Akihisa Mitani

Background: Toothbrushing is important for maintaining oral health and preventing periodontal disease. However, the association between toothbrushing and systemic diseases remains unclear in adolescence. In this study, the association between dental self-care (frequency and duration of toothbrushing) and systemic diseases/disorders in adolescents was examined. Methods: We conducted a retrospective review of mandatory medical questionnaires administered during legally mandated freshman medical checkups between 2017 and 2019 at the University of Tokyo, Japan. Out of 9376 total responses, 9098 cases involving individuals under the age of 20 were included in the analysis. Respondents were classified into three groups based on their daily toothbrushing frequency: “1 time or less”, “twice”, and “3 times or more”. For the duration of each toothbrushing session, they were classified into three groups: “1 min or less”, “2–3 min”, and “4 min or more”. A statistical analysis was performed by Pearson’s χ² test and multinomial logistic regression analysis. Results: Regarding frequency of daily toothbrushing: The χ² test showed no significant relationship between frequency of toothbrushing and 17 systemic diseases/disorders. A multivariate analysis found that gingival bleeding and sex were independent factors. The risk of gingival bleeding decreased dramatically with increased frequency of toothbrushing (odds ratio (OR): 0.428; 95% confidence interval (CI), 0.366–0.501; p < 0.001). Regarding the amount of time spent on toothbrushing: The χ² test showed atopic dermatitis and arrhythmia were significantly associated with the duration of toothbrushing (p = 0.032 and p = 0.016, respectively). In the multivariate analysis, atopic dermatitis, gingival bleeding, and sex were independent factors regarding the duration of toothbrushing; longer brushing time was associated with a lower risk of atopic dermatitis (OR: 0.731, 95% CI: 0.578–0.924, p = 0.009) and a lower risk of gingival bleeding (OR: 0.643, 95% CI: 0.567–0.729, p < 0.001). Conclusions: Dental self-care was most strongly associated with gingival bleeding, while the risk of atopic dermatitis was found to increase with shorter toothbrushing times. The results suggest that dental self-care during adolescence is important not only for oral health but also for general health.

A growing body of evidence suggests that the effects of poor oral hygiene extend beyond the oral cavity and are associated with a variety of systemic diseases, including asthma. Asthma, which results in symptoms of cough, wheezing, and dyspnoea, and is characterized by airflow limitation with variability and (partial or complete) reversibility, is amongst the most prevalent respiratory diseases with approximately 262 million patients worldwide, and its prevalence and disease burden is on the increase. While asthma can occur at a young age, it can also develop later in life and affects a variety of age groups. Both of these diseases have a chronic course, and various researchers have suggested a link between the two. In this article, we aim to provide a literature review focusing on the association between the two diseases. The results demonstrate that medications (primarily, inhaler medicine), hypoxia induced by asthma, and the breathing behaviour of patients potentially trigger periodontal disease. In contrast, oral periodontopathogenic microorganisms and the inflammatory mediators produced by them may be involved in the onset and/or exacerbation of asthma. Common contributing factors, such as smoking, gastro-oesophageal reflux, and type-2 inflammation, should also be considered when evaluating the relationship between the two diseases.

The prevalence of chronic obstructive pulmonary disease (COPD) is increasing worldwide and is currently the third leading cause of death globally. The long-term inhalation of toxic substances, mainly cigarette smoke, deteriorates pulmonary function over time, resulting in the development of COPD in adulthood. Periodontal disease is an inflammatory condition that affects most adults and is caused by the bacteria within dental plaque. These bacteria dissolve the gums around the teeth and the bone that supports them, ultimately leading to tooth loss. Periodontal disease and COPD share common risk factors, such as aging and smoking. Other similarities include local chronic inflammation and links with the onset and progression of systemic diseases such as ischemic heart disease and diabetes mellitus. Understanding whether interventions for periodontal disease improve the disease trajectory of COPD (and vice versa) is important, given our rapidly aging society. This review focuses on the putative relationship between COPD and periodontal disease while exploring current evidence and future research directions.

Inhaler devices play an important role in the management of obstructive lung diseases including asthma, chronic obstructive pulmonary disease (COPD), and asthma–COPD overlap. Some of these patients show suboptimal inhaler techniques; however, time for inhaler instruction by pharmacists is limited in daily clinical practice. Therefore, sufficient education regarding inhaler device handling should be provided within a limited time frame. The current study aimed to investigate the instruction methods provided by community pharmacists and their influence on inhaler device handling techniques in outpatient clinical care settings. We retrospectively collected the data of outpatients with obstructive lung diseases who were referred to our hospital and who underwent inhalation technique assessments conducted by community pharmacists. The prevalence of handling errors, clinical characteristics of patients, and instruction methods were analyzed. In total, 138 patients (170 devices) were included in this study. Approximately 70.0% of patients received verbal explanations combined with leaflets about inhaler instructions. In a device-based analysis, 63 (37.1%) of 170 devices had at least one technical error and 18 (10.6%) of the devices had critical errors. Patients without critical errors received practical demonstration instructions from pharmacists combined with leaflets and verbal explanations more frequently than those with critical errors (22.8 vs. 0%, p < 0.01). This study revealed that patients with obstructive lung diseases commonly present with inhaler device handling errors and critical errors were observed with non-negligible frequency in daily practice in Japan. Combined instruction with leaflet, verbal explanation, and pharmacist demonstration may be effective in improving proper inhaler treatment.

In the near future, Japan is entering a super-aging society that will be called the age of 100 years of life

Oral diseases such as dental caries and periodontal disease are reported to be associated with various systemic diseases such as heart disease, respiratory disease, diabetes, rheumatism, and metabolic syndrome, thus increasing the importance of prevention and early treatment

Spirometry is a standard method for assessing lung function. However, its use is challenging in some patients, and it has limitations such as risk of infection and inability to assess regional chest wall motion. A three-dimensional motion capture system using the one-pitch phase analysis (MCO) method can facilitate high precision measurement of moving objects in real-time in a non-contacting manner. In this study, the MCO method was applied to examine thoraco-abdominal (TA) wall motion for assessing pulmonary function. We recruited 48 male participants, and all underwent spirometry and chest wall motion measurement with the MCO method. A significant positive correlation was observed between the vital capacity (Spearman’s ρ = 0.68, p < 0.0001), forced vital capacity (Spearman’s ρ = 0.62, p < 0.0001), and tidal volume (Spearman’s ρ = 0.61, p < 0.0001) of spirometry and the counterpart parameters of MCO method. Moreover, the MCO method could detect regional rib cage and abdomen compartment contributions and could assess TA asynchrony, indicating almost complete synchronous movement (phase angle for each compartment: − 5.05° to 3.86°). These findings suggest that this technique could examine chest wall motion, and may be effective in analyzing chest wall volume changes and pulmonary function.

Background: Oral diseases are associated with various systemic disorders. Our previous research revealed new insights into the close relationship between occlusal disorder (functional disorder) and systemic disorders (allergic rhinitis, asthma, and arrhythmia) in late adolescence. Here, we investigated whether there was an association between the awareness of teeth-alignment disorder (morphological disorder) and common systemic disorders. Subjects and Methods: We retrospectively reviewed the data of the mandatory medical questionnaire that is required for the freshman medical checkup in Japan. We collected the data of all students who completed the questionnaire between April 2017 and April 2019. The data were analyzed using the χ² test, and a multivariate analysis was performed with a binomial logistic regression model. Results: The subjects were 8903 students aged 17–19 who had no awareness of occlusal disorder. The rate of awareness of teeth-alignment disorder was 20.43% (1819 of 8903 eligible subjects), and the aware students had significantly greater rates of gum bleeding (p < 0.001), pollinosis (n = 0.007), and atopic dermatitis (n = 0.042). The multivariate analysis revealed significant rates of gum bleeding (odds ratio (OR) 1.540, 95% confidence interval (CI): 1.386–1.711, p < 0.001), pollinosis (OR 1.197, 95% CI: 1.040–1.378, p = 0.012), and female gender (OR 1.141, 95% CI: 1.002–1.299, p = 0.046) among the students with awareness of teeth-alignment disorder. Conclusion: We identified close associations between the awareness of teeth-alignment disorder and both gum bleeding and pollinosis in a late-adolescent population. The systemic disorders that are targeted by teeth-alignment disorder were found to be different from those targeted by occlusal disorder.

Background: Oral infectious diseases are typified by dental caries and periodontal diseases and are known to be associated with various systemic diseases. However, clear associations between occlusal disorders and systemic diseases have not yet been established. We investigated the association between an awareness of malocclusion and common diseases in late adolescence. Methods: We retrospectively reviewed the data of mandatory medical questionnaires that are a legal requirement of the freshman medical checkup. We collected the data of all the students who completed the questionnaires between April 2017 and 2019. The data were analyzed using the χ² test and multivariate analysis was performed with a binomial logistic regression model. Results: The subjects were 9098 students aged 17–19 (mean age 18.3 years). The rate of awareness of malocclusion was 2.14% (195 out of 9098 eligible subjects; 160 males and 35 females). These students had significantly greater rates of allergic rhinitis, asthma, and arrhythmia (p < 0.001). Multivariate analysis revealed significant rates of allergic rhinitis (odds ratio [OR] 2.184, 95% confidence interval [CI]: 1.468–3.250, p < 0.001), asthma (OR 1.843, 95%CI: 1.153–2.945, p = 0.011), and arrhythmia (OR 2.809, 95%CI: 1.083–7.288, p = 0.034) among students with an awareness of malocclusion. Conclusion: We identified close associations between an awareness of malocclusion and systemic diseases including allergic rhinitis, asthma, and arrhythmia in the late adolescent population. These results reinforce the associations between malocclusion and allergic rhinitis and asthma, as well as providing novel insight into the association of malocclusion and arrhythmia. However, further research is necessary to confirm the associations and explore the mechanisms underlying these associations.

Background: Epidemiologic studies provide broad-based evidence that males are at greater risk of severe periodontal diseases than females. Our recent findings further revealed that male gender was an independent risk factor for gingival bleeding in late adolescents in Japan. Gingival health status has been reported to be affected by oral hygiene behavior. However, gender difference in this regard has not yet been clarified. Methods: We conducted a retrospective review of mandatory medical questionnaires administered as part of a legally required freshman medical checkup between April 2017 and 2019 at the University of Tokyo. Results: Among a total of 9376 sets of responses, chosen subjects were 9098 students aged 17–19. For frequency of daily brushing, males brushed less frequently than females (p < 0.001): 1 time or less (male: 22.9%, female: 11.2%), twice (65.0%, 69.2%), 3 times or more (12.1%, 19.6%). For the duration of brushing each time, males brushed for a shorter period of time than females (p = 0.005): 1 min or less (male: 17.2%, female: 14.1%), 2–3 min (46.9%, 49.2%), 4 min or more (35.9%, 36.7%). (1) Male gender, (2) lower frequency of daily brushing and (3) shorter duration of brushing each time, were significantly associated with the presence of gingival bleeding (p < 0.001 for all). Multivariate regression analysis showed that: (1) male gender (odds ratio 1.29, 95% confidence interval 1.15–1.44); (2) frequency of daily brushing: 1 time or less (2.36, 2.02–2.76), twice (1.45, 1.27–1.67); and (3) brushing duration each time: 1 min or less (1.57, 1.39–1.78), 2–3 min (1.26, 1.14–1.39), were independent risk factors for gingival bleeding (p < 0.001 for all). Conclusions: Males showed poorer oral hygiene behavior than females in late adolescents in Japan. Male gender was an independent risk factor for gingival bleeding, as well as poor oral hygiene behavior.