XEROSTOMIA
Physiology, Etiology, Epidemiology,
Pathogenesis, Diagnosis, and Treatment
Reviewed by:
XEROSTOMIA
After viewing this lecture, attendees should be able to:
• describe the oral anatomy and physiology related to
salivary function as well as the role of saliva in the oral
cavity.
• discuss the etiology and epidemiology of xerostomia.
• relate treatment options for xerostomia.
DEFINITION OF XEROSTOMIA
“Xero” = Dry & “Stomia” = Mouth
Xerostomia can be defined as the subjective
sensation of oral dryness that may or may not be associated
with a reduction in salivary output.1,2 It can have profound
negative effects on the quality of life.3
• Subjective complaint of patient
• Diagnosis based on patient complaint and history
• Salivary flow can be measured but no normal limits have been established
XEROSTOMIA
Production of Saliva
Oral Glandular Tissue3
(saliva secreting)
Begins development at 6
weeks gestation and is
completed by about the 12th
week
The glandular tissue
continues to enlarge until
birth
NORMAL FUNCTION OF SALIVA3
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Hydrating–moisturizing
Cleansing
Lubrication
Digestion
Remineralization of dentition
(pH maintenance, buffering)
Maintenance of mucosal integrity
Immunity mediator
Antimicrobial (antifungal, antibacterial)
Stimulation of minor salivary glands
Cellular maintenance
Enables swallowing
Enables tasting
Enables speech articulation
XEROSTOMIA
Mechanisms of Salivary Production3
Salivary glands
Neural innervation
Cause one of two divisions
Sympathetic
Causes very dry, thick, ropy saliva
Parasympathetic
Causes thin, watery, profuse salivation
The two divisions work in opposition and have the ability to
physiologically alter the quality as well as the quantity of the saliva
XEROSTOMIA
Salivary Gland Classifications by Secretion3
• Serous: very thin and watery
• Mucous: very thick and viscous
• Mixed secretions: mixture of the
two
XEROSTOMIA
Salivary Gland Classifications by Secretion3
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Serous: very thin and watery
o parotid gland
o lingual glands of von Ebner
(serous glands of von Ebner)
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Mucous: very thick and viscous
Mixed secretions: mix of the two
Serous acini
XEROSTOMIA
Salivary Gland Classifications by Secretion3
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Serous: very thin and watery
Mucous: very thick and viscous
o palatine glands
o posterior lingual glands
o labial buccal glands
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Mixed secretions: mix of the two
Mucous acini
XEROSTOMIA
Salivary Gland Classifications by Secretion3
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Serous: very thin and watery
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Mucous: very thick and viscous
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Mixed secretions: mix of the two
o Sublingual glands
– Mostly mucous with some serous
o Submandibular glands
– Mostly serous with some mucous
o Anterior lingual glands
– Mixed secretion
Mixed: mostly serous acini
(dark), partially mucous acini
(light cells)
XEROSTOMIA
Salivary Gland Classifications by Major or Minor Glands3
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Major glands
o Secrete saliva intermittently
Minor glands
o Secrete saliva continuously
XEROSTOMIA
The Major Glands
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Parotid gland3,4
o Largest of the 3 major glands
o Produces 30% of total saliva output
 Parotid duct is also known as
Stenson’s duct
 Parotid/Stenson’s duct exits opposing
the maxillary second molar
o Located anterior but inferior to the
external auditory meatus
o Innervated by sympathetic and
parasympathetic divisions
o Secretes serous type saliva
Parotid gland
XEROSTOMIA
The Major Glands
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Submandibular gland3,4
o Second largest salivary gland
o Produces 65-70% of total saliva output
 The duct is called Wharton’s duct
 Wharton’s duct exits on the floor of the
mouth opposing the lingual surface of the
tongue
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Located in a depression on the lingual side
of the mandibular body
Innervated by parasympathetic nerve
endings and possesses NO sympathetic
receptors
The parasympathetic fibers arrive through
the facial and glossopharyngeal nerves
Mixed secretion – mostly serous
Submandibular
gland
XEROSTOMIA
The Major Glands
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Sublingual glands3,4
o Smallest of the major glands
o Produce less than 5% of total
saliva output
 Saliva delivered via the ducts of
Bartholin
 The Bartholin ducts exit on the
base of the lingual surface of the
tongue
o Innervated by parasympathetic
fibers
o Little or no sympathetic influence
o Mixed secretion – mostly mucous
Sublingual gland
XEROSTOMIA
The Minor Salivary Glands3
Minor salivary glands are found throughout the mouth:
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Lips
Buccal mucosa (cheeks)
Alveolar mucosa (palate)
Tongue dorsum and ventrum
Floor of the mouth
Together, they play a large role in salivary production.
XEROSTOMIA
Salivary Flow3
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Unstimulated Flow (resting salivary flow―no external stimulus)
o Typically 0.2 mL – 0.3 mL per minute
o Less than 0.1 mL per minute means the person has hyposalivation
 Hyposalivation – not producing enough saliva
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Stimulated Flow (response to a stimulus, usually taste, chewing, or
medication [eg, at mealtime])
o Typically 1.5 mL – 2 mL per minute
o Less than 0.7 mL per minute is considered hyposalivation
XEROSTOMIA
Salivary Flow3
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The average person produces approximately 0.5 L – 1.5 L per day
Salivary flow peaks in the afternoon
Salivary flow decreases at night when the parotid gland shuts down
There is a difference in the quality between stimulated and
unstimulated saliva
XEROSTOMIA
Salivary Composition1
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90% of saliva is water
10% is composed of inorganic and organic ions, and cellular
components
o sodium, potassium, and calcium are positive ions (cations)
o chloride, bicarbonate, and phosphates are negative ions (anions)
The cationic and anionic components play an important role in the
function of saliva
XEROSTOMIA
Ions and Salivary Flow3
As saliva passes through
the salivary ducts,
cations (sodium and
chloride) are reabsorbed
into the adjacent blood
vessels.
XEROSTOMIA
Ions and Salivary Flow3
As saliva passes through the salivary ducts, cations (sodium and chloride) are
reabsorbed into the adjacent blood vessels. In exchange, bicarbonates and
potassium are transferred from the blood vessels into the salivary ducts.
XEROSTOMIA
Ions and Salivary Flow3
Stimulated Salivary Flow
• Saliva passes through the salivary duct very rapidly (a negative result of fast
flow)
o It impedes the exchange of sodium and chloride for potassium and
bicarbonate
Unstimulated Salivary Flow
• Has a high content of potassium and bicarbonate (a positive result of slow
flow)
o The quality of unstimulated saliva will change when flow increases because
of a stimulus (chewing gum, thinking about lemons, looking at a food you
crave)
XEROSTOMIA
Fluoride and Saliva3
Fluoride is also secreted in saliva.
Unlike the ions in saliva, the fluoride content (level) is not altered whether
the salivary flow is simulated or unstimulated.
XEROSTOMIA
Organic Components of Saliva3
Enzymes:
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Amylase – converting starch into glucose and fructose
Lysozymes – prevents bacterial infections in the mouth
Histatins – prevents fungal infections
Secretory IgA – immunity mediator
Lactoperoxidases – stimulation of minor salivary glands
RNase and Dnase – cellular maintenance
Lipase – initiates digestion of fat
Kallikrein – vasoreactive substances
XEROSTOMIA
Cellular Composition of Saliva3
The cellular composition consists of:
o Epithelial cells
o Neutrophils
o Lymphocytes
o Bacterial flora
XEROSTOMIA: Epidemiology
Factors that Affect Salivary Flow
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Medication
Autoimmune disease (Sjogren’s syndrome, lupus)3
Systemic diseases (diabetes, asthma, kidney, sarcoidosis, HIV)3
Stress/anxiety/depression5
Radiation therapy to the head and neck3
– 30 Gy = glandular fibrosis (gland can still produce some saliva)
– 60-70 Gy = glandular destruction (gland can no longer produce saliva)
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Gender (70 % female, usually postmenopausal3)
Sympathomimetic medications (stimulate the sympathetic nervous system)6
Parasympatholytic medications (inhibit the parasympathetic nervous system)6
Circadian rhythms (decreases in the fall and increases in the spring)
XEROSTOMIA: Epidemiology
Factors that Affect Salivary Flow
Over 400 Medications Can Produce the Side Effect of Xerostomia7
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Antacid
Antianxiety
Anticholinergic
Anticonvulsant
Antidepressant
Antiemetic
Antihistamine
Antihypertensive
Antiparkinsonian
Antipsychotic
•Bronchodilator
•Cholesterol reducing
•Decongestant
•Diet pills
•Diuretic
•Hormonal replacement therapy
•Muscle relaxant
•Narcotic analgesic
•Sedative
XEROSTOMIA: Epidemiology
Factors that Affect Salivary Flow
Age2,8
o Studies show that among non-institutionalized people not taking medication,
neither the quantity or quality of saliva change significantly with age
o Studies show a positive correlation between the number of drugs taken and
the incidence and severity of xerostomia
XEROSTOMIA: Etiology
“Dry Mouth”
Xerostomia is the term used for the symptom of oral dryness.
While oral dryness is most commonly associated with a reduction
in salivary gland output (termed salivary gland hypofunction), the
symptom may be reported by patients with apparently normal
salivation who have changes in saliva composition.1
XEROSTOMIA: Etiology
Prevalence
Xerostomia affects 25% of the population and is becoming one of the
fastest-growing oral health problems in North America3,5
• Medications are the cause of more than 90% of xerostomia cases
• 32 million Americans today take three or more medications daily
• Xerostomia was not a great problem in the past because people did not
take as many medications as they do today5
XEROSTOMIA: Etiology
Global Prevalence
The reported prevalence of dry mouth varies widely due to
the methodological and population differences in various studies.
Prevalence has been estimated to range from 10% to 38%,9-12
with 20% the most commonly reported figure2,3
Xerostomia is becoming increasingly common in developed countries
where adults are living longer and poly-pharmacy is very common.13
XEROSTOMIA: Diagnosis
“The approach to managing the patient has to follow a logical
progression. It should be part of a comprehensive evaluation.
Symptoms should be noted and signs should be recognized in order to
properly diagnose the condition. Treatment should be based on all of
that gathered information.”5
– Joseph L. Perno, DDS, FAGD
XEROSTOMIA: Diagnosis
Symptoms3,5
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Viscous saliva
Sticky saliva
Difficulty speaking
Difficulty swallowing
Halitosis
Altered taste
Complaint of dryness
Complaint of burning mouth, lips, or tongue
Altered sense of smell
XEROSTOMIA: Diagnosis
Signs3,5
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Increased caries
Food sticking to the oral structures
Frothy saliva
Gingivitis
Absence of saliva
Cracking and fissuring of the tongue
Ulceration of oral mucosa
No pooling of saliva in the floor of the mouth
Recurrent candidal infections
A toothbrush, mouth mirror, or instrument that sticks to the soft tissues
Poorly fitting prostheses
XEROSTOMIA: Diagnosis
Two Approaches
Increase Salivary Flow
• Using drugs that mimic or stimulate the parasympathetic division of the
autonomic nervous system3
o These are typically only used for radiation therapy or Sjogrens’
syndrome-induced xerostomia
o They have adverse side effects including: sweating, urination, stuffy nose,
lacrimation, and abdominal pain.
• Using citric acid–containing lozenges and candy that are sugar-free1,5
o This approach may decrease the pH into an acidic range. Salivary pH is
between 6.0 and 7.0. The critical pH where enamel erosion begins to be
seen is reported to be below 5.5
Saliva Substitutes
• Over-the-counter products are indicated for medication-induced salivary
hypofunction or xerostomia3,5
XEROSTOMIA: Diagnosis
Simple Management Strategies for Patients3,14
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Perform oral hygiene at least 4 times daily, after each meal and before bedtimes
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Use fluoride toothpaste
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Rinse with a salt and baking soda solution 4 to 6 times daily
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Avoid citrus juices (oranges, grapefruit, tomatoes)
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Rinse and wipe oral cavity immediately after meals
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Keep water handy to moisten the mouth at all times
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Avoid liquids and foods with high sugar content
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Avoid rinses containing alcohol and salty foods
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Brush and rinse dentures after meals
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Apply prescription-strength fluoride get at bedtime as prescribed
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Use moisturizers regularly on the lips
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Try salivary substitutes or artificial saliva preparations
XEROSTOMIA:
Management
Treatment Challenges14
Some patients are predisposed to candidiasis because of the lack of salivary
histatins
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Recommendation:
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Antifungal medication can be recommended to control fungal growth
Denture patients also face challenges
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Dentures do not adhere to the tissues and are not retained as well
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Lack of lubrication increases the frictional forces between the dentures and the oral mucosa,
causing sores
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Alveolar bone continues to resorb throughout life―dentures no longer fit properly
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Denture wearers are prone to inflamed tissues, called denture stomatitis (usually fungal)
Recommendation:
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Be sure the denture correctly adapts to the denture-bearing tissues
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Optimize the patient’s tissue health
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Apply oral lubricants or saliva substitutes just before eating
XEROSTOMIA: Management
Treatment of Xerostomia-Associated Problems14
XEROSTOMIA: Management
Treatment of Xerostomia-Associated Problems14
XEROSTOMIA
GETTING INVOLVED IN DIAGNOSING XEROSTOMIA
CAN BE A
WINDOW TO YOUR PATIENTS’ OVERALL HEALTH
Diagnosing xerostomia is an important diagnostic tool for other
systemic diseases. The signs and symptoms of xerostomia are often associated with
and/or result from other conditions.
XEROSTOMIA: References
1. Fox PC. Dry mouth: managing the symptoms and providing effective relief. J Clin Dent. 2006;17(2):27-29.
2. Nederfor T. Xerostomia: Prevalence and pharmacotherapy. Wed Dent J Suppl 116: 1-70, 1996
3. Crossley H. Unraveling the mysteries of saliva: its importance in maintaining oral health. Transcript of a lecture presented on August 6 at
the 2006 AGD Annual Meeting & Exposition. Gen Dent. 2007;55)4):288-296.
4. Netter FH, Jansen JT. Atlas of Human Anatomy. 3rd ed. Teterboro, NJ: Icon Learning Systems; 2003.
5. Gater L. Understanding xerostomia. AGD Impact. 2008;June(Special Report):26-30.
6. Urquhart D, Fowler CE. Review of the use of polymers in saliva substitutes for symptomatic relief of xerostomia. J Clin Dent. 2006;17(2):2933.
7. Kroll B. Dry mouth. The pharmacist’s role in managing radiation-induced xerostomia. Pharma Pract. 1998;14:72-82.
8. Shirodaria S, Kilbourn T, Richardson M. Subjective assessment of a new moisturizing mouthwash for symptomatic management of dry
mouth. J Clin Dent. 2006;17(2):45-51.
9. O’Grady NP: Incidence of dry mouth complaint in Cork Dental Hospital population. Stoma (Lisb). 1990;2(17): 55-56, 58.
10. Osterberg T, Birkhed D, Johnannson C, Svanborg A. Longintudinal study of stimulated whole saliva in an elderly population. Scand J Dent
Res. 1992;100(6):340-345.
11. Thomson WM, Brown RH, Williams SM. Medication and perception of dry mouth in a population of institutionalized elderly people. NZ
Med J 106: 219-221, 1993
12. Locker D: Xerostomia in older adults: A longitudinal study. Gerodontology. 12:18-25, 1985.
13. Edgar WM, O’Mullane DM. Saliva and Oral Health. 2nd ed. London: British Dental Journal Brooks; 1996.
14. Turner MD, Ship JA. Dry mouth and its effects on the oral health of elderly people. J Am Dent Assoc. 2009;138(September–Special
Supplement):15S-20S.
XEROSTOMIA
This IFDEA Educational Teaching Resource was
underwritten by an unrestricted grant from: