XEROSTOMIAPhysiology, Etiology, Epidemiology,

Pathogenesis, Diagnosis, and Treatment

Reviewed by:

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.

XEROSTOMIA

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

DEFINITION OF XEROSTOMIA“Xero” = Dry & “Stomia” = Mouth

• Subjective complaint of patient• Diagnosis based on patient complaint and history• Salivary flow can be measured but no normal limits have been established

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

XEROSTOMIAProduction of Saliva

NORMAL FUNCTION OF SALIVA3

• 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

Salivary glands

Neural innervation

Cause one of two divisions

Sympathetic Parasympathetic

Causes very dry, thick, ropy saliva

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

Mechanisms of Salivary Production3

• Serous: very thin and watery• Mucous: very thick and viscous• Mixed secretions: mixture of the

two

XEROSTOMIASalivary Gland Classifications by Secretion3

XEROSTOMIASalivary Gland Classifications by Secretion3

• Serous: very thin and wateryo parotid glando lingual glands of von Ebner

(serous glands of von Ebner)

• Mucous: very thick and viscous• Mixed secretions: mix of the two

Serous acini

XEROSTOMIASalivary Gland Classifications by Secretion3

• Serous: very thin and watery• Mucous: very thick and viscous

o palatine glandso posterior lingual glandso labial buccal glands

• Mixed secretions: mix of the two

Mucous acini

• Serous: very thin and watery• Mucous: very thick and viscous• 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

XEROSTOMIASalivary Gland Classifications by Secretion3

Mixed: mostly serous acini (dark), partially mucous acini

(light cells)

• Major glands o Secrete saliva intermittently

• Minor glands o Secrete saliva continuously

Salivary Gland Classifications by Major or Minor Glands3

XEROSTOMIA

• Parotid gland3,4

o Largest of the 3 major glandso Produces 30% of total saliva output

Parotid duct is also known as Stenson’s duct Parotid/Stenson’s duct exits opposing

the maxillary second molaro Located anterior but inferior to the

external auditory meatuso Innervated by sympathetic and

parasympathetic divisions o Secretes serous type saliva

The Major Glands

XEROSTOMIA

Parotid gland

• Submandibular gland3,4

o Second largest salivary glando 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

o Located in a depression on the lingual side of the mandibular body

o Innervated by parasympathetic nerve endings and possesses NO sympathetic receptors

o The parasympathetic fibers arrive through the facial and glossopharyngeal nerves

o Mixed secretion – mostly serous

XEROSTOMIAThe Major Glands

Submandibular gland

• Sublingual glands3,4

o Smallest of the major glandso 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

The Major Glands

XEROSTOMIA

Sublingual gland

Minor salivary glands are found throughout the mouth: – Lips– Buccal mucosa (cheeks)– Alveolar mucosa (palate)– Tongue dorsum and ventrum– Floor of the mouth

Together, they play a large role in salivary production.

XEROSTOMIAThe Minor Salivary Glands3

• Unstimulated Flow (resting salivary flow―no external stimulus)o Typically 0.2 mL – 0.3 mL per minuteo Less than 0.1 mL per minute means the person has hyposalivation

Hyposalivation – not producing enough saliva

• Stimulated Flow (response to a stimulus, usually taste, chewing, or medication [eg, at mealtime])o Typically 1.5 mL – 2 mL per minuteo Less than 0.7 mL per minute is considered hyposalivation

Salivary Flow3

XEROSTOMIA

• 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

XEROSTOMIASalivary Flow3

• 90% of saliva is water• 10% is composed of inorganic and organic ions, and cellular

componentso 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

XEROSTOMIASalivary Composition1

As saliva passes through the salivary ducts, cations (sodium and chloride) are reabsorbed into the adjacent blood vessels.

XEROSTOMIAIons 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.

XEROSTOMIAIons 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)

XEROSTOMIAIons and Salivary Flow3

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.

XEROSTOMIAFluoride and Saliva3

Enzymes:o Amylase – converting starch into glucose and fructoseo Lysozymes – prevents bacterial infections in the moutho Histatins – prevents fungal infectionso Secretory IgA – immunity mediatoro Lactoperoxidases – stimulation of minor salivary glandso RNase and Dnase – cellular maintenanceo Lipase – initiates digestion of fato Kallikrein – vasoreactive substances

XEROSTOMIAOrganic Components of Saliva3

The cellular composition consists of:

o Epithelial cellso Neutrophilso Lymphocyteso Bacterial flora

XEROSTOMIACellular Composition of Saliva3

• 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)

• 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)

Factors that Affect Salivary Flow

XEROSTOMIA: Epidemiology

• Antacid• Antianxiety• Anticholinergic• Anticonvulsant• Antidepressant• Antiemetic• Antihistamine• Antihypertensive• Antiparkinsonian• Antipsychotic

Factors that Affect Salivary FlowXEROSTOMIA: Epidemiology

•Bronchodilator•Cholesterol reducing•Decongestant•Diet pills•Diuretic•Hormonal replacement therapy•Muscle relaxant•Narcotic analgesic•Sedative

Over 400 Medications Can Produce the Side Effect of Xerostomia7

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 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 “Dry Mouth”

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 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: Etiology Global Prevalence

“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

• 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 Symptoms3,5

• 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 Signs3,5

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 Two Approaches

• Perform oral hygiene at least 4 times daily, after each meal and before bedtimes• Use fluoride toothpaste• Rinse with a salt and baking soda solution 4 to 6 times daily• Avoid citrus juices (oranges, grapefruit, tomatoes)• Rinse and wipe oral cavity immediately after meals• Keep water handy to moisten the mouth at all times• Avoid liquids and foods with high sugar content• Avoid rinses containing alcohol and salty foods• Brush and rinse dentures after meals • Apply prescription-strength fluoride get at bedtime as prescribed• Use moisturizers regularly on the lips • Try salivary substitutes or artificial saliva preparations

XEROSTOMIA: Diagnosis Simple Management Strategies for Patients3,14

Some patients are predisposed to candidiasis because of the lack of salivary histatins

• Recommendation: o Antifungal medication can be recommended to control fungal growth

Denture patients also face challenges o Dentures do not adhere to the tissues and are not retained as wello Lack of lubrication increases the frictional forces between the dentures and the oral mucosa,

causing soreso Alveolar bone continues to resorb throughout life―dentures no longer fit properlyo Denture wearers are prone to inflamed tissues, called denture stomatitis (usually fungal)

• Recommendation: o Be sure the denture correctly adapts to the denture-bearing tissueso Optimize the patient’s tissue healtho Apply oral lubricants or saliva substitutes just before eating

XEROSTOMIA: Management

Treatment Challenges14

XEROSTOMIA: Management Treatment of Xerostomia-Associated Problems14

XEROSTOMIA: Management Treatment of Xerostomia-Associated Problems14

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

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, 19963. 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):29- 33.7. 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: References

This IFDEA Educational Teaching Resource was underwritten by an unrestricted grant from:

 

XEROSTOMIA