Effects of self-assessed chewing ability, tooth loss and serum albumin on mortality in 80-year-old individuals: a 20-year follow-up study

Implication of serum and salivary albumin tests in the recent oral health related epidemiological studies: A narrative review

Albumin is the most abundant protein in human serum and a specific amount of albumin also can be found in the saliva. It has several physiological functions such as blood colloidal osmotic pressure, antioxidant activity, binding and transporting of endogenous and exogenous substrates. We conducted an electronic search across several databases such as PubMed, Scopus, Cochrane, Embase and Science Direct using the relevant MeSH terms and keywords like "albumin", "serum albumin", "salivary albumin", "oral health" "dental caries" and "epidemiology". Only the epidemiological studies published between 2010 and 2023 were included. After the application of the inclusion criteria, a total of 51 studied were included in this narrative review. Serum and salivary albumin tests have been used in various aspects of oral health as a diagnostic and prognostic factor. Some of the results point out to a pattern of association while some of them are inconclusive and even contradictory. This narrative review discusses the role, significance and impact of albumin in epidemiological oral health related studies including the categories of periodontal health and disease, dental caries, oral function and hypofunction, nutrition and malnutrition, tooth loss and its treatment, diabetes and cancer. In addition, it offers a short manual for the researchers on when, where and how to use albumin tests in planning their study designs whether investigating an association or measure them as a covariate.

Oral Function and the Oral Microbiome in the Elderly in the Kyotango Area

INTRODUCTION

Prevention of tooth loss contributes to an extended life expectancy, namely longevity. Aging-related oral hypofunction, including tooth loss, markedly increases the risks of functional disorder and mortality. Dysbiosis of the oral microbiome has recently been associated with various diseases, such as liver cirrhosis, pancreatic cancer, colorectal cancer, and inflammatory bowel disease. Therefore, the relationship between the oral microbiome and systemic health has been attracting increasing attention. In the present study, we examined oral function and the oral microbiome in the elderly in a world-leading longevity area.

MATERIALS AND METHODS

An oral examination, chewing ability/tongue-lip motor function/saliva tests, and a metagenomic analysis with a 16S rRNA gene-targeting next-generation sequencer were conducted on 78 subjects aged ≥80 years. Twenty-six healthy individuals aged between 20 and 39 years were also investigated as controls. The data obtained were statistically analyzed. The protocol of the present study was approved by the Ethics Review Board of our university (ERB-C-885).

RESULTS

Chewing ability, tongue-lip motor function, and saliva volume were normal in elderly subjects with a current tooth number ≥20, but were significantly lower in those with a current tooth number <20. The oral microbiome in elderly subjects with a current tooth number ≥20 and young controls differed from that in elderly subjects with a current tooth number <20.

CONCLUSION

Tooth number ≥20 in elderly subjects in the longevity area contributed to the maintenance of both oral function and the diversity of the oral microbiome.

The rosetta stone of successful ageing: does oral health have a role?

Ageing is an inevitable aspect of life and thus successful ageing is an important focus of recent scientific efforts. The biological process of ageing is mediated through the interaction of genes with environmental factors, increasing the body's susceptibility to insults. Elucidating this process will increase our ability to prevent and treat age-related disease and consequently extend life expectancy. Notably, centenarians offer a unique perspective on the phenomenon of ageing. Current research highlights several age-associated alterations on the genetic, epigenetic and proteomic level. Consequently, nutrient sensing and mitochondrial function are altered, resulting in inflammation and exhaustion of regenerative ability.Oral health, an important contributor to overall health, remains underexplored in the context of extreme longevity. Good masticatory function ensures sufficient nutrient uptake, reducing morbidity and mortality in old age. The relationship between periodontal disease and systemic inflammatory pathologies is well established. Diabetes, rheumatoid arthritis and cardiovascular disease are among the most significant disease burdens influenced by inflammatory oral health conditions. Evidence suggests that the interaction is bi-directional, impacting progression, severity and mortality. Current models of ageing and longevity neglect an important factor in overall health and well-being, a gap that this review intends to illustrate and inspire avenues for future research.

Efficacy and risk factors of traditional denture restoration versus biofunctional complete denture restoration system

OBJECTIVE

This study was designed to determine the efficacy of a traditional complete denture and a biofunctional prosthetic system of a complete denture, and risk factors affecting their efficacy.

METHODS

A retrospective analysis was performed on 95 patients with total dentition loss admitted to our hospital from January 2015 to June 2022. Among them, 45 patients who received traditional dentures were assigned to a control group, and the other 50 who received a biofunctional prosthetic system with complete dentures were assigned to an observation group. The clinical efficacy was compared between the two groups before and after treatment, and the masticatory function indexes and comfort scores of the two groups were also compared. Logistics regression analysis was conducted to analyze the risk factors affecting the efficacy of patients.

RESULTS

The observation group showed a higher total effective rate than the control group (P<0.05). After treatment, the observation group showed notably higher masticatory efficiency and absorbance of masticatory substances than the control group (P<0.05). In addition, the denture tenderness point in the observation group was notably lower than that in the control group (P<0.05). After treatment, the observation group had notably higher scores in General Comfort Questionnaire than the control group (P<0.05). Moreover, according to Logistics regression analysis, older age, dentition loss caused by tooth defect, smoking history and traditional denture restoration were independent risk factors for ineffective treatment.

CONCLUSION

The biofunctional prosthetic system of complete dentures can better improve the masticatory function and enhance the comfort of patients with total dentition loss, and with good efficacy.

Reduced Number of Remaining or Healthy Teeth in Patients with Type 2 Diabetes Mellitus: A Cross-sectional Study Assessed by Dentists or Dental Hygienists in Japan

Objective This study assessed the relationships between oral health (number of remaining and healthy teeth and periodontal disease) and type 2 diabetes mellitus (T2DM) to contribute to improved patient care. Patients We conducted a cross-sectional cohort study of consecutive patients being regularly treated for chronic diseases (T2DM, hypertension, and dyslipidemia). A dentist or dental hygienist accurately evaluated the oral environment. Patients with fewer than 20 teeth were classified as having reduced remaining teeth (RRT). Results A total of 267 patients were enrolled, including 153 patients (57%) with T2DM and 114 without (43%). Patients with T2DM had 3 fewer remaining teeth on average than those without DM [median: 22 (interquartile range (IQR): 11-27) vs. median: 25 (IQR: 17.3-28), p=0.02]. In addition, patients with T2DM had 4 fewer healthy teeth on average than those without DM [median: 8 (IQR: 2.8-15) vs. median: 12 (IQR: 6-16), p=0.02]. The frequency of RRT was higher in the T2DM group (n=63; 41%) than in the non-DM group (n=31; 27%, p=0.02). Multivariable logistic regression for the presence of RRT in the T2DM group found that age [odds ratio (OR), 1.08; 95% confidence interval (CI), 1.03-1.13; p<0.01] and regular dental consultations (OR, 0.28; 95% CI, 0.10-0.76; p=0.01) were independently and significantly associated. Conclusion The number of remaining or healthy teeth was significantly lower in patients with T2DM than in those without T2DM in current Japanese clinical practice. Regular dental consultation is recommended to preserve remaining teeth in patients with T2DM.

Relationship between maintenance of occlusal support achieved by home-visit dental treatment and prognosis in home-care patients-a preliminary study

AIM

To determine whether occlusal maintenance and reconstruction by dental intervention is associated with the prognosis of older home-care patients.

METHODS

The study participants were 289 older home-care patients (101 males, mean age 82.2 ± 7.7 years) who received visiting dental treatment from dental clinics in the region between 2012 and 2018. The participants were followed up for 1000 days after receiving the necessary dental treatment in a home-visit setting. The participants were divided into three groups: those with natural tooth occlusion, those whose molar occlusion was maintained or reconstructed by dentures, and those whose occlusion was not reconstructed. Factors associated with prognosis were determined using the Cox proportional hazard model, with occlusal status, comorbidities, the activity of daily living, and residence status as explanatory variables.

RESULTS

In the overall population, occlusal status (hazard ratio [HR] of those with occlusal disintegration versus those with natural tooth occlusion: 2.1, confidence interval [95% CI]: 1.18-3.82) and age (HR: 2.28, 95% CI: 1.44-3.61) were identified as significant factors. In the group of participants aged <85 years, only occlusal status (HR of those with occlusal disintegration versus those with natural tooth occlusion: 3.4, 95% CI: 1.34-8.68) was a significant factor. In the group of participants aged ≥85 years, occlusal status was not significantly associated with prognosis.

CONCLUSIONS

The maintenance and acquisition of occlusal support achieved by dental treatment contribute to improved prognosis in older patients younger than 85 years requiring home nursing care. Geriatr Gerontol Int 2022; 22: 976-981.

Association between dietary hardness score and activities of daily living among individuals aged 90 years

Objectives

With the rapidly aging world population, Japan has many older people with difficulties in maintaining oral health. This study aimed to investigate the relationship between dietary hardness score and performance of activities of daily living (ADL) of 90‐year‐old individuals in rural areas of Japan.

Material and Methods

A total of 236 individuals (64 men and 172 women) aged 90 years in Mitsugi town, Hiroshima, Japan, were included. Assessment of oral status and survey of ADL were performed. The association of ADL with dietary hardness score and the number of remaining teeth was determined.

Results

The mean dietary hardness score was 8.3 ± 2.6. Eighty individuals showed independence in ADL, whereas 156 individuals showed dependence. Logistic regression analysis, adjusted for potential confounding factors, showed that dietary hardness score was associated with ADL status but not the number of remaining teeth.

Conclusion

Our findings suggest that a low dietary hardness score is associated with dependence on ADL in 90‐year‐old individuals.

Association between oral health and frailty: results from the Korea National Health and Nutrition Examination Survey

Background

Previous research has suggested that poor oral health is positively associated with frailty. The objective of this study was to explore associations of key oral diseases (periodontal disease, tooth loss), and oral hygiene and management behaviors with the level of frailty in community-dwelling older Korean adults using national representative survey data.

Methods

This study used cross-sectional, 6th and 7th Korea National Health and Nutrition Examination Survey (KNHANES VI, VII) data. Adults aged 50+ years were included. Frailty was measured using frailty phenotype (FP) and frailty index (FI). FP was determined using five frailty criteria, i.e., weight loss, weakness, exhaustion, slowness, or low physical activity, and the level of frailty was classified with the number of criteria present (robust, none; pre-frail, 1–2; frail, 3+). FI was determined using a 44-item FI constructed according to a standard protocol, and the level of frailty was classified as robust (FI: ≤ 0.08), pre-frail (FI: 0.08–0.25), and frail (FI: ≥ 0.25). Multiple ordinal regression analyses were conducted with each type of frailty as the outcome variable. Independent variables of interest were the periodontal status, number of teeth, and practices on oral hygiene and management. Analyses were additionally adjusted for participants’ socioeconomic, diet, and behavioral characteristics.

Results

The prevalence of frailty was 4.38% according to the FP classification (n = 4156), 10.74% according to the FI classification (n = 15,073). In the final adjusted model, having more teeth and brushing after all three meals were significantly associated with lower odds of being more frail (in both frailty models); no significant association was observed between periodontal disease and frailty.

Conclusions

Findings from this study show having more teeth and practicing adequate brushing are significantly associated with frailty. Due to limitations of the study design, well-designed longitudinal studies are needed to confirm these findings.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-022-02968-x.

Food for the elderly based on sensory perception: A review

Background

The impairments of physiological functions caused by aging are common problems in the elderly, especially the impairments of sensory perception. Besides, close relationship between food sensory perception and nutritional status also suggests the importance of dietary management for the elderly population. The foods taking sensory perception into account are urgently needed by the elderly.

Scope and approach

This review analyzed sensory perception changes and their effects on food behaviors and nutritional status. Besides, sensory properties essential for aged-foods and acquisition methods, as well as current status of such foods were summarized.

Key findings and conclusions

Soft, smooth and moisty foods were more suitable for the elderly with chewing and swallowing dysfunction, which can be prepared by gelation, enzyme treatment, blade tenderization and other non-thermal technologies. Flavor enhancement/enrichment, irritant addition and packet sauces were recommended to compensate the impairment of chemical sensory. Molds, piping bag and 3D printing were suggested for refining appearance of pureed foods, and improving appetite of the elderly.

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Sensory perception changes of the elderly affect food behaviors and health.

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Soft, smooth, and moisty foods are more suitable for the elderly.

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Gelation and enzyme treatment are applied to modify the texture of aged food.

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Packet sauces may meet the heterogenetic flavor requirements of the elderly.

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Visually attractive food made by 3D printing can increase the appetite of elderly.

Relationship between Oral Hypofunction, and Protein Intake: A Cross-Sectional Study in Local Community-Dwelling Adults

Few studies have investigated the relationship between nutritional status and comprehensive assessment of oral hypofunction, especially protein intake-related sarcopenia. Thus, we explored these relationships in a large-scale cross-sectional cohort study using the seven-item evaluation for oral hypofunction and Diet History Questionnaire for nutritional assessment. We used the data from 1004 individuals who participated in the 2019 health survey of the residents of Tarumizu City, Kagoshima Prefecture, Japan for analysis. We found that individuals with oral hypofunction were significantly older with a lower skeletal muscle index. Although there were few foods that had a significant difference between the groups with and without oral hypofunction, the consumption of beans and meats was significantly lower in women and men in the oral hypofunction group, respectively. According to the lower limit of the tentative dietary goal defined in Japan, comprehensive evaluation of oral hypofunction was significantly and independently associated with protein intake in both men and women (odds ratio, 1.70; 95% confidence interval, 1.21-2.35). In conclusion, we found that oral hypofunction was associated with targeted protein intake for sarcopenia and frailty prevention in middle-aged and older community-dwelling adults. Comprehensive evaluation of oral function with intervention in cases of hypofunction could inform clinicians to better prevent sarcopenia.

Prosthetic rehabilitation status, dental prosthesis functionality and masticatory function in nursing home residents

OBJECTIVE

To evaluate the association of masticatory function with prosthetic rehabilitation status and dental prosthesis functionality in nursing home residents.

BACKGROUND

Prosthetic rehabilitation status and dental prosthesis functionality may adversely affect mastication of older people, and this relationship is underestimated in nursing home residents.

MATERIALS AND METHODS

This cross-sectional study included 179 nursing home residents who used dental prostheses [mean (SD) age: 78.9 (9.0) years]. Masticatory function data were determined by assessing (a) masticatory performance using two-colour chewing gum, and (b) swallowing thresholds by counting the number of peanut chewing cycles. Older adults were categorised as: (1) using dental prostheses in both jaws (n = 100) and (2) partially dentate using removable partial dental prostheses (RPDPs) or complete dentures (CDs) in only one jaw (n = 41), or (3) edentulous using CD in only one jaw (n = 38). Stability, retention, occlusion, vertical dimension and defects were considered in assessing dental prosthesis functionality.

RESULTS

Greater variance of hue (VOH) of the chewing gum and lower swallowing thresholds (worse masticatory function) was associated with edentulous using CD in only one jaw. Older adults wearing dental prostheses with poor occlusion and vertical dimensions presented worse masticatory function. Dental prosthesis stability was associated with lower VOH values. Higher number of chewing cycles while eating peanuts was associated with non-broken dental prosthesis use.

CONCLUSION

Edentulous participants using CD in only one jaw and non-functional dental prosthesis use negatively affect the masticatory function of nursing home residents.

Lower Number of Teeth Is Related to Higher Risks for ACVD and Death-Systematic Review and Meta-Analyses of Survival Data

Tooth loss reflects the endpoint of two major dental diseases: dental caries and periodontitis. These comprise 2% of the global burden of human diseases. A lower number of teeth has been associated with various systemic diseases, in particular, atherosclerotic cardiovascular diseases (ACVD). The aim was to summarize the evidence of tooth loss related to the risk for ACVD or death. Cohort studies with prospective follow-up data were retrieved from Medline-PubMed and EMBASE. Following the PRISMA guidelines, two reviewers independently selected articles, assessed the risk of bias, and extracted data on the number of teeth (tooth loss; exposure) and ACVD-related events and all-cause mortality (ACM) (outcome). A total of 75 articles were included of which 44 were qualified for meta-analysis. A lower number of teeth was related to a higher outcome risk; the pooled risk ratio (RR) for the cumulative incidence of ACVD ranged from 1.69 to 2.93, and for the cumulative incidence of ACM, the RR ranged from 1.76 to 2.27. The pooled multiple adjusted hazard ratio (HR) for the incidence density of ACVD ranged from 1.02 to 1.21, and for the incidence density of ACM, the HR ranged from 1.02 to 1.30. This systematic review and meta-analyses of survival data show that a lower number of teeth is a risk factor for both ACVD and death. Health care professionals should use this information to inform their patients and increase awareness on the importance of good dental health and increase efforts to prevent tooth loss.

Association between denture use, chewing ability, and all-cause mortality in middle-aged and older adults who exercised regularly in Korea

Herein, using data from the Korean Longitudinal Study of Aging (2006–2018), we evaluated denture use and chewing ability to determine the status of oral health in middle-aged adults who exercised regularly; further, we investigated the relationship of oral health with all-cause mortality. From the basic survey conducted in 2006, we interviewed 10,254 participants who were followed up until death. The participants were grouped based on regular exercise into REG (n = 3921) and non-REG (n = 6290) groups. The mortality rate was higher in the non-REG group than in the REG group (35.8% versus 26.9%; p < 0.001). The mortality rate was higher in denture users (versus non-denture users), non-drinkers (versus alcohol drinkers), and those on medical aid (versus national health insurance). The mortality rate was higher in participants with poor masticatory ability, lower education level, and poor subjective health perception (p < 0.001). Denture use and masticatory discomfort were not significant risk factors for mortality in the non-REG group (p > 0.05). In conclusion, masticatory discomfort was a risk factor for increased mortality in middle-aged Korean adults who exercised regularly, at least once a week. Thus, assessment of masticatory ability could be a useful indicator of life expectancy in middle-aged adults.

Does Last Year's Cost Predict the Present Cost? An Application of Machine Leaning for the Japanese Area-Basis Public Health Insurance Database

The increasing healthcare cost imposes a large economic burden for the Japanese government. Predicting the healthcare cost may be a useful tool for policy making. A database of the area-basis public health insurance of one city was analyzed to predict the medical healthcare cost by the dental healthcare cost with a machine learning strategy. The 30,340 subjects who had continued registration of the area-basis public health insurance of Ebina city during April 2017 to September 2018 were analyzed. The sum of the healthcare cost was JPY 13,548,831,930. The per capita healthcare cost was JPY 446,567. The proportion of medical healthcare cost, medication cost, and dental healthcare cost was 78%, 15%, and 7%, respectively. By the results of the neural network model, the medical healthcare cost proportionally depended on the medical healthcare cost of the previous year. The dental healthcare cost of the previous year had a reducing effect on the medical healthcare cost. However, the effect was very small. Oral health may be a risk for chronic diseases. However, when evaluated by the healthcare cost, its effect was very small during the observation period.

Association of Periodontal Status, Number of Teeth, and Obesity: A Cross-Sectional Study in Japan

Recent reports have shown an association between obesity and periodontitis, but the precise relationship between these conditions has yet to be clarified. The purpose of this study was to compare the status of periodontitis, tooth loss, and obesity. Participants comprised 235 patients at the Center for Medical and Dental Collaboration in Kanagawa Dental University Hospital between 2018 and 2020. Clinical examinations such as blood testing, body composition analysis, periodontal measurement, assessment of chewing ability, salivary testing, and oral malodor analysis were performed. Periodontal inflamed surface area (PISA) was significantly associated with the number of teeth and body mass index (BMI). The number of teeth was negatively associated with age, but positively with chewing ability. Chewing ability was associated negatively with age, and positively with high-sensitivity C-reactive protein (hsCRP). The level of methyl-mercaptan in breath and protein and leukocyte scores from salivary testing were positively associated with PISA. The rate of insufficient chewing ability was increased in subjects with hemoglobin (Hb)A1c ≥ 7%. The high PISA group showed increased hsCRP. BMI as an obesity marker was positively associated with PISA, indicating periodontal inflammation. Chewing ability was related to serum markers such as HbA1c and hsCRP.

Structure and Validity of Questionnaire for Oral Frail Screening

Oral frailty is defined as the mild decline in oral function and located at the early and reversible stage of frailty. Therefore, early detection and early treatment of oral frailty is very useful. Simple and easy questionnaires, such as an oral frailty checklist, have been widely used for the screening and enlightenment of oral frailty of the Japanese people. We evaluate the structure and validity of the oral frailty checklist. The questionnaire of oral frailty was distributed for the citizens more than 50 years old from December 2018 to January 2019. The structural validity of the questionnaire is analyzed by structural equation modeling (SEM). The characteristics of the items are analyzed by Item Response Theory (IRT). The data of 725 subjects (360 men, 359 women, 6 no answer, mean age 71.3 ± 9.05) are analyzed. The questionnaire consisted of three latent variables. Items of "Brushing teeth at least twice a day", "Regular attendance of dental clinic", and "Using denture", had low discrimination ability. The questionnaire used in this study is a useful tool for the screening of oral frailty. However, its scoring system needs to be improved.

Dental Hygienists' Practice in Perioperative Oral Care Management According to the Japanese Dental Hygienists Survey 2019

Perioperative oral care management is effective in the prevention of postoperative complications, and dental hygienists play an important role. The aim of this study was to elucidate the practice and substantial role of dental hygienists in perioperative oral care management. The Japan Dental Hygienists Association conducted a survey of the employment status of Japanese dental hygienists in 2019. Questionnaires were distributed to all 16,722 members, and 8932 were returned (collection rate: 53.4%). A total of 3560 dental hygienists were working at dental clinics and 1450 (38.2%) were performing perioperative oral care management. More than 90% of them implemented conventional oral care practice. Less than half of the dental hygienists implemented treatment concerning oral functions. Only 9.9% of dental hygienists recognized shortened hospital stay as an effect of perioperative oral care management. Dental hygienists who implemented both nutritional instruction and training of swallowing function or mouth rinsing instructions recognized the shortened hospital stay effect. Overall implementation of perioperative oral care management led to shortened hospital stay. Implementation of perioperative oral care management required knowledge and skills related to systemic health conditions. A stepwise educational program is necessary for perioperative oral care management to become commonplace for dental hygienists.

Mortality-and Health-Related Factors in a Community-Dwelling of Oldest-Older Adults at the Age of 90: A 10-Year Follow-Up Study

Mortality is obviously intended for epidemiological studies of community-dwelling older adults. There are several health-related factors associated with nutritional status and mortality. The aim of this study was to elucidate the risk factor for mortality in community-dwelling oldest-older adults at the age of 90 and clarify the structure of health-related factors associated with mortality. A 10-year follow-up study was performed for 93 subjects at the age of 90. The mean and median of their survival days were 2373 and 2581 days for women, and 1694 and 1793 days for men. By Cox's proportional hazards model, health-related factors associated with mortality were self-assessed for chewing ability, activities of daily living (ADLs), serum albumin, total cholesterol, serum creatinine, and gripping power for women but not for men. These factors interacted with each other, and the association of these factors was different in women and men. Self-assessed chewing ability was a powerful risk factor for mortality in women at the age of 90. It acted independently from nutritional status. For older adults, addressing healthy food choices together with improved oral functions is useful. However, risk factors for mortality may depend on the life stage of subjects. To investigate the risk factor for the mortality, the life course approach is necessary.

Optimal Examination Sites for Periodontal Disease Evaluation: Applying the Item Response Theory Graded Response Model

Periodontal examination data have a complex structure. For epidemiological studies, mass screenings, and public health use, a simple index that represents the periodontal condition is necessary. Periodontal indices for partial examination of selected teeth have been developed. However, the selected teeth vary between indices, and a justification for the selection of examination teeth has not been presented. We applied a graded response model based on the item response theory to select optimal examination teeth and sites that represent periodontal conditions. Data were obtained from 254 patients who participated in a multicenter follow-up study. Baseline data were obtained from initial follow-up. Optimal examination sites were selected using item information calculated by graded response modeling. Twelve sites—maxillary 2nd premolar (palatal-medial), 1st premolar (palatal-distal), canine (palatal-medial), lateral incisor (palatal-central), central incisor (palatal-distal) and mandibular 1st premolar (lingual, medial)—were selected. Mean values for clinical attachment level, probing pocket depth, and bleeding on probing by full mouth examinations were used for objective variables. Measuring the clinical parameters of these sites can predict the results of full mouth examination. For calculating the periodontal index by partial oral examination, a justification for the selection of examination sites is essential. This study presents an evidence-based partial examination methodology and its modeling.

Impact of the Serum Level of Albumin and Self-Assessed Chewing Ability on Mortality, QOL, and ADLs for Community-Dwelling Older Adults at the Age of 85: A 15 Year Follow up Study

Quality of life (QOL) and mortality are true endpoints of epidemiological or medical research, especially for community-dwelling older adults. Nutritional status and activities of daily living (ADLs) are associated with QOL and mortality. Good oral health status supports a good nutritional status. The aim of this study was to elucidate the complex structure of these important health-related factors. We surveyed 354 healthy older adults at the age of 85. Nutritional status was evaluated by the serum level of albumin. QOL, ADLs, self-assessed chewing ability, serum albumin level, and mortality during the 15 year follow up period were analyzed. Self-assessed chewing ability was associated with QOL and ADLs. Self-assessed chewing ability for slight-hard foods was associated with mortality in men. However, it was not associated with the serum albumin level. The serum albumin level was associated with mortality in women. These results indicate that maintaining good oral function is not enough. Nutritional instruction in accordance with oral function is indispensable for health promotion in older adults. When planning health promotion strategies for older adults, different strategies are needed for men and women.

Tooth-Level Analysis of Dental Caries in Primary Dentition in Myanmar Children

In developing countries, the prevalence of dental caries in children remains high, which means that implementing a simple and convenient classification is critical. The classification needs to be evidence-based and needs to reflect tooth-level information. In this study, the prevalence of dental caries in the primary dentition of 352 Myanmar school children at the ages of 5, 6, and 7 was analyzed at the tooth level to clarify the underlying data structure of the patterns of dental caries in the population. Ninety-three percent of subjects had caries in primary dentition and the mean number of decayed teeth in primary dentition was 7.54 ± 4.82. Based on the item response theory analysis, mixed-effect modeling, and Bayesian network analysis, we proposed the following classification: Group 1: No dental caries; Group 2: Dental caries in molar teeth or dental caries in maxillary anterior teeth; Group 3: Dental caries in both molar and maxillary anterior teeth; Group 4: Dental carries in mandibular anterior teeth. Dental caries (dmft) in the groups was different between groups. The results of characteristics of tooth-level information and classification presented in this study may be a useful instrument for the analysis of the data of dental caries prevalence in primary dentition.

Nutritional Status and Oral Frailty: A Community Based Study

Compromised oral health can alter food choices. Poor masticatory function leads to imbalanced food intake and undesirable nutritional status. The associations among nutritional status, oral health behavior, and self-assessed oral functions status were investigated using a community-based survey. In total, 701 subjects more than 50 years old living Ebina city located southwest of the capital Tokyo were investigated. The number of remaining teeth was counted by dental hygienists. Oral health behavior and self-assessed oral functions were evaluated by oral frailty checklist. Nutritional status was evaluated by the brief-type self-administered diet history questionnaire using Dietary Reference Intakes for Japanese as reference. More than 80% of subjects’ intakes of vitamin B₁₂, pantothenic acid, copper, and proteins were sufficient. In contrast, only 19% of subjects’ intake of vitamin A was sufficient and 35.5% for vitamin B₁. More than 90% of subjects’ intakes of vitamin D and vitamin K were sufficient. Only 35.5% of subjects’ intakes of dietary fiber were sufficient. Overall, 88.9% of subjects had excess salt. The number of remaining teeth was not correlated with nutritional intakes. Oral health behavior significantly correlated with nutritional intakes. Oral functions are important for food choice; however, oral functions were not directly correlated with nutritional intakes. Comprehensive health instructions including nutrition and oral health education is necessary for health promotion.

Oral Microbiome in Four Female Centenarians

The oral microbiome of healthy older adults has valuable information about a healthy microbiome. In this study, we collected and analyzed the oral microbiome of denture plaque and tongue coating samples from four female centenarians. After DNA extraction and purification, pyrosequencing of the V3–V4 hypervariable regions of the 16S rRNA was carried out. The bacterial taxonomy for each lead was assigned based on a search of the EzBioCloud 16S database. We obtained a total of 199,723 valid, quality-controlled reads for denture plaque and 210,750 reads for tongue coating. The reads were assigned 407 operational taxonomic units with a 97% identity cutoff. Twenty-nine species were detected in both denture plaque and tongue coatings from all subjects. Firmicutes was the most abundant phylum; the Streptococcus salivarius group was the most abundant species in both the denture plaque and tongue coatings; and the Fusobacterium nucleatum group was detected in all subjects. In the bacterial profile, species formed clusters composed of bacteria with a wide range of prevalence and abundance, not dependent on phyla; each cluster may have specific species that could be candidates for a core microbiome. Firmicutes and Veillonella were abundant phyla on both plaque and tongue coatings of centenarians.