appropriate treatment, such as medication, botulinum toxin injections, or supportive dental care, can help manage symptoms and improve quality of life for those affected.
A study reflects that the surface EMG can be used to effectively evaluate treatment outcomes in patients with OMD. It could be considered as an adjunctive diagnostic tool in managing patients with dystonia.
Another study tells that OMD is a chronic and disabling focal dystonia and the study conducted by them showed prevalence of female patients, an onset in middle age and predominantly idiopathic aetiology. Jaw opening was found to be the most frequent clinical type of OMD, unlike in other studies.
Beneficial Yoga Poses for OMD
– Balasana – Child’s Pose
– Utthita Trikonasana – Extended Triangle Pose
Other useful poses for Dystonia may also help, like –
– Viparita Karani – Legs up the wall
– Dandayamana Bhramanasana / Parsva Balasana – Bird Dog Pose
Ayurveda Understanding of Oromandibular Dystonia (OMD)
No single condition explained in Ayurveda can be directly correlated with OMD.
Looking at the general description of the disease Oromandibular Dystonia and also its causes and signs and symptoms, the below mentioned conditions explained in Ayurveda treatises can be considered for closer correlation with this condition. They are –
– Vata Vyadhi
– Ardita
– Pakshaghata / Pakshavadha
– Ekanga Vata
– Mukhagata Mamsa-Gata Vata
– Hanugraha / Hanustambha
OMD, by its description, clearly looks like a Vata Vyadhi. Symptoms of OMD are scattered amongst the conditions listed above. Mainly this condition looks similar to the description and symptoms of Ardita and Hanugraha.
Oromandibular Dystonia shall be treated on the lines of Vata Vyadhi treatment in general and also on the linens of treatment of the above said conditions as and when needed, as per the skill and decision of the physician.
Related Reading – ‘Oromandibular Dystonia – Ayurveda Understanding’
