Geriatric Dentistry: Integral Component to Geriatric Patient Care

台灣老年醫學 [Review Article] 暨老年學雜誌

Geriatric Dentistry: Integral Component to Geriatric Patient Care

第 3 卷第 3 期

Geriatric Dentistry: Integral Component to Geriatric Patient Care Chih-Ko Yeh2, Michael S. Katz3, Michèle J. Saunders1,3 Abstract Geriatric dentistry is the branch of dentistry that emphasizes dental care for the elderly population and focuses upon patients with chronic physiological, physical and/or psychological changes or morbid conditions/ diseases. Oral health reflects overall well being for the elderly population. Compromised oral health may be a risk factor for systemic diseases commonly occurring in age. Conversely, elderly patients are more susceptible to oral conditions due to age-related systemic diseases and functional changes/decay. Oral health evaluation should be an integral part of the physical examination, and dentistry is essential to qualify geriatric patient care. In this paper, we briefly review current issues and topics in geriatric dentistry that reinforce the need for interdisciplinary care/research of the elderly. (Taiwan Geriatrics & Gerontology 2008;3(3):182-192) Key words: geriatric dentistry, oral health, general health integral part of general health. In the

Introduction

elderly population poor oral health has been considered a risk factor for general

In the U.S. Surgeon General’s first Report on Oral Health in America, the

health problems. On the other hand, older

mouth is referred to as a mirror of overall

adults are more susceptible to oral

health [1], reinforcing that oral health is an

conditions or diseases due to an increase in

1

Geriatric Research, Education and Clinical Center, Audie L. Murphy Hospital Division, South Texas Veterans Health Care System, San Antonio, Texas, U.S.A. Departments of Dental Diagnostic Science2 & Medicine3, University of Texas Health Science Center at San Antonio, San Antonio, Texas, U.S.A. Correspondence: Dr. Chih-Ko Yeh GRECC (182), Audie L. Murphy Division South Texas Veterans Health Care System 7400 Merton Minter Boulevard San Antonio, Texas, 78229-4404 Email: [email protected]

182

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chronic conditions and physical/mental

geriatric dentistry and training curriculum

disabilities. With advances in oral health

content in the United States [3]. In brief,

promotion and oral disease prevention in

essential topics for geriatric dentistry

industrialized countries, more people

education include demographic aspects of

retain their natural teeth into their old age

aging, aging theories and biology,

as compared to a half-century ago. The

age-related changes in physiology and

number of edentulous elderly (>60 years

psychology, socio-economic status of the

old) in the U.S. has declined to 25% (vs.

elderly, common age-related diseases and

56% in 1957); and among the dentate

their management, impact of systemic

elderly, they have an average number of 19

diseases on oral health and its converse,

± 0.2 teeth [2]. Therefore, dental services

oral lesions/pathology in the elderly,

for the elderly are shifting from removable

treatment planning, delivery of oral health

prosthetic-centered care to comprehensive

services, nutrition in aging, and geriatric

treatment including restorative dentistry,

health education/promotion. Geriatric

periodontal therapy, oral surgery,

dental education should be taught both at

endodontics, and even cosmetic dentistry,

the predoctoral and postdoctoral level to

orthodontics and implants.

oral health providers, and other health care professionals such as physicians and

The dental management of the elderly

nurses, and to caregivers and patients.

population is different from that of the

In this review, we briefly discuss

general population because special considerations for age-related

current issues and topics in geriatric

physiological changes, complications of

dentistry. The purpose of this discussion is

chronic condition/therapy, increased

not to provide specific details on any one

incidence of physical/mental disabilities,

subject, but rather to emphasize the

and social concerns are required.

necessity for interdisciplinary approaches

Therefore, special knowledge, attitudes,

to geriatric patient care.

and skills are necessary to provide oral health care to the elderly. Geriatric

Effect of Aging on Oral Tissues

dentistry, as part of general dentistry,

(Gerontology of the Oral Cavity)

emphasizes dental care for the elderly Data on the effect of aging on oral

population and focuses upon older patients with chronic physiological, physical,

tissues are scarce. Often there is no clear

and/or psychological changes or disorders.

demarcation between normal physiological

We have previously reviewed the scope of

aging and pathological diseases. Losses of 183

台灣老年醫學 暨老年學雜誌

Geriatric Dentistry: Integral Component to Geriatric Patient Care

第 3 卷第 3 期

tooth translucency and surface details (e.g.

changes during aging. However, there may

perikymata and imbrication lines) are

be some specific changes in individual

common changes during aging. Abrasion,

tissues during aging, e.g., salivary gland

attrition, and erosion of teeth usually

function, taste, tactile sensation and

increase with advancing age [4]. The

swallowing [8-11]. The clinical

dental pulp becomes smaller because of

significance of these specific changes is

secondary dentin and pulp stone formation,

currently unclear. Research in oral health

and sometimes root canals become totally

during aging is still in an early stage and

sclerosed [5,6]. Losses of tooth support

further study in this area is necessary.

structures (periodontium) are also commonly seen in elderly patients [6,7].

Oral Health and General Health in the

An increased loss of epithelium attachment

Elderly

and alveolar bone in the elderly may be a Oral health has a critical impact on

result of an increase in dental plaque and calculus rather than chronic age-related

the functional, psychological, and

changes per se. It is not known whether

economic aspects of the overall quality of

older individuals are more susceptible to

life. Oral health affects the elderly with

periodontal infections compared to other

regards to diet and nutrition intake,

age groups. As gingival recession

psychosocial interaction, and general

increases, resulting in exposure of root

well-being. The oral cavity is a portal of

surfaces to the oral environment, the

entry for microbial infections. Common

prevalence of root surface caries increases

oral diseases such as periodontal diseases

in the dentate elderly population.

and dental caries are the result of bacterial plaque accumulation. Recent correlation

It should be noted that oral tissues are not limited to the teeth and supporting

studies have raised concerns about the

structures (periodontium) but also include

possible linkage between oral

salivary glands, temporomandibular joint,

infection/chronic inflammation and

orofacial/mastication muscles,

systemic disease development/progression

oropharyngeal mucosa, and oral

(Table 1) [12,13]. Bacteria from the oral

sensory/motor nerve systems. Current

flora have been recovered from infection

studies suggest that oral physiology is

sites in other organs of patients with

generally intact at older ages. Normally,

aspiration pneumonia or endocarditis. A

morphologically observed changes in oral

recent case report documented a

tissues do not cause dramatic functional

hemopoietic transplant recipient who 184

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developed Candida krusei sepsis from

factors for oral diseases and conditions.

pre-existing oral colonization [14],

Multi-pharmacy, physical impairment and

suggesting a direct linkage between oral

neurological/psychological changes are

infection and systemic infection. Oral

common among the elderly, resulting in

infection-induced chronic inflammation,

drug-associated oral diseases/conditions

i.e., periodontal disease, has also been

(e.g., dry mouth, gingival hyperplasia and

associated as a risk factor or predictor for

lichenoid reaction) and poor oral hygiene

several cardiovascular diseases because

due to physical disability and neglect

cytokines elicited by oral inflammation

(Table 2). Several studies suggested that 68-95%

might mediate the initiation/progression of these diseases [12,15]. Establishment of a

of persons 65 years or older take

causal relationship between oral health and

medication. The average number of drugs

these systemic diseases is currently an

(prescription and/or non-prescription) used

emerging research field in geriatrics.

by this group is 1.4 to 4.3 [16,17]. With physiological aging and multiple

The oral-systemic diseases linkage is a special health concern for the elderly

pathologies, elderly patients are more

since effective oral hygiene is usually

susceptible to drug interactions and

compromised in patients with physical and

adverse effects [18,19]. One profound side

neurological changes. Accordingly,

effect of multi-pharmacy is xerostomia

elimination of the oral flora burden should

(mouth dryness). Saliva is the primary oral

be emphasized for geriatric patient care. In

defense mechanism in maintaining tooth

addition, many systemic diseases and

structure against oral infections. Saliva

conditions have oral manifestations, which

contains multiple antimicrobial factors,

may be the initial sign of a number of

buffering systems, supersaturated calcium

clinical diseases. Oral examination and

phosphates, large lubricant molecules, and

oral health evaluation should be integrated

digestive enzymes. Salivary hypofunction

components of a routine physical

usually causes rampant and severe oral

examination.

diseases such as caries and Candida infection. Without adequate salivary

Risk Factors Associated with Oral

function, quality of life also is likely to be

Diseases and Conditions in the Elderly

compromised since salivary moisture offers lubrication for taste, speech,

Elderly patients, unlike their younger

chewing, and swallowing. In addition,

counterparts, experience additional risk

certain medications commonly prescribed 185

台灣老年醫學 暨老年學雜誌

Geriatric Dentistry: Integral Component to Geriatric Patient Care

第 3 卷第 3 期

for the elderly can cause enlargement of

cognitive deficits of Alzheimer’s Disease

gingival tissues (e.g., phenytoin sodium

or other dementias lose the ability to

and calcium channel blockers) or induce

perform proper oral hygiene. Poor oral

lichenoid reaction (e.g.,

hygiene leading to dental infections may in

hydrochlorothiazides and ACE inhibitors

turn further exacerbate agitation in

or angiotensin II receptor antagonists).

demented patients and impede medication

Although lichenoid lesions of the oral

effectiveness in patients with diabetes.

mucosa are usually benign and asymptomatic, a very small number of

Common Oral Diseases and

cases develop malignancy [20]. Today,

Conditions in the Elderly

with increasing numbers of new Similar to the general population,

therapeutic agents marketed by pharmaceutical companies, unexpected

caries and periodontal disease remain the

oral complications sometimes ensue. As a

two major dental problems in elderly

possible example, recent reports raise

patients (Table 3). As gingival recession

concerns that patients undergoing

increases, resulting in dental root surface

long-term bisphosphonate treatment for

exposure to the oral environment, the

metabolic bone disease or osteoporosis

prevalence of root surface caries increases

might be at risk for developing

in the dentate elderly population.

osteonecrosis of the jaw (called

Epidemiological studies in the United

bisphosphonate-related osteonecrosis of

States showed that more than 50% of older

the jaw; BRONJ) [21]. Clinically,

individuals (65 years and older) had

modification of prescribed medications is

experienced root caries [22]. In addition,

required for managing drug-related side

older persons frequently suffer from

effects such as lichenoid reactions or

recurrent or secondary coronal caries. In

xerostomia in the oral cavity. Additionally,

Taiwan as in other industrial countries, the

oral disease prevention may be required

prevalence of periodontitis and missing

for patients prior to prescribing

teeth increases with age [23]. Oral mucosa conditions also are more

bisphosphonates. Age-related disorders themselves

prevalent among elderly populations.

contribute to higher risks for oral condition

Candida infection and denture related

in the elderly. Diabetes is a risk factor for

lesions are common oral manifestations in

advanced periodontal disease and Candida

geriatric patients. The oral cavity of

infection. Patients who suffer from

elderly patients is also vulnerable to viral 186

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infection (e.g., Herpes simplex and Herpes

stroke. An alternative treatment plan (such

zoster), autoimmune-related disorders

as adding fluoride therapy) and instruction

(e.g., erosive lichen planus, pemphigus

should be given to these patients and their

vulgaris, pemphigoid), and burning mouth

caregiver/family advocates. Likewise, oral

(syndrome) due to immune dysfunction,

hygiene should be provided as part of

nutritional deficiencies, chronic conditions,

general hygiene for patients who have

and cognitive alterations. The incidence of

compromised cognitive function and live

oral cancers also increases with advancing

in long-term care facilities. Regardless of

age. Dentists and other health care

dentate status, it is recommended that the

professionals should recognize the oral

elderly make dental visits at least every six

manifestations of these disorders and

months for clinical re-evaluation and,

provide proper management.

depending upon ability to perform oral hygiene for prophylaxis. Those with

Special Consideration of Dental Care

reduced ability to perform oral self care

for Elderly Patients

should be seen more frequently for prophylaxis. Since denture-related and

Geriatric patients are generally

other oral mucosa lesions are common in

classified into three groups based on

the elderly, edentulous patients should be

functional living ability; functionally

periodically evaluated by dental

independent, frail, and functionally

professionals. Further, in the United

dependent. Special approaches and

States, many states have laws mandating

treatment goals for oral health are different

annual dental services to residents in

for each group [24,25]. Regardless of

nursing facilities by licensed dentists

functional status, the elimination of acute

and/or dental hygienists (e.g., Texas State

dental infection and pain should be

Senate Bill 34, 2001).

achieved for all elderly patients. Oral

Geriatric patients usually have at least

disease prevention is still the central focus

one age-related change and/or disorder that

for the elderly population as for other

may affect patient management and

patient populations. Special oral hygiene

treatment planning. Clinical conditions,

measures, however, are required for the

such as hypertension, anticoagulation

elderly. For example, toothbrush or dental

therapy, and hypoglycemia, can trigger

floss devices with larger handles may be

emergency crises during dental treatment.

provided to patients with limited manual

Patients with diabetes often have

dexterity resulting from arthritis and/or

cardiovascular diseases and are more 187

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Geriatric Dentistry: Integral Component to Geriatric Patient Care

第 3 卷第 3 期

susceptible to infection if the disease is not

weight loss should routinely be recorded

properly controlled. Although

for dental patients. We have demonstrated

controversial, antibiotic prophylaxis may

that one-third of physician consultations

be necessary for dental procedures in frail

resulted in an alteration in dental treatment

elders to prevent infection of replaced

plans and 8% of consultations led to

joints and cardiac prosthetic valves. While

commencing medical treatment [27]. While specific health problem

dental health care workers provide their professional judgment regarding these

management during dental treatment of the

special conditions, consultations with

elderly remains a real challenge for

other health professions are often required

dentists, treatment of oral diseases

to optimize patient care. All health care

themselves is equally challenging. Many

providers should be familiar with the

treatment modalities are still empirical.

treatment guidelines from professional

Cervical overhangs are a common problem

organizations to facilitate interaction

for interproximal restorations due to deep

among interdisciplinary care groups [see,

subgingival root caries. Dentists should be

e.g., the most recent Prevention of

aware of advances in dental materials and

Infective Endocarditis: Guidelines from

new treatment modalities for diseases

the American Heart Association (AHA)

commonly seen in geriatric patients.

[26]]. Unlike the former guideline, the new

Hybrid/resin ionomer is a newly developed

AHA guideline has limited preventive

restorative material that releases fluoride

antibiotic use prior to invasive dental

and is advocated for use in patients with a

procedures in patients with artificial heart

high caries risk [28]. Despite years of

valve, history of infective endocariditis,

effort in the area of prosthodontics,

certain specific and severe congenital heart

difficult problems remain associated with

diseases, and a cardiac transplant with

the treatment of full denture patients with

valve problem. Oral health providers, as

atrophic alveolar ridges. Clinicians and

part of the overall health care system, are

researchers continue their search for

often in the front line in detecting

solutions to oral health problems faced by

age-related morbid conditions/diseases

the geriatric population.

through routine oral examination. Medical Conclusion

history and evaluation, as well as vital signs, i.e., temperature, respiratory rate,

The elderly population is increasing

blood pressure, pulse rate and rhythm, as

in industrialized societies worldwide. With

well as presence of pain or significant 188

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the decline of caries and periodontal

his encouragement and support during the

diseases in the younger age groups, dental

preparation of this manuscript and Dr.

professionals will be expected to take care

Howard Dang for his thorough review and

of more elderly dentate patients. The

critiques of this manuscript. The authors

management of the elderly population

would like to acknowledge two sources of

differs from that of the general population

funding from the Bureau of Health

because of age-related physiological

Professions of the Health Resources and

changes, the presence of age-related

Services Administration of the United

conditions/diseases, increased incidence of

States Public Health Service: (1) Geriatric

physical and mental disabilities, and also

Training Regarding Physicians and

social and economic concerns. Geriatric

Dentists, 7/1/00-6/30/05, Grant

dentistry is a specialized multidisciplinary

#5D0-1HP00004; and (2) South, West, and

branch of general dentistry designed to

Panhandle Consortium Geriatric Education

provide dental services to elderly patients.

Center of Texas, 7/1/02-6/30/07, Grant

Today, oral changes occurring during

#D31-HP80001.

aging are not clearly understood. Many Reference

treatment modalities for geriatric patients are still experimental. Further studies in

1. U.S.Department of Health and Human

geriatric dentistry both at the clinical and basic science level are necessary. Oral

Services. Oral Health in America: A

health is linked to general well being for

report of the Surgeon General. (NIH

the elderly. Conversely, adverse oral health

Publication No. 00-4713). 2000.

has been identified as a risk factor for

Rockville, MD, U.S. Department of

several systemic disorders/diseases. Dental

Health and Human Services, National

care should be integrated into overall

Institute of Dental and Craniofacial

health management of all geriatric

Research, National Institutes of Health. 2. Centers for Disease Control and

patients.

Prevention (CDC). Retention of natural teeth among older adults − United

Acknowledgement

States, 2002. MMWR 2003; 52: The authors would like to thank

1126-229.

Liang-Jiunn Hahn 韓良俊 (Professor

3. Yeh CK, Hou LT, Katz MS, Saunders

Emeritus, School of Dentistry, College of

MJ: Geriatric dental education and

Medicine, National Taiwan University) for

training in the United States of 189

台灣老年醫學 暨老年學雜誌

Geriatric Dentistry: Integral Component to Geriatric Patient Care

第 3 卷第 3 期

11. Yeh CK, Johnson DA, Dodds MWJ:

America. J Med Edu 2003; 7: 340-6.

Impact of aging on human salivary

4. Mjör IA: Age changes in the teeth. In: Holm-Pedersen P, Löe H, eds.

gland function: a community-based

Geriatric Dentistry. Copenhagen:

study. Aging Clin Exp Res 1998; 10:

Munksgaard, 1986: 94-101.

421-8. 12. Hupp JR: Expanding oral-systemic

5. Morse DR: Age-related changes of the dental pulp complex and their

linkages: are we putting the cart before

relationship to systemic aging. Oral

the horse? Oral Surg Oral Med Oral

Surg Oral Med Oral Pathol 1991; 72:

Pathol Oral Radiol Endod 2007; 103:

721-45.

443-5. 13. Meurman JH: Dental infections and

6. Ship JA: The oral cavity. In: Hazzard WR, Blass JB, Halter JB et al, eds.

general health. Quintessence Int 1997;

Principles of Geriatric Medicine and

28: 807-11. 14. Westbrook SD, Kirkpatrick WR,

Gerontology. 5th ed. New York: McGraw-Hill Companies, 2003:

Freytes CO, et al: Candida krusei

1212-22.

sepsis secondary to oral colonization in a hematopoietic stem cell transplant

7. Mackenzie IC, Holm-Pedersen P, Karring T: Age change in the oral

recipient. Med Mycol. 2007; 45:

mucosa membranes and periodontium.

187-90.

In: Holm-Pedersen P, Löe H, eds.

15. Tonetti MS, Lang NP, Cortellini P, et

Geriatric Dentistry. Copenhagen:

al: Enamel matrix proteins in the

Munksgaard, 1986: 102-13.

regenerative therapy of deep intrabony defects. J Clin Periodontol 2002; 29:

8. MacDonald DE: Principles of geriatric

317-25.

dentistry and their application to the

16. Lewis IK, Hanlon JT, Hobbins MJ,

older adult with a physical disability.

Beck JD: Use of medications with

Clin Geriatr Med 2006; 22: 413-34.

potential oral adverse drug reactions in

9. Yeh CK: Introduction of geriatric Dentistry (Chinese). J NTU Dent

community-dwelling elderly. Spec

School Alumni Assoc 1996; 14: 14-25.

Care Dentist 1993; 13: 171-6. 17. Nolan L, O'Malley K: Prescribing for

10. Chamberlain CK, Cornell JE, Saunders MJ, Hatch JP, Shinkai RS, Yeh CK:

the elderly, part II. prescribing pattern:

Intra-oral tactile sensation and aging in

differences due to age. J Am Geriatr

a community-based population. Aging

Soc 1988; 36: 245-54. 18. Paunovich ED, Sadowsky JM, Carter

Clin Exp Res 2007; 19: 85-90. 190

Vol.3

No.3

Chih-Ko Yeh et al

Taiwan Geriatrics & Gerontology

P: The most frequently prescribed

impairments in older adults: oral health

medications in the elderly and their

considerations. Gen Dent 2000; 48:

impact on dental treatment. Dent Clin

555-65. 26. Wilson W, Taubert KA, Gewitz M, et

North Am 1997; 41: 699-726.

al: Prevention of Infective Endocarditis.

19. Jacobsen PL, Chavez EM: Clinical management of the dental patient

Guidelines From the American Heart

taking multiple drugs. J Contemp Dent

Association. A Guideline From the

Pract 2005; 6: 144-51.

American Heart Association Rheumatic Fever, Endocarditis, and Kawasaki

20. Mithani SK, Mydlarz WK, Grumbine FL, Smith IM, Califano JA: Molecular

Disease Committee, Council on

genetics of premalignant oral lesions.

Cardiovascular Disease in the Young,

Oral Dis 2007; 13: 126-33.

and the Council on Clinical Cardiology, Council on Cardiovascular

21. American Association of Oral and Maxillofacial Surgeons: American

Surgery and Anesthesia, and the

Association of Oral and Maxillofacial

Quality of Care and Outcomes

Surgeons, position paper on

Research Interdisciplinary Working

bisphophonate-related osteonecrosis of

Group. Circulation. 2007. 27. Jainkittivong A, Yeh CK, Guest GA,

the jaws. J Oral Maxillofac Surg 2007;

Cottone JA: Evaluation of medical

65: 369-76.

consultations in a predoctoral dental

22. Winn DM, Brunelle JA, Selwitz RH, et al: Coronal and root caries in the

clinical program.

Oral Surg Oral

dentition of adults in the United States.

Med Oral Pathol Oral Radiol Endod

J Dent Res 1996; 75: 642-51.

1995; 80: 409-13. 28. Christensen GJ: A new challenge-root

23. Peng TK, Yao JH, Shih KS, Dong YJ, Chen CK, Pai L: Assessment of

caries in mature people. J Am Dent

periodontal disease in an adult

Assoc 1996; 127: 379-80. 29. Touger-Decker R, Mobley CC:

population survey in Taipei city using CPITN and GPM/T indices. Zhonghua

Position of the American Dietetic

Ya Yi Xue Hui Za Zhi 1990; 9: 67-74.

Association: oral health and nutrition. J Am Diet Assoc 2007; 107: 1418-28.

24. Clinical decision-making in geriatric

30. Janket SJ, Jones J, Rich S: The effects

dentistry. Philadelphia: W.B. Saunders

of xerogenic medications on oral

Company, 1998.

mucosa among the Veterans Dental

25. Ship JA, Chavez EM: Management of

Study participants. Oral Surg Oral

systemic diseases and chronic 191

台灣老年醫學 暨老年學雜誌

Geriatric Dentistry: Integral Component to Geriatric Patient Care

第 3 卷第 3 期

Med Oral Pathol Oral Radiol Endod

dorsal surface of the tongue: the

2007; 103: 223-30.

correlation with the dental, periodontal and prosthetic status in elderly

31. Griffin SO, Griffin PM, Swann JL, Zlobin N: New coronal caries in older

subjects. Gerodontology 2006; 23:

adults: implications for prevention. J

157-63. 36. Petersen PE, Yamamoto T: Improving

Dent Res 2005; 84: 715-20.

the oral health of older people: the

32. Griffin SO, Griffin PM, Swann JL, Zlobin N: Estimating rates of new root

approach of the WHO Global Oral

caries in older adults. J Dent Res 2004;

Health Programme. Community Dent

83: 634-8.

Oral Epidemiol 2005; 33: 81-92. 37. Shulman JD, Beach MM,

33. Milward M, Cooper P: Periodontal disease and the ageing patient. Dent

Rivera-Hidalgo F: The prevalence of

Update 2005; 32: 598-4.

oral mucosal lesions in U.S. adults: data from the Third National Health

34. Lockhart SR, Joly S, Vargas K, Swails-Wenger J, Enger L, Soll DR:

and Nutrition Examination Survey

Natural defenses against Candida

(NHANES Ⅲ), 1988-1994. J Am Dent

colonization breakdown in the oral

Assoc 2004; 135: 1279-86. 38. Fantasia JE: Diagnosis and treatment

cavities of the elderly. J Dent Res

of common oral lesions found in the

1999; 78: 857-68.

elderly. Dent Clin North Am 1997; 41:

35. Wang J, Ohshima T, Yasunari U, et al:

877-90.

The carriage of Candida species on the

192