Understanding Involuntary Chewing Movements
Constant chewing in the elderly is a condition often referred to as 'phantom chewing' or 'geriatric chewing.' This is when an older adult makes repetitive, unintentional chewing motions, even when there is no food in their mouth. It is an involuntary action, meaning the person has no conscious control over it, and can stem from a variety of factors ranging from dental issues to more complex neurological problems.
The Spectrum of Causes
Understanding the specific cause of the chewing is crucial for proper management and care. Causes can be categorized into several key areas:
- Neurological Disorders: Conditions affecting the brain are a common and serious cause of involuntary mouth movements.
- Tardive Dyskinesia (TD): A disorder characterized by repetitive, involuntary muscle movements, often affecting the face, jaw, lips, and tongue. It is most frequently a side effect of long-term use of antipsychotic medications, which are sometimes used to treat mental health conditions in older adults. TD-related chewing can be persistent and may sometimes become permanent.
- Dementia: Patients with advanced dementia may exhibit a behavior called perseveration, which involves repeating gestures, words, or movements, including chewing. This is a symptom of cognitive decline where the brain struggles to control and stop repetitive actions.
- Edentulous Dyskinesia: A specific type of orofacial dyskinesia seen in elderly individuals who are edentulous (have no teeth). The proprioceptive loss from missing teeth is thought to play a role in this movement disorder.
- Dental and Oral Health Issues: Problems with the teeth, gums, and dentures can trigger chewing motions.
- Ill-fitting dentures: Dentures that don't fit properly can be uncomfortable, prompting the individual to constantly adjust them with chewing movements.
- Missing teeth: The loss of teeth can weaken facial and mouth muscles, leading to subconscious chewing to keep the muscles active.
- Oral pain: Conditions like periodontal disease or other oral pain can cause a person to chew or rub their gums.
- Medication Side Effects: Beyond antipsychotics, other medications can cause dyskinesia or related movements.
- Antidepressants: Certain SSRIs and mood stabilizers have been linked to inducing orofacial dyskinesia.
- Other Medications: Some anti-seizure drugs and other pharmaceutical agents may also list involuntary movements as a potential side effect.
- Other Factors:
- Dry mouth (Xerostomia): A common side effect of many medications and a natural result of aging, dry mouth can lead to chewing movements as the person tries to stimulate saliva production.
- Muscle weakness: A general decline in muscle strength can contribute to difficulty controlling facial muscles.
Signs, Symptoms, and Diagnosis
Recognizing constant chewing is the first step, but a proper medical diagnosis is essential to determine the underlying cause. Key indicators and diagnostic steps include:
- Observation of movements: Noticing repetitive lip-smacking, tongue-rolling, or jaw clenching, especially when not eating.
- Comprehensive medical history: Reviewing current medications and any history of neurological or psychiatric conditions.
- Dental evaluation: A dentist can check for ill-fitting dentures, infections, or other oral issues.
- Neurological examination: A neurologist can evaluate for signs of tardive dyskinesia or other movement disorders.
- Cognitive assessment: For dementia patients, a neuropsychological evaluation can help understand the nature of the repetitive behaviors.
Managing and Treating Constant Chewing
Management strategies depend on the root cause and can involve a combination of medical, dental, and supportive interventions. A multi-disciplinary approach is often most effective.
Medical and Pharmaceutical Management
- Medication Review: If a medication is the cause, a doctor may adjust the dosage, switch to an alternative, or gradually discontinue the drug. It's important never to stop medication without a doctor's guidance.
- Treating Underlying Conditions: Managing the core condition, such as dementia or depression, may help alleviate the symptoms.
- Treating Dry Mouth: For xerostomia, a doctor can recommend specific mouth rinses, saliva substitutes, or other treatments.
Dental Interventions
- Denture Adjustment or Replacement: A dentist can ensure dentures fit securely and comfortably, eliminating a common irritant that leads to chewing motions.
- Oral Health Care: Regular dental check-ups and addressing any infections or pain can resolve chewing that stems from oral discomfort.
- Mouth Guards: In cases of bruxism (teeth grinding), a dentist may recommend a custom-fit mouth guard to protect the teeth.
Behavioral and Supportive Strategies
- Caregiver Patience: It is crucial for caregivers to understand that the behavior is involuntary. Patience and empathy are vital to avoid causing the person stress.
- Consistent Reminders: For individuals with dementia, gentle, calm reminders to close their mouth can be effective for short periods.
- Provide Chewable Items: Offering safe, soft, chewable objects can provide a sensory outlet for the behavior. As with any item, ensure it is not a choking hazard.
- Distraction and Engagement: Engaging the person in conversation or a different activity can sometimes interrupt the chewing motion. Creating a calm, low-stress environment can also be helpful.
Comparison of Potential Causes
| Feature | Tardive Dyskinesia | Dementia | Dental Issues / Dry Mouth |
|---|---|---|---|
| Underlying Cause | Long-term use of certain medications (e.g., antipsychotics). | Cognitive decline leading to repetitive behaviors (perseveration). | Ill-fitting dentures, missing teeth, oral pain, or reduced saliva flow. |
| Movement Characteristics | Repetitive, involuntary movements of the mouth, tongue, and face. | Repetitive chewing gesture, can be accompanied by an open mouth due to forgetfulness. | Chewing or gumming motions to alleviate discomfort or stimulate saliva. |
| Control | Involuntary; the person has no conscious control over the movements. | Involuntary, but can sometimes be interrupted with a gentle reminder. | Unconscious effort to manage physical discomfort. |
| Associated Symptoms | May include other jerky movements of limbs or trunk. | Memory loss, confusion, and other cognitive impairments. | Oral pain, difficulty eating, or altered taste. |
Conclusion
While observing constant chewing in an older adult can be unsettling, it is a symptom with a range of possible causes, from the relatively simple to the neurologically complex. It is never a behavior that is intentionally controlled by the individual. A thorough medical and dental assessment is the most important step to determine the specific cause and develop an appropriate management plan. Early identification and compassionate care can significantly improve the individual's comfort and quality of life. For more detailed medical information on neurological movement disorders, consider visiting the National Institute of Neurological Disorders and Stroke (NINDS) at https://www.ninds.nih.gov/.
