Xerostomia and Salivary Gland Dysfunction

Why Saliva Matters

A healthy adult produces about a liter of saliva per day. Beyond simple lubrication, saliva:

• Protects against decay by neutralizing acids and remineralizing enamel
• Controls bacterial growth through antimicrobial proteins
• Supports digestion with enzymes that begin breaking down food
• Enables taste by dissolving food chemicals and carrying them to taste receptors
• Assists swallowing by lubricating food into a bolus
• Maintains oral tissue health by keeping mucosa moist and protected
• Cleanses the mouth by clearing food debris and bacteria

When salivary function is significantly reduced, all of these functions suffer.

Causes in Cancer Survivors

Head and neck radiation. The most common cause. Radiation damages salivary gland tissue, often permanently. Modern intensity-modulated radiation therapy (IMRT) can sometimes spare parotid function partially, but most patients with significant head and neck radiation experience some lasting reduction in saliva.

Chemotherapy. Some chemotherapy regimens cause dry mouth, often less severe than radiation but still significant.

Bone marrow and stem cell transplant. Total body irradiation, conditioning chemotherapy, and chronic graft-versus-host disease can all reduce saliva.

Medications. Many medications cause dry mouth as a side effect, opioids, antidepressants, anticholinergics, and others. Survivors taking multiple medications may have compounding effects.

Sjögren syndrome. Some cancers and treatments are associated with autoimmune conditions affecting salivary glands.

Symptoms

Dry mouth presents in several ways:

• Persistent thirst, particularly at night
• Difficulty eating dry foods: bread, crackers, meat
• Difficulty speaking for extended periods
• Altered taste
• Burning, stinging, or sore mouth
• Cracked lips and angular cheilitis (cracks at the corners of the mouth)
• Increased dental decay, often starting at the gumline
• Recurrent oral infections including fungal infections (oral thrush)
• Difficulty wearing dentures: they no longer adhere well or feel comfortable
• Bad breath
• Sleep disturbance from waking thirsty

Why It Matters Dentally

The dental consequences of long-term xerostomia are serious:

• Accelerated decay, sometimes called “radiation caries” when associated with head and neck radiation. Decay can wrap around teeth at the gumline and cause them to break off near the bone.
• Gum disease progression in some patients
• Oral infection susceptibility, particularly thrush
• Compromised denture wear and prosthetic fit
• Higher risk of complications from any dental procedure

Xerostomia is the underlying driver of much of the dental damage we see in survivors. Managing it actively is one of the most important things a survivor can do for long-term oral health.

Treatment and Management

There is no cure for radiation-induced gland damage. Management aims to reduce symptoms, protect teeth, and improve quality of life.

Stimulation of remaining gland function. When some gland tissue remains:

• Pilocarpine (Salagen), prescription medication that stimulates saliva production. Effective for many patients but has side effects (sweating, GI symptoms) that limit use.
• Cevimeline (Evoxac), similar mechanism, sometimes better tolerated.
• Sialogogues, gum, lozenges, or hard candies that stimulate any remaining function. Sugar-free options like Xylitol-sweetened products are preferred.

Saliva replacement. When stimulation is not enough:

• Over-the-counter saliva substitutes (gels, sprays, rinses)
• Frequent sips of water
• Specialized products like XyliMelts (slow-dissolving discs)
• Mouth-moisturizing oral rinses

Aggressive caries prevention. Custom-fit fluoride trays used at home daily, prescription-strength fluoride toothpaste, frequent in-office fluoride varnish, dietary counseling to avoid frequent sugar exposure.

Frequent maintenance. Cleanings and exams every 3 to 4 months for high-risk survivors, with attention to early decay and gum issues.

Tissue protection. Lip balms, humidifiers at night, avoidance of irritants (alcohol-containing mouthwashes, tobacco).

Treatment of secondary issues. Promptly addressing oral thrush, angular cheilitis, or any other secondary problems.

What We Provide

For survivors with xerostomia, we offer:

• Comprehensive evaluation including review of cancer history and current medications
• Custom fluoride tray fabrication
• Prescription saliva stimulant management
• Restoration of damaged teeth, see treatment for damaged teeth
• Frequent maintenance scheduling
• Management of secondary infections and tissue issues
• Coordination with oncology when needed