Relationship of Routine Inadequate Sleep Duration and Periodontitis in a Nationally Representative Sample

Sleep Duration and Risk of Periodontitis-A Systematic Review and Meta-Analysis

Periodontitis, with a high prevalence in the whole population, is the main cause of tooth loss. Some studies have revealed that sleep duration may be related to periodontitis, however, the opinions are not consistent. This meta-analysis was carried out to study the potential relationship between sleep duration and periodontitis. A search of relevant articles was conducted on Embase, PubMed, Cochrane Library, and Web of Science. Papers published until the end of November 2022 reporting associations between sleep duration and periodontitis were considered. The pooled odds ratio (OR) with a 95% confidence interval (CI) was calculated to assess the association. Software STATA 14.0 was employed to conduct this analysis. A total of 11 cross-sectional studies were included. Our study showed neither short sleep duration (SSD) nor long sleep duration (LSD) were associated with periodontitis (SSD: OR = 1.04, 95% CI: 0.83, 1.29; LSD: OR = 1.12, 95% CI: 0.94, 1.23), while higher prevalence was observed when sleep duration ≤5 h (OR = 1.41, 95% CI: 1.33, 1.51). In addition, both SSD and LSD were not associated with severe periodontitis (SSD: OR = 0.94, 95% CI: 0.75, 1.16; LSD: OR = 1.19, 95% CI: 0.80, 1.76). In conclusion, the present review indicated that too little sleep duration (≤5 h) significantly increased the risk of periodontitis. However, the evidence is limited due to cross-sectional design of most studies, Hence longitudinal studies should be conducted to support this finding.

Association of Sleep Duration with Tooth Loss and Periodontitis: Insights from the National Health and Nutrition Examination Surveys (2005-2020)

OBJECTIVE

Sleep disorders such as insomnia, apnea, and restless leg syndrome can negatively affect a person's overall health and may cause hypertension, heart failure, and coronary heart disease. Likewise, periodontitis, a gum disease, can lead to both physical and psychological health issues, exerting a considerable effect on one's overall well-being-periodontitis stands as a primary cause of tooth loss. Nevertheless, there has been insufficient research on the correlation between the amount of sleep individuals get and the occurrence of periodontitis/tooth loss among Americans. Therefore, this study aimed to assess the influence of sleep length on periodontitis in the American population.

METHODS

Periodontitis severity was classified (none, mild, moderate, and severe) using American Periodontal Association criteria. Sleep duration was assessed by self-reported data and categorized into three groups (deficient, adequate, and excessive). Tooth loss was assessed by the oral examination. To establish a connection between the duration of sleep and periodontitis/tooth loss, a weighted multivariable logistic regression analysis was employed. A GAM analysis and smooth curve fitting assessment were conducted to identify non-linear relationships. Subgroup, interaction, and mediation analyses were also performed.

RESULTS

The prevalence of tooth loss was significantly high, affecting 96.4% of the individuals, whereas 46.6% of the study sample experienced moderate to severe periodontitis. The average age of participants was 52.7 years. After adjusting for potential confounding factors, the analysis of weighted multivariable logistic regression revealed a significant association between sleep insufficiency and moderate/severe periodontitis (OR 1.15, 95% CI 1.01-1.30, P = 0.0298), as well as tooth loss (OR 1.16, 95% CI 1.01-1.33, P = 0.0371). Additionally, the research showed a correlation between the length of sleep and periodontitis that followed a U-shaped pattern. In addition, the analysis of mediation revealed that high blood pressure explained 7.0% (95% CI 4.0% to 12.9%; P < 0.0001) of the link between the amount of sleep and the likelihood of losing teeth.

CONCLUSION

Sleep duration was independently correlated with moderate/severe periodontitis/tooth loss and had a non-linear relationship.

Is insufficient sleep duration a risk indicator for periodontal disease? A systematic review

OBJECTIVES

In this study, we conducted a systematic review and meta-analysis to assess whether people who achieved <7 h of sleep were more likely to develop periodontal disease (PD).

SOURCES

We executed electronic searches in the PubMed, EMBASE and Cochrane Library, as well as a manual search of articles published by leading journals in related fields, for observational studies, published in English from 1 January 1966 to 31 March 2021.which evaluated the relationship between sleep duration and PD. The Agency for Healthcare Research and Quality (AHRQ) quality evaluation scale was used for the cross-sectional studies, and the random effects model was used to summarize the effect sizes in the included studies with a 95% confidence interval (CI).

RESULTS

A total of six cross-sectional studies met the inclusion criteria, totaling 107,777 participants, of which 69,773 had PD. The results of the present indicated that shorter sleep duration (<7 h) is significantly associated with PD (Odd ratio [OR], 1.19; 95% CI, 1.16-1.23; p < 0.001; I² , 0.0%, I² interval, 0%-75%). The strength of the sensitivity analysis and cumulative meta-analysis confirmed the reliability of the results.

CONCLUSION

Although the inclusion of only six studies makes it difficult to explore whether there is a publication bias, we found that insufficient sleep duration was closely related to PD, and we therefore speculated that getting enough sleep may help prevent PD.

Association between skull bone mineral density and periodontitis: Using the National Health and Nutrition Examination Survey (2011-2014)

BACKGROUND AND OBJECTIVE

Bone mineral density (BMD) and periodontitis have been the subject of many studies. However, the relationship between skull (including mandible) BMD and periodontitis has not been extensively studied. An objective of this cross-sectional study was to examine the relationship between skull BMD and periodontitis using data from the National Health and Nutrition Examination Surveys (NHANES) for 2011-2012 and 2013-2014.

MATERIALS AND METHODS

From NHANES 2011-2014, 3802 participants aged 30-59 were selected. We divided the skull BMD level into quartiles to check the distribution of variables. Periodontitis was defined by the Centers for Disease Control and Prevention (CDC) and the American Association of Periodontology (AAP) in 2012. Multivariate logical regression analysis was used to explore the independent relationship between skull BMD and periodontitis. The generalized additive model (GAM), smooth curve fitting (penalty spline) and threshold effect analysis was used to evaluate dose-response relationship between skull BMD and periodontitis and the potential nonlinear relationship between skull BMD and periodontitis. Finally, subgroup analysis and interaction test were conducted to determine the role of covariates between skull BMD and periodontitis.

RESULTS

The overall average skull BMD of 3802 participants was 2.24g/cm2, the average age was 43.94 years, and the prevalence of periodontitis was 41.03%. In the fully adjusted logistic regression model, skull BMD and periodontitis showed an independent negative correlation (OR 0.73, 95% CI 0.59-0.90, P = 0.0032) and a linear relationship. Compared with the lowest quartile array (Q1:1.22-1.98) of skull BMD, the highest quartile array(Q4: 2.47-3.79) had a significantly lower risk of periodontitis (OR 0.70,95% CI 0.56-0.87, P = 0.0014). Subgroup analysis showed a highly consistent negative correlation between skull BMD and periodontitis. In the interaction test, people with moderate poverty income ratio (1.57-3.62) and those who had more than 12 alcohol drinks in the past year had a lower risk of periodontitis.

CONCLUSIONS

This result suggested that periodontal disease can be related to low skull BMD, for those people, oral hygiene and health care should be more closely monitored. Validation of our findings will require further research.

Are periodontal diseases associated with sleep duration or sleep quality? A systematic review

OBJECTIVES

This study aimed to systematically review the associations between periodontal diseases/tooth loss and sleep duration/quality.

MATERIAL AND METHODS

PubMed, Scopus, and Embase databases were searched (up to May 2021) to identify studies that assessed the association between periodontal diseases or number of teeth with sleep quality and sleep duration. Two researchers independently selected the studies and extracted the data. Considering the high heterogeneity among the included studies, meta-analysis was deemed unviable. Results are presented descriptively for sleep quality (studies that have used PSQI), self-reported sleep hours, and other tools that assessed sleep patterns.

RESULTS

Twenty studies (16 cross-sectional, two case-control, and two cohort) were included. Eight studies used the Pittsburgh Sleep Quality Index (PSQI) to assess quality of sleep. Six of these studies demonstrated that individuals with worse periodontal conditions demonstrated poorer sleep quality. However, most of the included studies that performed adjusted analysis showed no statistically significant association between self-reported hours of sleep and periodontitis. The mean number of present teeth was assessed in four studies; three of them demonstrated lower numbers of present teeth in individuals with inadequate sleep.

CONCLUSION

The literature shows conflicting results for the association between sleep hours and periodontitis. However, inadequate sleep may be associated with lower number of present teeth and periodontal diseases. Further studies are necessary in order to confirm these results.

Sleep time and duration is associated with periodontitis in a representative sample of Koreans

BACKGROUND

So far, studies on the association between sleep and periodontitis have shown conflicting results. This study assessed the association among sleep duration, sleep time, and periodontitis among a nationally representative Korean population and the mediation effect of WBC.

METHODS

We analyzed data from the Seventh Korean National Health and Nutrition Examination Survey (KNHANES VII) collected from 2016 to 2018. With the screenings by age (45 to 64), edentate, and the adequacy of information provided, the analysis was confined to a selected group of respondents of 4407 with measurements for the sleep survey and periodontal health status out of total 24,269. Periodontitis was defined according to the World Health Organization's community periodontal index (CPI) code greater than or equal to three, and severe periodontitis was defined as CPI code 4. Multivariable logistic regression analysis was used to test the association between sleep and periodontitis controlling the confounding factors.

RESULTS

Those who went to bed during the daytime were associated with periodontitis (OR = 1.49, 95% confidence interval [CI]: 1.07 to 2.07). In a combined sleep time and duration model, those who went to bed at night with a sleep duration of 9 hours or more were associated with periodontitis (OR = 1.69, 95% CI: 1.04 to 2.77) and severe periodontitis (OR = 1.88, 95% CI: 1.02-3.45). WBC count had the highest impact on the association between sleep time and periodontitis.

CONCLUSIONS

Our findings suggest that an extra-long sleep duration and going to bed during the daytime are associated with periodontitis.

Association between sleep habits and symptoms of oral disease in adolescents: the 2017 Korea Youth Risk Behavior Web-based Survey

BACKGROUND

This cross-sectional study aimed to examine the relationship between sleep habits and oral disease symptoms in adolescents.

METHODS

Among 62,276 adolescents who participated in the 13th Korea Youth Risk Behavior Web-based Survey (2017), we selected a total of 54,766 adolescents (age, 12-18 years; male, 49.9%) for the final analysis, after excluding those who did not report their sleep duration. The 13th Korea Youth Risk Behavior Web-based Survey data were obtained from a stratified, multistage, clustered sample. Independent variables included general characteristics, oral health behavior, sleep types, sleep duration, and sleep quality; dependent variables comprised oral disease symptoms. Sleep was categorized according to bedtime astype A (bedtime < 1 a.m.) and type B (bedtime ≥ 1 a.m.). Data were analyzed using logistic regression analysis. Statistical significance was set at p < 0.05.

RESULTS

After adjusting for all covariates, adolescents with type A sleep had a higher risk of toothache on chewing (OR = 1.08, 95% CI 1.02-1.15) than adolescents with type B. Adolescents who slept for 6 h or less each night had a higher risk of pain in the tongue and buccal mucosa (OR = 1.35, 95% CI 1.18-1.54), gingival pain, and bleeding (OR = 1.31, 95% CI 1.19-1.45) than those who slept for more than 8 h. Adolescents with low quality of sleep had a higher risk of toothache or throbbing (OR = 1.70, 95% CI 1.60-1.81), toothache on chewing (OR = 1.73, 95% CI 1.65-1.82), and halitosis (OR = 1.51, 95% CI 1.41-1.59) than those with high quality of sleep.

CONCLUSIONS

Our findings indicate that some oral symptoms are related to sleep duration and quality. It is essential to inculcate good sleeping habits in adolescents by emphasizing the effects of inadequate sleep duration and quality.

Association of Insufficient or Excess Sleep with Type 2 Diabetes Mellitus in the Presence of Periodontitis

We aimed to investigate the effects of sleep duration on impaired fasting glucose and diabetes in Korean adults with periodontal disease. This cross-sectional study was performed using data for 10,465 subjects aged >19 years who completed the periodontal examination and questionnaires in the Sixth Korea National Health and Nutrition Examination Survey (2013-2015). The effect of sleep was confirmed by a complex-sample multinomial logistic regression analysis. Confounding variables were age, sex, household income, education level, smoking status, and sleep duration. Of all participants, 25.7% had periodontitis, of which 28.6% had fasting serum glucose disorder and 14.2% had diabetes. Among participants with periodontitis, the prevalence of diabetes was 1.49 times higher in participants with an average sleep duration of ≥8 h than those with an average sleep duration of 6-7 h. The prevalence of diabetes among participants without periodontitis was 1.49 times and 1.57 times higher in participants with an average sleep duration of ≤5 and ≥8 h, respectively, than those with an average sleep duration of 6-7 h. We found that altered sleep duration may be a risk factor for diabetes and that proper sleep duration is important to control diabetes incidence.

Relationship between Insufficient Sleep and Bad Breath in Korean Adolescent Population

This cross-sectional study sought to evaluate the association between insufficient sleep and bad breath among Korean adolescent population. It was based on the 13th Korea Youth Risk Behavior Web-Based Survey (2017). From 64,991 participants (aged 13-18 years), the final participation rate in the survey was 95.8% (62,276 participants; 31,624 boys and 30,652 girls). A complex sample logistic regression was performed to identify the relationship between insufficient sleep and halitosis, after adjusting for all covariates. In Model II for estimating the adjusted odds ratio (AOR) for general characteristics, students who answered "not at all sufficient", indicating insufficient sleep, were at higher risk of bad breath than those who answered "completely sufficient" (AOR = 2.09, 95% confidence interval, CI = 1.91-2.30). In Model III, for estimating the AOR adjusted for all covariates, students who answered "not at all sufficient", indicating insufficient sleep, were at higher risk of bad breath than those who answered "completely sufficient" (AOR = 1.47, 95% CI = 1.33-1.83). It is necessary for families and schools to have health education lessons that recognize insufficient sleep among adolescents may be a cause of bad breath and therefore optimal sleeping habits and oral health behaviors should be promoted.

Is inadequate sleep a potential risk factor for periodontitis?

This study was undertaken to investigate the potential association between sleep duration and periodontitis. The study population consisted of 10,291 individuals who participated in the United States National Health and Nutrition Examination Survey (NHANES) from the 2009–2014 cycles. Sleep duration was categorized into sleep deficient (< 7 hours), sleep adequate (7–8 hours), and sleep excessive (> 8 hours). We used the Center for Disease Control and Prevention (CDC) and the American Academy of Periodontology (AAP) periodontitis case definition. Descriptive statistics and logistic regression models were used for data analyses. The prevalence of periodontitis was 36% higher in individuals who reported sleep deficiency when compared to the sleep adequate group (odds Ratio (OR) = 1.36, 95% confidence interval (CI): 1.23–1.50). Those who reported excessive sleep had 41% higher odds of periodontitis (OR: 1.40, 95% CI: 1.16–1.71). After adjusting for confounding factors, sleep deficient individuals were 19% more likely to have periodontitis when compared to sleep adequate individuals (OR: 1.19, 95% CI: 1.06–1.38). Among sleep excessive individuals, the association was non-significant (OR: 1.16, 95% CI: 0.94–1.43). Sleep deficiency was associated with a higher prevalence of periodontitis in this study population. The association however needs to be confirmed in longitudinal studies.

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.

Periodontal disease, sleep duration, and white blood cell markers in the 2009 to 2014 National Health and Nutrition Examination Surveys

BACKGROUND

Elevated levels of inflammatory biomarkers are consistently associated with chronic conditions, for which periodontitis and sleep are established risk factors. We examined the relationships between periodontitis, hours of sleep and white blood cell (WBC) markers among a nationally representative sample of US adults.

METHODS

Cross-sectional study using existing demographic, examination, laboratory and questionnaire data on 11,813 participants (5,814 men and 5,999 women, mean age ± SE; range: 52.74 ± 0.24; 30 to 80 years) from the 2009 to 2014 National Health and Nutrition Examination Surveys. Unadjusted, sex- and age-adjusted, as well as fully adjusted linear and logistic regression models were conducted in addition to generalized structural equations models, while considering sampling design complexity. β, odds ratios with their 95% confidence intervals, indirect effects and mediation proportions were estimated.

RESULTS

The weighted mean WBC count was 7,130 cells/µL, with the WBC 5-part differential estimated in terms of percentages of lymphocytes (29.50%), monocytes (7.99%), neutrophils (59.03%), eosinophils (2.84%), and basophils (71.88%). Furthermore, 36.2% of participants reported <7 hours of sleep and 49.8% had periodontitis. In fully adjusted models controlling for sociodemographic, lifestyle, and health characteristics, neither WBC markers nor periodontitis were related to hours of sleep. By contrast, periodontitis was directly related to WBC count and %neutrophils and inversely related to %lymphocytes, especially among men. However, the relationship of periodontitis with %neutrophils and %lymphocytes may be modified by hours of sleep, as it was specific to individuals reporting ≥7 hours of sleep.

CONCLUSION

Periodontitis may be directly related to WBC count and %neutrophils and inversely related to %lymphocytes, especially among men and individuals reporting ≥7 hours of sleep, with implications for primary and secondary prevention.

Association between quality of sleep and chronic periodontitis: A case-control study in Malaysian population

BACKGROUND

Periodontitis is a public health concern since it is a major factor in tooth loss worldwide and has association with many systemic diseases. Sleep is a complex and essentially biological process and a critical factor for maintaining mental and physical health. Since inflammation is characteristic of both chronic periodontitis and sleep deprivation, few studies in recent years present the contradictory results regarding this potential association. The objective of the present study was to investigate the association between quality of sleep and chronic periodontitis.

MATERIALS AND METHODS

A total of 200 individuals participated in this study. All participants underwent a comprehensive clinical periodontal examination. Case-control were identified using the Centers for Disease Control and Prevention/American Academy of Periodontology case definitions for periodontal disease. The quality of sleep was assessed by Pittsburgh Sleep Quality Index. The univariate and multivariate logistic regression analysis was used to test the influence of variables (quality of sleep, age, sex, ethnicity, education, and socioeconomic status), in the occurrence of periodontitis. Odds ratio (OR) and respective confidence intervals (CIs) were calculated and reported. P =0.05 was considered statistically significant.

RESULTS

The prevalence of poor quality of sleep was 56.75% in cases (periodontitis group) and 43.24% in control group. There was positive association between quality of sleep and chronic periodontitis (OR = 3.04; 95% CI = 1.42-6.5; P = 0.004). In multivariate logistic regression analysis, only the age was significantly related to the periodontitis (OR = 1.11; 95% CI = 1.07-1.41; P < 0.001), other variables failed to reach the significant level.

CONCLUSION

Poor quality of sleep was significantly associated with chronic periodontitis. Only the age was significantly related to periodontitis among the other covariable measured.

Melatonin promotes reduction in TNF levels and improves the lipid profile and insulin sensitivity in pinealectomized rats with periodontal disease

AIM

This study aimed to investigate the effects of melatonin (ME) on insulin resistance (IR) and signaling (IS), proinflammatory cytokine levels, and lipid profiles in pinealectomyzed (PNX) rats with periodontal disease (PD).

MAIN METHODS

One hundred and forty-four rats (age = 40 days) were distributed into 8 groups: 1) control (CN); 2) PD only; 3) PNX only; 4) PNX and PD (PNXPD); 5) CN treated with ME (CNM); 6) PD treated with ME (PDM); 7) PNX treated with ME(PNXM); 8) PNX and PD treated with ME(PNXPDM). The PNX groups were subjected to pinealectomy at 40 and at 60 days of age. The animals were then subjected to PD induction in the mandibular first molars. After PD induction, the ME replacement therapy (MERT-5 mg/kg body weight) was performed using water for 28 days. After this period, the plasma concentration of glucose, insulin, TNF, IL-6, triglycerides, total cholesterol, HDL-cholesterol, LDL-cholesterol, and VLDL-cholesterol and the HOMA-IR index were determined. Akt serine phosphorylation status in the white adipose tissue, gastrocnemius muscle, and rat liver were also evaluated.

KEY FINDINGS

PD, PNX, and PNXPD groups showed an increase in IR with elevated plasma levels of insulin and TNF compared to CN group. PNX and PNXPD groups presented alteration in lipid profile compared to CN group. MERT improved all of the analyzed parameters. No difference was observed in the IS among different groups.

SIGNIFICANCE

The results suggest that MERT efficiently prevents IR, improves lipid profile, and increases plasma levels of insulin and TNF in PD and PNX rats.

Relationship between Problematic Internet Use, Sleep Problems, and Oral Health in Korean Adolescents: A National Survey

We examined the relationship between Problematic Internet Use (PIU), sleep (sleep satisfaction, sleep duration), and experience of oral disease symptoms in Korean adolescents by gender. This cross-sectional study utilized the 6th (2010) Korean Youth Risk Behavior Web-based Survey. Participants comprised 74,980 students from 400 middle schools and 400 high schools nationwide. Among these, 73,238 students from 799 schools (38,391 boys, 34,847 girls, aged 13–18 years) were included in the analysis (inclusion rate = 97.7%). Multiple logistic regression and analysis of moment structures (AMOS) analyses were performed to identify meaningful relationships between the three factors. The “high risk group” of problematic internet usage had increased experience of oral disease symptoms (boys: adjusted odds ratio (AOR) = 1.92, 95% confidence interval (CI) = 1.63–2.28, girls: AOR = 1.98, 95% CI = 1.50–2.63) compared to the general group. Boys who used the Internet for “5–6 h” had a higher risk of oral disease symptoms compared to those who used it for “less than 1 h” (OR = 1.24, 95% CI = 1.01–1.53); however, this difference was not significant in Models II and III. For girls, the risk of 5–6 h of use (Model I: OR = 1.69, 95% CI = 1.40–2.04) was higher than that of the boys. In addition, the difference was significant in Models II and III for girl students who used the Internet for 5–6 h. In subgroup analysis, the high-risk group had a higher odds ratio for mild symptoms of bad breath to severe symptoms such as sore and bleeding gums. In addition, in the path analysis, PIU affected sleep and indirectly affected oral health. Direct and indirect causal relationships between the three factors were confirmed. Therefore, it is important to recognize that PIU can have a detrimental effect on mental, physical, and oral health.

Evaluation of the association between sleep duration and tooth loss among Korean adults: data from the Korean National Health and Nutrition Examination Survey (KNHANES 2012-2014)

OBJECTIVES

This study assessed the association between sleep duration and tooth loss using nationally representative data. In this study, a cross-sectional analysis was performed using multivariable logistic regression analysis models.

SETTING

The present study analysed data from the Korean National Health and Nutrition Examination Survey between 2012 and 2014.

PARTICIPANTS

A total of 14 675 respondents over 19 years old without missing values were included in this study.

EXPOSURE AND PRIMARY OUTCOME MEASURES

Sleep duration and tooth loss.

RESULTS

Participants with a sleep duration of 6-8 hours showed the lowest prevalence of diabetes mellitus, hypertension, metabolic syndrome, periodontitis and meeting the waist circumference criteria for metabolic syndrome. Adjusted OR and their 95% CI of male individuals with fewer than 25 natural teeth were 1.426 (1.113 to 1.827), 1.290 (1.074 to 1.548), 0.988 (0.853 to 1.145), 1 (reference), 1.058 (0.907 to 1.235) and 1.620 (1.287 to 2.038) for sleep duration of 4 hours or less, 5 hours, 6 hours, 7 hours, 8 hours and 9 hours or more, respectively (p<0.05), after adjustments for age, sex, smoking, drinking, walking, frequency of tooth brushing per day, body mass index and periodontitis.

CONCLUSIONS

Our findings showed the U-shaped association between sleep duration and tooth loss was suggested by multiple logistic regression analyses after adjusting for confounding factors. Moreover, subgroup analyses showed that short and long sleep duration were associated with greater tooth loss in participants without diabetes mellitus, those without hypertension and those without metabolic syndrome.

Relationship between long working hours and periodontitis among the Korean workers

We aimed to investigate the association between long working hours and periodontitis, and whether such an association constitutes an exposure-response relationship. Data for this study were collected from the Korea National Health and Nutrition Examination Surveys conducted from 2007 to 2014; 17,533 workers (9,483 of men and 8,050 of women) were included. The odds ratios (OR) and 95% confidence intervals (CI) for the analysis of periodontitis defined as positive of Community Periodontal Index in relation to working hours were calculated using multiple logistic regression models with various stratifications. Compared to participants who worked ≤40 hours per week, the prevalence ratio (95% CI) for the periodontitis was 1.19 (1.14–1.24) and full adjusted OR (95% CI) was 1.09 (1.02–1.18) in participants who worked over 40 hours per week. The OR (95% CI) for periodontitis were 1.09 (0.99–1.19) in working group of 40< and ≥52 and 1.10 (1.01–1.20) in working group of >52 hours per week with a significant trend (p = 0.0233) even after adjusting for age, socioeconomic status, healthy behaviour, chronic disease, and dental care status. Long working hours are associated with periodontitis among Korean workers in an exposure-response manner.