What Dental Professionals Need to Know about Parkinson’s Disease

A movement disorder, PD predominately affects the dopamine-producing neurons in the substantia nigra area of the brain.³ While the exact cause is not yet known, researchers believe that it is caused by a combination of genetic and environmental factors. The disease-which is not fatal but can be associated with serious complications-has no cure.

PD most visibly manifests itself as movement symptoms including tremor, mainly at rest; slowness and reduced movement (bradykinesia and hypokinesia); limb stiffness; and gait and balance problems (postural instability).³

But symptoms of PD vary widely from person to person and can include a host of non-movement symptoms. These include loss of smell; constipation; mental health problems like anxiety, apathy, and depression; changes in cognition and memory; and dementia. Of note to dental care providers, people with PD may have decreased saliva production or increased salivary flow.

Treatment options for PD may include medications, lifestyle adjustments, and surgery.

Independent studies across six different countries have found that people with PD have a higher rate of periodontal disease than control populations, suggesting that people with the disease are in need of oral health intervention.⁴

PD-related rigidity, tremor, and dyskinesia can make brushing and flossing teeth difficult, and the symptoms can also cause cracked teeth, tooth wear, and tooth grinding. Depression and/or dementia can also reduce a person's willingness to do these tasks.⁴

Dysphagia (swallowing issues) are common among people living with PD, along with drooling and sialorrhea (the overproduction of saliva). Bradykinesia, poor muscle control of the tongue, and upper esophageal dysfunction in PD can cause impaired saliva clearance.⁴

On the other end of the spectrum, xerostomia-dry mouth due to decreased saliva production-can also be an issue, resulting in unpleasant breath, taste changes, speech difficulty, oral bacterial growth, candidiasis (a type of fungal infection), gingival dehydration, and/or impaired swallowing. Dental hygienists may recognize xerostomia by observing loss of tongue papillae and altered gingiva, as well as a cracked, fissured, or pebbly tongue or lips.

Certain medications, like clozapine for PD-related psychosis, can reduce white blood cell count. This increases the risk for bacteria-causing dental diseases to spread elsewhere, including potentially infecting DBS electrodes.⁵ This underscores the importance of ensuring that patients with PD do not have cavities, loose teeth, or inflamed gums.

Other dental conditions people with PD may present with include:

• Dysgeusia, a bad taste in the mouth followed by a severe burning of the tongue.

• Burning mouth syndrome, a complication of candidiasis.

• Perioral dermatitis, a rash around the mouth caused by excess drooling.

• Caries, which can lead to acidification, tooth mineralization, and erosion.

• Periodontal diseases, which can destroy the structure supporting the teeth.

Mobility issues may make commuting to dental appointments difficult, and symptoms such as fatigue, anxiety, and tremor may make sitting still in the dentist's chair or opening the mouth wide challenging. Therefore, it is important to encourage patients with PD to schedule their appointments for times that work best for them and to recognize that patients with PD may require more frequent breaks during treatment. If possible, develop a relationship with your patient's care partner and reinforce the importance of maintaining good oral hygiene with the care partner.

For patients experiencing xerostomia, hygienists should advise:⁴

• Taking frequent sips of water.

• Eating moist foods.

• Using lip balm and/or artificial saliva.

• Choosing sugar-free gum.

• Using xylitol-containing lozenges that add moisture to the mouth.

• Choosing an alcohol-free mouthwash.

• Speaking to their doctor about prescribing modifications to stimulate salivation.

Additionally, to help identify oral health challenges in patients with PD, hygienists may ask a few key questions:⁴

• Do your gums bleed while brushing or overnight?

• Are any of your teeth loose?

• Can you chew all the food you want to eat?

• Do you have pain, swelling, or blisters in your mouth?

One of the most important tools we have in dealing with PD today is building awareness of the disease and the challenges those living with it face. Dental professionals who bring that awareness into their practice and are armed with some basic information about PD are in the best position to mitigate related oral health issues and help improve the quality of life for their patients living with the disease.

The Parkinson's Foundation offers a free, asynchronous online accredited course, "The Expert Care Experience: Role of Oral Health Professionals in Caring for People with Parkinson's." Visit Education.Parkinson.org to register.

Randolph Todd, DMD, is a diplomate of the American Board of Endodontics and a Parkinson's Foundation Aware in Care Ambassador.