Systematic Review and Meta-analysis of the Association Between Exposure to Environmental Tobacco Smoke and Periodontitis Endpoints Among Nonsmokers

Interaction Between Tobacco Smoke Exposure and Zinc Intake and Its Effect on Periodontitis: Evidence From NHANES

AIM

Tobacco smoke exposure, zinc intake, and periodontitis are closely related. This study intended to assess the relationship between tobacco smoke exposure and zinc intake and its effect on periodontitis.

MATERIALS AND METHODS

This cross-sectional study included 9364 participants from the National Health and Nutrition Examination Survey (NHANES) of USA. A weighted multivariate logistic regression model was used to investigate the independent relationship and interaction effect among tobacco smoke exposure, zinc intake, and periodontitis. Odds ratio (OR) with 95% confidence interval (CI) was calculated. The additive interaction was evaluated using relative excess risk due to interaction (RERI), attributable proportion of interaction (AP), and synergy index (SI).

RESULTS

In all, 56.57% participants had periodontitis. Compared with participants without tobacco smoke exposure, those with tobacco smoke exposure had increased odds of having periodontitis (OR, 1.96; 95% CI, 1.67-2.31). Similarly, patients with adequate zinc intake were found to have decreased odds of having periodontitis than those with inadequate zinc intake (OR, 0.86; 95% CI, 0.76-0.98). Importantly, there was antagonistic interaction effect between zinc intake and tobacco smoke exposure on periodontitis (RERI: OR,  -0.432; 95% CI, -0.829 to -0.034; AP: OR, -0.242; 95% CI, -0.470 to -0.014; SI:  OR, 0.645; 95% CI, 0.446 to 0.932).

CONCLUSIONS

Tobacco smoke exposure and zinc intake were independently correlated with periodontitis risk. Decreasing tobacco smoke exposure and optimizing dietary zinc intake appear to be important measures that could be taken to control periodontitis.

Association of Sleep Quality and General, Mental, and Oral Health with Lifestyle Traits (Dietary Intake, Smoking Status) in Arthritis: A Cross-Sectional Study from the Canadian Community Health Survey (CCHS)

Arthritis is associated with health challenges. Lifestyle traits are believed to influence arthritis development and progression; however, data to support personalized treatment regimens based on holistic lifestyle factors are missing. This study aims to provide a comprehensive list of associations between lifestyle traits and the health status of individuals with arthritis in the Canadian population, using binary logistic regression analysis on data from the Canadian Community Health Survey, which includes 104,359 respondents. Firstly, we explored the association between arthritis and various aspects of health status including self-reported lifestyle factors. Secondly, we examined the associations between self-reported dietary intake and smoking status with general, mental, and oral health, and sleep disturbance among individuals both with and without arthritis. Our analysis revealed that individuals with arthritis reported considerably poorer general, mental, and oral health, and poorer sleep quality compared to those without arthritis. Associations were also found between self-reported dietary intake and various measures of health status in individuals with arthritis. Smoking and exposure to passive smoking were associated not only with arthritis but also with compromised sleep quality and poorer general, mental, and oral health in people with and without arthritis. This study highlights the need for personalized and holistic approaches that may include a combination of dietary interventions, oral health improvements, sleep therapies, and smoking cessation for improved arthritis prevention and care.

Association of environmental polycyclic aromatic hydrocarbons exposure with periodontitis in NHANES 2009-2014: A mixtures approach

BACKGROUND

Polycyclic aromatic hydrocarbons (PAHs) can invade and cause harm to the human body through various pathways, but there is currently little research on the relationship between mixed-PAHs exposure and periodontitis. The purpose of this study was to examine the effects of mixed-urinary PAHs exposure on periodontitis in adults in the United States.

METHODS

The cross-sectional study included 2749 subjects selected from the National Health and Nutrition Examination Survey (NHANES) 2009-2014 cycles. A professional examination of the periodontal status was conducted to distinguish between periodontitis and non-periodontitis based on the Centers for Disease Control and Prevention/American Academy of Periodontology (CDC/AAP) case definition. Laboratory testing of urine samples was performed to obtain the levels of urinary PAHs. Pearson correlation coefficients were utilized to determine the degree of correlation between urinary PAHs, while weighted binary logistic regression and Bayesian kernel machine regression (BKMR) were employed to evaluate the relationship between urinary PAHs and periodontitis.

RESULTS

In a single-exposure model, 3-hydroxyfluorene (OH-3F), 2-hydroxyfluorene (OH-2F), 1-hydroxyphenanthrene (OH-1Ph), and 2-hydroxyphenanthrene and 3-hydroxyphenanthrene (OH-2,3Ph) were positively associated with periodontitis risk. In the mixed-exposure model, BKMR analysis demonstrated that mixed exposure to urinary PAHs was positively associated with periodontitis, with OH-2F being the most critical factor for the overall mixed effects (posterior inclusion probability [PIP] = 0.98). Univariate exposure-response function and univariate effects analysis revealed a positive correlation between urinary OH-2F levels and periodontitis.

CONCLUSIONS

The study reveals a significant positive correlation between exposure to mixed PAHs and periodontitis, with a particular emphasis on the pivotal role of OH-2F. Mitigating PAHs in the environment may serve as a preventive measure against periodontitis and alleviate its global public health burden.

Association between blood ethylene oxide levels and the prevalence of periodontitis: evidence from NHANES 2013-2014

BACKGROUND

The study aimed to establish a link between blood ethylene oxide (EO) levels and periodontitis, given the growing concern about EO's detrimental health effects.

MATERIALS AND METHODS

The study included 1006 adults from the 2013-2014 National Health and Nutrition Examination Survey (NHANES) dataset. We assessed periodontitis prevalence across groups, used weighted binary logistic regression and restricted cubic spline fitting for HbEO-periodontitis association, and employed Receiver Operating Characteristic (ROC) curves for prediction.

RESULTS

In the periodontitis group, HbEO levels were significantly higher (40.57 vs. 28.87 pmol/g Hb, P < 0.001). The highest HbEO quartile showed increased periodontitis risk (OR = 2.88, 95% CI: 1.31, 6.31, P = 0.01). A "J"-shaped nonlinear HbEO-periodontitis relationship existed (NL-P value = 0.0116), with an inflection point at ln-HbEO = 2.96 (EO = 19.30 pmol/g Hb). Beyond this, ln-HbEO correlated with higher periodontitis risk. A predictive model incorporating sex, age, education, poverty income ratio, alcohol consumption, and HbEO had 69.9% sensitivity and 69.2% specificity. The model achieved an area under the ROC curve of 0.761.

CONCLUSIONS

These findings suggest a correlation between HbEO levels and an increased susceptibility to periodontitis.

Long-term exposure to ambient fine particulate matter and periodontitis: An observational study using nationally representative survey data

AIM

The rising prevalence of periodontitis imposes substantial burdens on individuals and society. Identifying environmental risk factors for periodontitis may contribute to tackling the global public health burden of it. This study aimed to assess the association between long-term exposure to PM2.5 and periodontitis in a nationally representative population from China.

MATERIALS AND METHODS

In this multi-centre cross-sectional study of 372 communities in 31 provinces of Mainland China, we used data from the Fourth National Oral Health Survey of China in 2015-2016, in combination with high-resolution gridded concentrations of fine particulate matter (PM2.5). Logistic regression was applied to assess the relationship between long-term PM2.5 exposure and the risk of periodontitis. In addition, we examined whether the association varied by individual characteristics, and estimated the exposure-response relationship and the risk of damaged tooth in each tooth quadrant.

RESULTS

A total of 8391 participants from 96 cities were diagnosed with periodontitis, accounting for 60.04% (8391/13,459) of the participants. For each 10 μg/m3 increment in 1-, 3- and 5-year average concentrations of PM2.5, the risk of total periodontitis increased by 9.0% (95% confidence interval: 6.0%, 12.0%), 8.0% (6.0, 11·0) and 7.0% (5.0, 10.0), respectively. Mild periodontitis was more strongly associated with PM2.5 exposure than moderate and severe periodontitis. The teeth in the lower anterior, lower posterior or upper anterior are more susceptible to the effect of PM2.5 on the periodontal pocket, calculus and bleeding gums.

CONCLUSIONS

Long-term exposure to PM2.5 is significantly associated with an increased risk of periodontitis in the nationally representative Chinese population. Considering the rising prevalence of periodontitis, considerable costs of treatment, and substantially adverse effects on individuals and society, these findings suggest that stricter air quality regulations may help ease the burden of periodontal disease.

Association between life's essential 8 and periodontitis: a study based on NHANES 2009-2014

Background

This research aims to investigate the relationship between Life's Essentials 8 (LE8), the American Heart Association's latest indicator, and periodontitis. The purpose is to provide guidance on preventative measures.

Methods

Data for our investigation were obtained from the National Health and Nutrition Examination Survey (NHANES) 2009-2014, with a total of 8,784 participants eligible. LE8 scores were compiled from 8 index scores (the score for each component of diet, physical activity, nicotine exposure, sleep duration, body mass index, blood lipids, blood glucose, and blood pressure). Periodontitis was classified by the Centers for Disease Control and Prevention and American Academy of Periodontology (CDC/AAP). The study utilized multivariable logistic analyses to investigate the potential correlation.

Results

After controlling for all covariates, LE8 was discovered to have a significant negative correlation with periodontitis prevalence [0.91 (0.88, 0.94)]. This trend continued to hold statistical significance even after converting LE8 into a categorical variable. Furthermore, a noteworthy adverse correlation was discovered across both genders, specifically males [0.35 (0.22, 0.55)] and females [0.39 (0.25, 0.60)], as well as for the majority of categorical classifications, namely ethnicity, age, education level, and marital status. However, only the age subgroups displayed some degree of significant difference from each other.

Conclusion

Life's essential 8 was negatively associated with periodontitis, but more prospective trails are needed to confirm our findings.

Passive Smoking and Oral Health of Infants, Preschoolers, and Children: A Systematic Review

INTRODUCTION

Almost half of the world's children experience passive smoking, which is linked to numerous oral health conditions. The aim is to synthesize data on the impact of passive smoking on oral health of infants, preschoolers, and children.

AIMS AND METHODS

A search was conducted across Medline (via EBSCOhost), PubMed, and Scopus up to February 2023. Risk of bias was assessed according to the Newcastle-Ottawa Scale (NOS).

RESULTS

The initial search produced 1221 records and after removal of duplicates, screening by title and abstract, and full-text assessment, 25 studies were eligible for review and data extraction. The majority of studies (94.4%) found a correlation between passive smoking and increased prevalence of dental caries with three studies suggesting a dose-response relationship. Prenatal passive smoking exposure in 81.8% of studies indicated an increased dental caries experience compared to postnatal exposure. Low parental education, socioeconomic status, dietary habits, oral hygiene, and gender affected the level of environmental tobacco smoke (ETS) exposure and dental caries risk.

CONCLUSIONS

The results of this systematic review strongly suggest a significant association between dental caries in the deciduous dentition and passive smoking. Early intervention and education on the effects of passive smoking on infants and children will allow for the improvement in oral health outcomes and reduction in smoking-associated systemic conditions. The results justify all health professionals paying more attention to passive smoking when conducting pediatric patient histories, contributing to improved diagnosis and appropriate treatment planning with more suitable follow-up schedules.

IMPLICATIONS

The evidence from this review that environmental tobacco smoke and passive smoking is a risk factor for oral health conditions, both prenatally and postnatally during early childhood, justifies all health professionals paying more attention to passive smoking when conducting pediatric patient histories. Early intervention and appropriate parental education regarding the effects of secondhand smoke on infants and children will allow for the minimization of dental caries, improvement in oral health outcomes and overall reduction in smoking-associated systemic conditions for the children exposed.

Oral-malodor measurement and intention to quit smoking in men: A before-after study

INTRODUCTION

Few studies have examined the effect of feedback based on oral-malodor measurements on the motivation to quit smoking. Therefore, this study examined whether oral-malodor measurements were associated with the intention to quit smoking.

METHODS

This retrospective, uncontrolled before-after study invited smokers to a workplace health event in 2019 and 2020 to motivate them to quit smoking. They attended seminars on oral health and smoking cessation aids, and then underwent respiratory function and oral-malodor measurements using exhaled and oral cavity air, respectively. Intention to quit smoking was evaluated by answers to questions regarding the intention to quit in the next 1 or 6 months in questionnaires collected before and after the event. This study analyzed 241 men aged 20-54 years (mean: 33.2 ± 10.5) to examine factors associated with the intention to quit in multivariable logistic regression analyses for age, tobacco type (cigarettes and heated-tobacco products), and category of tobacco consumption.

RESULTS

Before the event, 8.7%, 17.0%, and 74.3% of smokers had intended to quit in the next month, the next six months, or had no intention to quit, respectively. After the event, the respective percentages were 17.8%, 26.6%, and 55.6%. A higher methyl mercaptan concentration, a volatile sulfide component of oral malodor, was significantly associated with the intention to quit in the next month (adjusted odds ratio, AOR=4.24; 95% CI: 1.52-11.8, p=0.006). The participants with higher daily tobacco consumption were less likely to acquire the intention to quit in the next six months (AOR=0.37; 95% CI: 0.15-0.92, p=0.032). Other variables, such as lung age deficit, exhaled CO concentration, and hydrogen sulfide concentration (another component of oral malodor), were not significantly associated.

CONCLUSIONS

Oral-malodor measurement feedback may help motivate men to quit smoking in the next 1 month rather than in the next six months.

Influence of Smoking on Periodontal and Implant Therapy: A Narrative Review

BACKGROUND

smoking is considered the most modifiable risk factor for periodontal disease.

OBJECTIVE

the aim of this narrative review is to emphasize the effect of smoking on periodontal and implant therapy.

METHODS

The authors reviewed the literature reporting the clinical outcomes of smoking on periodontal surgical and nonsurgical treatment. The impact of smoking on implant therapy and sinus lifting procedures were also reviewed.

RESULTS

Periodontal and implant therapy outcomes are adversely affected by smoking. Smokers respond less favorably to periodontal therapy and periodontal flap procedures as compared to nonsmokers. Clinical outcomes for smokers are 50-75% worse than for nonsmokers. Studies reveal that smokers experience a significantly lower reduction in pocket depth compared to nonsmokers as well as less bone growth after treating infra-bony defects with guided tissue regeneration. The relative risk of implant failure is significantly higher in patients who smoke 20 cigarettes or more per day compared to nonsmokers. Additionally, smoking has also been shown to increase postoperative wound dehiscence and infection rates following sinus floor elevation. Longitudinal studies on smoke cessation have shown a reduction in bone loss and probing depths for periodontitis patients after cessation compared to those who smoke.

CONCLUSION

Smoking cessation can reduce probing depths and improve clinical attachment after nonsurgical periodontal therapy. There is insufficient evidence regarding the effect of smoking on peri-implantitis, as well as the loss of implants in the long-term.

Boric Acid Reverses Nicotine-Induced Cytokine Expressions of Human Gingival Fibroblasts

Nicotine, the major bioactive ingredient in tobacco, is a major risk factor for periodontal disease and destruction. Nicotine has been shown to stimulate the production of cytokines that are priming agents for inflammation that induces tissue destruction, such as IL-1β, IL-6, and IL-8, by gingival keratinocytes and human gingival fibroblasts (HGF). Boron as boric acid has been found to decrease pro-inflammatory cytokines and increase anti-inflammatory cytokines in cells with inflammatory stress. Thus, a study was performed to determine whether boric acid reverses negative effects of nicotine on human gingival fibroblasts (HGFs). The viability and cytokine expressions of HGFs cultured for 24 and 72 h in control medium with no nicotine or boric acid added and in media containing only nicotine, only boric acid, or a combination of BA and nicotine were determined. Nicotine in concentrations of 10^-1, 10^-2, 10^-3,10^-4, 10^-5, and 10^-6 mM significantly reduced cell viability compared to the control. Boric acid at 10 and 50 ng/mL in the media partially restored and 100 ng/mL in the media fully restored the nicotine-depressed HGF cell viability to the same level as the control group. Nicotine elevated the expression of pro-inflammatory cytokines TNF-α, IL-1β, IL-6, IL-8, and IL-17 and decreased the anti-inflammatory IL-10 in HGFs at 24 and 72 h. Boric acid at 100 ng/mL in the medium prevented the changes induced by nicotine alone. The findings indicate that boric acid can inhibit or reverse nicotine-induced pathology in periodontal tissue and thus may help maintain oral and periodontal health in tobacco users.

Assessment of the contextual effects on the prevalence of periodontitis: a systematic review

This study reviews the influence of contextual factors on periodontitis based on a systematic search of studies recorded in the PubMed, Scopus, Web of Science, and EMBASE databases. Periodontitis was assessed by clinical attachment loss and probing depth for studies with data on the socioeconomic status (SES) of a specific area (area-level SES) or dental care service (service-level) in a catchment area among individuals aged 18 and over. Two independent reviewers performed study selection, data extraction, and assessment of methodological quality. Of the 646 articles identified, 13 were included in the systematic review, representing 101,362 individuals from five countries (USA, UK, Brazil, China, and Uruguay). A higher prevalence of periodontitis was described in lower SES neighborhoods, more deprived postcodes, and poorer provinces. Gini Index results were mixed and inconclusive. Three studies showed that higher coverage of primary dental care at the municipal level was associated with a lower prevalence of periodontitis. Contextual factors at the area-level SES and dental care service might influence periodontitis, but the existing evidence is unclear. The contextual effect is important for periodontal health and may contribute to the prevalence of periodontitis, independent of well-known risk factors and individual levels.

Tobacco smoke exacerbates Filifactor alocis pathogenicity

AIM

Filifactor alocis has recently emerged as a periodontal pathobiont that appears to thrive in the oral cavity of smokers. We hypothesized that identification of smoke-responsive F. alocis genes would provide insight into adaptive strategies and that cigarette smoke would enhance F. alocis pathogenesis in vivo.

MATERIALS AND METHODS

F. alocis was grown in vitro and cigarette smoke extract-responsive genes determined by RNAseq. Mice were exposed, or not, to mainstream 1R6F research cigarette smoke and infected with F. alocis, or not, in an acute ligature model of periodontitis. Key clinical, infectious, and immune data were collected.

RESULTS

In culture, F. alocis growth was unaffected by smoke conditioning and only a small number of genes were specifically regulated by smoke exposure. Reduced murine mass, differences in F. alocis-cognizant antibody production, and altered immune profiles as well as altered alveolar bone loss were all attributable to smoke exposure and/or F. alocis infection in vivo.

CONCLUSIONS

F. alocis is well-adapted to tobacco-rich conditions and its pathogenesis is enhanced by tobacco smoke exposure. A smoke-exposed ligature model of periodontitis shows promise as a tool with which to further unravel mechanisms underlying tobacco-enhanced, bacteria-induced disease.

Effect of Exposure to Paternal Smoking on Overweight and Obesity in Children: Findings from the Children Lifeway Cohort in Shenzhen, Southern China

INTRODUCTION

Paternal smoking associated with childhood overweight and obesity has been a concern, but studies have not investigated smoking exposure and smoking details. We investigated the association of exposures from paternal smoking as well as smoking details on offspring overweight/obesity.

METHODS

A total of 4,513 children (aged 7-8 years) in Shenzhen were enrolled. Four different exposures from paternal smoking as well as smoking quantity, duration of smoking, and age of starting smoking details were the exposure variables and demographic characteristics, and circumstances of birth, dietary intake, lifestyle, and nonpaternal-smoking exposure were covariates in the logistic regression analysis to determine the effect of paternal smoking on childhood overweight/obesity, estimating odds ratios (ORs), and 95% confidence intervals (CIs).

RESULTS

Paternal smoking was positively associated with childhood overweight/obesity (p < 0.05). Moreover, only preconception exposure, and both pre- and postconception exposure were significantly associated with childhood overweight/obesity (OR 1.54 [95% CI: 1.14-2.08] and OR 1.73 [95% CI: 1.14-2.61], respectively), restricted to boys but not girls. Furthermore, for children with only preconception paternal-smoking exposure, the dose-response relation was positive between smoking quantity, duration of smoking, age at starting, and overweight/obesity for boy offspring (p trend <0.001). We did not find any significant association between only postnatal exposure to paternal smoking and childhood overweight/obesity (p > 0.05).

CONCLUSIONS

Our findings suggest that paternal smoking is associated with boys' overweight/obesity, and this association may be due to the paternal-smoking exposure before conception rather than the postnatal exposure to paternal smoking. Reducing paternal-smoking exposure before conception might help reduce overweight/obesity in boys.

Prevalence of periodontitis in people clinically diagnosed with diabetes mellitus: a meta-analysis of epidemiologic studies

AIMS

The relationship between diabetes mellitus and periodontitis has long been discussed, but the conclusion of this relationship was controversial. We conducted this meta-analysis to explore the association between diabetes mellitus and the prevalence of periodontitis.

METHODS

PubMed, Embase, Web of Science, and the Cochrane Library were searched for studies reporting associations of periodontitis with diabetes. Gray literature was integrated from the Open-Gray database. Prevalence estimates and odds ratios were extracted by two independent reviewers and synthesized through meta-analyses.

RESULTS

Twenty-seven papers met the inclusion criteria involving 3092 diabetic patients and 23,494 controls. Overall prevalence of periodontitis was 67.8% in diabetics (combined types) and 35.5% in patients without diabetes (OR, 1.85; 95%CI, 1.61-2.11). Probing depth (MD 0.23; 95% CI, 0.17-0.29; I² = 25%) and plaque index (MD, 0.20; 95% CI, 0.18-0.23; P = 0.59; I² = 0%) severity scores were significantly greater among the diabetic group.

CONCLUSIONS

The prevalence and severity of periodontitis are greater in patients with diabetes than in non-diabetic populations.

Qualitative and quantitative assessment of the potential effect of cigarette smoking on enamel of human smokers' teeth

OBJECTIVE

This study aimed to examine the potential changes in enamel surface of human smokers' teeth.

MATERIALS AND METHODS

Forty extracted permanent, human, noncarious anterior teeth were used in this study. Half of these teeth were obtained from heavy smokers, while the other half of teeth were collected from nonsmokers (control teeth). The teeth were then subjected for scanning electron microscopic examination together with energy dispersive X ray and micro-hardness analysis to evaluate the qualitative and quantitative effect of smoking respectively.

RESULTS

SEM of smokers' teeth showed variable degrees of destruction from small areas of demineralization as holes and pits to destruction and deterioration of the organizational pattern of the rod substance. Moreover, areas of defective remineralization were detected. The microhardness, calcium and phosphorus weight % significantly decreased whereas the Ca/P ratio was significantly increased.

CONCLUSION

Cigarette smoking adversely affected the ultrastructure and mechanical properties of enamel and even hindered the normal remineralization process thus cigarette smoking cessation should be promoted in the dental office daily practices.

Effect of environmental tobacco smoke on COX-2 and SHP-2 expression in a periodontitis rat model

OBJECTIVES

To investigate the effects of environmental tobacco smoke (ETS) on the inflammatory process of periodontitis by evaluating bone loss and the expression of cyclooxygenase-2 (COX-2) and Src homology phosphotyrosine phosphatase 2 (SHP-2).

MATERIALS AND METHODS

Eighty 6-month-old male SD rats were randomized into four groups (10 rats/group/per time point): (a) normal group, (b) ETS group, (c) ligature-induced periodontitis group, and (d) ligature-induced periodontitis + ETS group. After treatment with ligature and/or ETS for 8 and 12 weeks, the levels of alveolar bone resorption and the expressions of COX-2 and SHP-2 in periodontal tissue were analyzed using histology and immunohistochemistry.

RESULTS

The ligature-induced periodontitis group displayed increased bone resorption and elevated expression of COX-2 and SHP-2 in periodontal tissues compared to the normal and ETS groups at 8 and 12 weeks. Furthermore, bone resorption and COX-2 and SHP-2 levels in the ligature-induced periodontitis + ETS group were significantly increased compared to those in the normal and ligature-induced periodontitis groups at both 8 and 12 weeks.

CONCLUSION

Environmental tobacco smoke increased alveolar bone loss in periodontitis with enhanced expression of COX-2 and SHP-2 in periodontal tissues. Further investigation is needed to explore the role of COX-2 and SHP-2 in ETS-associated periodontitis.

Does second-hand smoke associate with tooth loss among older Japanese? JAGES cross-sectional study

OBJECTIVE

Second-hand smoke (SHS) is considered a risk factor for a number of oral diseases. However, its influence on tooth loss, which is the final consequence of periodontal disease and caries, remains unknown. We aimed to evaluate the association between SHS experience and the number of remaining teeth among non-smoking older Japanese individuals.

METHODS

Cross-sectional data from the Japan Gerontological Evaluation Study (JAGES) 2013 were used. From the 27,561 people ≥65 years of age who responded to a self-reported questionnaire (response rate = 71.1%), data of 18,865 respondents who had never smoked were analysed. Multinomial logistic regression with multiple imputations was applied to estimate the odds ratio of the frequency of SHS exposures on the number of remaining teeth.

RESULTS

The prevalence of participants with ≥20 teeth, 10-19 teeth, 5-9 teeth, 1-4 teeth, and no teeth were 53.2%, 20.4%, 9.9%, 6.6%, and 9.9%, respectively. The proportion of participants with SHS was 37.5%. After adjusting for sex, the SHS experience tended to be associated with a lower risk of having the fewer number of remaining teeth (P < 0.05). However, after being adjusted for age and sex, participants with SHS exposure at "a few times a week" and "almost every day" were significantly associated with the fewer number of teeth. After adding all other covariates, compared to the participants without any exposure to SHS, the odds ratio for having no teeth rather than having ≥20 teeth among the participants with daily exposure to SHS was 1.35 (P < 0.01).

CONCLUSION

Daily second-hand smoke was significantly associated with fewer remaining teeth based on the self-reported survey among older Japanese people.

Effect of tobacco on periodontal disease and oral cancer

INTRODUCTION

Periodontal disease and oral cancer are common health hazards. Epidemiological investigations show that smoking, periodontal disease and oral cancer are closely related. Tobacco is one of the major risk factors for periodontitis and oral cancer.

METHODS

A systematic literature review was performed. To identify relevant studies, the following online databases were searched using specific keywords: PubMed, Web of Science and CNKI.

RESULTS

Tobacco not only possesses an addictive effect, but it aggravates periodontal disease by promoting the invasion of pathogenic bacteria, inhibiting autoimmune defense, aggravating the inflammatory reaction, and aggravating the loss of alveolar bone. According to current evidence, tobacco significantly aggravates the development and progression of periodontal disease and oral cancer, and periodontal disease may be related to the prevalence of oral cancer.

CONCLUSIONS

Clinicians should strongly recommend that smokers undertake a strategy to stop smoking to avoid the exacerbation of nicotine-related periodontal disease and to reduce the incidence of oral cancer.

Microbiological and biochemical findings in relation to clinical periodontal status in active smokers, non-smokers and passive smokers

INTRODUCTION

Cigarette users are more susceptible than non-smokers to periodontitis, a bacterial-induced, inflammation-driven, destructive disease of the supporting tissues of the teeth. We hypothesized that clinical periodontal findings and microbiological and/or inflammatory marker levels would be intermediate in those exposed to environmental tobacco smoke compared to active smokers and non-smokers.

METHODS

Sixty individuals were recruited from a University periodontal clinic and assigned as non-smokers, active smokers or passive-smokers according to their self reports. Clinical periodontal measurements, comprising plaque index, probing depth (PD), clinical attachment level (CAL) and bleeding on probing, were recorded at six sites per tooth. Cotinine levels were determined in whole saliva samples by EIA. Treponema denticola and Porphyromonas gingivalis infection was determined by PCR, while matrix metalloproteinase-8 (MMP-8) and interleukin-8 (IL-8) concentrations were determined by ELISA.

RESULTS

Study groups were subsequently reassigned in accordance with the cotinine data. The smoker group exhibited higher mean PD and CAL values compared to the non-smoker group (p<0.05). Passive-smokers exhibited PD and CAL values smaller than those of the active smokers and greater than those of the non-smokers, but the differences were not statistically significant. PD and CAL values correlated with cotinine concentrations (p<0.05). P. gingivalis infection was noted in most subjects, irrespective of smoking status. T. denticola infection was noted in 4/23 (17.4%) smokers, 0/16 (0%) environmentally-exposed recruits and 2/21 (9.5%) non-smokers. Salivary MMP-8 and IL-8 levels were lower in smokers compared to both non-smokers and passive-smokers but the differences were not significant (all p>0.05).

CONCLUSIONS

The present clinical periodontal findings provide further support for a negative, dose-related effect of tobacco exposure on periodontal health. The tendency for a more prevalent detection of T. denticola and for a suppressed inflammatory response observed in the smokers may partly explain the increased susceptibility to periodontal tissue destruction, but needs to be verified in larger scale studies.

Tobacco-induced suppression of the vascular response to dental plaque

Cigarette smoking presents oral health professionals with a clinical and research conundrum: reduced periodontal vascular responsiveness to the oral biofilm accompanied by increased susceptibility to destructive periodontal diseases. This presents a significant problem, hampering diagnosis and complicating treatment planning. The aim of this review is to summarize contemporary hypotheses that help to explain mechanistically the phenomenon of a suppressed bleeding response to dysbiotic plaque in the periodontia of smokers. The influence of smoke exposure on angiogenesis, innate cell function, the production of inflammatory mediators including cytokines and proteases, tobacco-bacteria interactions, and potential genetic predisposition are discussed.

Regular nicotine intake increased tooth movement velocity, osteoclastogenesis and orthodontically induced dental root resorptions in a rat model

Orthodontic forces have been reported to significantly increase nicotine-induced periodontal bone loss. At present, however, it is unknown, which further (side) effects can be expected during orthodontic treatment at a nicotine exposure corresponding to that of an average European smoker. 63 male Fischer344 rats were randomized in three consecutive experiments of 21 animals each (A/B/C) to 3 experimental groups (7 rats, 1/2/3): (A) cone-beam-computed tomography (CBCT); (B) histology/serology; (C) reverse-transcription quantitative real-time polymerase chain reaction (RT-qPCR)/cotinine serology—(1) control; (2) orthodontic tooth movement (OTM) of the first and second upper left molar (NiTi closed coil spring, 0.25 N); (3) OTM with 1.89 mg·kg⁻¹ per day s.c. of L(−)-nicotine. After 14 days of OTM, serum cotinine and IL-6 concentration as well as orthodontically induced inflammatory root resorption (OIIRR), osteoclast activity (histology), orthodontic tooth movement velocity (CBCT, within 14 and 28 days of OTM) and relative gene expression of known inflammatory and osteoclast markers were quantified in the dental-periodontal tissue (RT–qPCR). Animals exposed to nicotine showed significantly heightened serum cotinine and IL-6 levels corresponding to those of regular European smokers. Both the extent of root resorption, osteoclast activity, orthodontic tooth movement and gene expression of inflammatory and osteoclast markers were significantly increased compared to controls with and without OTM under the influence of nicotine. We conclude that apart from increased periodontal bone loss, a progression of dental root resorption and accelerated orthodontic tooth movement are to be anticipated during orthodontic therapy, if nicotine consumption is present. Thus patients should be informed about these risks and the necessity of nicotine abstinence during treatment.

Influence of involuntary cigarette smoke inhalation on osseointegration: a systematic review and meta-analysis of preclinical studies

There are no studies that have systematically reviewed the influence of involuntary cigarette smoke inhalation (ICSI) on the stability of implants. The aim of the present study was to perform a systematic review and meta-analysis of preclinical studies that assessed the influence of involuntary cigarette smoke inhalation ICSI on osseointegration. Indexed databases (PubMed, Google-Scholar, Scopus, EMBASE, and Web of Knowledge) were searched till September 2017. Titles and abstracts of studies identified using the above-described protocol were independently screened by 2 authors. Full-texts of studies judged by title and abstract to be relevant were independently evaluated for the stated eligibility criteria. Nine studies were included. Six studies showed that ICSI compromised bone area contact around implants. In 4 studies, peri-implant bone mineral density was significantly higher in the control group than among subjects exposed to ICSI. For the effects of ICSI on the osseointegration of dental implants, significant differences could be observed for bone-to-implant contact for test subjects in cancellous (Z=-4.08, p<0.001) and cortical bone (Z=-4.31, p<0.001) respectively. ICSI may negatively influence osseointegration of dental implants. It is imperative to educate patients about the negative effects of passive smoking on dental and systemic health.