Effect of Antimicrobial Photodynamic Therapy on the Tongue Dorsum on Reducing Halitosis and the Duration of the Effect: A Randomized Clinical Trial.

Antimicrobial photodynamic therapy (PDT) is a treatment that is gaining popularity in modern clinical medicine. However, little is known about the effect of PDT alone on reducing oral halitosis and the duration of the effect. This trial examined the effect of PDT on the tongue dorsum on reducing oral halitosis and the duration of the effect. This study was approved by the Ethics Committee of Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, and Okayama University Hospital (CRB20-015), and it was registered in the Japan Registry of Clinical Trials (jRCTs061200060). Twenty-two participants were randomly assigned to two groups: an intervention group and control group. PDT was performed in the intervention group using red laser emission and methylene blue gel on the middle and posterior area of the tongue dorsum. The concentration of volatile sulfur compounds, bacterial count on the tongue dorsum, probing pocket depth, bleeding on probing, and simplified oral debris index score were determined before and 1 week after PDT. The Mann-Whitney U test was used to assess the significance of the differences in each parameter between the two groups. We found that the hydrogen sulfide concentration and bacterial count on the tongue dorsum were decreased in the intervention group, but there was no statistically significant difference between the two groups. These results indicated that performing only PDT on the tongue dorsum may not contribute to reducing halitosis.

Association between oral condition and subjective psychological well-being among older adults attending a university hospital dental clinic: A cross-sectional study.

Positive psychological well-being has a favorable impact on survival rates in both healthy and unhealthy populations. Oral health is also associated with psychological well-being, is multidimensional in nature, and includes physical, psychological, emotional, and social domains that are integral to overall health and well-being. This study aimed to identify the associations between individual and environmental characteristics, oral condition and nutritional status in relation to subjective well-being among older adults using the Wilson and Cleary conceptual model. The participants were older adults (age ≥ 60 years) attending a university hospital. Subjective well-being was assessed using the World Health Organization-5 Well-Being Index, oral condition was assessed based on the number of bacteria in the tongue coating, oral wettability, tongue pressure, occlusal force, oral diadochokinesis, and masticatory ability, and subjective swallowing function was assessed using the Eating Assessment Tool, number of remaining teeth, and number of functional teeth. In addition, factors related to well-being, including social networks, life-space mobility, nutritional status, smoking history, drinking history, and medical history were assessed. In the analysis, structural equation modeling was used to investigate the association between oral condition and subjective well-being. Confirmatory factor analysis revealed oral condition as a latent variable, including tongue pressure, oral diadochokinesis /pa/, /ta/, /ka/, occlusal force, masticatory ability, subjective swallowing function, and number of functional teeth. Structural Equation Modeling revealed that oral condition was positively correlated with nutritional status, and nutritional status was positively correlated with the World Health Organization-5 Well-Being Index. These findings suggest that oral condition may influence subjective well-being via nutritional status or social environmental factors.

Effect of oral health status and oral function on malnutrition in community-dwelling older adult dental patients: A two-year prospective cohort study.

OBJECTIVES: To survey oral status in detail and clarify the factors associated with nutritional status as evaluated by the Mini Nutritional Assessment. BACKGROUND: Malnutrition is common in older adults and increases the risk of frailty, sarcopenia, and mortality. However, few longitudinal studies have been performed to investigate the causal effect of oral status on malnutrition in detail, and the information reported in those longitudinal studies has been limited to dentition status and swallowing ability. MATERIALS AND METHODS: The participants in this prospective cohort study were patients who visited the Preventive Dentistry Clinic at Okayama University Hospital from November 2017 to January 2021. The number of teeth, periodontal condition, oral function (oral diadochokinesis, masticatory ability, number of bacteria in tongue coating, occlusal force, oral moisture, tongue pressure, swallowing function), nutritional status, the number of comorbidities, and mental health status were examined. These variables were analysed using structural equation modelling (SEM). RESULTS: The final analysis included 141 participants (40 males and 101 females; mean age, 73.5 ± 6.3 years; follow-up rate: 79.7%). The results of the SEM revealed that oral status (number of teeth present and swallowing function) was positively associated with nutritional status 2 years later. In addition, age was negatively associated with oral status. CONCLUSION: In community-dwelling older adult dental patients (age ≥60 years), oral function at baseline was associated with nutritional status two years later.

Nutrients Associated with Sleep Bruxism.

BACKGROUND: The purpose of the present research was to identify nutrients related to sleep bruxism and to establish a hypothesis regarding the relationship between sleep bruxism and nutrients. METHODS: We recruited 143 Japanese university students in 2021 and assigned them to sleep bruxism (n = 58) and non-sleep bruxism groups (n = 85), using an identical single-channel wearable electromyography device. To investigate nutrient intakes, participants answered a food frequency questionnaire based on food groups. We assessed differences in nutrient intakes between the sleep bruxism and non-sleep bruxism groups. RESULTS: Logistic regression modeling showed that sleep bruxism tended to be associated with dietary fiber (odds ratio, 0.91; 95% confidence interval, 0.83-1.00; p = 0.059). In addition, a subgroup analysis selecting students in the top and bottom quartiles of dietary fiber intake showed that students with sleep bruxism had a significantly lower dietary fiber intake (10.4 ± 4.6 g) than those without sleep bruxism (13.4 ± 6.1 g; p = 0.022). CONCLUSION: The present research showed that dietary fiber intake may be related to sleep bruxism. Therefore, we hypothesized that dietary fiber would improve sleep bruxism in young adults.

Features of the oral microbiome in Japanese elderly people with 20 or more teeth and a non-severe periodontal condition during periodontal maintenance treatment: A cross-sectional study.

Introduction: The aim of the present study was to characterize the profile and diversity of the oral microbiome of a periodontally non-severe group with ≥20 teeth in comparison with a severe periodontitis group of elderly Japanese people. Methods: A total of 50 patients who had ≥20 teeth and aged ≥60 years were recruited, and 34 participants (13 non-severe participants) were analyzed. After oral rinse (saliva after rinsing) sample collection, the V3-V4 regions of the 16S rRNA gene were sequenced to investigate microbiome composition, alpha diversity (Shannon index, Simpson index, richness, and evenness), and beta diversity using principal coordinate analysis (PCoA) based on weighted and unweighted UniFrac distances. A linear discriminant analysis effect size was calculated to identify bacterial species in the periodontally non-severe group. Results: The periodontally non-severe group showed lower alpha diversity than that of the severe periodontitis group (p <0.05); however, the beta diversities were not significantly different. A higher relative abundance of four bacterial species (Prevotella nanceiensis, Gemella sanguinis, Fusobacterium periodonticum, and Haemophilus parainfluenzae) was observed in the non-severe group than that in the severe periodontitis group. Conclusion: The oral microbiome in elderly Japanese people with ≥20 teeth and a non-severe periodontal condition was characterized by low alpha diversity and the presence of four bacterial species.

Trends in Self-Rated Oral Health and Its Associations with Oral Health Status and Oral Health Behaviors in Japanese University Students: A Cross-Sectional Study from 2011 to 2019.

Self-rated oral health (SROH) is a valid, comprehensive indicator of oral health status. The purpose of this cross-sectional study was to analyze how oral health behaviors and clinical oral status were associated with SROH and how they had changed over the course of nine years in Japanese university students. Data were obtained from 17,996 students who underwent oral examinations and completed self-questionnaires from 2011 to 2019. Oral status was assessed using the decayed and filled teeth scores, bleeding on probing (BOP), probing pocket depth, the Oral Hygiene Index-Simplified (OHI-S), oral health behaviors, and related factors. SROH improved from 2011 to 2019. The logistic regression model showed that university students who were female and had a high daily frequency of tooth brushing, no BOP, no decayed teeth, no filled teeth, and a low OHI-S score and were significantly more likely to report very good, good, or fair SROH. An interaction effect was observed between survey year and regular dental check-ups (year × regular dental check-ups). The improvement trend in SROH might be associated with changes in oral health behaviors and oral health status.

Oral Factors as Predictors of Frailty in Community-Dwelling Older People: A Prospective Cohort Study.

The purpose of this prospective cohort study was to identify predictors for frailty among possible oral factors in community-dwelling older people. Ninety-seven participants (≥60 years old) without frailty at baseline were included and assigned to either the robust or the frailty group after 2-year follow-up. The frailty was defined using the Japan Cardiovascular Health Study index. The numbers of present and functional teeth and periodontal disease severity were recorded. Bacterial counts on the dorsum of the tongue, oral moisture, tongue pressure, occlusal force, masticatory ability, and the oral diadochokinesis (ODK) rate were measured. Swallowing function, along with psychosocial status, relationships with communities and people, nutritional status, medical history, and comorbidities were evaluated using a questionnaire. The newly identified frailty group at follow-up showed significantly lower values in the number of teeth present, ODK/ta/sound and ODK/ka/sound rates, and clinical attachment level at baseline compared to the robust group. A logistic regression model showed a significantly negative association between the ODK/ta/sound rate at baseline and the incidence of frailty. Articulatory oral motor skill was found to be a predictor of frailty after two years.

Oral function, nutritional status and physical status in Japanese independent older adults.

OBJECTIVES: To clarify the associations among oral status, nutritional status and physical status in Japanese independent older adults. BACKGROUND: It is important to focus on factors affecting physical status associated with life dysfunction, long-term care and mortality. However, there are very few reports of the associations among oral status, nutritional status and physical status. MATERIALS AND METHODS: Patients who visited the Preventive Dentistry Clinic at Okayama University Hospital from November 2017 to January 2019 participated in this cross-sectional study. Number of teeth, periodontal condition and oral function were recorded. Bacteria counts in tongue dorsum, oral wettability, tongue pressure, tongue and lip movement function [oral diadochokinesis (ODK)], masticatory ability, bite force and swallowing function were measured. Nutritional status was assessed by the Mini Nutritional Assessment. Physical frailty status and Elderly Status Assessment Set were also evaluated. These variables were analysed by structural equation modelling (SEM). RESULTS: Data from 203 patients were analysed (63 males and 140 females). Patients ranged in age from 60 to 93 years. The final model of the path diagram was completed by SEM. ODK was positively associated with nutritional status, and nutritional status was negatively associated with frailty. Age was associated with ODK, nutritional status and frailty. CONCLUSION: Based on the associations among age, ODK, nutritional status and frailty, maintaining tongue movement function may contribute to good nutritional status and physical status in Japanese independent older adults.

Oral diadochokinesis is related to decline in swallowing function among community-dwelling Japanese elderly: a cross-sectional study.

BACKGROUND: Since oral organs function in the first stage of the swallowing process, it is possible that decline in swallowing function can be partly related to oral frailty. AIMS: The purpose of this study was to investigate the association between swallowing function and oral function among community-dwelling elderly Japanese and to propose cut-off values for screening of decline in swallowing function. METHODS: A total of 188 participants were included in the analysis. The number of present teeth and functioning teeth were counted. Bacteria counts in tongue coat, oral wettability, tongue pressure, oral diadochokinesis (ODK), masticatory ability and bite force were examined. Swallowing function was assessed using the 10-item Eating Assessment Tool (EAT-10). Receiver operating characteristic curves were used to determine the cut-off points of each oral function parameter. A logistic regression model was performed to determine the combination of parameters with the highest accuracy for differentiating decline in swallowing function from normal. RESULTS: Subjects with ODK /pa/ sound < 6.2 times/second had higher prevalence of swallowing problems than those with 6.2 times/second or more. EAT-10 scores of one or more were significantly related to older age (≥ 71 years old; odds ratio [OR] 4.321) and reduced ODK /pa/ sound (< 6.2 times/second; OR 2.914). CONCLUSIONS: Among community-dwelling elderly Japanese, those who were suspected of having decline in swallowing function had lower oral function than those who did not, and the cut-off values were 71 years of age and ODK /pa/ sound 6.2 times/s.

Association between Household Exposure to Secondhand Smoke and Dental Caries among Japanese Young Adults: A Cross-Sectional Study.

The long-term effects of secondhand smoke (SHS) on dental caries among Japanese young adults remain unclear. The purpose of this cross-sectional study was to evaluate whether household exposure to SHS is associated with dental caries in permanent dentition among Japanese young adults. The study sample included 1905 first-year university students (age range: 18-19 years) who answered a questionnaire and participated in oral examinations. The degree of household exposure to SHS was categorized into four levels according to the SHS duration: no experience (-), past, current SHS < 10 years, and current SHS ≥ 10 years. Dental caries are expressed as the total number of decayed, missing, and filled teeth (DMFT) score. The relationships between SHS and dental caries were determined by logistic regression analysis. DMFT scores (median (25th percentile, 75th percentile)) were significantly higher in the current SHS ≥ 10 years (median: 1.0 (0.0, 3.0)) than in the SHS-(median: 0.0 (0.0, 2.0)); p = 0.001). DMFT ≥ 1 was significantly associated with SHS ≥ 10 years (adjusted odds ratio: 1.50, 95% confidence interval: 1.20-1.87, p < 0.001). Long-term exposure to SHS (≥10 years) was associated with dental caries in permanent dentition among Japanese young adults.

Caries Increment and Salivary Microbiome during University Life: A Prospective Cohort Study.

The purpose of this 3-year prospective cohort study was to explore the relationship between an increase in dental caries and oral microbiome among Japanese university students. We analyzed 487 students who volunteered to receive oral examinations and answer baseline (2013) and follow-up (2016) questionnaires. Of these students, salivary samples were randomly collected from 55 students at follow-up and analyzed using next-generation sequencing. Students were divided into two groups: increased group (Δdecayed, missing, and filled teeth (ΔDMFT) score increased during the 3-year period) and non-increased group (ΔDMFT did not increase). Thirteen phyla, 21 classes, 32 orders, 48 families, 72 genera, and 156 species were identified. Microbial diversity in the increased group (n = 14) was similar to that in the non-increased group (n = 41). Relative abundances of the family Prevotellaceae (p = 0.007) and genera Alloprevotella (p = 0.007) and Dialister (p = 0.039) were enriched in the increased group compared with the non-increased group. Some bacterial taxonomic clades were differentially present between the two groups. These results may contribute to the development of new dental caries prevention strategies, including the development of detection kits and enlightenment activities for these bacteria.

Association between Sleep Quality and Duration and Periodontal Disease among University Students: A Cross-Sectional Study.

The purpose of this cross-sectional study was to investigate the association between sleep quality and duration, and periodontal disease among a group of young Japanese university students. First-year students (n = 1934) at Okayama University who voluntarily underwent oral health examinations were included in the analysis. Sleep quality and duration were assessed by the Japanese version of the Pittsburgh Sleep Quality Index. Dentists examined Oral Hygiene Index-Simplified (OHI-S), probing pocket depth (PPD), and percentage of sites with bleeding on probing (BOP). Periodontal disease was defined as presence of PPD ≥ 4 mm and BOP ≥ 30%. Overall, 283 (14.6%) students had periodontal disease. Poor sleep quality was observed among 372 (19.2%) students. Mean (± standard deviation) sleep duration was 7.1 ± 1.1 (hours/night). In the logistic regression analysis, periodontal disease was significantly associated with OHI-S (odds ratio [OR]: 2.30, 95% confident interval [CI]: 1.83-2.90; p < 0.001), but not sleep quality (OR: 1.09, 95% CI: 0.79-1.53; p = 0.577) or sleep duration (OR: 0.98, CI: 0.87-1.10; p = 0.717). In conclusion, sleep quality and duration were not associated with periodontal disease among this group of young Japanese university students.

Associations between sleep bruxism, sleep quality, and exposure to secondhand smoke in Japanese young adults: a cross-sectional study.

OBJECTIVE: Sleep bruxism, a major sleep disorder that causes serious harm to oral health, is considered a multifactorial disease. Sleep bruxism can be induced by smoking, which also adversely affects sleep quality. The objective of present study was to clarify the associations between sleep bruxism, sleep quality, and exposure to secondhand smoke (SHS). METHODS: To assess the prevalence of sleep bruxism, sleep quality, and SHS exposure, we conducted oral examinations and self-report questionnaires on university students in Japan. Sleep bruxism and quality were screened using the Japanese version of the Pittsburgh Sleep Quality Index (PSQI) and the third edition of the International Classification of Sleep Disorders (ICSD-3). The inclusion criteria were adults aged between 18 and 19 years, non-smokers and non-alcohol drinkers. The exclusion criteria was failing to complete the questionnaire in full. RESULTS: We analyzed a total of 1781 Japanese young adults. Young adult females who had been exposed to SHS had worse sleep quality (p = 0.019) than those who had not. Young adult female with worse sleep quality showed a higher prevalence of sleep bruxism (p = 0.034) than those with better sleep quality. Using structural equation modeling, direct associations were identified between SHS exposure and poor sleep quality (standardized coefficients, 0.153; p = 0.008) and between sleep bruxism and poor sleep quality (standardized coefficients, 0.187; p = 0.022) in young adult females. However, no association was found among young adult males. CONCLUSION: SHS exposure is indirectly associated with sleep bruxism through poor sleep quality in Japanese young adult females.

Association between intensive health guidance focusing on eating quickly and metabolic syndrome in Japanese middle-aged citizens.

PURPOSE: The purpose of this intervention study was to investigate whether intensive health guidance focusing on eating quickly can prevent metabolic syndrome (MetS) more effectively than standard routine guidance in Japanese citizens living in rural areas. METHODS: This controlled, non-randomized, intervention study analyzed 141 participants with MetS at baseline. Participants in the intervention group received health guidance focusing on eating quickly and standard health guidance about MetS in accordance with the guidelines of the Ministry of Health, Labour and Welfare in Japan, whereas participants in the control group received only standard health guidance about MetS. The primary study outcome was the prevalence of MetS at a 1-year follow-up. RESULTS: At 1-year follow-up, the prevalence of MetS in the intervention group was significantly lower than that in the control group (p = 0.003). The decreases in body weight, body mass index, waist circumference and triglycerides from baseline to 1 year were significantly greater in the intervention group than in the control group (p < 0.05). CONCLUSION: Intensive health guidance focusing on eating quickly is more effective for improving MetS than standard Japanese health guidance alone. LEVEL OF EVIDENCE: Level II, Evidence obtained from well-designed controlled trials without randomization. TRIAL REGISTRY NAME, REGISTRATION IDENTIFICATION NUMBER, AND URL FOR THE REGISTRY: UMIN, UMIN000030600, http://www.umin.ac.jp/ctr/index-j.htm.

Does Instruction of Oral Health Behavior for Workers Improve Work Performance?-Quasi-Randomized Trial.

Oral disease can cause economic loss due to impaired work performance. Therefore, improvement of oral health status and prevention of oral disease is essential among workers. The purpose of this study was to investigate whether oral health-related behavioral modification intervention influences work performance or improves oral health behavior and oral health status among Japanese workers. We quasi-randomly separated participants into the intervention group or the control group at baseline. The intervention group received intensive oral health instruction at baseline and a self-assessment every three months. Both groups received oral examinations and answered the self-questionnaire at baseline and at one-year follow-up. At follow-up, the prevalence of subjects who use fluoride toothpastes and interdental brushes/dental floss were significantly higher in the intervention group than in the control group. Three variables (tooth brushing in workplace, using fluoride toothpaste, and experience of receiving tooth brushing instruction in a dental clinic) showed significant improvement only in the intervention group. On the other hand, work performance and oral status did not significantly change in either group. Our intensive oral health-related behavioral modification intervention improved oral health behavior, but neither work performance nor oral status, among Japanese workers.