Xerostomia

Introduction

Xerostomia is defined as dry mouth resulting from reduced or absent

saliva flow. Xerostomia is not a disease, but it may be a

symptom of various medical conditions

Etiology Xerostomia does not appear to be related to

age itself as much as to the potential for elderly to be taking medications that cause Xerostomia as a side effect.

May be a side effect of a radiation to the head and neck

a side effect of a wide variety of medications.

It may or may not be associated with decreased salivary gland function.

Normal salivary function is mediated by the muscarinic M3 receptor. Stimulation of this receptor results in increased watery flow of salivary secretions. When the oral mucosal surface is stimulated, afferent nerve signals travel to the salivatory nuclei in the medulla.

Functions of saliva

Saliva possesses many important functions including antimicrobial activity, mechanical cleansing action, control of pH, removal of food debris from the oral cavity, lubrication of the oral cavity, remineralization and maintaining the integrity of the oral mucosa.

Complications associated with xerostomia

Some common problems associated with xerostomia include :

a constant sore throat, burning sensation, difficulty speaking and swallowing, hoarseness and/or dry nasal

If left untreated, xerostomia decreases the oral pH and significantly increases the development of plaque and dental caries.

Oral candidiasis is one of the most common oral infections seen in association with xerostomia.

Signs and symptoms of xerostomia Individuals with xerostomia often complain of problems with eating, speaking, swallowing and

wearing dentures. Dry, crumbly foods, such as cereals and crackers,

may be particularly difficult to chew and swallow. Denture wearers may have problems with denture

retention, denture sores and the tongue sticking to the palate.

Patients with xerostomia often complain of taste disorders (dysgeusia), a painful tongue (glossodynia)

an increased need to drink water, especially at night.

Xerostomia can lead to markedly increased dental caries, parotid gland enlargement, inflammation and fissuring of the lips (cheilitis), inflammation or ulcers of the tongue and buccal mucosa, oral candidiasis, salivary gland infection (sialadenitis), halitosis and cracking and fissuring of the oral mucosa

Diagnosis and evaluation of xerostomia

Diagnosis of xerostomia may be based on evidence obtained from the patient's history,

an examination of the oral cavity and/or sialometry, a simple office procedure that measures the flow rate

of saliva. Xerostomia should be considered if the patient

complains of dry mouth, particularly at night, or of difficulty eating dry foods such as crackers.

When the mouth is examined, a tongue depressor may stick to the buccal mucosa.

In women, the "lipstick sign," where lipstick adheres to the front teeth, may be a useful indicator of xerostomia.

The oral mucosa may be dry and sticky, or it may appear erythematous due to an overgrowth of Candida albicans.

The red patches often affect the hard or soft palate and dorsal surface of the tongue.

Occasionally, pseudomembranous candidiasis will be present, appearing as removable white plaques on any mucosal surface.

There may be little or no pooled saliva in the floor of the mouth, and the tongue may appear dry with decreased numbers of papillae.

The saliva may appear stringy, ropy or foamy. Dental caries may be found at the cervical margin or neck of the teeth, the incisal margins or the tips of the teeth

Estimating the the function of salivary glands Sialometry, or salivary flow measurement, collection devices are placed over the

parotid gland or the submandibular/sublingual gland duct orifices, and saliva is stimulated with citric acid.

Values less than 0.1 mL/min are typically considered xerostomic, although reduced flow may not always be associated with complaints of dryness.

SialographyIt is an imaging technique that may be useful

in identifying salivary gland stones and masses.

It involves the injection of radio-opaque media into the salivary glands.

Salivary scintigraphycan be useful in assessing salivary gland

function. Technetium-99m sodium pertechnate is intravenously injected to ascertain the rate and density of uptake and the time of excretion in the mouth.

Salivary gland biopsy Minor salivary gland biopsy is often used in

the diagnosis of Sjögren's syndrome (SS) human immunodeficiency virus-salivary

gland disease, sarcoidosis, amyloidosis and graft-vs.-host disease. Biopsy of major salivary glands is an option

when malignancy is suspected.

Common causes of xerostomia

Medications More than 400 commonly used drugs can cause

xerostomia. The main culprits are antihistamines, antidepressants, anticholinergics,

anorexiants, antihypertensives, antipsychotics, anti-Parkinson agents, diuretics and sedatives.

Other drug classes that commonly cause xerostomia include antiemetics, antianxiety agents, decongestants, analgesics, antidiarrheals, bronchodilators and skeletal muscle

Diseases and other conditions

The most common disease causing xerostomia is

Sjögren's syndrome (SS), a chronic inflammatory autoimmune disease that occurs predominantly in postmenopausal women.

SS is characterized by lymphocytic infiltration of salivary and lacrimal glands, resulting in xerostomia and xerophthalmia.

Sarcoidosis and amyloidosis are other chronic inflammatory diseases that cause xerostomia. In sarcoidosis, noncaseating epithelioid granulomas in salivary glands result in reduced salivary flow. In amyloidosis, amyloid deposits in the salivary glands result in development of xerostomia

HIV-salivary gland disease occurs in some individuals infected with HIV, mainly in children. This disease results in enlargement of the parotid glands and, occasionally, the submandibular glands, resulting in xerostomia. The T-lymphocyte infiltrate is mainly comprised of CD8+ cells, as compared with SS where CD4+ cells predominate

Other systemic diseases that can cause xerostomia include

rheumatoid arthritis, systemic lupus erythematosus, scleroderma, diabetes mellitus, hypertension, cystic fibrosis, bone marrow transplantationendocrine disorders nutritional deficiencies, nephritis, thyroid dysfunction and neurological diseases such as Bell's palsy and

cerebral palsy

. Hyposecretory conditions, such as primary biliary cirrhosis, atrophic gastritis and pancreatic insufficiency, may also cause xerostomia.

Dehydration resulting from impaired water intake, emesis, diarrhea or polyuria can result in xerostomia.

Psychogenic causes, such as depression, anxiety, stress or fear, can also result in xerostomia. Alzheimer's disease or stroke may alter the ability to perceive oral sensations.

Dry mouth is often exacerbated by activities such as hyperventilation, breathing through the mouth, smoking or drinking alcohol.

Trauma to the head and neck area can damage the nerves supplying sensation to the mouth, impairing the normal function of the salivary glands

Management of xerostomia

the management of xerostomia will include identification of the underlying cause. Symptomatic treatment typically includes

four areas: increasing existing saliva flow, replacing lost secretions, control of dental caries and specific measures such as treatment of

infections.

Self-care

Patients should be encouraged to conduct a daily mouth examination, checking for red, white or dark patches, ulcers or tooth decay. If anything unusual is found it should be reported to their physician or dentist.

Patients should be encouraged to practice regular preventive dentistry.

Plaque removal and treatment of gingival infections or inflammation and dental caries are essential.

Patients should also be counseled to brush and floss regularly and to use fluoride daily. The teeth should be cleansed at least twice daily using a soft bristled toothbrush and mildly flavored low-abrasive fluoride toothpaste

Products containing sodium lauryl sulfate should be avoided as they may contribute to the formation of aphthous ulcers or canker sores.

Sodium fluoride rinses should be held in the mouth for at least one minute before expectorating,

fluoride gels can be applied with a toothbrush and left in place for two to three minutes before expectorating.

Chlorhexidine rinses also may be useful in preventing caries by reducing lactobacillus counts in the mouth.

Dentures should not be worn during sleep and should be kept clean by overnight soaking.

Acrylic appliances should be soaked in a sodium hypochlorite solution, and metal dentures should be soaked in chlorhexidine.

Patient may want to consider visiting their dentist more frequently and should take advantage of the opportunity to discuss their xerostomia with their dental hygienist

patients with xerostomia should avoid sugary or acidic foods or beverages.

These patients should also avoid irritating foods that are dry, spicy, astringent or excessively hot or cold.

If possible, tobacco and alcohol intake should be eliminated to control dental caries.

Lubricants such as Orajel® or Vaseline® and glycerin swabs on the lips and under dentures may relieve drying, cracking, soreness, and mucosal trauma.

A cold air humidifier may aid mouth breathers who typically have their worst symptoms at night.

Saliva stimulants or sialagogues, such as sugarless candies and chewing gum, may be used to stimulate saliva flow when functional salivary glands remain.

Patients should be advised to take frequent sips of water throughout the day and to suck on ice chips.

Eating foods such as carrots or celery may also help patients with residual salivary gland function.

Addition of flavor enhancers such as herbs, condiments and fruit extracts may make food more palatable to patients complaining of their food tasting bland, papery, salty or otherwise unpleasant.

Saliva substitutes

Artificial saliva or saliva substitutes can be used to replace moisture and lubricate the mouth.

Artificial salivas are formulated to mimic natural saliva, but they do not stimulate salivary gland production, they must be considered as replacement therapy rather than a cure

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