What is Dry Mouth ? Many individuals complain of mouth dryness. Dry mouth or xerostomia can be caused by decreased salivary flow or may be due to a sensation of dryness without decreased flow. Most Sjögren’s syndrome patients experience dry mouth because of decreased salivary flow. The only way to determine the degree of dry mouth with any degreeof certainty is by objective testing.
Some causes of dry mouth includes:
- Mouth breathing
- Dehydratation which can be caused by excess caffeine consumption
- Prescription medications, such as: analgesics, anti-cholinergics, stomach acid pump inhibitors, cholesterol-lowering drugs, anti-hypertensives, antidepressants, antihistamines, sleep aids, anti-Parkinson’s medication.
- Medical treatments: Head and neck radiation therapy or bone marrow transplantation
- Chronic conditions: Amyloidosis, Diabetes, Depression, Sarcoidosis, Hepatitis C, HIV, Sjögren’ syndrome
Saliva has a number of functions which are easily overlooked when saliva production is not an issue, including:
- Saliva keeps your mouth wet during sleep so that the tissues stay moist, hydrated and infection free.
- Saliva contains enzymes that begin the first phase of digestion.
- Saliva helps food form into a bolus so that it can be easily swallowed.
- Saliva produces the stickiness or sliminess needed to allow dentures to adhere to the mucosal tissue.
- Saliva is necessary to moisten the tongue, teeth and the mucosal tissues so that food can slip over these tissues.
- Saliva is necessary for proper speech and to keep normally wet tissues, such as lips, from feeling burnt, dry and chapped.
Salivais is necessary to dissolve food so that food can be tasted. In the absence of saliva, as in the case of Sjögren’ syndrome, most individuals find themselves drinking fluids with meals in order to enhance taste and to aid in swallowing safely.
Indications of Dry mouth
Saliva is a key component in oral health. Dry mouth symptoms include:
- Frequently sipping liquids
- Pain or discomfort when swallowing
- Speech difficulties
- Mouth dryness and discomfort
- Altered sense of taste
- Mouth and salivary gland infections
- Increased tooth decay
- Discomfort wearing dentures / appliances
- Absence or frotty thick saliva
- Cracking at the corners of the lips (angular chelitis)
Diagnosing Dry mouth
Dry mouth is uncomfortable and can be painful, and importantly , it can lead to other problems or indicate more serious disease such as Sjögren’s syndrome. If you suspect dry mouth, it is important to be tested.
Research has shown that it requires about a 50% loss of saliva for individuals to become aware of having dry mouth. Thus, there may or may not be signs of dry mouth in its early stages. In its milder form, the tissues may appear normal. Individuals are able to eat and speak without difficulty and usually do not have problems with tooth decay. The oral ecological balance is usually maintained and there is often no issue with secondary bacterial or viral infections. Mild oral dryness often occurs in individuals using long-term medication for medical issues such as high blood pressure. It can also be seen in individuals with fibromyalgia.
The more severe forms of dry mouth are usually seen in individuals who are using large doses of psychotropic medication, large doses of analgesics including opioids and in individuals with Primary Sjögren’s syndrome where salivary flow can sometimes reduce to zero.
When salivary flows lessen, the tongue and other mucosal tissues are often infected with yeast (candidiasis), causing baldness of the surface of the tongue and redness of the mucosal tissue. These areas can ulcerate and become very painful. When there is infection on the tongue, taste can diminish and eating can become very difficult and less enjoyable because of pain and loss of taste. Individuals tend to avoid spicy or scratchy foods, which can irritate the mucosal tissue. These changes are reversible with treatment.
Much less reversible are the changes that occur to the teeth. With the loss of saliva, including both its mechanical cleaning and its antibacterial, antiviral, and antifungal properties and with the subsequent increase in bacterial load and decrease in oral pH, the teeth can begin to demineralize and decay quickly. There may come a time when the teeth are non-restorable when decay affects large area of the tops, bottoms, or sides of the teeth. When extensive teeth may fracture, leaving decayed roots and fragments of decayed teeth resulting in infection and pain. Sometimes the only choice is extraction and replacement with implants or a dental prosthesis, which may be implant-supported.
Connective Tissue Disorders
Sjögren’s syndrome can occur alone (Primary Sjögren’s syndrome) or as a complication in connective tissue disorders such as Rheumatoid Arthritis (RA) and Systemic Lupus Erythematosis (SLE). Although this with Secondary Sjögren’s syndrome also experience dry mouth, the dryness is not usually as severe as it is in Primary Sjögren’s syndrome. In Primary Sjögren’s syndrome, specific antibodies are produced against salivary gland tissue and other exocrine glands, including the lacrimal or tear glands. As a result of the loss of salivary gland tissue, mouth dryness becomes severe.
What should you do if dry mouth is suspected ?
If you think you have dry mouth, it is important to see your dentist or physician and inform them of your concern. You must remember that even if your mouth does not look dry, it may still be dry. You should ask your physician to run blood tests to look for evidence of a connective tissue disorder, blood loss, or nutritional deficiency. A salivary uptake scan can be helpful in the investigation.
You might also discuss a referral to rheumatologist for a workup if Sjögren’s syndrome or other connective tissue disorder is suspected. A minor salivary gland lip biopsy may be ordered to assist in diagnosing Sjögren’s syndrome.
Salivary flows: Testing starts with very simple measures including measuring oral acidity (oral pH); salivary buffering capacity and measuring salivary flow. Salivary flow is measured by assessing the flow of saliva from the patient’s mouth in a set amount of time. Unstimulated whole salivary flows tests use no stimulus while stimulated salivary flow is measured while you chew a piece of paraffin or gum. A low oral pH, low salivary buffering capacity and low instimulated or stimulated flows are objective evidence of dry mouth. Low unstimulated or resting flow usually means dry mouth at night; low stimulated flow usually suggest difficulty eating without supplemental fluid.
Blood tests: Blood testing can be done to look for evidence of systemic disease, including Sjögren’s syndrome.
Salivary scans: Following a finding of low clinical salivary flows, low pH or low salivary buffering capacity, a salivary uptake scan can be done. During this test, Tc99m (Technium 99) is injected and its uptake measured in the major three salivary glands (parotid, submandibular, sublingual glands). Discharge of saliva can be determined after stimulation with lemon juice.
Other imaging: A finding of an abnormal salivary scan may be followed by MRI or CT scan investigation of the glands to look for stones, cysts or infection, or other problems if suspected.
Dry mouth management
Simple measures include using sugarless candy or gum to stimulate salivary flow. Medications such as sialogogues, including pilocarpine and bethanechol may be prescribed for stimulation of the salivary glands, however, they may not be effective if there is not sufficient salivary gland tissue remaining or if side effects are experienced with these medications. Many over-the-counter products may also be helpful, including artificial saliva and newer products which claim to bind to the tissues increasing their wetness.
Products for dry mouth may include:
- Limited use of chlorhexadine rinse to reduce bacterial load in the mouth and increase oral pH.
- High fluoride containing toothpaste which can substitute at least once a day for regular toothpaste.
- Recalcifying products, such as MI Paste and X-PUR help to re-mineralize teeth that are at risk because of low pH. Sometimes these may be used with soft bleaching type trays during the night to stimulate saliva. The trays may also provide protection against tooth wear during bruxism (tooth grinding) and against tooth erosion due to acid reflux and low oral pH.
- A small amount of medication to increase salivary flow during sleep, such as pilocarpine or bethanechol.
- Using 100% xylitol containing products (granulated, gum, mints or discs) to reduce caries producing bacterial activity.
- Avoid burning or irritating toothpastes or mouthwashes. Use non-irritating products sush as PreviDent5000 plus, Control Rx, Biotene products or xylitol toothpastes.
Visiting the dentist
If you do have a problem with mouth dryness, especially if it is associated with a lowered pH and risk of increased decay, you should see your dentist and / or dental hygienist every three to four months for examination and restoration of early caries (cavities). Professional fluoride treatment including fluoride varnish can be done at these times. In addition, if there are signs of dental erosion or tooth wear, review of nutrition and oral hygiene practices may be helpful.
How you can help yourself
- Avoid caffeine
- Limit the frequency of sugar and soda consumption since caries risk increases with frequency of sugar exposures.
- Avoid acidic foods and beverages
- Keep mouth hydrated
- Take extra care and particular attention to good oral hygiene habits
- Stimulate natural saliva by chewing sugar-free gum, sucking sugar-free candies
- Use an electric toothbrush
- Treat acid reflux
- Humidify the house and office with a cool mist humidifier
The best way to help yourself is by joining an organization such as Sjögren’s Society of Canada so that you can be kept up to date about ongoing trials and new medications and products. The Sjögren’s Society of Canada can provide support and resource materials that will be helpful for you dentists / physicians.
To learn more about Sjögren’s syndrome, please contact the:
304-31 Mechanic Street
Paris, Ontario, N3L 1K1