Why, Dry?

Find out the difference between xerostomia or hyposalivary function.

by Shirley Gutkowski, RDH, BSDH, FACE

Dry mouth is a term that seems to have caught on. It's descriptive. The term xerostomia is equally descriptive and to top it off it's Latin, making it more of a medical term. These terms are interchangeable, and refer to a condition where a person has a sensation of mouth dryness. The condition or sensation is caused by a number of things, most notably medications.

Hyposalivation is an objective term based on measurement of saliva production, and often the composition of the saliva is altered as well. Hyposalivary function is different from xerostomia, which is a subjective feeling of having a dry mouth. You can have one without the other. Since they're the same but different, we have to make a diagnosis to formulate a treatment plan that will address the real concerns for either case.

Saliva is produced by the major and minor (accessory) salivary glands. The majority of unstimulated saliva is produced by the submandibular glands. The parotid glands produce little unstimulated saliva and kick into gear, providing saliva when stimulated by sight, smell, or chewing. The minor salivary glands spend their time in the production of unstimulated saliva, supplementing the production from the submandibular glands. Hyposalivary function is when something gets in the way of these saliva-producing glands doing their job.

Xerostomia is probably the easiest to deal with of the two. Let's study the case of 25-year-old Yehor Young, who comes to his appointment and has just started taking an allergy medication. He notices his dryness and tells Heidi Hygienist that his mouth is dry and he has been sucking on a button to keep his mouth moist. Heidi realizes she's dealing with xerostomia.

For xerostomia, simply sucking on a button may be good medicine. Anything in the mouth will stimulate salivary flow if there's any saliva to make. The presence of saliva is important for many reasons, not just kissing. Chemicals in healthy saliva release the subtle flavors in food and make mastication possible if not easier. While flavor enhancement and mastication seem like reason enoughs to treat the situation, saliva also provides the nutrients for enamel repair on a chemical level. It also makes speech physically possible and socially acceptable.

Let's look at Elsie Elder, a 73-year-old woman taking verapamil for a heart arrhythmia. She comes to the office for her annual exam, and Heidi Hygienist notices the mirror is difficult to remove from the buccal mucosa. She asks Elsie if she has noticed her mouth being dry. Elsie reports being unaware of the condition. Your differential diagnosis is hyposalivary function. It's very important to note that dry mouth, hyposalivary function, or xerostomia are not a symptoms of aging. They're not normal. Xerostomia and hyposalivary function come from a disease state or a medication.

So don't just let it go; find out what the problem is.

Sleep is often a neglected health benefit of saliva. Waking in the night to rehydrate oral tissues interrupts sleep and must be handled in a specific way — without turning on lights or having to get out of bed. Unfortunately, waking to rehydrate oral tissues is often accompanied by a trip to the restroom, which requires, at the very least, movement. More often it requires movement, exertion, and light. Recent focus on the benefits of sleep — a full night's sleep without interruption — have shown that those who sleep well are better able to handle the stresses of work and life. Good sleepers are more apt to exercise, are more cognitive and (we already know) have a reduced crabbiness factor.

Xerostomia is an easier issue to deal with because patients report problems and will likely want to comply with a therapy. A button is fine, but not for all cases. Saliva replacement with drugs like pilocarpine (Salagen 5-10 mg three times a day) and cevimeline (Evoxac 30 mg three times a day) increase salivary production. The effects usually last from two to four hours. Common reactions to these medications include sweating and diarrhea. For most cases of xerostomia, these medications are overkill and contribute to polypharmacy issues.

If Kevin Chemo arrives for his appointment and says his mouth is so dry that he has to peel his tongue from the roof of his mouth many times a night (since the radiation therapy for the mass at the base of his tongue three months ago), this is a severe case of hyposalivary function. And that brings along a host of issues that need attention, some palliative and some therapeutic.

Physicians often prescribe medications for people with serious medical issues that contribute to hyposalivary function, such as Kevin. It seems dentists don't want to prescribe long-term medications. This may be because of the complex nature of prescribing into a regimen that a patient is already on. Dental professionals should encourage patients to get all of their medications at a single pharmacy and to have a consultation with the pharmacist any time a new medication is prescribed. Putting a daily aspirin into a mix of three other medications can create serious problems. Herbs, of course, should also be included in the pharmaceutical consult.

Sustained released discs provide a fresh feeling and stimulate saliva for long periods. Not only does their oral presence stimulate saliva, the active ingredient, usually an essential oil embedded into the disc, brings it up a notch. If you use an essential oil mouthwash in practice as a pre-procedural rinse, you'll notice an increased volume of expectorant after the 30 seconds. You'll know that the intense flavor of mouthwash stimulates the protective feature of salivary flow.

The discs are made of ethyl cellulose polymer (ECP), an ingredient used to coat drug tablets. The discs are easily digested without fanfare, and ECP is hygroscopic (a word you'll be hearing more in the near future). Hygroscopic material attracts water, so even if there is only a tiny amount of moisture, the nature of the ECP will make the mucosa feel more comfortable. The ECP is impregnated with essential oils in low concentrations that are not harmful to the mucosa or hard tissues in the mouth.

Essential oils have been studied for centuries. Their use in medicine and dentistry is long established. The dosage is unique — sustained release of a very low concentration of active ingredients over a long period of time.

For simple xerostomia or breath freshening, Dentiva contains essential oils that stimulate salivary flow. Salese, with a different combination of oils and a hygroscopic cellulose, is for more severe cases. Both products are produced by Nuvora.

A similar application is called XyliMelt. Using similar principles of sustained release with a cellulose base, XyliMelt provides the oral cavity with a small amount of xylitol over a period of 60 to 120 minutes, depending on the level of salivary flow.

The Nuvora or XyliMelt products are not indicated for overnight use, even though the temptation is there. Anecdotal evidence exists of patients who do wear the discs overnight, and they offer favorable reports about their restful sleep, as well as the fresh feeling in the mouth upon awakening.

There are a number of other products that stimulate salivary flow. Sugarless gums (Orbit or Trident, for example) and xylitol candies (Spry) may work too. Study the list of ingredients and know how the active ingredient in a product works.

A diagnosis must be made before treatment begins. Dentistry is playing on the same field as medicine. The focus must be on better diagnostics, then proper treatment. How embarrassing for the team if they treat xerostomia when the patient actually has Sjögren's or a tumor.

People with hyposalivary function may have symptoms outside of the oral cavity as well. Everything may look normal upon the initial inspection, even though they may appear to have more biofilm, which is understandable. Without saliva, the biofilm can grow unchecked. The dental mirror or a gloved finger may stick to the mucosa.

The texture of the saliva may be different — white, frothy, stringy, or sticky. Other observations include:

• Frequent recurrences of oral candidiasis
• Atrophic glossitis or hairy tongue
• Enamel lesions at the gingival margin or incisal edges of anterior teeth
• Increased rate of enamel lesion development
• Chronic oral pain or burning sensation
• Patient awareness of normal intraoral structures
• Frequent cheek biting
• Sensation of swollen cheeks or salivary gland swelling
• A sensation of a film, grit, or sand on teeth or in mouth
• A sense of a bad taste or bad breath
• Frequent thirst
• Difficulty with speech
• The complaint of thick saliva

  Non-oral symptoms can be:

  • Frequent dry cough
  • Difficulty swallowing
  • Blurred vision or the sensation of burning, itching, gritty eyes that require eye drops
  • Vaginal dryness, itching, burning, or frequent infections
  • Dry skin
  • Constipation
  • Nasal dryness

  It doesn't sound fun. If questioning during a medical history reveals positive responses to these questions, a referral to a rheumatologist is in order. This patient may have Sjögren's syndrome, as pointed out above.

  Dentistry can do a lot for people with salivary issues. Elsie, Kevin and Yehor needn't be sent away with a button for treatment. Know what you're dealing with and treat it.

  About the Author

  Shirley Gutkowski, RDH, BSDH, FACE, has been a practicing dental hygienist since 1986. She is codirector of CareerFusion (www.careerfusion.net). Gutkowski's new book “The Purple Guide: Confronting Caries” is available at www.rdhpurpleguide.com. She can be reached at [email protected].

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  Determining a Patient's Salivary Flow

  Testing salivary flow is the first step after taking a health history. To get the most accurate reading, a one-hour fast is recommended. That includes a fast from polishing. A salivary flow rate should be completed before any other procedure or the results will not be accurate. Resting salivary flow rate is measured by asking the patient to continually spit into a small graduated medicine cup over one minute. The average amount of saliva expelled by a healthy person is 1/3 ml/min. Less than that is a problem.

  The second test is the stimulated salivary test. The patient is asked to chew a soft paraffin cube for one minute, then their saliva is collected for the next five minutes. A healthy person will produce about 5 ml or more saliva during that five minute time span. Less than an average of 1 ml/min (math is involved) is cause for concern.

  A person with xerostomia will come in at normal for stimulated flow rate. If that's the case, palliative methods may be all that's necessary. Other helpful ways to make a person with xerostomia more comfortable may be to increase hydration. Drinking, or eating more foods that contain water, such as raw vegetables and fruits, can help.

  On the other hand, a person with hypofunction of the salivary glands may require a biopsy to determine the cause, unless the cause is already apparent from the combination of the salivary flow rate test in the office and the health history.