Oral Health and Alzheimers Disease Part 2: Provision of Dental Care to Patients with Dementia/Alzheimer’s Disease

Provision of Dental Care to Patients with Dementia/Alzheimer’s Disease

Dementia is the general term for loss of cognitive function, affecting behavior and resulting in an inability to function normally. The capacity to remember, solve problems, and speak are among the changes that occur with dementia. Alterations in personality also often occur. The impact on the affected person, as well as those close to that person, can be devastating.

While the prevalence of dementia increases with age, dementia is not considered a component of normal aging. In Western societies, populations are aging, and therefore the number of persons who will be affected by dementia is likely to increase. This will place a burden on families, the health care system and society in general.

Several types of dementia are recognized, including Alzheimer’s disease (AD; the most common form), vascular dementia and frontotemporal dementia (more common in middle age versus older age). It is common for a person to have mixed dementia, when more than one type of dementia is present at the same time (see the previous companion essay in this series for additional information).

Among the challenges faced by persons with dementia, especially in the more advanced stages is self-care, which includes the ability to perform activities of daily living, and attending to one’s health care needs. Oral health is certainly included, both in terms of the ability of the affected individual to perform routine oral hygiene, and to access and tolerate dental treatment.

The oral health of persons with AD is poor as compared to an age and sex-matched cohort of persons without AD1Delwel S, Binnekade TT, Perez R, Hertogh C, Scherder EJA, Lobbezoo F. Oral hygiene and oral health in older people with dementia: a comprehensive review with focus on oral soft tissues. Clin Oral Investig 2018;22:93-108.. This review, which included 36 studies, identified a range of oral problems in older patients with AD, including gingival inflammation, periodontitis, Candida infection, mucosal lesions and reduced flow of saliva. Plaque accumulation was greater in older patients with AD, and the need for assistance with oral hygiene procedures was frequently reported.

Of note, the relationship of periodontitis and AD has been a focus of investigation. As compared to controls, patients with cognitive impairment/AD were observed to have increased generalized periodontitis (odds ratio of 5.81, 95% confidence internal = 1.14-29.68) and a greater number of deeper periodontal pockets (odds ratio of 8.43, 95% confidence internal = 4.00-17.76). In addition, there was a greater dental caries burden in the cases versus controls (odds ratio of 3.36, confidence internal = 1.20-9.43). These investigators noted that cause and effect could not be determined from this cross-sectional study2Holmer J, Eriksdotter M, Schultzberg M, Pussinen PJ, Buhlin K. Association between periodontitis and risk of Alzheimer’s disease, mild cognitive impairment and subjective cognitive decline: A case-control study. J Clin Periodontol 2018;45:1287-1298..

Several reviews have examined challenges associated with provision of oral health care to patients with dementia/AD. Friedlander and colleagues3Friedlander AH, Norman DC, Mahler ME, Norman KM, Yagiela JA. Alzheimer’s disease: psychopathology, medical management and dental implications. J Am Dent Assoc 2006;137:1240-1251. summarized the pathophysiology and clinical characteristics of AD. They emphasized that in AD, both behavioral changes and polypharmacy associated with age (resulting in reduced salivary flow) can lead to the rapid progression of oral diseases (caries, periodontal diseases). They emphasized the importance of prevention, for both the caregiver and patient, with use of saliva substitutes and anti-caries preparations as needed.

Subsequently, Mancini and colleagues4Mancini M, Grappasonni I, Scuri S, Amenta F. Oral health in Alzheimer’s disease: a review. Curr Alzheimer Res 2010;7:368-373. noted the paucity of information on clinical dental care of patients with AD. If dental disease progresses due to self-neglect, the resultant oral diseases can cause significant pain and be difficult to manage as AD advances. They stressed the importance of providing oral health care early in the course of disease, with the goal of establishing/re-establishing oral health. This approach can minimize the chance of developing oral diseases later in life, since as AD progresses the provision of dental care becomes more challenging. The need to maximize quality of life for persons with AD was emphasized.

A recent review of oral health care for persons with AD5Marchini L, Ettinger R, Caprio T, Jucan A. Oral health care for patients with Alzheimer’s disease: An update. Spec Care Dentist 2019;39:262-273. presents a more developed picture. Poor oral health is often seen in patients with AD, and poor oral health has been linked to increased risk for certain chronic disorders, including aspiration-related pneumonia. Of concern is the likelihood of experiencing severe pain associated with development of a dental abscess. The authors suggest that regular oral care should be part of the patients’ regular healthcare plan, and oral hygiene procedures must be part of a patient’s daily routine.

Some specific reports examining the occurrence of oral disease in persons with dementia/AD are informative. An analysis of tooth loss comparing older adults with and without dementia, all whom received continuous dental care, suggested that patients with dementia had more advanced oral disease than persons without dementia, but these difference did not always reach significance6Chen X, Shuman SK, Hodges JS, Gatewood LC, Xu J. Patterns of tooth loss in older adults with and without dementia: a retrospective study based on a Minnesota cohort. J Am Geriatr Soc 2010;58:2300-2307.. At baseline, patients with dementia demonstrated fewer remaining teeth (18 versus 20). Further, dementia patients demonstrated 27% of teeth with caries or only residual roots, which was greater than what was observed for the non-dementia patients (p<0.001). During the following four years, 37% of patients with dementia and 31% of patients without dementia lost at least one tooth (this difference was not significant). After 5 years, the patients with dementia lost an average of 1.21 teeth, versus 1.01 for patients without dementia (again, this difference was not significant).

A study from Turkey indicated that 70% of AD patients demonstrated inconsistent and erratic oral self-care7Hatipoglu MG, Kabay SC, Guven G. The clinical evaluation of the oral status in Alzheimer-type dementia patients. Gerodontology 2011;28:302-306.. A higher percentage of patients with AD failed to remove dentures at night and had a greater prevalence of denture-associated soft tissue pathology. A study of patients with vascular dementia in Italy again emphasized the poor oral health of persons with dementia8Bramanti E, Bramanti A, Matacena G, Bramanti P, Rizzi A, Cicciu M. Clinical evaluation of the oral health status in vascular-type dementia patients. A case-control study. Minerva Stomatol 2015;64:167-175.. Versus controls, the dementia patients had more decayed teeth, increased severity of periodontitis, as well as poor denture care and a greater number of mucosal lesions associated with their dentures. Another study from Italy9D’Alessandro G, Costi T, Alkhamis N, Bagattoni S, Sadotti A, Piana G. Oral Health Status in Alzheimer’s Disease Patients: A Descriptive Study in an Italian Population. J Contemp Dent Pract 2018;19:483-489. observed poor oral health in persons with AD, which increased in severity as the severity of AD increased. To provide oral health services to patients with AD, they suggested that specifically-trained oral health professionals were needed, and that this care must be coordinated with both medical providers and family members/caregivers.

One very important aspect of management of patients with AD is the ability to masticate and swallow food, which has direct implications for oral health care providers who treat patients with AD. The severity of AD has been shown to be associated with reduced muscle mass and reduced swallowing function10Takagi D, Hirano H, Watanabe Y, et al. Relationship between skeletal muscle mass and swallowing function in patients with Alzheimer’s disease. Geriatr Gerontol Int 2017;17:402-409.. Even mild AD is associated with reduced masticatory function11Campos CH, Ribeiro GR, Costa JL, Rodrigues Garcia RC. Correlation of cognitive and masticatory function in Alzheimer’s disease. Clin Oral Investig 2017;21:573-578.. However, oral rehabilitation that involved fabrication of removable prostheses resulted in improved chewing efficiency as well as improved quality of life for persons with AD12Campos CH, Ribeiro GR, Rodrigues Garcia RCM. Mastication and oral health-related quality of life in removable denture wearers with Alzheimer disease. J Prosthet Dent 2018;119:764-768..

Due to the cognitive changes associated with AD, as well as the many needs of persons with the disease, both self-care and access to an oral health provider can be challenging. A national study in Sweden examining utilization of dental services by patients with dementia indicated that once a diagnosis of dementia was made, utilization of dental services decreased13Fereshtehnejad SM, Garcia-Ptacek S, Religa D, et al. Dental care utilization in patients with different types of dementia: A longitudinal nationwide study of 58,037 individuals. Alzheimers Dement 2018;14:10-19.. The average number of annual dental visits per year decreased from 1.5 to 0.9 following the diagnosis (p<0.001). This decrease was seen for all types of procedures, with particularly large relative decreases for “examination risk assessment and dental health promotion” and “preventive care” (see Table 1). They observed a more pronounced decrease in individuals with rapidly progressing dementia, who also were frail. Teeth were lost more rapidly in patients taking more medications, those whose dementia declined rapidly and those with vascular dementia. These investigators were unable to determine cause and effect but concluded by urging the need for appropriate oral health care for persons with dementia.

Quality of life (QoL) is an important consideration for patients with AD, and their caregivers. Oral health QoL for AD patients is adversely affected by dental caries, periodontal disease and missing teeth. Loss of molar teeth adversely affected the ability to chew14Cicciu M, Matacena G, Signorino F, Brugaletta A, Cicciu A, Bramanti E. Relationship between oral health and its impact on the quality life of Alzheimer’s disease patients: a supportive care trial. Int J Clin Exp Med 2013;6:766-772.. The decay, missing and filled (DMFT) index (based on 28 teeth) was 23.6, with the majority of teeth being missing (N=14). Further, a study of oral health QoL in patients with mild AD indicated good agreement between patients and their caregivers15Campos CH, Ribeiro GR, Rodrigues Garcia RC. Oral health-related quality of life in mild Alzheimer: patient versus caregiver perceptions. Spec Care Dentist 2016;36:271-276. in their assessment of how QoL is affected.

A systematic review of approaches to improve oral health for patients with AD found only one published paper, a randomized controlled trial, that could be analyzed16Rozas NS, Sadowsky JM, Jeter CB. Strategies to improve dental health in elderly patients with cognitive impairment: A systematic review. J Am Dent Assoc 2017;148:236-245 e233.. This gap in our knowledge base must be corrected, as the number of AD patients will increase as the population ages. Provision of oral health care to persons with AD depends upon several factors, including:

1. The severity of cognitive impairment, and whether the patient can perform oral self-care.
2. Awareness on the part of caregivers regarding the importance of daily oral hygiene for the patient and arranging for regular dental visits.
3. Reinforcing for medical providers the need for patients with dementia/AD to receive regular dental care. The linkage between poor oral health and AD is illustrated by a recent report that identified virulence factors from the important periodontal pathogen Porphyromonas gingivalis as being implicated in the development of AD17Dominy SS, Lynch C, Ermini F, et al. Porphyromonas gingivalis in Alzheimer’s disease brains: Evidence for disease causation and treatment with small-molecule inhibitors. Sci Adv 2019;5:eaau3333..
4. Awareness on the part of oral health care providers regarding their role in caring for patients with AD. Provision of dental care to patients with AD is often challenging, and oral health care providers may not be prepared to manage affected individuals.

The actual provision of oral health care service is largely dependent upon the degree of impairment affecting the patient with AD. In 1985, Niessen and colleagues18Niessen LC, Jones JA, Zocchi M, Gurian B. Dental care for the patient with Alzheimer’s disease. J Am Dent Assoc 1985;110:207-209. provided a framework for provision of dental care, which remains relevant today. They stressed restoration of function and an emphasis on preventive care, with the need to maintain as many teeth as possible since use of a removable prosthesis may be difficult for the patient in the later stages of AD. Oral self-care may initially be performed by the patient, but can be expected to transfer to a care-giver, which can be a family member or a health aid. They stressed the need for dental appointments to be scheduled at a time during the day when the patient is most alert and cooperative. Shorter appointments are preferred, and patients with AD may be more comfortable if a family member or health aid is with them in the dental operatory. Exposure of intraoral radiographs may be challenging or not possible for patients with AD. If necessary, selective radiographs should be taken of areas where problems are suspected.

An index to assess the ability of a patient with AD to tolerate dental care was proposed (Table 2). The summative score would guide the treatment plan, with 0-3 not requiring modification, 4-7 requiring moderate alteration and 8-10 requiring major alteration. The approach to dental care should stress simplicity and long-term stability, always with an emphasis on prevention (assessment of salivary flow and saliva replacement, topical fluoride applications5Marchini L, Ettinger R, Caprio T, Jucan A. Oral health care for patients with Alzheimer’s disease: An update. Spec Care Dentist 2019;39:262-273., more frequent prophylaxis visits). This report mentioned the possibility of using sedation for patients that would otherwise find it difficult to tolerate dental treatment.

For more advanced AD, and more advanced dental problems, general anesthesia may be required19So E, Kim HJ, Karm MH, Seo KS, Chang J, Lee JH. A retrospective analysis of outpatient anesthesia management for dental treatment of patients with severe Alzheimer’s disease. J Dent Anesth Pain Med 2017;17:271-280.. A case series described 43 patients with AD who successfully received dental care under outpatient intravenous sedation/general anesthesia. There were no reported complications. However, this approach is logistically more complicated and expensive, but may be required for a subset of patients with advanced AD.

Dental care for persons with AD is yet another example of overlap of oral/dental disease and systemic disease. In the future, oral health care providers will be required to be ever more aware of this blurred boundary between dental and medical care and be prepared to help manage and provide care for patients with complex systemic diseases.

Table 1: Utilization of different dental service before and after a diagnosis of dementia, Sweden 2017-2015.

All differences (before vs. after) significant at p<0.01. Adapted from Fereshtehnejad et al 13Fereshtehnejad SM, Garcia-Ptacek S, Religa D, et al. Dental care utilization in patients with different types of dementia: A longitudinal nationwide study of 58,037 individuals. Alzheimers Dement 2018;14:10-19..

Table 2: Management of a patient with Alzheimer’s disease in the dental office.

Score would range from 0-10. Modified from Niessen et al, 1985. 18Niessen LC, Jones JA, Zocchi M, Gurian B. Dental care for the patient with Alzheimer’s disease. J Am Dent Assoc 1985;110:207-209.

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