Whether you call it spit, spittle, dribble or drool, saliva is something we take for granted until it starts to go away. But before I get into the ins and out of dry mouth, I want to discuss a little about what saliva is.
What is saliva?
In terms of composition, it is a fluid secreted by large and small salivary glands in different areas of the mouth. It is predominantly water, but also is composed of electrolytes, mucus (mucopolysaccharides and glycoproteins), antibacterial compounds, epidermal growth factor, many types of enzymes with different functions, the analgesic Opiorphin, and Haptocorrin (which helps with the absorption of Vitamin B12) and other components as well.
In terms of function, saliva is important for not only oral health, but for overall health as well. Some of its functions are:
- to moisturize and lubricate the mouth and prevent dehydration
- it aids in digestion
- facilitates proper taste
- it assists in speech and swallowing
- it helps maintain the proper pH in the mouth to protect the teeth and soft tissue
- it helps to prevent the penetration of toxins and potential carcinogens into the oral tissues
- it has anti-bacterial, anti-viral, and anti-fungal functions
This is a brief and simplistic description of the very complex roles that saliva plays in our physical health.
It is no surprise then that dry mouth is something to take seriously. Dry mouth (also called Xerostomia) has been described as a symptom that acts like a disease. By definition, it is a reduction in the production of saliva that leads to a complaint of mouth dryness. It is said that 10% of the population has this symptom, with a higher rate among females than males.
I feel, however, that this definition is incomplete. First, because it takes an over 50% reduction in salivary output before most people will notice any mouth dryness at all. Many of the problems that can occur from decreased salivary output (salivary hypo-function) occur far below the 50% reduction level. Because of this fact, patient awareness of obvious dry mouth is not a reliable indicator of the condition. Second, because it is not just a reduction in salivary output, but also an alteration in its composition. Different salivary glands and cells within those glands are all affected differently by whatever is causing the salivary production to change. Because of this, the composition of saliva is altered, and so even with no change in volume its proper function is adversely affected.
Signs and symptoms of dry mouth
Some of the signs and symptoms that can occur from decreased output and altered salivary composition include:
- dryness of the mouth or throat
- saliva that seems thick or stringy
- frequent thirst
- difficulty speaking, chewing, and swallowing
- bad breath
- diminished or altered taste
- dry or cracked corners of the lip
- repeated mouth sores and ulcers
- gum tissue inflammation and disease
- increased rate of tooth decay
- change in the appearance of the tongue
- denture wearers suffering from more soreness and reduced retention of their appliances
- development of oral fungal infections
Causes of dry mouth
Xerostomia may be caused by many factors and conditions. Aging itself may involve some minor change in volume and composition of saliva. Most of the changes with aging though occur once compromises occur secondary to chronic and acute diseases that develop and the drugs used to treat and control those disease conditions. There are more than 500 medications that can contribute to dry mouth. Some of the classes of those medications are:
- muscle relaxants
- appetite suppressants
- opioid analgesics
Tobacco use of any kind and many recreational drugs also contribute to xerostomia.
Conditions that can cause mouth dryness include:
- certain auto-immune diseases (such as Sjogren’s syndrome, Rheumatoid Arthritis, and Systemic Lupus)
- cancer therapy such as radiation to the head and neck and chemotherapy
- surgical removal of the salivary glands
- injury or surgery that causes certain types of nerve damage
- certain cases of stroke
- snoring and sleep apnea
- hormonal imbalances
- anorexia and bulimia
Do you suffer from dry mouth? Here are some options.
So what can be done if you do suffer from dry mouth?
If the problem is related to medications, then the prescribing provider may be able to modify dosage or substitute a different medication to reduce the symptoms. Alternatively, it is sometimes possible to prescribe a medication to stimulate more saliva production. Drugs such as pilocarpine and cevimeline can help if not contra-indicated in your particular case. Chewing sugar-free gum or lozenges can help boost salivary production a little as well. There are also a variety of saliva substitutes that can offer palliative relief. The popular line of Biotene products can be found in most drug stores in their dental section. Also, a newer prescription product called SalivaMAX is now available to help provide a saliva substitute.
For preserving the health of the teeth in dry-mouth sufferers, a fluoride product of some form is often prescribed for topical use on the teeth to reduce the tendency for tooth decay to increase. Fastidious home care and avoidance of sugary or acidic foods and beverages is especially important with dry mouth, as well as avoiding unnecessary over-the-counter drugs, tobacco use and recreational drug use that will aggravate the effects of compromised salivary function.
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