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.

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.

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.

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 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.

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.

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 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 (β= -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.

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.

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.

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.

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.

Characterization of oral bacteria in the tongue coating of patients with halitosis using 16S rRNA analysis

There are many studies on the relationship between the tongue coating and halitosis, but few have evaluated the bacterial community present in the tongue coating. This study identified bacteria in the tongue coating in individuals with and without halitosis using 16S rRNA analysis. Forty subjects (mean age, 46.1 ± 15.8 years) who visited the halitosis clinic at the University Dental Hospital between 2016 and 2017 were divided into halitosis (n = 32) and non-halitosis (n = 8) groups according to results from an organoleptic test (OT). Additional measurements via gas chromatography (GC) and the Breathtron® instrument confirmed the groupings as the H₂S, CH₃SH, (CH₃)₂S, and total volatile sulphur compounds (VSC) levels were significantly higher in the halitosis group than in the non-halitosis group. Bacterial diversity was higher in the halitosis group; the median (quartile) values of the Shannon index were 4.46 (4.21, 4.67) in the halitosis group and 3.80 (3.45, 4.30) in the non-halitosis group. Additionally, the median (quartile) values of the Chao-1 index were 84.0 (77.2, 95.0) in the halitosis group and 71.3 (65.0, 81.5) in the non-halitosis group. These differences in bacterial composition and diversity may further the understanding of causes and treatments for halitosis.

Risk indicators of dental caries and gingivitis among 10-11-year-old students in Yangon, Myanmar

OBJECTIVES

To obtain basic data on dental caries and gingival status of students in Myanmar, and to identify related risk indicators, including socioeconomic conditions and oral health behaviours and habits.

STUDY DESIGN

This cross-sectional study enrolled 537 fifth-grade students in Myanmar. Oral health behaviours and dietary patterns of students were assessed using questionnaires. Oral examinations were conducted to identify dental caries and gingivitis, and the oral samples were obtained to determine the bacteria levels in dental plaque.

RESULTS

The dental caries prevalence was 68.5%, with a mean number of decayed teeth of 2.07 ± 2.15. The prevalence of gingivitis was 98.9%, and the mean number of inflamed gingival areas in the anterior region was 16.2 ± 5.4. No significant differences were found between the sexes in terms of dental caries and gingivitis. Oral hygiene was significantly poorer, and levels of bacteria in dental plaque were significantly higher in boys than in girls. Multiple linear regression tests were used to analyse the association between risk indicators and dental caries and gingivitis. Tooth brushing frequency, a daily habit of mouth rinsing, dental visit experience, consumption of sugary snacks and oral hygiene status were significantly associated with dental caries. Mother's occupation, tooth brushing frequency, consumption of sweet drinks, oral hygiene status and bacterial levels in dental plaque were significant predictors of gingivitis.

CONCLUSIONS

Myanmar students had a high prevalence of dental caries and gingivitis. Socioeconomic condition, oral hygiene status and oral health behaviours were all determined to be significant risk indicators.

The Oral Healthcare System in Japan

This paper describes the present Japanese oral healthcare system and outlines the future challenges and perspectives for Japan. Japan has developed a system for providing high-quality and appropriate health care efficiently through a universal health insurance system which has been in operation since 1961. This health insurance covers most restorative, prosthetic and oral surgery treatment. Therefore, all people can receive dental treatment at a relatively low cost, with the same fees applying throughout the nation. In Japan, public oral health services are provided by the local governments according to the life stage of their populations. These services are mainly conducted by private dental practitioners under contracts with local governments. National oral health data shows that the oral health of the Japanese population has improved over the last several decades. Future challenges and perspectives for Japanese dentistry include: tackling the regional differences in oral health, decreasing the cost of health expenditure, establishment of sustainable emergency oral healthcare services in times of disaster, and the development a new tele-dental system for remote areas without access to dental professionals.

Effects of oral health education in Myanmar preschool children and guardians

AIM

The aim of the present study was to investigate the effects of oral health education on preschool children's oral health status and habits, and their guardian's oral health knowledge.

METHODS

A 1-year interventional study was conducted for 201 preschool children from January 2016 to January 2017. A questionnaire survey and clinical oral examination were performed at baseline and at 1-year follow up. A 30-min oral health education session was given to children and their teachers and guardians separately by a dentist every 6 months. The impact of health education was evaluated by assessing the changes in guardians' questionnaires and children's oral health status during the 1-year period.

RESULTS

The mean oral health knowledge scores of guardians significantly increased from 8.0 ± 2.0 at baseline to 9.0 ± 2.5 at 1-year follow up (P < .001). Most oral health habits, except drinking water after eating, significantly improved at 1-year follow up. Significant decreases in debris score (P = .008) and gingival score (P < .001) were found.

CONCLUSION

Comprehensive oral health education was shown to improve guardians' knowledge of oral hygiene, and oral health habits and status of their children. It is necessary to adopt a comprehensive oral health-promotion program involving oral health-care professionals, parents, and teachers.

Prevalence and risk factors of halitosis in Japanese school children

BACKGROUND

Little data are available regarding halitosis in Japanese children. The aim of the current study was to investigate the prevalence and risk factors associated with halitosis in Japanese elementary and junior high school children.

METHODS

The subjects consisted of 520 elementary (1st-6th grade: boys, n = 284; girls, n = 236) and 248 junior high (7th-9th grade: boys, n = 136; girls, n = 112) school children aged 6-15 years in Saitama Prefecture, Japan. A self-administered questionnaire survey; halitosis measurement using an organoleptic assessment method; and clinical oral examination were conducted.

RESULTS

Overall, 44.9% of subjects had halitosis. The proportion of boys with halitosis was 43.6% and that of girls was 46.6%. On logistic regression analysis, grade and tongue coating were significant predictors of halitosis. The 7th-9th graders were significantly more likely to have halitosis than 1st-3rd graders (OR, 1.83; P = 0.007). Subjects with area of tongue coating score 2 or 3 were 5.51-fold more likely to present with halitosis (P < 0.001) than those with area of tongue coating score 0 or 1. Similarly, subjects with thickness of tongue coating score 2 or 3 were 3.28-fold more likely to have halitosis than those with thickness of tongue coating score 0 or 1 (P < 0.001).

CONCLUSIONS

Halitosis in the school children is not a rare condition; instead, its occurrence is relatively high. Therefore, inclusion of a halitosis prevention and management component in school oral health programs would lead to the promotion of overall oral health.

Association between self-reported and clinical oral health status in Belarusian adults

AIM

The aims of the present study were to determine characteristics of self-perception of oral health, and to investigate associations between self-reported status and clinical oral health status among Belarusian adults.

METHODS

A cross-sectional study, including a questionnaire survey and oral health examination, was conducted among 281 dental patients.

RESULTS

Of the participants, 74% were women; the mean ages of female and male participants were 35.9 ± 12.3 and 28.0 ± 10.3 years (P < 0.001), respectively. More than half of the participants (58%) described their oral health as negative. The number of decayed teeth (P < 0.001), missing teeth (P < 0.001), and teeth with bleeding on probing (P < 0.01) and deep periodontal pockets (P < 0.001) were significantly higher among participants who described their oral health as negative compared to their counterparts. Participants with better agreement between self-reported and clinical number of teeth had significantly lower numbers of decayed and missing teeth (P < 0.01). There was a significant relationship between participants' self-reported periodontal status and number of teeth with bleeding on probing and deep periodontal pockets (P < 0.05).

CONCLUSIONS

Self-perceived oral health was significantly associated with clinical oral health status in this study. Self-reporting methods could be useful for population-based oral health surveys in Belarus.

Validity of the self-reported number of natural teeth in Japanese adults

AIM

The aims of this research were to assess the validity of self-reporting of the number of teeth by comparing the number with that obtained through clinical dental examinations, and to investigate factors affecting the discordance between the two measures.

METHODS

Self-administered questionnaires and dental examinations were conducted among 1152 dentate community residents in Japan. The validity of the patients' reports of the number of teeth was assessed by comparing the self-reported number with that determined at the clinical examination. Factors affecting the absolute value of the difference between the self-reported number of teeth and the number at clinical examination were investigated using a multivariate analysis.

RESULTS

Overall, 47.5% of participants had perfect agreement in their self-report with the clinical examination. There was a slight tendency toward underestimation of the number of natural teeth by self-reporting. Pearson's correlation coefficient was 0.80, and the intraclass correlation coefficient was 0.78 for all patients. Decayed, filled, sound teeth, and fixed prosthetic pontics were significantly associated with the absolute value of the difference between self-reports and clinical examinations.

CONCLUSIONS

Patients' reported number of remaining teeth, the data for which were collected via the questionnaire, provided reasonably valid data on the actual number of teeth within a population group.

Association of oral health literacy with oral health behaviour and oral health status in Belarus

OBJECTIVES

To explore the level of oral health literacy among adults in Belarus, a former part of the Soviet Union, and to analyse the associations between oral health literacy, socio-demographics, health behaviour and oral health status.

BASIC RESEARCH DESIGN

A cross-sectional study. Participants: 281 adult (18-60 years old) dental patients.

MAIN OUTCOME MEASURE

The participants completed a self-administered questionnaire collecting information about socio-demographics and health behaviours, and oral health literacy test (the R-OHLI). Clinical oral examination followed the questionnaire survey.

RESULTS

Among participants, 68.7% had adequate, 18.9% had marginal and 12.4% inadequate oral health literacy levels. Females and those with higher education were more likely to have adequate oral health literacy (p<0.05 and p<0.001). Participants with adequate oral health literacy had fewer missing and more filled teeth than those with inadequate literacy (p<0.001). This association remained significant after adjusting for socio-demographics, behavioural characteristics and oral hygiene status (p<0.05 and p<0.001).

CONCLUSIONS

Adequate oral health literacy was strongly related with better oral health status. Improvement of oral health literacy should be addressed when developing community oral health promotions.

Factors associated with clinical and perceived oral malodor among dental students

The objective of this study was to determine the prevalence of and factors associated with clinical and perceived oral malodor among dental students. Clinical oral malodor was measured in 163 Malaysian dental students using organoleptic method and Oral ChromaTM and they were asked about their perception of self-oral malodor. Oral examination was performed to assess oral health status. Statistical analyses were performed using SPSS version 19.0. There were 52.7% students who had clinical oral malodor, while 19.0% students perceived they had oral malodor. The sensitivity (0.244) of self-perceived oral malodor was lower than its specificity (0.870). Tongue coating was closely associated with clinical oral malodor whereas high plaque index was closely associated with perceived oral malodor. These results showed that clinical oral malodor was prevalent among dental students, but students' perception of oral malodor did not always reflect actual clinical oral malodor. Furthermore, associating factors of clinical oral malodor differ from perceived oral malodor. The importance of controlling clinical oral malodor with proper tongue cleaning should be emphasized and dental students should be taught on the differences between clinical and perceived oral malodor in order to manage this problem.

Effectiveness of three oral hygiene regimens on oral malodor reduction: a randomized clinical trial

Background

Breath odor is a nuisance problem for many people around the world. Bad breath affects social interactions of people in daily life by causing personal discomfort and emotional stress. There are chemical and mechanical methods for controlling oral malodor. Many studies of various mouth rinse applications and tongue cleaning procedures have been conducted. However, few studies have compared the effect of simultaneous chemical and mechanical procedures on the reduction of volatile sulfur compounds (VSCs) in subjects with oral malodor. The purpose of this study was to assess the effects of different oral hygiene procedures on reduction of VSCs in subjects with oral malodor.

Methods

Thirty male volunteers who matched with study criteria were divided randomly into two groups. Both groups performed tooth brushing, mouth washing with chlorine dioxide, tongue cleaning and combination of those in different sequence for five weeks. Total VSCs of subjects were measured with a Breathtron®, and oral health status was also examined. Quantitative analyses were performed using the Statistical Package for Social Science (SPSS 16.0).

Results

There were no significant differences in oral health status between the two groups at the baseline. No significant decrease in oral malodor was detected after one week of tooth brushing. Significant reductions in VSCs were shown by adding mouthwash or tongue cleaning to tooth brushing from the second week to fourth week (P <0.01). The greatest reduction in VSCs was found at the fifth week after the practice of all three oral hygiene regimens.

Conclusions

Tooth brushing alone does not significantly reduce oral malodor. Mouth washing and tongue cleaning significantly reduce oral malodor, but combining tooth brushing, mouth washing and tongue cleaning regimens is most effective for oral malodor reduction. The results of this study could contribute to the formulation of appropriate preventive strategies against oral malodor not only for the general public but also for dental professionals serving as oral malodor-related service providers.

Trial registration

Registration number - ClinicalTrials.gov NCT02113137. Registration date – April 7th, 2014.

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-015-0549-9) contains supplementary material, which is available to authorized users.

Taste hyposensitivity in Japanese schoolchildren

Background

There is some research on taste disorder/hyposensitivity in special groups such as the elderly or patients presenting with specific taste problems, however few studies have been conducted among young populations. The objectives of this study were to estimate the prevalence of taste hyposensitivity and to investigate the relationship between taste hyposensitivity and oral health status in Japanese schoolchildren.

Methods

Subjects were 237 primary and 112 junior high school students in Saitama Prefecture, Japan. In total, 349 (boys: 181, girls: 168) students aged 6–15 years participated in the study. Oral examinations and whole-mouth taste tests using four tastes (sweet, salt, sour and bitter) solutions were conducted on the subjects. A subject who could not recognize the taste of the solution was defined as demonstrating hyposensitivity.

Results

Hyposensitivity was observed in 6.3% of all subjects for sweet-taste, 14.3% for salt-taste, 20.9% for sour-taste and 6.0% for bitter-taste. The prevalence of sweet, sour and bitter-taste hyposensitivity decreased as the subjects’ grade advanced. In contrast, the prevalence of salt-taste hyposensitivity increased in 7^th-9^th grade subjects. Furthermore, the prevalence of bitter-taste hyposensitivity was significantly higher in males than females among 1^st-3^rd graders.

Taste hyposensitivity had little association with oral health status, such as decayed teeth, filled teeth, dental plaque, gingival status and tongue coating.

Conclusions

In this study, taste hyposensitivity was observed in 6.0%-20.9% of the students. There was little association between taste hyposensitivity and oral health status. The current study implies that the factors affecting the taste hyposensitivity in children may different from those in the elderly. Therefore it is necessary to further investigate the causes of taste hyposensitivity among younger generation.

Effects of an oral health education program targeting oral malodor prevention in Japanese senior high school students

OBJECTIVE

Previous research has suggested that oral malodor could be a useful motivational tool for increasing the awareness of oral health in adolescents and improving their oral health behaviors. Hence, the aims of this research were: (1) to develop an oral health education program that included oral malodor prevention and (2) to test the effects of the program in Japanese senior high school students by comparing the changes of oral health outcomes between the intervention and control groups.

MATERIALS AND METHODS

Subjects were 163 Grade 1 and 135 Grade 2 senior high school students in Tokyo, Japan. A novel oral health education program, which incorporated prevention of oral malodor, was developed and conducted on all Grade 1 students (intervention group). Grade 2 students (control group) did not receive the program. Changes in oral health status from baseline to 1-year follow-up were compared between the intervention and control groups.

RESULTS

The intervention group, compared with the control group, had a significantly higher proportion of students who improved or maintained good oral health status (i.e. dental plaque, gingivitis, tongue coating and oral malodor). Among students in the intervention group, the change was more evident in subjects with detectable oral malodor at the commencement of the program.

CONCLUSIONS

An oral health education program focusing on the prevention of oral malodor is effective for promoting oral health among Japanese senior high school students. Therefore, embedding such a program in the school oral health curriculum would be beneficial for adolescents.

Association of hyposalivation with oral function, nutrition and oral health in community-dwelling elderly Thai

OBJECTIVES

This study was to analyze the association of hyposalivation with oral function, nutritional status and oral health in community-dwelling elderly Thai.

METHOD

The subjects were 612 elderly people (mean age = 68.8, SD 5.9 years). Oral function (tasting, speaking, swallowing and chewing) and Mini Nutritional Assessment (MNA) were evaluated. Oral examination investigated teeth and periodontal status. Both unstimulated and stimulated whole saliva were collected for 5 minutes.

RESULTS

Among all subjects, 14.4 % were classified within the hyposalivation. Hyposalivation was associated with gender, systemic disease, medication, and smoking. Subjects within the hyposalivation group had a higher number of decayed teeth and a higher prevalence of periodontitis than the normal salivation group (p < 0.05). The hyposalivation group also had a lower number of teeth present and a lower mean MNA score than the normal salivation group (p < 0.05). Logistic regression analysis showed that hyposalivation in both dentate and edentulous subjects was significantly associated with tasting, speaking, swallowing and chewing.

CONCLUSION

This study suggested that hyposalivation is a risk factor not only for dental caries and periodontal disease but also for taste disturbances, speaking problems, swallowing problems, poor chewing ability and malnutrition. Monitoring salivary flow is an important measure in the care of older people.

Oral health status and chewing ability is related to mini-nutritional assessment results in an older adult population in Thailand

In a cross-sectional study, we investigated the relationship of Mini-Nutrition Assessment (MNA) results with chewing ability tests and oral examinations (number of teeth present and functional tooth units (FTUs)). The participants were 612 older people (Mean [SD] age: 68.8 [5.9]). According to the MNA score, 25.1% of participants were categorized as having normal nutrition, 67.2% were categorized as at risk of malnourishment, and 7.7% were categorized as having malnutrition. The mean numbers of teeth present and FTUs were [15.5] and [8.9], respectively. The ANCOVA analyses adjusted for age and gender showed that participants with malnutrition had lower numbers of teeth present (8.8), FTUs (8.4), and chewing ability (6.8) than those with normal nutrition (13.3, 10.4 and 7.8) (p < 0.05). Nutritional status was associated with mean numbers of teeth present, FTUs, and chewing ability. Therefore, it was concluded that retention of natural teeth with appropriate numbers of FTUs by replacing missing teeth with dentures and improving chewing ability will help the reduce risk of malnutrition in older adults.

Factors influencing perceived oral health of Japanese middle-aged adults

The objective of this study was to analyze the relationships between subjective oral health symptoms and clinical oral health conditions on the perceived oral health of 1799 Japanese middle-aged adults. A self-administered questionnaire together with dental examinations was administered. A structural equation modeling analysis with Bayesian estimation was used to examine the factors influencing perceived oral health as a latent variable with 4 other latent variables: subjective oral health symptoms, clinical tooth conditions, clinical periodontal conditions, and other clinical oral conditions. For perceived oral health as the endogenous variable, only subjective oral health symptoms and clinical tooth conditions showed significant relationship. Clinical periodontal conditions and other clinical oral conditions did not show significant effects on the perceived oral health.

Association of clinical oral health status with self-rated oral health and GOHAI in Japanese adults

OBJECTIVE

The objective of this study was to investigate clinical oral health status relationships that affect quality of life (using the 12-item General Oral Health Assessment Index (GOHAI)) and self-rated oral health in a community of Japanese residents.

METHODS

459 residents of Yokote City, Japan aged 40-55 years had oral health examinations and completed self-administered questionnaires collecting data on age, gender, GOHAI items and self-rated oral health. Linear regression analysis was performed with GOHAI or self-rated oral health as a dependent variable and gender, age and indicators of oral health status as independent variables.

RESULTS

The GOHAI indicated 42.7% of subjects were concerned about the appearance of their teeth, 30.1% were worried about teeth problems and 27.5% concerned about sensitive teeth. Analyses showed that gender, decayed teeth, oral dryness and missing teeth were significantly associated with variation in GOHAI scores, and that gender, decayed teeth, oral dryness and oral hygiene were significantly associated with variation in self-rated oral health.

CONCLUSION

This study revealed that in this sample of Japanese adults aged 40-55 years, decayed teeth and oral dryness affected both GOHAI and self-rated oral health, whereas missing teeth affected GOHAI and oral hygiene affected self-rated oral health. Subjects did not recognise periodontal disease as a quality of life impacting condition or as a health problem.

Daily variation of oral malodour and related factors in community-dwelling elderly Thai

OBJECTIVES

The purposes of this study were (i) to estimate the prevalence of oral malodour, (ii) to evaluate the daily variation of oral malodour and (iii) to assess associations of volatile sulphur compound (VSC) concentrations with socio-demographics, health behaviours and oral health status in community-dwelling elderly Thai.

METHODS

The subjects were 428 dentate elderly people (67.6 ± 5.6 years) living in Phitsaulok, Thailand. Information on their socio-demographics, general health and health behaviours was obtained by a questionnaire. Their dental condition, periodontal status and tongue coating were clinically examined. Their flow rates and the pH of unstimulated saliva were also assessed. Oral malodour was measured at four different times of day using an Oral Chroma™.

RESULTS

The proportions of subjects diagnosed with oral malodour using the thresholds of H(2)S, CH(3)SH and (CH(3))(2) S were 60.5%, 62.9% and 80.7%, respectively. Concentrations of H(2)S showed significant daily variation. Linear regression analysis demonstrated the following significant associations: (i) oral malodour from H(2)S and thickness of the tongue coating, (ii) oral malodour from CH(3)SH and periodontal pocket depth of 5 mm or more and the presence of gingival bleeding and (iii) oral malodour from (CH(3))(2)S and systemic disease, medications and thickness of the tongue coating.

DISCUSSION

Oral malodour was shown to be prevalent among the elderly. Daily variation was observed in the concentration of H(2)S. Tongue coating, periodontal disease, systemic diseases and medications were related to oral malodour. Therefore, these factors should be taken into consideration in oral malodour treatment and prevention programmes for the elderly.

Social anxiety disorder in genuine halitosis patients

Background

There is a possibility that genuine halitosis patients' anxiety do not recover after oral malodor treatment due to their social anxiety disorder. The objective of this study was to investigate the influence of social anxiety disorder on the level of anxiety in genuine halitosis patients before and after treatment for oral malodor.

Methods

The subjects were 262 genuine halitosis patients who visited the Fresh Breath Clinic from March, 2008 to October, 2009. The subjects who had score 2 or higher by the organoleptic test were diagnosed as genuine halitosis patients. Gas chromatography (GC) was conducted before and after oral malodor treatment for the oral malodor measurement. Based on their risk of social anxiety disorder, subjects were divided into low- and high-risk groups using the Liebowitz Social Anxiety Scale (LSAS). The questions related to oral malodor and the clinical oral examination were both conducted before oral malodor treatment. The level of anxiety before and after oral malodor treatment was evaluated using the Visual Analogue Scale of Anxiety (VAAS).

Results

More than 20% of subjects had a score of 60 or more on the LSAS (high LSAS group). The mean age and the percentage of females were significantly higher in the high LSAS group compared to the low LSAS group. The high LSAS group was more likely to have problems associated with oral malodor and to adopt measures against oral malodor compared to the low LSAS group. The mean concentrations of H₂S and CH₃SH by GC significantly decreased after the oral malodor treatment in both LSAS groups. VAAS scores also significantly decreased after treatment in both LSAS groups. The logistic regression analysis indicated that the high LSAS group had a 2.28 times higher risk of having a post-VAAS score of 50 or more compared to the low LSAS group.

Conclusions

This study revealed that genuine halitosis patients with a strong trait of social anxiety disorder have difficulty overcoming their anxiety about oral malodor. Oral malodor treatment of genuine halitosis patients requires not only regular oral malodor treatment but also attention to social anxiety disorder.

Exploring taste hyposensitivity in Japanese senior high school students

AIM

The main objective of this study was to investigate the prevalence of taste hyposensitivity and the relationships between sex, oral health status, and eating habits with taste hyposensitivity in Japanese senior high school students.

METHODS

Oral examinations, sweet and salt whole-mouth taste tests, and a questionnaire about eating habits were conducted on 234 senior high school students. Factors affecting taste hyposensitivity were investigated using a multivariate analysis.

RESULTS

Sweet-taste hyposensitivity was observed in 7.3% of the students, and salt-taste hyposensitivity in 22.2%. Approximately 3% of the students had both sweet- and salt-taste hyposensitivity, and 22.6% had either sweet- or salt-taste hyposensitivity. In total, 26% had a taste hyposensitivity. There were significant relationships between the intake of instant noodles with sweet-taste hyposensitivity, and the intake of vegetables or isotonic drinks with salt-taste hyposensitivity.

CONCLUSIONS

There was a significant association between eating habits and taste hyposensitivity in Japanese senior high school students. Taste tests would be a helpful adjunct for students to recognize variations in taste sensitivity, and a questionnaire about their eating habits might provide an effective self-review of their eating habits, and therefore, provide motivation to change.

Effects of a mouthwash with chlorine dioxide on oral malodor and salivary bacteria: a randomized placebo-controlled 7-day trial

Background

Previous research has shown the oxidizing properties and microbiological efficacies of chlorine dioxide (ClO₂). Its clinical efficacies on oral malodor have been evaluated and reported only in short duration trials, moreover, no clinical studies have investigated its microbiological efficacies on periodontal and malodorous bacteria. Thus, the aim of this study was to assess the inhibitory effects of a mouthwash containing ClO₂ used for 7 days on morning oral malodor and on salivary periodontal and malodorous bacteria.

Methods/Design

A randomized, double blind, crossover, placebo-controlled trial was conducted among 15 healthy male volunteers, who were divided into 2 groups. Subjects were instructed to rinse with the experimental mouthwash containing ClO₂ or the placebo mouthwash, without ClO₂, twice per day for 7 days. After a one week washout period, each group then used the opposite mouthwash for 7 days. At baseline and after 7 days, oral malodor was evaluated with Organoleptic measurement (OM), and analyzed the concentrations of hydrogen sulfide (H₂S), methyl mercaptan (CH₃SH) and dimethyl sulfide ((CH₃)₂S), the main VSCs of human oral malodor, were assessed by gas chromatography (GC). Clinical outcome variables included plaque and gingival indices, and tongue coating index. The samples of saliva were microbiologically investigated. Quantitative and qualitative analyses were performed using the polymerase chain reaction-Invader method.

Results and Discussion

The baseline oral condition in healthy subjects in the 2 groups did not differ significantly. After rinsing with the mouthwash containing ClO₂ for 7 days, morning bad breath decreased as measured by the OM and reduced the concentrations of H₂S, CH₃SH and (CH₃)₂S measured by GC, were found. Moreover ClO₂ mouthwash used over a 7-day period appeared effective in reducing plaque, tongue coating accumulation and the counts of Fusobacterium nucleatum in saliva. Future research is needed to examine long-term effects, as well as effects on periodontal diseases and plaque accumulation in a well-defined sample of halitosis patients and broader population samples.

Trial registration

ClinicalTrials.gov NCT00748943