Association Between Oral Malodor and Dementia: An 11-Year Follow-Up Study in Japan.

Background: As infrequent social interaction is a potential risk of dementia, oral malodor may increase the risk of dementia, including Alzheimer's disease. Objective: This study investigated the association between malodor and dementia. Methods: We used the Japan Public Health Center-based Prospective Study data obtained at Yokote City. A total of 1,493 individuals aged 56 to 75 years underwent a dental examination and self-reported survey from May 2005 to January 2006. Follow-up for the onset of dementia was conducted using long-term care insurance data from 2006 to 2016. Hazard ratios of oral malodor on dementia were estimated by the Cox proportional hazards model. The inverse probability-weighted Cox model was used as a sensitivity analysis. Results: The study comprised 1493 participants (53.6% women) with a mean age of 65.6 (SD = 5.8) years old; at the end of the follow-up, 6.4% (n = 96) developed dementia, and the percentage was 20.7 in severe malodor group. Throughout 15274.133 person-years of follow-up, the average incidence rate for the onset of dementia per 1000 person-years was 6.29. The highest incidence rate was seen in participants with severe malodor (22.4 per 1000 person-years). After adjusting for confounders, compared to those with no malodor, there was a 3.8 (95% confidence interval: 1.5 to 9.4) times greater hazard of developing dementia in participants with severe malodor. The inverse probability weighted Cox model confirmed the same trend with an adjusted marginal hazard ratio of 4.4 (1.2 to 16.4). CONCLUSIONS: A significant association between oral malodor and the onset of dementia exists.

Simplifying Oral health evaluation: a novel approach through single-item surveys.

BACKGROUND: This study adopts a novel approach of using single-item surveys to simplify the assessment of oral health status and behaviors among Japanese private sector employees. We aimed to establish the validity of self-reported oral health in relation to clinical dental examinations, and to elucidate the relationship between oral diseases, health behaviors, and self-assessments. A secondary aim was to explore the association of self-rated oral health with oral health behaviors. MATERIALS AND METHODS: Self-administered questionnaires and dental examinations were obtained from 2262 Japanese private sector employees. Workers self-rated their overall oral health status according to five choices: "very good," "good," "fair," "poor," or "bad." Self-reports were then compared with the results of clinical dental examinations, which included measuring the oral hygiene index (DI-S), the number of decayed teeth, periodontal status (Community Periodontal Index) and number of missing teeth. Convergent validity was also tested by examining the correlations of self-reported oral health status with oral health behaviors. RESULTS: Overall, 30.8% of workers reported their oral health as "poor" or "bad." "Poor" or "bad" oral health status was significantly correlated with missing teeth, periodontitis, and decayed teeth. However, lower correlations were found for gingivitis and the oral hygiene index. Most self-reported oral health behaviors were correlated with self-rated oral health; exceptions were "tooth brushing instructions received in a dental clinic," "having a primary-care dentist," and "habitual snacking between meals." CONCLUSIONS: Self-rated oral health provides reasonably valid data, and correlated well with clinically assessed oral health status, including dental caries, periodontal status, and tooth loss. Convergent validity was also found for oral health behaviors. TRIAL REGISTRATION: Clinical trial registration number: UMIN000023011 (UMIN-CTR). Date of clinical trial registration: 06/07/2016.

Determining the most appropriate socioeconomic status indicator for describing inequalities in dental visits by Japanese older people.

OBJECTIVES: This study examined the association between various socioeconomic status (SES) indicators and dental visits among older Japanese. BACKGROUND: When examining health inequalities, an adequate indicator of SES should be applied. In older adults, wealth and pensions are considered more appropriate indicators of SES than education and income, but few studies have examined. METHODS: This cross-sectional study used data from 12 391 individuals aged 65 years or older from the 2016 Japan Gerontological Evaluation Study (JAGES). The Slope Index of Inequality (SII) and the Relative Index of Inequality (RII) were applied to examine the association of education, income, wealth and pensions with dental visits for treatment and check-up adjusting for covariates. RESULTS: The mean age of the participants was 74.0 ± 6.2 years. In the previous year, 56.3% of participants had visited a dentist for a check-up, and 65.9% had visited for treatment. Inequalities in dental treatment visits were observed for wealth, pensions and income rather than education. Income was not significantly associated with check-up visits. Wealth showed the largest association with dental visits for treatment [(SII 0.09, 95% CI 0.06 to 0.13), (RII 1.14, 95% CI 1.09 to 1.21)] and check-up [(SII 0.08, 95% CI 0.05 to 0.12), (RII 1.16, 95% CI 1.09 to 1.23)]. CONCLUSION: When measuring inequalities in access to dental care among the older population, wealth and pensions could be important indicators of SES.

Association of Stressful Life Events With Oral Health Among Japanese Workers.

BACKGROUND: Psychological stress can cause various mental and physical health problems. The previous results on stress and oral health are inconsistent, possibly because of the narrow stress measurements. We aimed to examine the association between a broader range of stressful life events and oral health among workers. METHODS: This cross-sectional study analyzed anonymous individual data from a national survey in Japan. Data on stressful life events, oral health problems which are one or more of tooth pain, gum swelling/bleeding, and difficulty chewing, and covariates were obtained using a self-reported questionnaire. Covariates used included gender, age group, and disease under treatment. Logistic regression analysis was used to estimate the association between stressful life events and oral health problems. We then estimated the causal treatment effects of stress using the augmented inverse-probability weighting (AIPW) method. RESULTS: Among the 274,881 subjects, 152,850 men (55.6%) and 122,031 women (44.4%) with a mean age of 47.0 (standard deviation, 14.4) years, 4.0% reported oral health problems, with a prevalence of 2.1% among those without any stress. The prevalence increased with stress score, reaching 15.4% for those with the maximum stress score. The adjusted odds ratio of this group compared to those without any stress was 9.2 (95% confidence interval [CI], 8.2-10.3). The estimated prevalence of oral health problems by the AIPW analysis was 2.2% (95% CI, 2.1-2.3%) for those without any stress and 14.4% (95% CI, 12.1-16.7%) for those with the maximum stress scores. CONCLUSION: There was a clear dose-response association between stressful life events and oral health problems.

Recent dental visits and family caregiving among individuals with dental symptoms: A nationwide cross-sectional study in Japan.

OBJECTIVES: With the increasing number of family caregivers due to the ageing population, physical and mental health problems among caregivers are of concern. However, few studies have evaluated their oral health. This study aimed to evaluate the association between being a family caregiver and recent dental visits for dental symptoms in Japan, with consideration of gender. METHODS: A cross-sectional study was conducted using the 2016 Comprehensive Survey of Living Conditions (CSLC) in Japan. Participants with dental symptoms were included in this study. The primary outcome was recent dental visits. The exposure variable of interest was being a primary caregiver for a family member requiring long-term care. A logistic regression analysis was conducted adjusting for contributing factors such as age, gender, marital status, working hours per week, education, household expenditure per month, self-rated health and the interaction between gender and caregiving. A stratified analysis by gender was also performed. RESULTS: Of the 5100 eligible participants, 233 (4.6%) were family caregivers. Of all participants, 2746 (53.8%) reported dental visits. The adjusted odds ratio (aOR) of family caregivers having recent dental visits was 0.83 (95% confidence interval [CI], 0.64-1.09). In a gender stratified analysis, family caregivers were less likely to visit dental clinics than were non-family caregivers in the male subsample (aOR: 0.56, 95% CI: 0.34-0.92) but not in the female subsample (aOR: 0.99, 95% CI: 0.72-1.38). CONCLUSIONS: The findings indicate that family caregivers, especially male caregivers, had fewer dental visits than non-family caregivers. These findings suggest the need to improve the accessibility of dental clinics to family caregivers with dental symptoms.

Association of oral health with various work problems: a cross-sectional study of Japanese workers.

BACKGROUND: Oral diseases affect quality of life and known to decrease productivity. We examined the impact of oral health status on various types of work problems. METHODS: This cross-sectional study used data from an internet-based self-report questionnaire survey administered to workers in Japan. Responses to the questionnaire regarding seven types of oral health-related work problems (1. Stress; 2. Lack of focus; 3. Lack of sleep; 4. Lack of energy; 5. Lack of communication due to halitosis; 6. Lack of communication due to appearance; 7. Lack of ability due to dental-related pain) were investigated and statistically analyzed. Explanatory variables were self-reported oral health status, number of teeth, and gum bleeding. To examine the association of oral health with the presence of work problems, logistic regression analysis was used to estimate the odds ratio (OR) and 95% confidence interval (CI). Age, sex, educational attainment, income, the presence of diabetes, and industrial classifications were used as the covariates. RESULTS: A total of 3,930 workers (mean age: 43.3 (SD = 11.7), 2,057 males and 1,873 females) were included. Overall, a total of 6.2% of workers reported having at least one oral health-related work problem in the past year, whereas 21.8% of those with poor self-reported oral health reported work problems. Workers with poor self-reported oral health were 3.58 (95% CI (1.70-7.56) times higher odds of reporting work problems than those with excellent self-reported oral health. CONCLUSIONS: Oral health was found to be associated with various work problems. Oral health promotion policies are needed in the workplace.

Dental Utilization Stratified by the Purpose of Visit: A Population-Based Study in Japan.

BACKGROUND: This study aimed to provide a stratified description of dental visit utilisation by Japanese residents based on patient age, sex, prefecture, and the purpose of the visits. METHODS: This cross-sectional study used the National Database of Health Insurance Claims of Japan to identify participants visiting dental clinics in Japan (April 2018-March 2019). Dental care utilisation by populations stratified by age, sex, and prefecture was assessed. We estimated the slope index of inequality (SII) and relative index of inequality (RII) to evaluate regional differences based on regional income and education. RESULTS: Amongst the Japanese population, 18.6% utilised preventive dental care visits; 59,709,084 participants visited dental clinics, with children aged 5 to 9 years having the highest proportion. SII and RII were higher for preventive dental visits than those for treatments in all settings. The largest regional differences for preventive care were observed in SII of children aged 5 to 9 years and in RII of men in their 30s and women aged 80 years and older. CONCLUSIONS: This nationwide population-based study revealed that the proportion of people utilising preventive dental care in Japan was low, with regional differences. Preventive care needs to be more easily accessible and available to improve the oral health of residents. The above findings may provide an important basis for improving policies related to dental care for residents.

Association between place of dental check-ups and work absenteeism among Japanese workers.

OBJECTIVES: Dental check-ups at the workplace provide the opportunity for early detection of dental diseases. Dental check-ups during working hours could reduce the number of days of absence from work due to visits to dental clinics outside the workplace. Although health check-ups are provided to workers in Japan, dental check-ups is not mandatory. This study aimed to determine the association between the place of dental check-ups and absenteeism due to visits to the dental clinic. METHODS: This cross-sectional study used data from an online self-reported worker survey conducted for 2 weeks in March 2017. We applied linear regression analysis with robust variance to determine the association between the place of dental check-ups and absenteeism due to dental clinic visits while adjusting for sociodemographic, health, and oral health covariates. RESULTS: The average age of the 3930 participants was 43.3 ± 11.7 years, and 52.3% were male. The number of days of absenteeism due to dental clinic visits in the past year for those who received check-ups only at the dental clinic and at the workplace were 0.57 ± 2.67 days and 0.21 ± 1.20 days, respectively. After adjusting for covariates, it was found that those who received dental check-ups at the workplace had 0.35 (95% CI, 0.12-0.58) fewer days of absence than those who received dental check-ups at the dental clinic. CONCLUSION: Workers who received dental check-ups at the workplace were associated with fewer days of absence due to dental visits than those who received at the dental clinic.

A cross-sectional study of the association between periodontitis and physical activity in the Japanese population.

OBJECTIVE: The aim of this study was to determine whether physical activity (PA) is associated with periodontitis in the Japanese population. BACKGROUND: The potential association between PA and periodontitis has not been thoroughly investigated in the Japanese population. METHODS: We used cross-sectional data from the Japan Public Health Center-based Prospective Study for the Next-Generation Oral Health Study. Periodontitis was determined by a full-mouth periodontal examination. PA was assessed using a validated questionnaire. We performed multivariable ordinal logistic regression analyses to assess the association of total PA (the first quintile was set as the reference category) with periodontitis (three categories: no/mild, moderate, and severe), stratified by sex. The associations of periodontitis with domain- and intensity-specific PA were also studied in separate logistic regression models. RESULTS: This study included 2160 Japanese adults [1414 women and 746 men; mean (standard deviation) age 58.1 (9.6) years]. After adjusting for potential confounders, total PA was inversely associated with the presence and severity of periodontitis in women. The multivariable-adjusted odds ratios (95% confidence intervals) for periodontitis in the second to fifth quintiles (compared with the first quintile) of total PA were 0.81 (0.59-1.12), 0.74 (0.53-1.02), 0.77 (0.55-1.06), and 0.64 (0.46-0.89), respectively (p for trend = .01). We did not find different results when we further investigated the associations of periodontitis with domain- and intensity-specific PA. By contrast, PA was not associated with periodontitis in men. CONCLUSION: Total PA had an inverse, linear association with the presence and severity of periodontitis in Japanese women but not in Japanese men. Further prospective studies are required to determine the association between PA and periodontitis.

Association of overtime work duration with oral health-related quality of life in Japanese workers.

PURPOSE: Overtime work is associated with a risk of developing various diseases, including oral diseases. Oral Health-Related Quality of Life (OHRQoL) is a more comprehensive assessment than those of individual diseases and can be affected by longer working hours. METHODS: This cross-sectional study examined the association of overtime work duration with OHRQoL. Data were obtained from an online survey of Japanese workers in February 2016. OHRQoL was assessed using the Oral Health Impact Profile-49 (OHIP-49). Poisson regression with robust variance was used to estimate the ratio of means and 95% confidence intervals (CI) of overtime work duration for OHIP-49 scores after adjusting for sociodemographic and health behavior covariates. RESULTS: Of 2,764 (2,178 male and 586 female) workers (mean age, 44.6 ± 10.0 years), those with longer duration of overtime work tended to exhibit poorer OHRQoL. The mean OHIP-49 scores of those who did not work overtime and worked for ≥5 h overtime were 27.93 ± 28.53 and 40.97 ± 38.86, respectively. After adjusting for covariates, compared to those who did not work overtime, the mean OHIP-49 score was 1.41 times higher (95% CI 1.38-1.44) for those who worked for ≥5 h overtime. CONCLUSION: Longer overtime work duration was associated with poor OHRQoL.

Concerning perceived and clinically-measured levels of halitosis.

The different types of self-reported halitosis complaints include those where one feels that one's breath smells bad, where one feels that one has bad breath because of the attitudes of others, and where others have pointed out the presence of bad breath. The results of previous studies comparing the objective and subjectives measures of halitosis are inconsistent, and few studies have used gas chromatography (GC) to measure halitosis in a large sample. This study aimed to examine the objectively measured halitosis levels based on the reasons individuals are concerned about halitosis. We included 2063 patients who visited the halitosis clinic at a university dental hospital. Halitosis was assessed using GC, self-administered questionnaires, and oral examinations. Levels of volatile sulphur compounds (VSCs; H2S, CH3SH, and (CH3)2S) were set as objective measures of halitosis. Patients were grouped based on their answers to 'What made you concerned about bad breath?' into groups: 'self-perceived,' 'attitudes of others,' 'told by others,' and other reasons. Univariate and multivariable linear regression analyses were performed to examine factors associated with VSCs and objective halitosis levels. Age, sex, oral health status, smoking, drinking, and breakfast habits were used as confounders. Patients who answered 'told by others' (n= 691, 33.5%) showed the highest VSCs. Individuals whose halitosis was pointed out by others had higher objectively measured halitosis levels, while those concerned about the attitudes of others or perceived their own halitosis had lower objectively measured halitosis levels. These results suggest that the objective level of halitosis can differ on the basis of the reason underlying an individual's concern about their bad breath. Categorizing halitosis complaints and comparing them with objective halitosis levels may help reduce the anxiety of those who are concerned about halitosis and confirm the need for intervention for those with objective halitosis.

Association of visual display terminal time with prevalence of temporomandibular disorder among Japanese workers.

OBJECTIVES: Visual display terminal (VDT) time has been reported to affect the development of temporomandibular disorders (TMDs). However, no study has investigated the association between VDT time at and outside of work with TMDs Adjusting for known TMJ risk factors. This study aimed to investigate whether TMDs were associated with VDT time at and outside of work after adjusting for various working conditions in Japanese workers. METHODS: This cross-sectional study was based on an internet survey of 3930 workers (2057 men and 1873 women), The TMD Screening Questionnaire (SQ-TMD), occupational factors, VDT time at and outside of work, psychosocial factors, and habits were assessed. We applied logistic regression to estimate the odds ratio (OR) of VDT time on SQ-TMD with adjustment for confounders. RESULTS: The mean age of the respondents was 43.3 ± 11.7 years, and 778 (19.8%) and 3152 (80.2%) subjects were at high and low TMD-related symptoms (TRS). Logistic regression analysis adjusting for all covariates (Model 2), the prevalence of high TRS was significantly higher among those with VDT time at work of 60-179 min (OR = 1.52, 95% CI 1.18-1.94), 180-359 min (OR = 1.27, 95% CI 1.00-1.62), and more than 360 min (OR = 1.44, 95% CI 1.10-1.88) compared to those with 0-59 min. However, there was no significant difference in the prevalence of high TRS for VDT time outside of work. CONCLUSION: VDT time at work, but not VDT time outside of work, influences the prevalence of TRS. Since the association between VDT time at work and the prevalence of TRS was found even after adjusting for sociopsychological factors and habits generally associated with TMD, further investigation of other factors is needed.

Association of marital status and access to dental care among the Japanese population: a cross-sectional study.

BACKGROUND: Health disparities according to marital status have been reported worldwide. Although spouses provide an important social network that influences heath behaviors, limited studies have examined the association between marital status and access to dental care. Therefore, this study aimed to analyze the association between marital status and access to dental care. METHODS: A secondary analysis of the 2013 Comprehensive Survey of Living Conditions in Japan which is a national survey, was performed in this study. Out of 367,766 respondents, 4111 respondents, aged over 40 years who selected oral symptoms as their most concerning subjective symptom were recruited as participants. The independent variable of interest was marital status-married or non-married (single, divorced, widowed); and the dependent variable was access to dental care. We performed Poisson regression analyses stratified by sex with adjustment for age, educational status, employment, equivalent household expenditure, and smoking habits. RESULTS: Among respondents who reported oral symptoms, 3024 were married, and 1087 were non-married. Further, 29.4% and 40.4% of married and non-married men, respectively, did not receive dental treatment for their symptoms. Meanwhile, 27.5% and 25.0% of married and non-married women, respectively, did not receive dental treatment for their symptoms. The prevalence ratio for not receiving dental treatment was significantly higher among non-married men (prevalence ratio: 1.33; 95% confidence interval: 1.14-1.56) than among married men. However, no significant association was observed among women. CONCLUSIONS: Non-married men were highly unlikely to receive dental treatment than married men, while no significant association was observed among women. The results implicate the importance of implementing a public dental health policy for protecting the dental health of non-married individuals.

Characteristics of Hospitals Employing Dentists, and Utilization of Dental Care Services for Hospitalized Patients in Japan: A Nationwide Cross-Sectional Study.

Dental care for hospitalized patients can improve nutritional status and feeding function while reducing complications. However, such care in Japan is not uniformly provided. This investigation examined the presence and characteristics of hospitals where dentists work and the collaboration between medical and dental teams. This cross-sectional study involves 7205 hospitals using the administrative reports on the Hospital Bed Function of 2018. Indicators described were the proportion of hospitals employing dentists, those providing perioperative oral care, and those with a nutrition support team (NST) that included dentists. A two-level logistic regression model was performed using hospital-based and secondary medical area-based factors to identify factors associated with hospitals employing dentists and dental care services. Some hospitals had poor medical and dental collaboration, even those with dentists, and no-dentist hospitals had rare medical and dental collaboration. Factors positively associated with hospitals that employed dentists were diagnosis-procedure-combination-hospital types, the Japanese government-established hospitals compared with hospitals established by public organizations, among others. In conclusion, the present study found poor medical and dental collaboration was observed in some hospitals and that hospital type, region, and hospital founders were associated with the performance of collaborative medical and dental care.

Associations of the number of remaining natural teeth and oral health behaviors with subjective chewing problems based on the Thailand National Oral Health Survey 2017.

PURPOSE: Few studies have examined the association of oral health behaviors with chewing ability.This study aimed to investigate the associations between the number of remaining natural teeth and oral health behaviors with subjective chewing ability among older Thai adults. METHODS: Analysis was carried out using data from the 8th Thailand National Oral Health Survey. Subjective chewing problems were assessed using self-reported questionnaires, and the number of remaining teeth by oral examination. Poisson regression with sampling weights was used to calculate the prevalence ratios (PRs) and 95% confidence intervals (CIs) for having chewing problems. RESULTS: Of the 2,310 participants (mean age, 67.2 ± 4.5 years), 53.3% had chewing problems. After adjusting for all covariates, significantly higher PRs for having chewing problems were observed among the participants without interdental cleaning (PR, 1.32; 95% CI, 1.06-1.65), without night-time brushing (PR, 1.12; 95% CI, 1.01-1.25), who were edentulous (PR, 1.16; 95% CI, 1.02-1.31), had urgent dental treatment within the past 12 months (PR, 1.15; 95% CI, 1.06-1.24), and who brushed for <2 min (PR, 1.10; 95% CI, 1.02-1.20). CONCLUSION: The number of remaining natural teeth and oral health behaviors were significantly associated with subjective chewing problems.

Evaluation of occlusal status of Japanese adults based on functional tooth units.

OBJECTIVES: Although extensive national oral health data on dental caries and periodontal diseases in Japan are available, few studies have assessed the occlusal status of the Japanese population, and none are based on national survey data. The presence and prosthodontic conditions of the molar region are important for masticatory function, and the functional tooth unit (FTU) approach can be used to evaluate the occlusal status. Thus, using the national oral health survey data, this study investigated the occlusal status of the Japanese population using FTU. METHODS: Overall, 3,605 adults (aged ≥20 years) who participated in the 2011 Japanese national oral health survey were included. FTUs were used as indices for evaluating the occlusal status. FTUs were calculated according to sex, age group, and the number of teeth present, and their associations were further analysed. RESULTS: The number of teeth present, posterior teeth, and FTUs decreased with age in both men and women. In the age group of those ≥60 years, all only natural teeth-FTU (n-FTU) and natural teeth and artificial teeth from fixed prostheses or implant-supported FTU (nif-FTU) scores were <8. The total-FTU scores of all age groups, except the 60-69 and 70-79 years age groups, were >10. CONCLUSION: This is the first study to use FTUs and national oral health survey data to investigate the occlusal status in the Japanese population. People aged ≥60 years who have low n-FTU or natural teeth and artificial teeth from fixed prostheses or implant-supported FTU scores or those aged 60-70 years who have the lowest total-FTU scores require careful evaluation of masticatory performance.

Periodontal health predicts self-rated general health: A time-lagged cohort study.

OBJECTIVES: There is limited evidence of a temporal relationship between periodontal diseases and self-perceived general health. To plug this knowledge gap, we aimed to assess how periodontal health affects future self-rated health (SRH). METHODS: We collected data from five waves of an annual nationwide Japanese survey of dental patients from 2015 to 2019. The analysis of repeated measurements included 9306 observations from 4242 patients aged 20 years or older. The clinical periodontitis measurements were bleeding on probing, deepest periodontal pocket depth and most severe clinical attachment loss (CAL). We used a self-administered questionnaire to collect data on sociodemographic characteristics, diabetes history, health behaviour, SRH and self-reported periodontitis. We applied 2-level ordered logistic regression models for repeated measurements to examine the relationships between SRH (time t) and 1-year-lagged periodontal health (time t-1) after adjusting for covariates. RESULTS: The percentage of SRH responses recorded at time t as 'good', 'moderate' and 'poor' were 36.9%, 52.4% and 10.7%, respectively. Multivariate analyses showed that the risk of poorer SRH at time t increased in patients with CAL ≥7 mm (odds ratio [OR] = 1.15, 95% confidence interval [CI] = 1.02-1.30), those who reported bleeding gums (OR = 1.33, 95% CI = 1.21-1.46) and those who perceived swollen gums (OR = 1.40, 95% CI = 1.26-1.56) at time t-1. Sensitivity analyses using the 4-year follow-up model and 3-year-lagged cohort model also showed consistent results. CONCLUSION: Periodontitis shows a gradual contribution to future SRH in dental patients, even after adjusting for sociodemographic characteristics, general health and health-related behaviours.

Association between exposure to secondhand smoking at home and tooth loss in Japan: A cross-sectional analysis of data from the 2016 National Health and Nutrition Survey.

INTRODUCTION: Tooth loss affects oral health and physical and social functions. With widespread population aging, its prevalence is increasing. Secondhand smoking is a risk factor for oral diseases; however, in Japan, there are currently no regulations restricting exposure to secondhand smoke at home. This cross-sectional study examined the association between secondhand smoking at home and tooth loss among Japanese adults. METHODS: The study examined secondary data from the 2016 National Health and Nutrition Survey, Japan. The self-reported responses of 18812 non-smokers aged ≥20 years were analyzed. The association between exposure to secondhand smoke at home and number of teeth was examined through multiple linear regression with multiple imputation. To obtain a more normal distribution, logarithmic transformation was applied to the number of teeth that deviated substantially from a normal distribution. Adjustments were made for sex, age, occupation, household size, dental check-up within the past year, and exposure to secondhand smoke outside the home. RESULTS: Overall, 8.4% of the respondents were exposed to secondhand smoking at home almost every day; this percentage was larger among younger respondents, who also had more teeth than the older respondents. Although the univariate linear regression did not show a positive association between exposure to secondhand smoke and tooth loss, the multivariate-adjusted analysis revealed that respondents who were exposed to secondhand smoke at home almost every day had fewer teeth (ß= -0.04; 95% CI: -0.07 - -0.01). CONCLUSIONS: The present results suggest that exposure to secondhand smoke at home increases the risk of tooth loss.

Inequalities in Periodontal Disease According to Insurance Schemes in Thailand.

Few studies have considered the effects of insurance on periodontal disease. We aimed to investigate the association between insurance schemes and periodontal disease among adults, using Thailand's National Oral Health Survey (2017) data. A modified Community Periodontal Index was used to measure periodontal disease. Insurance schemes were categorized into the Universal Coverage Scheme (UCS), Civil Servant Medical Benefit Scheme (CSMBS), Social Security Scheme (SSS), and "others". Poisson regression was applied to estimate the prevalence ratios (PRs) of insurance schemes for periodontal disease, with adjustment for age, gender, residential location, education attainment, and income. The data of 4534 participants (mean age, 39.6 ± 2.9 years; 2194 men, 2340 women) were analyzed. The proportions of participants with gingivitis or periodontitis were 87.6% and 25.9%, respectively. In covariate adjusted models, lowest education (PRs, 1.03; 95% CI, 1.01-1.06) and UCS (PRs, 1.05; 95% CI, 1.02-1.08) yielded significantly higher PRs for gingivitis, whereas lowest education (PRs, 1.20; 95% CI, 1.05-1.37) and UCS (PRs, 1.17; 95% CI, 1.02-1.34) yielded substantially higher PRs for periodontitis. Insurance schemes may be social predictors of periodontal disease. For better oral health, reduced insurance inequalities are required to increase access to regular dental visits and utilization in Thailand.

Multilevel Analysis of the Association of Dental-Hygienist-Related Factors on Regular Dental Check-Up Behavior.

Few studies have examined the factors related to dental clinics during dental check-ups. We examined the association between dental-hygienist-related factors and patients' regular dental check-ups. This nationwide cross-sectional study was based on a survey conducted in Japan in 2014. The analyzed population included 12,139 patients from 1181 dental clinics. We used three-level Poisson regression analysis, considering patient‒clinic‒prefecture, to examine the association of dental-hygienist-related factors with dental check-up behavior. Patients attending treatment and regular check-ups constituted 63.0% and 37.0%, respectively. The adjusted prevalence ratios (PRs) for patients undergoing regular dental check-ups at dental clinics with dedicated dental hygienists' units, spending ≥20 min in patient education (compared to 0 min), and with three or more dental hygienists (compared to 0 hygienists) available were 1.17 (95% confidence interval [CI]: 1.06-1.30), 1.25 (95%CI: 1.07-1.46), and 2.05 (95%CI: 1.64-2.56), respectively. The median PR indicates that when a patient randomly moves to another dental clinic with more regular dental check-ups, this prevalence increased 1.69 times. These results suggest that dental check-up behavior is determined not only by individual factors but also dental-clinic-level factors. Improving the dental-hygienist-related factors is necessary to encourage people to visit dentists for regular check-ups.