Frequency of Going Outdoors and Risk of Poor Oral Health Among Older Japanese Adults: A Longitudinal Cohort From the Japan Gerontological Evaluation Study.

BACKGROUND: The association between the frequency of going outdoors and the risk of poor oral health has been reported in several studies; however, the findings have been inconclusive. METHODS: We conducted a 3-year longitudinal study of 19,972 Japanese adults aged ≥65 years who reported no poor oral condition at baseline in 2013. The respondents rated their frequency of going outdoors in three categories (≤1, 2-3, or ≥4 times/week), and the oral conditions reported in 2016 included tooth loss, chewing difficulty, swallowing difficulty, dry mouth, and composite outcomes. The associations between the frequency of going outdoors and the risk of poor oral health were examined as relative risk ratios (RRs) and 95% confidence intervals (CIs) using multivariable Poisson regression, while mediation analysis was performed to investigate indirect effects. RESULTS: During the follow-up, 32.5% of participants developed poor oral health. In the mediation analysis, indirect effects were observed through low instrumental activities of daily living, depressive symptoms, little social network diversity, and underweight. Compared to going outdoors ≥4 times/week, the multivariable RRs of composite poor oral health conditions were 1.12 (95% CI, 1.05-1.20) for 2-3 times/week and 1.22 (95% CI, 1.07-1.39) for ≤1 time/week (P-trend < 0.001). Similar associations were observed for tooth loss, chewing difficulty, and swallowing difficulty; the corresponding RRs were 1.07 (95% CI, 0.97-1.19) and 1.36 (95% CI, 1.13-1.64) (P-trend = 0.002), 1.18 (95% CI, 1.06-1.32) and 1.30 (95% CI, 1.05-1.60) (P-trend < 0.001), and 1.15 (95% CI, 1.01-1.31) and 1.38 (95% CI, 1.08-1.77) (P-trend = 0.002), respectively. CONCLUSION: The frequency of going outdoors was inversely associated with the risk of poor oral health through several modifiable risk factors in the older population.

Changes in the utilization of outpatient and visiting dental care and per-attendance care cost by age groups during COVID-19 pandemic waves in Japan: A time-series analysis from LIFE study.

BACKGROUND: The influence of the coronavirus disease (COVID-19) pandemic on dental care utilization may have differed according to individual characteristics or type of dental care provision. This study aimed to evaluate the changes in dental care utilization and per-attendance costs by age group and type of dental care during the COVID-19 pandemic in Japan. METHODS: This time-series study used healthcare insurance claims data from 01/07/2019 to 09/27/2021 (143 weeks) from nine municipalities in Japan. Dental care utilization rate per week and average dental care cost per attendance by age groups (0-19y/20-64y/65-74y/≥ 75y) and types of dental care (outpatient/visiting) were used as outcome variables. COVID-19 pandemic waves in Japan were used as predictors: 1st (03/23/2020-05/17/2020), 2nd (06/22/2020-09/27/2020), 3rd (10/26/2020-02/21/2021), 4th (02/22/2021-06/07/2021), and 5th (07/05/2021-09/13/2021) waves. Fixed effect models were employed to estimate the proportional changes. RESULTS: In the fixed effect model, we observed large declines in dental care utilization during the 1st (17.0-22.0%) and 2nd waves (3.0-13.0%) compared to the non-pandemic wave period in all age groups. In contrast, the average dental care cost per attendance increased in all age groups by 5.2-8.6% during the 1st wave. CONCLUSIONS: During the initial wave of the COVID-19 pandemic in Japan, dental care utilization decreased in all age groups, whereas the average dental care cost per attendance increased. The COVID-19 pandemic may have changed the dental care provision pattern towards less frequent and more concentrated dental care to avoid the risk of infection.

Tooth loss mediates the association between smoking and an increased risk of dementia among older adults: The JAGES prospective cohort study.

AIM: Tooth loss has various causes; however, its cause-specific effects on health outcomes remain unclear. This study evaluated whether the association between past/current smoking and risk of dementia was mediated by tooth loss. MATERIALS AND METHODS: This 9-year-follow-up prospective cohort study targeted adults aged ≥65 years. Dementia incidence during 2013-2019, smoking status (never, past/current) in 2010 and the number of remaining teeth (≤19, ≥20) in 2013 were the outcome, exposure and mediator, respectively. We used causal mediation analysis to fit the Cox proportional hazards model and estimated the hazard ratio (HR) and 95% confidence interval (CI) of the natural indirect effect (NIE) of smoking on dementia incidence through tooth loss and their mediated proportions. RESULTS: Among 32,986 participants (mean age 72.6 years [1 SD = 5.4]; men 48.4%), the dementia incidence during follow-up was 2.11/100 person-years. Tooth loss significantly mediated the association between past/current smoking and dementia incidence; the NIE of fewer remaining teeth for past/current smokers compared to never smokers was HR = 1.03 (95% CI: 1.02-1.05), and the mediated proportion was 18.0%. CONCLUSIONS: Tooth loss significantly mediates the association between past/current smoking and an increased risk of dementia among older adults.

The association between objective and subjective oral health conditions and the presence of anorexia of aging among Japanese older Adults1.

Anorexia of aging is a risk factor for malnutrition among older adults. This study aimed to evaluate the association between objective and subjective oral health and anorexia among independent older adults. This cross-sectional study targeted independent older adults aged ≥65 years who participated in the Japan Gerontological Evaluation Study conducted in 2022. The outcome variable was the presence of anorexia, as assessed by the Simplified Nutritional Appetite Questionnaire. Exposure variables were dental status (≥20 teeth, 10-19 teeth with/without dentures, and 0-9 teeth with/without dentures) as objective oral health and oral health-related quality of life measured by five items of the short version of the Oral Impacts on Daily Performances (OIDP) (eating, speaking, smiling, emotional stability, and enjoying with others) as subjective oral health. We fitted the Poisson regression model, including possible confounders, and estimated prevalence ratios (PRs) and 95% confidence intervals. Among 19,787 participants (mean age: 74.6 years [1SD = 6.2], male: 48.5%), 9.0% were classified as having anorexia. After adjusting possible confounders, those with ≤19 teeth had a higher proportion of experiencing anorexia compared to those with ≥20 teeth; however, the association was less pronounced among those with dentures (0-9 teeth with dentures: PR = 1.48 [1.31-1.68], and 0-9 teeth without dentures: PR = 2.08 [1.65-2.63]). Even after adjusting for dental status, each item of OIDP was significantly associated with the presence of anorexia (all p < 0.05). The results showed that both objective and subjective poor oral health were significantly associated with a higher probability of developing anorexia of aging. Therefore, improving both objective and subjective oral health through appropriate dental care could contribute to maintaining appetite in later life.

Differences in prevalence of self-reported oral hypofunction between older adult patients with rheumatoid arthritis and the general older population: A cross-sectional study using propensity score matching.

OBJECTIVE: To examine the association between rheumatoid arthritis (RA) and oral hypofunction (OHF) using propensity score matching (PSM) to adjust for differences between older adults with RA and the general older adult population. METHODS: We conducted a cross-sectional survey among 189 older adults with RA in 2019 (mean age, 71.9 ± 3.6) and 47 178 independent older adult residents in 2016 (mean age, 71.6 ± 4.0), respectively. The questionnaire covered information on socio-demographic characteristics and OHF for both groups. Age, sex, educational level and smoking history were used to determine PSM. Prevalence ratios (PRs) and 95% confidence intervals (CIs) of self-reported OHF (fewer remaining teeth, decreased masticatory function, deterioration of swallowing function and oral dryness) were estimated using Poisson regressions. RESULT: OHF was observed in 44.4% of patients with RA and 27.5% of residents. Before PSM, the prevalence of OHF among patients with RA was higher than that of residents (PR, 1.75; 95% CI, 1.50-2.05). After PSM, there were 189 patients with RA and residents, and the prevalence of OHF among patients with RA was still higher (PR, 1.61; 95% CI, 1.22-2.13). Poisson regression showed that the prevalence of 19 or fewer teeth (PR, 1.06; 95% CI, 0.82-1.36), difficulties eating tough foods (PR, 1.18; 95% CI, 0.90-1.55), difficulties swallowing tea or soup (PR, 1.77; 95% CI, 1.19-2.63), and dry mouth (PR, 2.79; 95% CI, 1.90-4.07) was higher among patients with RA than residents. CONCLUSION: Compared with the general older adult population, patients with RA have a higher prevalence of self-reported OHF.

Dental prosthesis use is associated with higher protein intake among older adults with tooth loss.

BACKGROUND: Tooth loss is associated with reduced protein intake, which leads to sarcopenia and frailty in older adults. OBJECTIVE: To evaluate the protective effect of dental prostheses on decreased protein intake in older adults with tooth loss. METHODS: This cross-sectional study was based on a self-reported questionnaire targeting older adults. Data were obtained from the Iwanuma Survey of the Japan Gerontological Evaluation Study. We used % energy intake (%E) of total protein as the outcome and the use of dental prostheses and number of remaining teeth as explanatory variables. We estimated the controlled direct effects of tooth loss by fixing the use/non-use of dental prostheses based on a causal mediation analysis, including possible confounders. RESULTS: Among 2095 participants, the mean age was 81.1 years (1SD = 5.1), and 43.9% were men. The average protein intake was 17.4%E (1SD = 3.4) of the total energy intake. Among participants with ≥20, 10-19 and 0-9 remaining teeth, the average protein intake was 17.7%E, 17.2%E/17.4%E and 17.0%E/15.4%E (with/without a dental prosthesis), respectively. Compared to participants with ≥20 remaining teeth, those with 10-19 remaining teeth without a dental prosthesis did not have a significantly different total protein intake (p > .05). Among those with 0-9 remaining teeth without a dental prosthesis, total protein intake was significantly low (-2.31%, p < .001); however, the use of dental prostheses mitigated the association by 79.4% (p < .001). CONCLUSION: Our results suggest that prosthodontic treatment could contribute to maintaining protein intake in older adults with severe tooth loss.

Lower socio-economic status in adolescence is associated with poor oral health at an older age: Mediation by social and behavioural factors.

AIM: To examine the mediators between lower socio-economic status (SES) in adolescence and oral health at an older age to uncover the underlying mechanisms of the association. METHODS: Participants (n = 21 536) aged ≥65 years from the Japan Gerontological Evaluation Study were evaluated. The dependent variables were self-rated chewing difficulty and having ≤19 remaining teeth. The main independent variable was self-perceived SES in adolescence. The Karlson-Holm-Breen method was used for mediation analysis. RESULTS: Mean age of the participants was 74.8 years (standard deviation = 6.4), and 51.5% were female. Overall, 5598 (26.0%) participants reported chewing difficulty and 9404 (43.7%) had ≤19 remaining teeth. Lower SES in adolescence was associated with a higher prevalence of chewing difficulty (odds ratio [OR] = 1.38, 95%confidence interval [CI] = 1.29-1.48; total effect). After controlling for mediators, OR for lower SES in adolescence was 1.22 (95%CI = 1.13-1.30; direct effect) and 1.13 (95%CI = 1.11-1.16; indirect effect). Mediators, prominently the number of teeth and income, explained 39.3% of the associations. Lower SES in adolescence increased the odds of ≤19 remaining teeth by OR = 1.23 (95% CI = 1.16-1.31; total effect). After controlling for mediators, the OR for lower SES in adolescence was 1.03 (95%CI = 0.97-1.10; direct effect) and 1.19 (95%CI = 1.16-1.23; indirect effect). Mediators, prominently educational attainment, explained 85.0% of the associations. CONCLUSIONS: Lower SES in adolescence was associated with poor oral health at an older age through mediators. Approaches that consider social determinants from the beginning of the life course are required.

[Association between periodontal pocket depth determined during dental check-ups and new onset of diabetes in community residents: the LIFE study].

Objectives　Recent studies have shown a bidirectional association between diabetes and periodontal disease. However, the longitudinal association between periodontal pocket depth and new onset of diabetes remains controversial. Therefore, this study aimed to examine the association between periodontal pocket depth and new onset of diabetes using dental check-up data in a community-based population.Methods　The study comprised 5,163 participants aged≥20 years (mean age±standard deviation, 57.4±13.9 years; women, 66.3%) who underwent dental check-ups between April 2016 and March 2019 in a Tokyo ward. We classified the participants into three groups using community periodontal index codes from dental check-ups: healthy periodontal pocket group, periodontal pocket 4-5 mm group, and periodontal pocket ≥6 mm group. The participants were followed until the end of March 2020. Additionally, data on individuals who developed diabetes in the same ward were acquired from the National Health Insurance and Latter-Stage Older Persons Health Care System using ICD-10 codes. As the study outcome, we identified individuals who developed diabetes after the dental check-up date. Diabetes incidence rates were compared using the log-rank test and Cox regression analysis. Additionally, we performed a sensitivity analysis using a similar framework.Results　The log-rank test showed that the cumulative incidence of diabetes between the three groups was significantly different (P<0.01). A Cox regression analysis model adjusted for sex, age, smoking habits, number of teeth present, and oral hygiene status showed that the diabetes development hazard ratio (HR) for the periodontal pocket ≥6 mm group was 1.44 (95% confidence interval [CI]; 1.04-2.00) when compared with that of the healthy periodontal pocket group. In the sensitivity analysis of individuals aged ≥40 years, the HR for the periodontal pocket ≥6 mm group was 1.55 (95% CI; 1.11-2.16) when compared with that of the healthy periodontal pocket group. Similarly, among men aged ≥40 years, the HR for the periodontal pocket ≥6 mm group was 1.72 (95% CI; 1.04-2.85) when compared with that of the healthy periodontal pocket group. However, no significant association between new onset of diabetes and periodontal pocket depth was found for women aged ≥40 years (HR=1.39, 95% CI; 0.89-2.18).Conclusion　This The study suggests a longitudinal association between periodontal pocket depth and new onset of diabetes. The association was particularly pronounced in men aged ≥40 years. Therefore, men aged <40 years should maintain good oral health through appropriate dental health guidance to prevent the future development of diabetes.

Yogurt product intake and reduction of tooth loss risk in a Japanese community.

AIM: To evaluate the longitudinal association between yogurt product intake and oral health in a population-based study. MATERIALS AND METHODS: This study included 1967 Japanese residents aged 40-79 years who underwent dental examinations in 2012. Among them, 1469 participants were followed up in 2017 for the incidence of tooth loss, which was defined as two or more teeth lost over 5 years. The intake of yogurt products, defined as yogurt and lactic acid beverages, was estimated using a semi-quantitative food frequency questionnaire. The composition of the salivary microbiota was evaluated. RESULTS: The Poisson regression model showed that a higher intake of yogurt products was negatively associated with the incidence of tooth loss (p for trend = .020), adjusted for potential confounding factors. Mediation analysis confirmed that periodontal condition partly mediated the effect of yogurt product intake on tooth loss, while dental caries experience did not. Additionally, we confirmed the association of a high intake of yogurt products with a low percentage of the salivary microbiota pattern, which was associated with poor oral health. CONCLUSION: These findings suggest that the intake of yogurt products is associated with a lower risk of tooth loss resulting from periodontal disease, probably via modulation of the oral microbiome composition.

Number of teeth, denture wearing and cognitive function in relation to nutritional status in residents of nursing homes.

BACKGROUND: Although statistical associations between tooth loss and cognitive decline have been reported, there are few previous studies on denture wearing. Additionally, it remains unclear whether nutritional status mediates this association. OBJECTIVE: Our purpose was to test for the hypothesis that the association between the number of teeth and denture wearing with cognitive function is mediated by nutritional status in residents of nursing homes. MATERIALS AND METHODS: We enrolled 162 participants who required long-term care (mean age: 87.7 ± 7.5 years, 26 men and 136 women) and were admitted to eight nursing homes in Fukuoka city, from September 2013 to March 2014. A trained dentist conducted dental and swallowing examinations, and the care-staff assessed nutritional status, comorbid conditions and cognitive function using the Clinical Dementia Rating (CDR). RESULTS: Poisson regression analysis showed that 0-19 teeth without dentures were associated with severe cognitive impairment (CDR 3) (prevalence ratio = 2.00; 95% confidence interval: 1.13-3.55) after adjustment for sex, age, suspected swallowing dysfunction and comorbid conditions. Mediation analysis confirmed that the nutritional status as a mediator of this association (the percentage mediated effect through nutritional status was 23.1%). CONCLUSION: There is an association between dental status and cognitive impairment in elder individuals, and dentures and poor nutrition are involved in this association. However, due to the cross-sectional design of this study, there is a possibility that this association is bidirectional.

Association between periodontitis and fibrotic progression of non-alcoholic fatty liver among Japanese adults.

AIM: Non-alcoholic fatty liver (NAFL) is known to develop into liver fibrosis, which increases the risk of liver cirrhosis and liver cancer. The association between periodontal condition and fibrotic progression of NAFL is unclear. This study aimed to clarify this longitudinal association. MATERIALS AND METHODS: Among 4812 participants aged 35-64 years undergoing annual health check-ups between 2003 and 2004, and follow-up 5 years later, 392 participants were diagnosed with NAFL. After excluding participants with liver fibrosis at baseline, 341 participants were followed up for 5 years. NAFL disease fibrosis score of ≥-1.455 was used to evaluate the probability of the presence of liver fibrosis. RESULTS: During the follow-up period, 10.6% of participants progressed to liver fibrosis. A higher clinical attachment level (CAL) tended to be associated with the incidence of liver fibrosis in the logistic regression analysis (odds ratio [OR] 1.82, 95% confidence interval [CI], 0.94-3.49, p = .074). The stratified analysis by obesity revealed a significant association with higher CAL in obese participants (OR 2.87, 95% CI, 1.23-6.69, p = .015), but not in non-obese participants. CONCLUSION: Higher CAL was associated with an increased probability of liver fibrosis in obese adults with NAFL.

Association between frequency of laughter and oral health among community-dwelling older adults: a population-based cross-sectional study in Japan.

PURPOSE: Oral health has been reported to have an impact on the activities of daily life such as chewing, eating, and laughing, while psychological factors such as depression and loneliness have been reported to affect oral health. Little is known, however, about the association between laughter and oral health in older adults. This study examined the bidirectional association between the frequency of daily laughter and oral health in community-dwelling older Japanese adults. METHODS: Our cross-sectional study employed data from the 2013 Japan Gerontological Evaluation Study's self-reported survey, which included 11,239 male and 12,799 female community-dwelling independent individuals aged 65 years or older. We defined the oral health status by the number of remaining teeth. The association between the self-reported frequency of laughter (almost every day, 1-5 days per week, 1-3 days per month, or almost never) and oral health was examined using logistic regression analysis. RESULTS: The participants with 10 or more teeth were significantly more likely to laugh compared with the edentulous participants, after adjusting for all covariates. Compared with those who almost never laughed, those who laughed 1-5 days per week were significantly less likely to be edentulous. After stratifying by sex, similar results were found only in the men for both analyses. CONCLUSION: There was a significant bidirectional association between frequency of laughter and oral health that was independent of socioeconomic and lifestyle factors among older adults.

Longitudinal Associations of Toothbrushing With Obesity and Hyperglycemia.

BACKGROUND: Toothbrushing is a health-related lifestyle habit and has been reported to contribute not only to oral health but also to some parameters of general health; however, little research has been conducted to understand the association of the frequency and timing of toothbrushing with the development of comprehensive metabolic abnormalities, with consideration of oral health condition. In this study, using longitudinal data, we examined this association in Japanese adults, adjusting for periodontal condition. METHODS: A 5-year longitudinal study was performed with 4,537 participants between 35 and 64 years old who underwent an annual dental examination in both 2003 and 2008. Data about toothbrushing habits and metabolic abnormalities, such as obesity, hyperglycemia, diabetes, hypertension, hypertriglyceridemia, and low levels of high-density lipoprotein-cholesterol, were analyzed using Poisson regression analysis. RESULTS: The percentage of participants with a toothbrushing frequency ≤1 time/day was 29.4%, and that for those not brushing their teeth at night was 21.4%. The incidences of obesity and hyperglycemia after 5 years were 5.5% and 28.4%, respectively. A toothbrushing frequency ≤1 time/day was associated with development of obesity (prevalence rate ratio [PRR] 1.77; 95% confidence interval [CI], 1.12-2.80), after adjusting for periodontal condition and potential risk factors. A significant association between not brushing teeth at night and hyperglycemia (PRR 1.30; 95% CI, 1.02-1.66) was observed in participants with toothbrushing frequency of 1 time/day. No association was found between toothbrushing habits and other metabolic abnormalities. CONCLUSIONS: This study suggests that toothbrushing habits are associated with the development of obesity and hyperglycemia.

New Insights in the Natural Organic Matter Fouling Mechanism of Polyamide and Nanocomposite Multiwalled Carbon Nanotubes-Polyamide Membranes.

Polyamide (PA) membranes comprise most of the reverse osmosis membranes currently used for desalination and water purification. However, their fouling mechanisms with natural organic matter (NOM) is still not completely understood. In this work, we studied three different types of PA membranes: a laboratory made PA, a commercial PA, and a multiwalled carbon nanotube (CNT-PA nanocomposite membrane during cross-flow measurements by NaCl solutions including NOM, humic acid (HA), or alginate, respectively). Molecular dynamic simulations were also used to understand the fouling process of NOM down to its molecular scale. Low molecular weight humic acid binds to the surface cavities on the PA structures that leads to irreversible adsorption induced by the high surface roughness. In addition, the larger alginate molecules show a different mechanism, due to their larger size and their ability to change shape from the globule type to the uncoiled state. Specifically, alginate molecules either bind through Ca2+ bridges or they uncoil and spread on the surface. This work shows that carbon nanotubes can help to decrease roughness and polymer mobility on the surfaces of the membranes at the molecular scale, which represents a novel method to design antifouling membranes.

Relationship of toothbrushing to metabolic syndrome in middle-aged adults.

AIM: To examine the effect of toothbrushing on the development of metabolic syndrome (MetS), including assessment of periodontal status, in middle-aged adults. METHODS: This 5-year follow-up retrospective study was performed in 3,722 participants (2,897 males and 825 females) aged 35-64 years who underwent both medical check-ups and dental examinations. Metabolic components included obesity, elevated triglycerides, blood pressure, fasting glucose and reduced high-density lipoprotein. Toothbrushing frequency was assessed using a questionnaire. Periodontal disease was defined as having at least one site with a pocket depth of ≥4 mm. Logistic regression analysis was performed to evaluate the relationship between toothbrushing frequency at the baseline examination and the development of MetS (≥3 components). RESULTS: During follow-up, 11.1% of participants developed MetS. After adjusting for potential confounders including periodontal disease, participants with more frequent daily toothbrushing tended to have significantly lower odds of developing MetS (p for trend = .01). The risk of development of MetS was significantly lower in participants brushing teeth ≥3 times/day than in those brushing teeth ≤1 time/day (odds ratio = 0.64, 95% confidence interval = 0.45-0.92). CONCLUSIONS: Frequent daily toothbrushing was associated with lower risk of development of MetS.

Decreased cognitive function is associated with dysphagia risk in nursing home older residents.

OBJECTIVE: To examine the association between cognitive function and dysphagia risk among Japanese nursing home residents. BACKGROUND: Reduction in cognitive function can influence the intake of food during swallowing, and may be an aggravating factor in dysphagia. METHODS: This cross-sectional study included 236 residents aged ≥60 years from eight nursing homes. Screening of dysphagia, especially aspiration risk, was conducted using the Modified Water Swallow Test, whose scores from one to three were classified as at risk of dysphagia. Cognitive function was evaluated using Mini-Mental State Examination (MMSE). Number of teeth and occlusal support were evaluated by clinical examination. The participants were stratified into dentulous and edentulous groups, because the number of teeth could influence swallowing function. The odds ratio (OR) and 95% confidence interval (CI) for dysphagia risk based on the scores of MMSE were calculated using logistic regression. Demographic characteristics, activity of daily living, comorbidities, health behaviour and occlusal support were used as covariates. RESULTS: Among the 236 participants (111 dentulous participants and 125 edentulous participants) included in our analysis, 16.9% belonged to risk of dysphagia. Dentulous participants with higher scores of MMSE tended to have significantly lower odds of dysphagia risk after adjusting for covariates (OR = 0.87, 95% CI = 0.80-0.96). Despite the lack of significant differences, edentulous participants with higher score of MMSE tended to have lower odds of dysphagia risk (OR = 0.92, 95% CI = 0.83-1.00). CONCLUSION: Decreased cognitive function may be an independent predictor of dysphagia among dentulous and edentulous adults.

Tooth loss and metabolic syndrome in middle-aged Japanese adults.

AIM: Metabolic syndrome is associated with periodontal disease and dental caries; however, little attention has been given to the association between metabolic syndrome and tooth loss, which is the endpoint of these two diseases. This study examined this association in middle-aged adults over a 5-year period. METHODS: A retrospective study was performed in 2107 participants (1718 males and 389 females) aged 35-60 years who underwent annual dental check-ups, to evaluate tooth loss and metabolic components, including obesity, elevated triglycerides, blood pressure, fasting glucose, and reduced high-density lipoprotein. Logistic regression analysis was performed to evaluate the association between metabolic syndrome (≥3 components) at the baseline examination and tooth loss. RESULTS: Over a 5-year period, 10.8% of the participants lost at least one tooth. Compared to those with no metabolic components, participants with ≥3 components had an increased risk of tooth loss (odds ratio = 1.54; 95% confidence interval: 1.01-2.37), adjusting for age, gender, dental caries experience, attachment loss, oral hygiene status, number of teeth, tooth brushing frequency, smoking, and occupational status. CONCLUSIONS: Metabolic syndrome was associated with the incidence of tooth loss among middle-aged adults.

Serum antibody to Porphyromonas gingivalis and periodontitis progression: the Hisayama Study.

AIM: To assess the effectiveness of serum titres of antibody to Porphyromonas gingivalis in the prediction of periodontitis progression in a community-dwelling adult population. MATERIALS AND METHODS: This 4-year follow-up cohort study included 183 Japanese individuals (75 men and 108 women) aged 40-49 years. The clinical attachment level was measured at two sites on all teeth present at baseline and follow-up, and periodontitis progression was defined as progression in attachment loss of ≥3 mm at ≥2 measurement sites. Serum titres of antibody to Porphyromonas gingivalis were evaluated at baseline and served as the primary predictor variable for periodontitis progression. RESULTS: Periodontitis progression was found in 8.7% subjects. In a multivariate logistic regression model, higher titres of antibody to Porphyromonas gingivalis and male gender were significantly associated with greater odds of periodontitis progression, even after adjustment for other confounding variables (titres of antibody to Porphyromonas gingivalis per 10 units: odds ratio, 1.66; 95% confidence interval, 1.16-2.36; male gender: odds ratio, 4.13; 95% confidence interval, 1.20-14.27). CONCLUSIONS: Elevated serum titres of antibody to Porphyromonas gingivalis may be a risk factor for periodontitis progression.

Chewing xylitol gum improves self-rated and objective indicators of oral health status under conditions interrupting regular oral hygiene.

Chewing xylitol gum provides oral health benefits including inhibiting Streptococcus mutans plaque. It is thought to be especially effective in conditions where it is difficult to perform daily oral cleaning. Our study aim was to determine the effects of chewing xylitol gum on self-rated and objective oral health status under a condition interfering with oral hygiene maintenance. A randomized controlled intervention trial was conducted on 55 healthy ≥ 20-year-old men recruited from the Japan Ground Self Defense Force who were undergoing field training. Participants were randomly assigned to a test group (chewing gum; n = 27) or a control group (no gum; n = 28) and the researchers were blinded to the group assignments. The Visual Analog Scale (VAS) scores of oral conditions subjectively evaluated oral health, and the stimulated salivary bacteria quantity objectively evaluated oral health 1 day before field training (baseline) and 4 days after the beginning of field training (follow-up). VAS scores of all three oral conditions significantly increased in the control group (malodor: p < 0.001; discomfort: p < 0.001; dryness: p < 0.001), but only two VAS scores increased in the test group (malodor: p = 0.021; discomfort: p = 0.002). The number of salivary total bacteria significantly increased in the control group (p < 0.01), while no significant change was observed in the test group (p = 0.668). Chewing xylitol gum positively affects self-rated and objective oral health status by controlling oral hygiene under conditions that interfere with oral hygiene maintenance.

Impact of loss of removable dentures on oral health after the great East Japan earthquake: a retrospective cohort study.

PURPOSE: The Great East Japan Earthquake in March 2011 destroyed many communities, and as a result many older victims lost their removable dentures. No previous studies have documented the prevalence of denture loss after a natural disaster or examined its negative impact. Therefore, investigation of the consequences of such a disaster on oral health is of major importance from a public health viewpoint. MATERIALS AND METHODS: Three to five months after the disaster, questionnaire surveys were conducted in two coastal towns, Ogatu and Oshika, located in the area of Ishinomaki city, Miyagi prefecture. Among the survey participants, 715 individuals had used one or more removable dentures before the disaster, and these comprised the population analyzed. The effect of denture loss on oral health-related quality life (OHRQoL) was examined by a modified Poisson regression approach with adjustment for sex, age, subjective household economic status, dental caries, tooth mobility, psychological distress (K6), access to a dental clinic, physical activity, and town of residence. RESULTS: There were 123 (17.2%) participants who had lost their dentures. In comparison with participants who had not lost their dentures, those lacking dentures showed a significantly higher relative risk for eating difficulties (RR = 2.65, 95%CI = 1.90-3.69), speech problems (RR = 4.37, 95%CI = 2.46-7.76), embarrassment upon smiling, laughing, or showing their teeth (RR = 5.32, 95%CI = 2.34-12.1), emotional distress (RR = 2.38, 95%CI = 1.41-4.03), and problems related to social interaction (RR = 6.97, 95%CI = 1.75-27.7). CONCLUSIONS: Denture loss appeared to impair eating and speaking ability, thus discouraging communication with others. Public health intervention after major natural disasters should include dental care.