Association of health behaviors, dietary habits, and oral health with weight gain after 20 years of age in community-dwelling Japanese individuals aged 40 years and older: a cross-sectional study.

OBJECTIVES: This cross-sectional study investigated the factors associated with weight gain ≥ 10 kg after 20 years of age in the general Japanese population, with a focus on the number of teeth. MATERIALS AND METHODS: We included individuals aged ≥ 40 years from Yamagata prefecture, Japan from 2017-2021. A postal survey was conducted using a self-administered questionnaire; 5,940 participants were included in the final analysis. The questionnaire included items on lifestyle factors, medical history, physical and mental conditions, oral health, and dietary intake. A multivariate logistic regression analysis was used to identify independent associations between weight gain ≥ 10 kg after 20 years of age and various parameters; adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were estimated. RESULTS: Less than 20 teeth, male sex, drinking habit frequency, eating very fast or fast, and a higher frequency of eating-away-from-home were significant factors associated with weight gain ≥ 10 kg after 20 years of age; individuals with < 20 versus > 20 teeth exhibited a 1.35-fold higher OR (95% CI 1.15-1.59; p < 0.01). CONCLUSIONS: Our results suggest that having < 20 teeth may affect weight gain ≥ 10 kg after 20 years of age. However, owing to the cross-sectional study design, causality could not be determined. Therefore, maintaining healthy lifestyle behaviors to avoid tooth loss may also affect weight gain ≥ 10 kg after 20 years of age. CLINICAL RELEVANCE: Having < 20 teeth has the potential to affect long-term weight gain after 20 years of age.

High Parity Is an Independent Risk Factor for Tooth Loss in Women: A Community-Based Takahata Study in Japan.

Risk factors for tooth loss have been widely examined previously. However, no previous study has comprehensively investigated the risk factors, including lifestyle-related specific factors (parity, oral health habits, and socioeconomic status), for fewer than 20 teeth among women in the general population in Japan. This cross-sectional study explored the association of these risk factors, especially parity, with having fewer than 20 teeth among Japanese women. A self-reported questionnaire including items on lifestyle-related risk factors (parity, oral health, diet [e.g., alcohol and sucrose consumption]) and socioeconomic status was sent by post to female residents (age ≥ 40 years) of Takahata town, Yamagata Prefecture, in 2005. Multivariate logistic regression analysis including 3,854 eligible participants was performed to investigate the association between various factors (including parity) and having fewer than 20 teeth. The results indicated that, compared with nulliparous women, women with two, three, and four completed pregnancies had 2.485-, 2.844-, and 4.305-fold increased risk of having fewer than 20 teeth, respectively. Our study is the largest-scale study of the general female population in Japan and the first study to comprehensively investigate risk factors (parity, oral health status, and socioeconomic status) for fewer than 20 teeth. We thus found that higher parity, especially, two or more, was independent risk factors for having less than 20 teeth among Japanese women. In conclusion, the present study emphasizes the importance of good oral health habits in women, especially, during pregnancy and in the postpartum period, to maintain 20 or more teeth.

Association between presence of 20 or more natural teeth and all-cause, cancer-related, and cardiovascular disease-related mortality: Yamagata (Takahata) prospective observational study.

BACKGROUND: Several studies have surveyed the relationship between the presence of ≥ 20 natural teeth and mortality. However, very few have evaluated this association over a long-term follow-up of more than ten years within a large population in Japan. This study aimed to prospectively confirm the associations between mortality and the presence of ≥ 20 natural teeth within a community-based population in Japan. METHODS: A prospective observational study including 2208 participants aged ≥ 40 years was conducted in Takahata Town, Japan, between May 2005 and December 2016. All participants answered a self-administered questionnaire to provide their background characteristics, including their number of teeth. The participants were classified into two categories based on their self-reported number of teeth (< 20 and ≥ 20 teeth). Hazard ratios (HR) and 95% confidence intervals (CI) were calculated using Cox proportional-hazards regression model to assess risk factors for all-cause, cancer-, and cardiovascular disease-related mortality. RESULTS: The total follow-up period was 131.4 ± 24.1 months (mean ± SD). After adjusting for covariates, the risk of all-cause mortality was significantly higher in the group with < 20 teeth than in those with ≥ 20 teeth (HR = 1.604, 95% CI 1.007-2.555, p = 0.047). However, the risk of cancer- and cardiovascular disease-related mortalities was not statistically significant between the two groups. CONCLUSION: In this study, participants with < 20 teeth had a significantly higher risk of all-cause mortality, although the difference was borderline significant. These results emphasize the importance of having ≥ 20 natural teeth for a healthy life expectancy.

Risk factors for tooth loss in community-dwelling Japanese aged 40 years and older: the Yamagata (Takahata) study.

OBJECTIVES: The aim of the present study was to investigate comprehensively the risk factors, including some lifestyle-associated factors, oral health habits, and socioeconomic status, for having less than 20 teeth in cross-sectional study in the general population of Japan. MATERIALS AND METHODS: The survey population was the general population of individuals aged greater than or equal to 40 years in Takahata town, Japan in 2005. A postal survey with a self-administered questionnaire was distributed, and 7542 participants were entered into the final statistical analysis. The self-administered questionnaire contained items regarding some lifestyle-associated factors, oral health, and dietary intake, including alcohol and sucrose consumption. To confirm the independent association between the number of teeth and several parameters, a multivariate logistic regression analysis was used to estimate the adjusted odds ratios (ORs) and 95% confidence intervals (95% CIs). RESULTS: A low educational status, no dental check-ups, low frequency of brushing, older age, and smoking habit were independent risk factors for less than 20 teeth. A low educational status was a particularly significant risk factor for less than 20 teeth (OR = 1.352, 95% CI = 1.125-1.624). CONCLUSION: These results emphasize the importance of good oral health habits, such as frequent tooth brushing, routine dental check-ups, and no smoking, and indicate that more appropriate and compulsory education regarding oral health is needed to lessen the education level-derived differences in oral health. CLINICAL RELEVANCE: Poor oral health habits and low educational status are the independent risk factors for having less than 20 teeth.

Fewer teeth are a risk factor for being underweight in community-dwelling Japanese aged 40 years and older: The Yamagata (Takahata) Study.

OBJECTIVE: The aim of the present study was to investigate comprehensively, the risk factors for underweight in cross-sectional study in the general population of Japan. METHODS: The survey population was the general population of individuals aged >40 years in Takahata town, Japan in 2005. A postal survey in the form of a self-administered questionnaire was distributed, and 6084 individuals were entered into the final statistical analysis. The self-administered questionnaire contained items regarding lifestyle, oral health status, socio-economic status and dietary intake. To examine the independent relationships between an underweight status and several parameters, a multivariate logistic regression analysis was used to estimate adjusted odds ratios (ORs). RESULTS: The number of teeth, age, alcohol consumption, hypertension, spousal status, smoking habit, appetite, body weight at 20 years of age, habit of going out and physical activity were independently associated with an underweight status compared with the normal weight group. Individuals with fewer than 10 teeth were especially more likely to be underweight than individuals with more than 20 teeth (OR = 1.956, 95% CI = 1.261-3.035). CONCLUSION: This study showed an independent association between the number of teeth and an underweight status, indicating that fewer teeth can increase the risk of being underweight.

Associations between subjective well-being, number of teeth, and self-rated mastication in Japanese adults: A cross-sectional study.

This cross-sectional study aimed to investigate the risk factors for low levels of subjective well-being (SWB) in the general population of Japan, specifically, the impact of the number of teeth and self-rated mastication. The surveyed population consisted of individuals aged between 40 and 79 years from Yamagata prefecture, Japan. A postal self-administered questionnaire survey of respondents lifestyles, medical history, oral health, and dietary intake, was conducted from 2017 to 2021. We included 6846 participants to confirm the independent associations between SWB and several parameters using multivariate ordinal logistic regression analysis to estimate adjusted odds ratios and 95% confidence intervals. Individuals with < 20 teeth and poor mastication ability had a 1.3-fold risk for low levels of SWB compared with individuals with ≥ 20 teeth with good mastication ability (adjusted odds ratios = 1.300, 95% confidence intervals = 1.043-1.621, P = .020). There were no differences between individuals with good mastication ability, regardless of the number of remaining teeth. Our study emphasizes not only the importance of having ≥ 20 teeth and good mastication ability for high levels of SWB but also the importance of restoring mastication ability using some form of prosthesis, to facilitate a high level of SWB when the number of remaining teeth is < 20.

Association of the number of teeth and self-rated mastication with self-rated health in community-dwelling Japanese aged 40 years and older: the Yamagata cohort study.

Self-rated health (SRH) is a predictive factor for health-related prognoses such as mortality. This study aimed to comprehensively investigate the risk factors for poor SRH in the general population of Japan, focusing on the combination of the number of teeth and self-rated mastication. Individuals aged at least 40 years in Yamagata Prefecture, Japan, were surveyed from 2017 to 2021. The participants answered a self-administered postal survey on lifestyle factors, medical history, physical and mental conditions, oral health, and dietary intake, and 6739 participants were included. Multivariate logistic regression analysis showed that individuals with less than 20 teeth and who bite tightly on one side or neither side were at a 1.422- and 1.952-fold significantly higher risk, respectively, of poor SRH than individuals with at least 20 teeth and who bite tightly on both sides. Moreover, individuals who had less than 20 teeth but could bite tightly on both sides did not have a significant risk compared to those who had at least 20 teeth and could bite tightly on both sides. Regarding individuals with more than 20 teeth, there was no difference between those who could and could not bite tightly on both sides, although the odds ratios for poor SRH tended to increase for those who could bite on one side or neither side. Our results emphasize the importance of having at least 20 teeth without periodontal disease and oral rehabilitation using a type of prosthesis for SRH, even with less than 20 teeth.

Identification of Salivary Proteomic Biomarkers for Oral Cancer Screening.

BACKGROUND/AIM: The current study aimed to identify biomarkers for differentiating between patients with oral cancer (OC) and healthy controls (HCs) on the basis of the comprehensive proteomic analyses of saliva samples by using liquid chromatography-mass spectrometry (LC-MS/MS). PATIENTS AND METHODS: Unstimulated saliva samples were collected from 39 patients with OC and from 31 HCs. Proteins in the saliva were comprehensively analyzed using LC-MS/MS. To differentiate between patients with OC and HCs, a multiple logistic regression model was developed for evaluating the discriminatory ability of a combination of multiple markers. RESULTS: A total of 23 proteins were significantly differentially expressed between the patients with OC and the HCs. Six out of the 23 proteins, namely α-2-macroglobulin-like protein 1, cornulin, hemoglobin subunit ß, Ig k chain V-II region Vk167, kininogen-1 and transmembrane protease serine 11D, were selected using the forward-selection method and applied to the multiple logistic regression model. The area under the curve for discriminating between patients with OC and HCs was 0.957 when the combination of the six metabolites was used (95% confidence interval=0.915-0.998; p<0.001). Furthermore, these candidate proteins did not show a stage-specific difference. CONCLUSION: The results of the current study showed that six salivary proteins are potential non-invasive biomarkers for OC screening.

A case of myeloid sarcoma of the mandibular gingiva as extramedullary relapse of acute myeloid leukemia.

PURPOSE: Myeloid sarcoma (MS) is defined as a tumorous mass of myeloblasts or immature myeloid cells involving an extramedullary anatomic site. MS occurs in 3 to 8% of patients with acute myeloid leukemia. The overwhelming majority of MS occurs in the skin, bones, and gastrointestinal tract; intraoral MS (IMS) is extremely rare. METHODS: We describe a case of MS of the mandibular gingiva in a patient with acute myeloid leukemia that was in remission. We also present a review of the English and Japanese literature with a special focus on the management and prognosis of intraoral MS. RESULTS: The patient was discharged while in remission 8 months after the initial examination. CONCLUSION: The prognosis of IMS is extremely poor in general, and a diagnostic delay can prevent adequate therapy by hematologists and oncologists. All dental clinicians must keep the possibility of IMS in mind and carefully examine all patients with AML.

Tooth Loss-associated Cognitive Impairment in the Elderly: A Community-based Study in Japan.

Objective Dementia is a major cause of disruption for a healthy life expectancy in Japan. It has been suggested that the number of teeth is a modifiable risk factor for cognitive impairment and dementia. We therefore examined the possible association between the cognitive function and the number of natural and artificial teeth in community-dwelling Japanese elderly individuals. Methods Among the participants in our prospective, community-based study, 210 elderly individuals (103 men and 107 women; 78.1±4.9 years; mean age±standard deviation) underwent both dental examinations and a Mini-Mental State Examination (MMSE), as well as various medical checkups, in 2016 and 2017. Results The number of natural teeth was significantly associated with an individual's MMSE score. The percentage of cognitively normal subjects (MMSE scores: 27-30) decreased significantly with a decrease in the number of natural teeth. Among the MMSE items, the calculation ability was significantly and independently associated with the number of natural teeth. Regression was calculated as the predicted score of MMSE =21+0.3× (years of schooling) +0.1× (number of natural teeth). Among individuals with 19 or fewer natural teeth, those who had a total of 20 teeth or more, including both natural and artificial teeth, had significantly higher MMSE scores than those who had 19 or fewer natural and artificial teeth combined. Conclusion The number of natural teeth was significantly associated with the cognitive function, especially the calculation ability, and the use of artificial teeth was associated with the preservation of the cognitive function in community-dwelling elderly individuals.