Dose-Response Meta-Analysis on Tooth Loss With the Risk of Cognitive Impairment and Dementia

Functional teeth and cognitive function among the Chinese elderly: The chain mediating effect of depressive symptoms and social participation

The objective of this study was to investigate the chain mediating effects of depressive symptoms and social participation between functional teeth and cognitive function based on the biopsychosocial model. Data from the 2018 China Health and Retirement Longitudinal Study were analyzed. The findings revealed a favorable connection between the lack of edentulism and cognitive function, persisting even when accounting for the mediating factors of denture usage, depressive symptoms, and social participation. Furthermore, the study identified six indirect pathways in this relationship. The present study has substantiated the correlation between edentulism and cognitive function, thereby proposing that interventions aimed at denture usage, depressive symptoms, and social participation could potentially serve as preventive measures against cognitive decline in elderly individuals afflicted with edentulism. This underscores the significance of addressing these factors to alleviate cognitive decline.

Association between tooth loss-related speech and psychosocial impairment with cognitive function: A pilot study in Hong Kong's older population

BACKGROUND

Tooth loss has been associated with cognitive decline, but the underlying mechanisms involving speech and psychosocial impairment remain unclear.

OBJECTIVES

To investigate the impact of tooth loss-related speech and psychosocial impairment on cognitive function in Hong Kong's older population.

METHODS

Seventy-six Cantonese-speaking participants between the ages of 51-92 were classified into three groups: patients with complete dentures (CD), partially edentulous patients with less than 10 occluding tooth pairs (OU <10), and at least 10 occluding tooth pairs (OU ≥10). Cognitive function was assessed using the Montreal Cognitive Assessment Hong Kong Version, One-minute Verbal Fluency Task and Hayling Sentence Completion Test. Objective and subjective speech assessments were carried out using artificial intelligence speech recognition algorithm and a self-designed speech questionnaire. The impact of tooth loss on psychosocial condition was evaluated by the Reading the Mind in the Eyes Test and a self-designed questionnaire. Statistical analyses (one-way ANOVA, ANCOVA, Kruskal-Wallis test, Spearman correlation test) were performed.

RESULTS

Tooth loss was significantly associated with lower cognitive function (p = .008), speech accuracy (p = .018) and verbal fluency (p = .001). Correlations were found between cognitive function and speech accuracy (p < .0001). No significant difference in tooth loss-related psychosocial impact was found between the three groups.

CONCLUSION

While warranting larger sample sizes, this pilot study highlights the need for further research on the role of speech in the association between tooth loss and cognitive function. The potential cognitive impact of tooth retention, together with its known biological and proprioceptive benefits, supports the preservation of the natural dentition.

Tooth loss impairs cognitive function in SAMP8 mice via the NLRP3/Caspase-1 pathway

OBJECTIVE

Loss of occlusal support due to tooth loss has been indicated as one of the risk factors for Alzheimer's disease. This study aimed to investigate the relationship between tooth loss and cognitive dysfunction and illustrate the role of neuroinflammation in advancing Alzheimer's disease.

MATERIALS AND METHODS

Male 5-month-old senescence-accelerated mouse strain P8 (SAMP8) mice were divided into three groups (n = 7): the C (control), S (sham-operated), and TL (tooth loss) groups. The Morris water maze (MWM) test was performed to assess spatial memory. Additionally, histopathological and molecular assessments of hippocampal tissues were performed.

RESULTS

The TL groups exhibited impaired spatial memory in the water maze. Tooth loss induced higher protein expression levels of the neuroinflammation cytokine interleukin-1β (IL-1β) in the hippocampus than in the S and C groups. Tooth loss activated the NLRP3 inflammasome and increased the expression of Caspase-1 in the hippocampus.

CONCLUSIONS

The findings indicated that tooth loss impairs cognitive function in SAMP8 mice and is closely related to the activation of NLRP3/Caspase-1 in the hippocampus.

Oral Microbially-Induced Small Extracellular Vesicles Cross the Blood-Brain Barrier

Porphyromonas gingivalis (Pg) and its gingipain proteases contribute to Alzheimer's disease (AD) pathogenesis through yet unclear mechanisms. Cellular secretion of small extracellular vesicles or exosomes (EXO) increases with aging as part of the senescence-associated secretory phenotype (SASP). We have shown that EXO isolated from Pg-infected dendritic cells contain gingipains and other Pg antigens and transmit senescence to bystander gingival cells, inducing alveolar bone loss in mice in vivo. Here, EXO were isolated from the gingiva of mice and humans with/without periodontitis (PD) to determine their ability to penetrate the blood-brain barrier (BBB) in vitro and in vivo. PD was induced by Pg oral gavage for 6 weeks in C57B6 mice. EXO isolated from the gingiva or brain of donor Pg-infected (PD EXO) or control animals (Con EXO) were characterized by NTA, Western blot, and TEM. Gingival PD EXO or Con EXO were labeled and injected into the gingiva of uninfected WT mouse model. EXO biodistribution in brains was tracked by an in vivo imaging system (IVIS) and confocal microscopy. The effect of human PD EXO on BBB integrity and permeability was examined using TEER and FITC dextran assays in a human in vitro 3D model of the BBB. Pg antigens (RGP and Mfa-1) were detected in EXO derived from gingival and brain tissues of donor Pg-infected mice. Orally injected PD EXO from donor mice penetrated the brains of recipient uninfected mice and colocalized with hippocampal microglial cells. IL-1β and IL-6 were expressed in human PD EXO and not in Con EXO. Human PD EXO promoted BBB permeability and penetrated the BBB in vitro. This is the first demonstration that microbial-induced EXO in the oral cavity can disseminate, cross the BBB, and may contribute to AD pathogenesis.

Do missing teeth cause early-onset cognitive impairment? Re-examining the evidence using a quasi-natural experiment

PURPOSE

Multiple studies have reported a positive association between missing teeth and cognitive impairment. While some authors have postulated causal mechanisms, existing designs preclude assessing this.

METHODS

We sought evidence of a causal effect of missing teeth on early-onset cognitive impairment in a natural experiment, using differential exposure to fluoridated water during critical childhood years (ages 5-20 years) in England as the instrument. We coded missing teeth from 0 (≤ 12 missing) to 3 (all missing) and measured the association with cognitive impairment in the English Longitudinal Study of Ageing data (2014-5), covering 4958 persons aged 50-70 years.

RESULTS

We first replicated previous evidence of the strongly positive association of missing teeth with cognitive impairment (β = 0.25 [0.11, 0.39]), after adjusting for socio-demographic covariates, such as age, gender, education, and wealth. Using an instrumental variable design, we found that childhood exposure to water fluoridation was strongly associated with fewer missing teeth, with being exposed to fluoridated water during childhood (16 years) associated with a 0.96 reduction in the missing teeth scale (β = - 0.06 [- 0.10, - 0.02]). However, when using the instrumented measure of missing teeth, predicted by probability of fluoride exposure, we found that missing teeth no longer had an association with cognitive impairment (β = 1.48 [- 1.22, 4.17]), suggesting that previous oral health-cognitive impairment associations had unobserved confounding.

CONCLUSIONS

Our findings are consistent with the possibility that unobserved confounding leads to the oft-observed association between missing teeth and early-onset cognitive impairment, suggesting that the relationship is spurious rather than causal.

Social participation, subjective well-being, and cognitive function as serial mediators between tooth loss and functional limitations in older Chinese adults

BACKGROUND

Although tooth loss appears to be related to functional limitations, the mechanisms that underpin this relationship are unknown. We sought to address this knowledge gap by examining a multiple mediation hypothesis whereby tooth loss is predicted to indirectly affect functional limitations through social participation, subjective well-being, and cognitive function.

METHODS

This study included 7,629 Chinese adults from the 2017/2018 Chinese Longitudinal Healthy Longevity Survey wave. The serial mediation effects were examined using Model 6 in the Hayes' PROCESS macro for SPSS.

RESULTS

Tooth loss was significantly related to functional limitations. There was a direct (β = - 0.0308; 95% CI, - 0.0131 to - 0.0036) and indirect (β = - 0.0068; 95% CI, - 0.0096 to - 0.0041) association between tooth loss and instrumental activities of daily living (IADL) limitations, but only an indirect correlation with activities of daily living (ADL) limitations (β = - 0.0188; 95% CI, - 0.0259 to - 0.0121). Social participation, subjective well-being, and cognitive function serially mediated the relationship between tooth loss and ADL/IADL limitations.

CONCLUSION

The association between tooth loss and functional limitations is serially mediated by social participation, subjective well-being, and cognitive function. Our findings underscore the necessity of considering psychological and social factors as integrated healthcare approaches for the functional health of older adults.

An umbrella review on the association between factors of oral health and cognitive dysfunction

An increasing number of systematic reviews and meta-analyses have been published on the association between oral health and cognitive dysfunction, also known as oral-cognitive links. However, there is great diversity in the oral and cognitive factors included in these studies, with different opinions for clinical practice drawn from the evidence. To understand which oral and cognitive factors are involved in those associations, we conducted an umbrella review of 28 systematic reviews, including 12 meta-analyses, on oral-cognitive links. We found that (a) periodontal diseases, oral microbiome, and dementia were frequently studied, while other factors, such as mastication and mild cognitive impairment, were less commonly investigated, and (b) severe deterioration of oral health, such as severe periodontitis or extensive tooth loss, rather than the presence of oral diseases alone, was strongly associated with cognitive dysfunction. In conclusion, the diversity of oral and cognitive factors included in the review studies reflects the complexity of oral-cognitive links. Clarifying the factors helps to form evidence-based clinical advice for healthcare.

White matter abnormalities mediate the association between masticatory dysfunction and cognition among older adults

BACKGROUND

Masticatory parameters, such as reduced number of teeth and posterior contacts, have been shown to be associated with reduced cognitive status. The underlying mechanisms that affect these associations, are however, not well understood.

OBJECTIVES

The study aims to investigate the association between masticatory dysfunction and cognition and explore the mediating effect of brain structure.

METHODS

In this cross-sectional study, 45 older adults with subjective masticatory dysfunction (mean age 72.3 ± 4.0 years) were included. Mini-Mental State Examination score <25, brain trauma, neurological disease, neurodegenerative disorders, depression or poor Swedish language skills were criteria for exclusion. Cognitive functions (executive function and episodic memory) and masticatory dysfunction defined by functional occluding status (FOS; the number of occluding units and number of remaining teeth) were analysed with partial correlation models. Structural magnetic resonance imaging was performed on 28 feasible participants. Multiple regression analyses were performed to evaluate the predictive value of brain structure and white matter hypointensities (WM-hypo) on cognitive functions. A mediation analysis was applied to assess significant predictor/s of the association between FOS and cognition.

RESULTS

Both episodic memory and executive functions were positively correlated with FOS. WM-hypo predicted cognitive status (executive function, p ≤ .01). WM-hypo mediated 66.6% (p = 0.06) of the association between FOS and executive functions.

CONCLUSION

Associations between FOS and cognitive functions are reported, where FOS, a potential modifiable risk factor, was related to both episodic memory and executive functions. The mediating effect of WM-hypo on the association between FOS and executive functions highlights the impact of the vascularisation of the brain on the link between mastication and cognition. The present study provides increased knowledge that bridges the gap between masticatory dysfunction and cognition.

Association between Dental Diseases and Oral Hygiene Care and the Risk of Dementia: A Retrospective Cohort Study

OBJECTIVES

To investigate the associations of dental diseases and oral hygiene care with the risk of dementia.

DESIGN

Retrospective longitudinal cohort study.

SETTING AND PARTICIPANTS

We conducted a population-based study of individuals in the Korean National Health Insurance System. A total of 2,555,618 participants who underwent cardiovascular and dental screenings in 2008 were included.

METHODS

Dental diseases including periodontal diseases, dental caries, and tooth loss were assessed by dentists. Information on oral hygiene care, including professional dental cleaning and the frequency of tooth brushing, was collected using a self-administered questionnaire. Study outcomes were all-cause dementia, Alzheimer's disease (AD), and vascular dementia (VaD).

RESULTS

Periodontal diseases [adjusted hazard ratio (aHR) 1.07, 95% CI 1.04-1.09], dental caries (aHR 1.03, 95% CI 1.00-1.05), and 8-14 missing teeth (aHR 1.07, 95% CI 1.02-1.12) were associated with an increased risk of all-cause dementia. In contrast, either professional dental cleaning or frequent tooth brushing were associated with decreased risks of all-cause dementia (aHR 0.91, 95% CI 0.89-0.93 each; aHR 0.83, 95% CI 0.80-0.86 for both). The increased risks by dental diseases were reduced by oral hygiene care: periodontal diseases with professional dental cleaning (aHR 0.94, 95% CI 0.91-0.98) or tooth brushing ≥2 times/day (aHR 0.97, 95% CI 0.94-1.00) and 1 to 7 missing teeth with professional dental cleaning (aHR 0.94, 95% CI 0.89-0.98) or tooth brushing ≥2 times/day (aHR 0.92, 95% CI 0.89-0.95). Consistent results were noted for AD and VaD and in various subgroup analyses.

CONCLUSION AND IMPLICATIONS

Periodontal disease, dental caries, and a high number of missing teeth were independently associated with a higher risk of dementia. Conversely, improved oral hygiene care, such as professional dental cleaning and frequent tooth brushing, may modify the risk of dementia associated with dental diseases.

A Survey of Oral Assessment and Healthcare Education at Nursing Schools in Japan

OBJECTIVES

This study aimed to investigate the performance of oral assessment and health care education at nursing schools across Japan to identify problems and the need for oral health professional support.

METHODS

The participants were the academic staff in charge of oral health care education in the basic, adult, gerontological, and home nursing fields of 295 schools in Japan that offered a bachelor's degree in nursing. A questionnaire was sent to 1180 heads of the nursing fields of these schools. They were requested to have oral health care educators complete the survey; data on the performance of oral assessment and health care education and human resources allocated were collected through a questionnaire.

RESULTS

A total of 311 (26%) questionnaires were returned, 196 (63%) of which were completed by oral health care educators. Regarding the performance of oral assessment education, the majority (71%) of them spent less than 2 hours in teaching, and only 24.5% taught the usage of oral assessment tools. Regarding the performance of oral health care education, more than 90% spent less than 2 hours in lecture-based and practical oral health care education, respectively. Less than half taught the association of periodontal diseases with diabetes and cardiovascular diseases and use of fluoride for caries prevention in the lectures, and only approximately 30% taught the usage of an interspace brush or dental floss. Moreover, less than 10% of oral health professionals taught oral health care in lectures or practical oral health care.

CONCLUSIONS

This study revealed problems associated with oral assessment and health care education in Japanese nursing schools. To address these, support from oral health care professionals is required. Further studies are also required to reveal problems in oral assessment and health care education in other nursing schools that do not offer a bachelor's degree programme in Japan and other countries.

Geroscience: Aging and Oral Health Research

Research in aging has significantly advanced; scientists are now able to identify interventions that slow the biologic aging processes (i.e., the "hallmarks of aging"), thus delaying the onset and progression of multiple diseases, including oral conditions. Presentations given during the 3-part session "Geroscience: Aging and Oral Health Research," held during the 2023 American Association for Dental, Oral, and Craniofacial Research meeting, are summarized in this publication. Speakers' topics spanned the translational research spectrum. Session 1 provided an overview of the geroscience and health span (disease-free and functional health throughout life) concepts. The common molecular mechanisms between oral cancer and aging were discussed, and research was presented that showed periodontal microflora as a potential factor in Alzheimer's disease progression. Session 2 focused on behavioral and social science aspects of aging and their oral health significance. The keynote provided evidence that loneliness and isolation can have major health effects. These social conditions, along with poor oral health, tooth loss, and cognitive decline, could potentially affect healthy eating ability and systemic health in older adults. Research could help elucidate the directions and pathways connecting these seemingly disparate conditions. Session 3 focused on the delivery of oral care in different settings and the many barriers to access care faced by older adults. Research is needed to identify and implement effective technology and strategies to improve access to dental care, including new delivery and financing mechanisms, workforce models, interprofessional provider education and practice, and use of big data from medical-dental integration of electronic health records. Research to improve the "oral health span," reduce oral health disparities, and increase health equity must be tackled at all levels from biologic pathways to social determinants of health and health policies.

Prediction Model Development and Validation of 12-Year Incident Edentulism of Older Adults in the United States

INTRODUCTION

Edentulism affects health and quality of life.

OBJECTIVES

Identify factors that predict older adults becoming edentulous over 12 y in the US Health and Retirement Study (HRS) by developing and validating a prediction model.

METHODS

The HRS includes data on a representative sample of US adults aged >50 y. Selection criteria included participants in 2006 and 2018 who answered, "Have you lost all of your upper and lower natural permanent teeth?" Persons who answered "no" in 2006 and "yes" in 2018 experienced incident edentulism. Excluding 2006 edentulous, the data set (n = 4,288) was split into selection (70%, n = 3,002) and test data (30%, n = 1,286), and Monte Carlo cross-validation was applied to 500 random partitions of the selection data into training (n = 1,716) and validation (n = 1,286) data sets. Fitted logistic models from the training data sets were applied to the validation data sets to obtain area under the curve (AUC) for 32 candidate models. Six variables were included in all models (age, race/ethnicity, gender, education, smoking, last dental visit) while all combinations of 5 variables (income, alcohol use, self-rated health, loneliness, cognitive status) were considered for inclusion. The best parsimonious model based on highest mean AUC was fitted to the selection data set to obtain a final prediction equation. It was applied to the test data to estimate AUC and 95% confidence interval using 1,000 bootstrap samples.

RESULTS

From 2006 to 2018, 9.7% of older adults became edentulous. The 2006 mean (SD) age was 66.7 (8.7) for newly edentulous and 66.3 (8.4) for dentate (P = 0.31). The baseline 6-variable model mean AUC was 0.740. The 7-variable model with cognition had AUC = 0.749 and test data AUC = 0.748 (95% confidence interval, 0.715-0.781), modestly improving prediction. Negligible improvement was gained from adding more variables.

CONCLUSION

Cognition information improved the 12-y prediction of becoming edentulous beyond the modifiable risk factors of smoking and dental care use, as well as nonmodifiable demographic factors.

KNOWLEDGE TRANSFER STATEMENT

This prediction modeling and validation study identifies cognition as well as modifiable (dental care use, smoking) and nonmodifiable factors (race, ethnicity, gender, age, education) associated with incident complete tooth loss in the United States. This information is useful for the public, dental care providers, and health policy makers in improving approaches to preventive care, oral and general health, and quality of life for older adults.

Associations of Dental Health With the Progression of Hippocampal Atrophy in Community-Dwelling Individuals: The Ohasama Study

BACKGROUND AND OBJECTIVES

Although tooth loss and periodontitis have been considered risk factors of Alzheimer disease, recent longitudinal researches have not found a significant association with hippocampal atrophy. Therefore, this study aimed to clarify a longitudinal association between the number of teeth present (NTP) and hippocampal atrophy dependent on the severity of periodontitis in a late middle-aged and older adult population.

METHODS

This study included community-dwelling individuals aged 55 years or older who had no cognitive decline and had undergone brain MRI and oral and systemic data collection twice at 4-year intervals. Hippocampal volumes were obtained from MRIs by automated region-of-interest analysis. The mean periodontal probing depth (PD) was used as a measure of periodontitis. Multiple regression analysis was performed with the annual symmetric percentage change (SPC) of the hippocampal volume as the dependent variable and including an interaction term between NTP and mean PD as the independent variable. The interaction details were examined using the Johnson-Neyman technique and simple slope analysis. The 3-way interaction of NTP, mean PD, and time on hippocampal volume was analyzed using a linear mixed-effects model, and the interaction of NTP and time was examined in subgroups divided by the median mean PD. In all models, dropout bias was adjusted by inverse probability weighting.

RESULTS

Data of 172 participants were analyzed. The qualitative interaction between NTP and the mean PD was significant for the annual SPC in the left hippocampus. The regression coefficient of the NTP on the annual SPC in the left hippocampus was positive (B = 0.038, p = 0.026) at the low-level mean PD (mean -1 SD) and negative (B = -0.054, p = 0.001) at the high-level mean PD (mean +1 SD). Similar results were obtained in the linear mixed-effects model; the interaction of NTP and time was significant in the higher mean PD group.

DISCUSSION

In a late middle-aged and older cohort, fewer teeth were associated with a faster rate of left hippocampal atrophy in patients with mild periodontitis, whereas having more teeth was associated with a faster rate of atrophy in those with severe periodontitis. The importance of keeping teeth healthy is suggested.

Association of tooth count with cognitive decline and dementia in the Finnish adult population

AIM

To evaluate whether tooth loss is associated with cognitive decline and incident dementia.

MATERIALS AND METHODS

We analysed data from the Finnish population-based Health 2000 and follow-up Health 2011 surveys (participants aged ≥30 years and without dementia at baseline; N = 5506 at baseline and 3426 at 11-year follow-up). Dementia diagnoses until 2015 were ascertained from national registers (N = 5542). Tooth count was dichotomized as adequate (≥20) versus tooth loss (<20). Tooth loss was further stratified into 10-19 teeth, 1-9 teeth and edentulism. Upper and lower jaws were also considered separately. Baseline cognitive test scores were dichotomized by median as high versus low, and 11-year change as decline versus no decline.

RESULTS

Tooth loss (<20) was associated with lower baseline overall cognition (odds ratio [OR] = 1.21, 95% confidence interval [CI] = 1.03-1.43), 11-year cognitive decline (OR = 1.30, 95% CI = 1.05-1.70) and higher 15-year dementia risk (hazard ratio = 1.52, 95% CI = 1.15-2.02) after adjusting for multiple confounders. After adjustment for dentures, associations became non-significant, except for 10-19 teeth remaining and dementia. Results were similar after considering reverse causality bias; however, 10-19 teeth remaining was significantly associated with 11-year cognitive decline even after adjustment for dentures. No jaw-specific differences were observed.

CONCLUSIONS

Tooth loss adversely impacts the risk of cognitive decline and dementia. The role of dentures should be further explored.

Association between oral hypofunction and general health: a systematic review

BACKGROUND

Oral hypofunction comprises 7 oral function conditions, including mastication, swallowing, pronouncing, oral hygiene, and oral dryness. However, it remains unresolved whether having oral hypofunction and each individual condition adversely affect general health. This study aimed to investigate the association between oral hypofunction and general health, encompassing physical, psychological, and social dimensions.

METHODS

Oral hypofunction was diagnosed following the criteria proposed by the 2016 Japan Society of Gerodontology, comprising 7 oral function conditions. Oral hypofunction was diagnosed when at least 3 conditions presented. The selected studies eligible for reviewing were based on the PI(E)CO criteria: P (population), adult and older adults; I/E (intervention/exposure), having oral hypofunction by considering overall and individual 7 oral function conditions; C (comparator), not having oral hypofunction; O (outcome), the general health status, encompassing physical, psychological, and social dimensions. Electronic search limited to English articles was performed through PubMed, Scopus, and Cochrane Database of Systematic Reviews databases from January 2016 to June 2023. The included studies were assessed for quaility and risk of bias using the modified Newcastle-Ottawa scale. Qualitative analyses were performed on the general outcome, and having oral hypofunction considering overall and individual oral function conditions.

RESULTS

Ten studies were included in the final syntheses. One was a prospective cohort, one was a case-control, and the others were cross-sectional studies. All included studies were high quality. General health outcomes were mostly frailty, sarcopenia, and malnutrition, whereas mild cognitive impairment,social withdrawal, and gastric cancer prognosis were identified in one of the included studies. The association between general health and having oral hypofunction was stronger than when considering an individual condition. The health outcomes were predominantly associated with mastication and swallowing, whereas their relationships with oral hygiene and dryness were less likely to be reported.

CONCLUSIONS

The present review found an association between the presence of oral hypofunction and impaired general health. However, the specific impact on individual physical, psychological, and social dimensions cannot be distinctly delineated. Further prospective studies are required to clarify the causal-effect relationship between oral and general health.

Oral health literacy, knowledge and perceptions in a socially and culturally diverse population: a mixed methods study

BACKGROUND

Poor oral health literacy has been proposed as a causal factor in disparities in oral health outcomes. This study aims to investigate oral health literacy (OHL) in a socially and culturally diverse population of Australian adults visiting a public dental clinic in Western Sydney.

METHODS

A mixed methods study where oral health literacy was assessed using the Health Literacy in Dentistry scale (HeLD-14) questionnaire and semi-structured interviews explored oral health related knowledge, perceptions and attitudes. Interviews were analysed using a thematic approach.

RESULTS

A sample of 48 participants attending a public dental clinic in Western Sydney was recruited, with a mean age of 59.9 (SD16.2) years, 48% female, 50% born in Australia, 45% with high school or lower education, and 56% with low-medium OHL. A subgroup of 21 participants with a mean age of 68.1 (SD14.6) years, 40% female, 64% born in Australia, 56% with a high school or lower education, and 45% with low-medium OHL completed the interview. Three themes identified from the interviews included 1) attitudes and perceptions about oral health that highlighted a lack of agency and low prioritisation of oral health, 2) limited knowledge and education about the causes and consequences of poor oral health, including limited access to oral health education and finally 3) barriers and enablers to maintaining good oral health, with financial barriers being the main contributor to low OHL.

CONCLUSIONS

Strategies aimed at redressing disparities in oral health status should include improving access to oral health information. The focus should be on the impact poor oral health has on general health with clear messages about prevention and treatment options in order to empower individuals to better manage their oral health.

Tooth Loss, Periodontal Disease, and Mild Cognitive Impairment Among Hispanic/Latino Immigrants: The Moderating Effects of Age at Immigration

BACKGROUND

The objectives were to assess (a) the association between poor oral health and mild cognitive impairment (MCI) in Hispanic/Latino immigrants and (b) potential modification effects on this association by age at immigration.

METHODS

Data were from the Hispanic Community Health Study/Study of Latinos and its ancillary study-the Study of Latinos-Investigation of Neurocognitive Aging. MCI, a binary outcome variable, defined by the National Institute on Aging-Alzheimer's Association criteria. The main exposure was significant tooth loss (STL), defined as a loss of 8 or more teeth, and periodontitis, classified using the Centers for Disease Control and Prevention and American Academy of Periodontology case classification. Multiple logistic regression was used to assess the association between STL/periodontitis and MCI and test moderation effects of age at immigration. The analytical sample comprised 5 709 Hispanic/Latino adult immigrants.

RESULTS

Hispanic/Latino immigrants with STL (adjusted odds ratio [AOR] = 1.36, 95% confidence interval [CI]: 1.01-1.85) were more likely to have MCI than those with greater tooth retention. Overall, migration to the United States after age 18 was associated with greater odds of MCI than migration at a younger age. A significant interaction effect between STL and age at immigration revealed that the effect of STL on MCI is even higher in those who immigrated to the United States at ages 35-49 years.

CONCLUSIONS

STL is a significant risk factor for MCI and age at immigration had a modification effect on the association between STL and MCI. Better access to dental care, health education on risk factors of MCI, and promotion of good oral health may mitigate the burden of cognitive impairment in Hispanics/Latinos.

[Association between oral health and cognitive decline in older Chileans]

OBJECTIVE

To identify the association between oral health and suspected cognitive impairment in older adults in Chile.

METHOD

Cross-sectional study including 1826 people ≥60 years who participated in the National Health Survey of Chile, 2016-2017. Oral health was evaluated by the number of teeth, presence of caries, use of dental prostheses, self-reported oral health, and pain and/or discomfort in the oral cavity. Cognitive impairment was assessed using the Mini-Mental State Examination (MMSE). The association was evaluated by logistic and linear regression, adjusted for sociodemographic and lifestyle variables.

RESULTS

Compared with people without suspicion of cognitive impairment, people with suspected impairment had five fewer teeth (13.4 vs. 8.5 teeth), a much higher difference in women than in men, and a higher frequency of oral pain. Edentulism and fewer teeth were associated with a higher likelihood of suspected cognitive impairment, associations that were not maintained in adjusted models. Oral pain was associated with a higher likelihood of suspected impairment even in the most adjusted model (odds ratio: 1.99; 95% confidence interval [95%CI]: 1.09-3.63). In linear models, an increase of 2% (95%CI: 0.01-0.05) in the MMSE score was observed for each additional tooth.

CONCLUSIONS

Poor oral health, particularly tooth loss and the presence of pain, was associated with cognitive impairment in older adults in Chile.

Food Hardness Modulates Behavior, Cognition, and Brain Activation: A Systematic Review of Animal and Human Studies

Food hardness is one of the dietary features that may impact brain functions. We performed a systematic review to evaluate the effect of food hardness (hard food versus soft food diet) on behavior, cognition, and brain activation in animals and humans (PROSPERO ID: CRD42021254204). The search was conducted on 29 June 2022 using Medline (Ovid), Embase, and Web of Science databases. Data were extracted, tabulated by food hardness as an intervention, and summarized by qualitative synthesis. The SYRCLE and JBI tools were used to assess the risk of bias (RoB) of individual studies. Of the 5427 studies identified, 18 animal studies and 6 human studies met the inclusion criteria and were included. The RoB assessment indicated that 61% of animal studies had unclear risks, 11% had moderate risks, and 28% had low risks. All human studies were deemed to have a low risk of bias. The majority (48%) of the animal studies showed that a hard food diet improved behavioral task performance compared to soft food diets (8%). However, 44% of studies also showed no differential effects of food hardness on behavioral tests. It was also evident that certain regions of the brain were activated in response to changes in food hardness in humans, with a positive association between chewing hard food, cognition performance, and brain function. However, variations in the methodologies of the included studies hindered the meta-analysis execution. In conclusion, our findings highlight the beneficial effects of dietary food hardness on behavior, cognition, and brain function in both animals and humans, however, this effect may depend on several factors that require further understanding of the causality.

Advances in tooth agenesis and tooth regeneration

The lack of treatment options for congenital (0.1%) and partial (10%) tooth anomalies highlights the need to develop innovative strategies. Over two decades of dedicated research have led to breakthroughs in the treatment of congenital and acquired tooth loss. We revealed that by inactivating USAG-1, congenital tooth agenesis can be successfully ameliorated during early tooth development and that the inactivation promotes late-stage tooth morphogenesis in double knockout mice. Furthermore, Anti- USAG-1 antibody treatment in mice is effective in tooth regeneration and can be a breakthrough in treating tooth anomalies in humans. With approximately 0.1% of the population suffering from congenital tooth agenesis and 10% of children worldwide suffering from partial tooth loss, early diagnosis will improve outcomes and the quality of life of patients. Understanding the role of pathogenic USAG-1 variants, their interacting gene partners, and their protein functions will help develop critical biomarkers. Advances in next-generation sequencing, mass spectrometry, and imaging technologies will assist in developing companion and predictive biomarkers to help identify patients who will benefit from tooth regeneration.

Time-varying exposure analysis of the relationship between sustained natural dentition and cognitive decline

AIM

Tooth loss and cognitive decline progress over time and influence each other. This study estimated the impact of sustaining natural dentition on cognitive function in U.S. adults, accounting for the fact that dental and cognitive statuses change over time.

MATERIALS AND METHODS

Data from adults aged ≥51 years who participated in five waves of the Health and Retirement Study from 2004 to 2016 (n = 10,953) were analysed. The impact of retaining some natural teeth from 2006 to 2012 on cognitive function score (0-27) and cognitive impairment (defined as having a cognitive function score of <12) in 2016 was evaluated using the doubly robust targeted maximum likelihood estimation method by considering both time-invariant and time-varying confounders, including cognitive function at baseline and during follow-up.

RESULTS

Respondents with some natural teeth between 2006 and 2012 had a 0.40 point (95% confidence interval [CI]: 0.10-0.71) higher cognitive function score and 3.27 percentage point (95% CI: 0.11-6.66) lower cognitive impairment prevalence in 2016 than those with complete tooth loss.

CONCLUSIONS

Considering past cognitive function assessed at multiple time points, sustained natural dentition was associated with better cognitive function.

Potential mechanisms between periodontitis and Alzheimer's disease: a scoping review

Background

Research has suggested 2 potential mechanisms by which the periodontal inflammatory response may communicate to distant organs: 1) direct translocation of periodontal bacteria from the oral cavity to another organ system; and 2) inflammation as a result of metastatic periodontal inflammation. The purpose of this scoping review is to explore these mechanisms as potential mediators between periodontitis and Alzheimer's disease.

Methods

A reiterative literature search of peer-reviewed articles was performed in the PubMed and Scopus databases using keywords or combinations such as Alzheimer's disease AND periodontitis OR periodontal disease AND inflammation.

Results

A total of 777 articles were identified. After eliminating duplicates and reviewing titles and abstracts, 84 articles were selected for full-text review. Following full-text review, 19 articles met the eligibility criteria for the study.

Discussion

The review of the literature highlights how periodontitis may contribute to neuroinflammation by the introduction of periodontal bacteria and/or proinflammatory cytokines locally produced at the periodontium.

Conclusion

Inflammation is an important mechanism in the onset and progression of both periodontitis and Alzheimer's disease. Nevertheless, further studies are necessary to better understand the multifactorial pathogenesis of Alzheimer's disease.

Adverse Childhood Experiences and Oral Health Conditions Among Middle-aged and Older Chinese Adults: Exploring the Moderating Roles of Education and Gender

This study aims to examine whether adverse childhood experiences (ACEs) are associated with oral health conditions (denture use, difficulty in chewing, and edentulism) among middle-aged and older adults in China and if gender and adulthood education moderate the associations. Data were obtained from the 2014 and 2018 surveys from the China Health and Retirement Longitudinal Study (N = 17,091) and logistic regressions were carried out. Results show that childhood hunger (OR = 1.12), loneliness (OR = 1.10) and family relations (OR = 1.07) were significantly associated with higher odds of denture use and there were significant associations between hunger (OR = 1.16) and difficulty in chewing. For the female subsample, education significantly moderated the adverse effect of childhood hunger on denture use and difficulty in chewing. Findings suggest that ACEs have long-lasting impacts on oral health conditions in later life and adulthood education might offer critical resources for females, helping them buffer the detrimental health impacts of ACEs.

New horizons in understanding oral health and swallowing function within the context of frailty

Frailty is a complex and multidimensional condition wherein declines in physiologic reserve and function place individuals in a state of heightened vulnerability and decreased resiliency. There has been growing interest in both research and clinical settings to understand how to best define, assess and characterise frailty in older adults. To this end, various models and clinical assessment tools have been used to define and measure frailty. While differences exist among these models and tools, a common unifying theme is a focus on physical function and activity. Notably absent across many available conceptual models and clinical tools are items directly related to oral and swallowing function. This is an important oversight as widespread changes to both oral and swallowing function are evident in older adults. Indeed, emerging evidence suggests many of the functional domains affected in frail older adults, such as nutrition and sarcopenia, have cyclical relationships with impairments in oral (oral hypofunction) and swallowing function (dysphagia) as well. The increasing appreciation for the interrelationships among oral hypofunction, dysphagia and frailty provides an opportunity for refinement of frailty assessment and characterisation in older adults to incorporate metrics specific to oral and swallowing function.

Poor Oral Health as a Risk Factor for Dementia in a Swedish Population: A Cohort Study with 40 Years of Follow-Up

BACKGROUND

Whether poor oral health is associated with dementia risk remains unclear.

OBJECTIVE

We conducted a cohort study of 14,439 participants who were followed up for up to 40 years in Uppsala County, central Sweden, aiming to explore the association between poor oral health, namely the number of tooth loss, dental plaque status, and oral mucosal lesions, and the risk of dementia.

METHODS

We used Cox proportional hazards regression model to derive cause-specific hazard ratios (HR) and corresponding 95% confidence intervals (CI), while adjusting for baseline potential confounders as well as a time-varying covariate, Charlson's Comorbidity Index score.

RESULTS

Dementia risk was substantially higher among those with a higher number of tooth loss; compared to the group with tooth loss 0-10, the HRs were 1.21 (95% CI: 1.02, 1.42), 1.17 (95% CI: 0.97, 1.40), and 1.30 (95% CI: 1.09, 1.54) respectively for groups with increasing number of tooth loss. There was some evidence of dose-risk association in this study, with a HR of 1.10 (1.04, 1.18) comparing adjacent groups (ptrend = 0.001). In a stratified analysis by attained age, tooth loss was more pronouncedly associated with the risk of dementia onset before age 80 (those with 21-32 versus 0-10 lost teeth, HR = 1.82, (95% CI: 1.32, 2.51); HR = 1.22 (95% CI: 1.10, 1.35) comparing adjacent groups, ptrend < 0.001).

CONCLUSION

In summary, there are some indications that poor oral health, as indicated by more tooth loss, is positively associated with an increased risk of dementia, especially for dementia onset before age 80.

Weight Loss Mediated the Relationship between Tooth Loss and Mortality Risk

Tooth loss is a risk factor for increased mortality; however, the underlying mechanism remains unclear. This study aimed to evaluate the mediating effect of weight change on the relationship between tooth loss and mortality risk. This was a 10-y follow-up prospective cohort study using the data from the Japan Gerontological Evaluation Study (JAGES). The participants were independent older adults aged ≥65 y at baseline and were followed up from 2010 to 2020. The incidence of death in 2013 and 2020, incidence of >5% weight loss/gain in 2010 and 2013, and the number of remaining teeth in 2010 were used as the outcome, mediator, and explanatory variables, respectively. We conducted causal mediation analysis by fitting the Cox proportional hazard model, including possible confounders. Hazard ratios (HRs) and 95% confidence intervals (95% CIs) of the total effect (TE), natural indirect effect (NIE), and proportion mediated (PM) were estimated. Among the 34,510 participants, the mean age was 72.6 (SD = 5.4) y, and 47.6% were men. From 2013 to 2020, 14.0% of the participants (n = 4,825) died, 60.5% (n = 20,871) had 0 to 19 remaining teeth, and 17.2% (n = 5,927) and 8.4% (n = 2,907) experienced >5% weight loss and gain, respectively. The mortality rate was 0.016 per person-year among those with ≥20 remaining teeth and 0.027 per person-year among those with 0 to 19 remaining teeth. Weight loss of >5% significantly mediated the association between tooth loss and higher mortality risk (TE: HR, 1.28 [95% CI, 1.16 to 1.40]; NIE: HR, 1.03 [95% CI, 1.02 to 1.04]; PM, 13.1%); however, we observed a slight mediating effect for >5% weight gain (NIE: HR, 1.003 [95%CI, 1.0001 to 1.01]; PM, 1.3%). The present study suggests that a clinically meaningful level of weight loss mediated the association between tooth loss and increased risk of mortality among independent older adults.

Unhealthy oral status contributes to the older patients with cognitive frailty: an analysis based on a 5-year database

BACKGROUND

Oral health is associated with the onset and deterioration of cognitive function and physical frailty, which can be improved with appropriate interventions. However, far too little attention has been paid to oral health status of elderly with cognitive frailty. The objective of this study was to investigate the oral health status and potential risk factors of elderly hospitalized patients aged 60 years or older with cognitive frailty.

METHODS

The participants' assessment data derived from the Comprehensive Geriatric Assessment Database of hospitalized patients from The First Affiliated Hospital of Chongqing Medical University. Data were collected from April 2016 to December 2021. All participants underwent a face-to-face assessment conducted by professional evaluators. Physical frailty was defined by Fried's criteria. Cognitive function was assessed by Mini Mental State Examination (MMSE). The cognitive frailty is characterized by the simultaneous presence of at least 1 Fried's criteria and mild cognitive impairment according to Diagnostic and Statistical Manual of Mental Disorders 5th edition. The oral health was assessed according to 10-item Brief Oral Health Status Examination (BOHSE). The general demographic characteristics, BOHSE scores were compared between the cognitive frailty and non-cognitive frailty (control group). The score of BOHSE and ten items were included in the binary logistic regression analysis. The covariate characteristics were adjusted for a final model with a multivariate analysis.

RESULTS

A total of 425 patients (245 females) with cognitive frailty and 491 patients (283 females) with non-cognitive frailty were enrolled in this retrospective study. Univariate analysis showed statistically significant differences in age, education level, living arrangement, diabetes, Body Mass Index (BMI), Pittsburgh Sleep Quality Index (PSQI), depression between the two groups. The total BOHSE score of cognitive frailty was higher than that of the control group (4.35 ± 2.68 vs. 3.64 ± 2.60, Z = 4.07, P < 0.001). The average scores and the proportions of health changes and unhealthy states of tongue, mucosa tissue, gums, natural teeth, dentures, masticatory teeth and oral hygiene in cognitive frailty were greater than those of the control group (all P < 0.05). The binary logistical regression analysis showed that four or more natural teeth decayed or broken was independently associated with cognitive frailty after adjusting the age, gender, education level, living arrangement and BMI, PSQI, diabetes and depression (OR = 1.91, 95%CI: 1.20-3.07, P = 0.007). Additionally, while in the chewing position, those cases with a normal-occlusal-relationship number of less than 11 pairs had a higher risk of cognitive frailty than those with 12 pairs or more.

CONCLUSIONS

The oral health status of older hospitalized patients over 60 years with cognitive frailty was worse than that of patients with non-cognitive frailty. But only four or more natural teeth decayed or broken and a reduction in chewing pairs were independent risk factors for cognitive frailty.

Differences in Brain Volume by Tooth Loss and Cognitive Function in Older Japanese Adults

BACKGROUND

We investigated the association between tooth loss and structural brain volume and its mediating effect on the association between tooth loss and cognitive function in older Japanese.

METHODS

A cross-sectional study was conducted by using the data of 494 randomly sampled community-dwelling individuals aged 65-84 years living in Tokamachi City, Japan. Total brain volume (TBV), gray matter volume (GMV), white matter volume (WMV), and hippocampal volume (HV) were measured with magnetic resonance imaging. The association of self-reported number of teeth (≥20, 1-19, and 0) with cognitive function assessed with the Japanese version of the Quick Mild Cognitive Impairment screen and structural brain volume was examined. Causal mediation analysis was performed to evaluate the mediating effect of structural brain volume. Age, sex, socioeconomic status, health behavior, comorbid conditions, and total intracranial volume were adjusted.

RESULTS

Respondents with no teeth showed lower cognitive function (coefficient = -4.01; 95% confidence interval [CI]: -7.19, -0.82), lower TBV (coefficient = -10.34; 95% CI: -22.84, 2.17), and lower GMV (coefficient = -6.92; 95% CI: -14.84, 0.99) than those with ≥20 teeth (P for trends were 0.003, 0.035, and 0.047, respectively). The number of teeth was not significantly associated with WMV or HV. GMV showed a significant mediating effect on the association between the number of teeth and cognitive function (coefficient = -0.38; 95% CI: -1.14, -0.002, corresponding to 9.0% of the total effect), whereas TBV did not.

CONCLUSIONS

GMV was suggested to mediate the relationship between tooth loss and lower cognitive function.

Current status and future prospects for oral care education in Bachelor of Nursing curriculums: A Japanese cross‐sectional study

OBJECTIVE

This study sought to investigate the current status and faculty members' perceptions of oral care education in Bachelor of Nursing curriculums in Japan.

METHOD

Data were gathered through a questionnaire survey of 196 participants, who were faculty members in charge of oral care education in the basic, adult, gerontological, and home nursing fields, from 295 nursing schools that offered Bachelor degrees in nursing across Japan.

RESULTS

The quantitative data showed that 38.5% of the participants worked for less than 5 years as oral care educators, only 15.5% taught oral care in perioperative wards, only 62.2% used an oral care training simulator, and less than 30% believed that training in the prevention of oral diseases should be enhanced. From the descriptive responses, this study identified such problems as the inability of students to perform student-on-student and patient-based oral care training owing to the risk of SARS-CoV-2 transmission, and the lack of teaching materials, time, and human resources, and cooperation with other nursing fields and health professionals.

CONCLUSIONS

This study revealed several problems in oral care education in the Bachelor of Nursing curriculums in Japan. To tackle these challenges, this study suggests the development of an interdisciplinary course that unifies oral care education in nursing fields, in order to promote collaborative oral care education and to improve nursing students' knowledge and skills of oral care.

COR388 (atuzaginstat): an investigational gingipain inhibitor for the treatment of Alzheimer disease

INTRODUCTION

Evidence from in vitro and in vivo studies demonstrates that amyloid beta (Aβ) oligomers have potent, broad-spectrum antimicrobial properties created by fibrils that entrap pathogens and disrupt their membranes. Data suggest that Aβ may play a protective role in the innate immune response to microbial infections and that Aβ in the brain plays a damaging role when the inflammatory response is not well controlled.

AREAS COVERED

This paper describes the relationship between periodontal disease and Alzheimer disease (AD), the role of Porphyromonas gingivalis and its secreted gingipains in AD, and the potential of the gingipain inhibitor atuzaginstat (COR388) to modulate AD neuropathologies.

EXPERT OPINION

P. gingivalis is opsonized by Aβ42, is capable of entering the brain, and is an accelerant of neuropathologies in rodent models of AD. Thus, in our opinion, this bacteria is highly likely to be a pathogen capable of initiating or precipitating the progression of AD, which agrees with the pathogen hypothesis of clinical AD development.

Periodontal health, cognitive decline, and dementia: A systematic review and meta-analysis of longitudinal studies

BACKGROUND

Emerging evidence indicates that poor periodontal health adversely impacts cognition. This review examined the available longitudinal evidence concerning the effect of poor periodontal health on cognitive decline and dementia.

METHODS

Comprehensive literature search was conducted on five electronic databases for relevant studies published until April 2022. Longitudinal studies having periodontal health as exposure and cognitive decline and/or dementia as outcomes were considered. Random effects pooled estimates and 95% confidence intervals were generated (pooled odds ratio for cognitive decline and hazards ratio for dementia) to assess whether poor periodontal health increases the risk of cognitive decline and dementia. Heterogeneity between studies was estimated by I2 and the quality of available evidence was assessed through quality assessment criteria.

RESULTS

Adopted search strategy produced 2132 studies for cognitive decline and 2023 for dementia, from which 47 studies (24 for cognitive decline and 23 for dementia) were included in this review. Poor periodontal health (reflected by having periodontitis, tooth loss, deep periodontal pockets, or alveolar bone loss) was associated with both cognitive decline (OR = 1.23; 1.05-1.44) and dementia (HR = 1.21; 1.07-1.38). Further analysis, based on measures of periodontal assessment, found tooth loss to independently increase the risk of both cognitive decline (OR = 1.23; 1.09-1.39) and dementia (HR = 1.13; 1.04-1.23). Stratified analysis based on the extent of tooth loss indicated partial tooth loss to be important for cognitive decline (OR = 1.50; 1.02-2.23) and complete tooth loss for dementia (HR = 1.23; 1.05-1.45). However, the overall quality of evidence was low, and associations were at least partly due to reverse causality.

CONCLUSIONS

Poor periodontal health and tooth loss appear to increase the risk of both cognitive decline and dementia. However, the available evidence is limited (e.g., highly heterogenous, lacking robust methodology) to draw firm conclusions. Further well-designed studies involving standardized periodontal and cognitive health assessment and addressing reverse causality are highly warranted.

Association between dentition and frailty and cognitive function in community-dwelling older adults

Objectives

To evaluate dentition status amongst community-dwelling older adults and its association with frailty and cognitive impairment.

Methodology

One thousand forty-seven community-dwelling older adults aged ≥65 years were surveyed in an epidemiologic population-based cohort study in Singapore between April 2015 and August 2016. Data on demographics, dentition status, chronic diseases, activities and instrumental activities on daily-living, cognition (age- and education-specific MMSE cut-offs), frailty (FRAIL scale), perceived health and functional status were collected. Multiple logistic regression was performed to examine the association between dentition, frailty and cognition.

Results

Mean age of participants was 71.2 ± 5.5 years. The prevalence of denture use was 70.7% and edentulism 7.9%. Compared to edentulousness, having teeth was associated with lower odds of cognitive impairment and higher odds of being robust or pre-frail. Denture-wearers compared with edentulous persons were less likely to be male, had higher education level and more likely be robust or pre-frail.

Conclusion and implications

There were significant associations between dentition status, frailty and cognition in our study where those with remining teeth and / or dentures had better overall outcomes. As oral health, frailty and cognitive impairments are all modifiable risk factors for healthy ageing, countries should consider population level screening for oral health, frailty and cognitive impairment.

Is the Number of Missing Teeth Associated With Mortality? A Longitudinal Study Using a National Health Screening Cohort

This study aimed to estimate the risk of mortality related to the number of missing teeth in a South Korean population. The ≥ 40-year-old population of the Korean National Health Insurance Service-Health Screening Cohort 2002–2003 was analyzed. Participants were selected from a total of 220,189 participants and included in groups of 0 teeth lost, 1–2 teeth lost, and ≥ 3 teeth lost. Among the total population, 17,211 participants were included in no missing teeth, 1–2 missing teeth, and ≥ 3 missing teeth and were randomly matched 1:1:1 for age and sex. Mortality from specific causes and all-cause mortality were compared among the groups. The hazard ratio (HR) of the number of missing teeth for all-cause mortality or each cause of mortality was analyzed using Cox proportional hazard models. According to the cause of death, the HRs for metabolic disease, digestive disease, and trauma were greater in the group with ≥ 3 missing teeth than in the no missing teeth group. The group with ≥ 3 missing teeth indicated a 1.19-fold higher HR for all-cause mortality than the no missing teeth group [95% confidence intervals (95% CIs) = 1.12–1.27, P &lt; 0.001]. The group with 1- 2 missing teeth did not show a higher HR for all-cause mortality. In the group with 1–2 missing teeth, the HRs for mortality from mental disease and digestive disease were higher than those in the no missing teeth group. The group with 1–2 missing teeth did not show a higher HR for all-cause mortality. The number of missing teeth was linked with a higher risk of mortality. For specific causes of mortality, mortality from metabolic disease, digestive disease, and trauma was higher in the participants with the number of missing teeth.

Oral Health-Related Quality of Life and Missing Teeth in an Adult Population: A Cross-Sectional Study from Poland

The aim of the study was to determine oral health–related quality of life (OHRQoL) using the measures Geriatric/General Oral Health Assessment (GOHAI) and Oral Health Impact Profile (OHIP-14) in relation to missing teeth in the Polish population aged 20–79. This was a cross-sectional study carried out among 1112 randomly selected participants. The mean age was 48.72 and mean number of teeth was 20.12. Altogether, in the GOHAI, the percentage that gave a positive response to each question ranged from 3.3% to 48.0%; in the OHIP-14, these answers ranged from 2.4% to 25.1%. The GOHAI measure was statistically significant, with more grouping variables than the OHIP-14 measure. Both measures showed significant associations with gender, age, dry mouth, education, professional status, number of teeth, and upper and lower total dentures. We detected a significant relationship between oral health–related quality of life and the factors influencing the presence or absence of dentition. Missing teeth were statistically associated with GOHAI, OHIP-14, advanced age, self-reported dry mouth, lower education, higher Body Mass Index (BMI), lower professional status, diabetes, myocardial infraction, and total dentures in upper or/and lower jaws. However, edentulous individuals had two times higher risk of having an OHIP-14 score above the median. This suggests that oral health practitioners should work to prevent oral diseases that lead to tooth loss in their patients, starting from an early age.

The Association between Number of Teeth and Cognitive Frailty in Older Adults: A Cross-Sectional Study

OBJECTIVES

This study aimed to explore the association between number of teeth and cognitive frailty in American older adults.

DESIGN

Cross-sectional study.

SETTING

Community.

PARTICIPANTS

The participants were 1,531 community-dwelling older adults aged 60 or older from the NHANES database.

METHODS

Frailty was assessed using a 49-item frailty index, with a cut-off value for frailty of more than 0.21. Cognitive dysfunction was evaluated by the Digit-Symbol Coding Test (DSCT), with the cut-off being below the lowest interquartile range (scores ≤37). Cognitive frailty was defined as participants who suffered from both frailty and cognitive dysfunction. Oral health indicators included number of teeth and other factors, such as the presence of gum disease, daily use of dental floss, daily use of mouthwash and self-rated oral health. Multivariable logistic regression models were used to explore the relationship between number of teeth and cognitive frailty.

RESULTS

The mean age of the total sample was 69.67 (SD=6.60) years, and 52.71% (n=807) were female. Our study suggests there was a negative association between number of teeth and cognitive frailty (OR =0.98,95%CI:0.96-0.99, P=0.044) after controlling for potential confounding factors. In addition, older adults with 20 or more teeth had lower odds of being cognitively frail (OR=0.66,95%CI:0.44-0.99, P=0.046) than individuals who had less than 20 teeth.

CONCLUSION

This study suggests that older adults who have more teeth are associated with a lower risk of cognitive frailty. This finding highlights the importance of maintaining as many teeth as possible throughout life and into old age. Cohort studies will be required in the future to determine this relationship.