Effect of teenage smoking on the prevalence of periodontal bacteria

Smoking Impacts Alzheimer's Disease Progression Through Oral Microbiota Modulation

Alzheimer's disease (AD) is an important public health challenge with a limited understanding of its pathogenesis. Smoking is a significant modifiable risk factor for AD progression, and its specific mechanism is often interpreted from a toxicological perspective. However, microbial infections also contribute to AD, with oral microbiota playing a crucial role in its progression. Notably, smoking alters the ecological structure and pathogenicity of the oral microbiota. Currently, there is no systematic review or summary of the relationship between these three factors; thus, understanding this association can help in the development of new treatments. This review summarizes the connections between smoking, AD, and oral microbiota from existing research. It also explores how smoking affects the occurrence and development of AD through oral microbiota, and examines treatments for oral microbiota that delay the progression of AD. Furthermore, this review emphasizes the potential of the oral microbiota to act as a biomarker for AD. Finally, it considers the feasibility of probiotics and oral antibacterial therapy to expand treatment methods for AD.

Subgingival Microbiota Profile in Association with Cigarette Smoking in Young Adults: A Cross-Sectional Study

While smoking is recognized as one of the factors for the development and progression of periodontal diseases, a relation between the composition of the subgingival microbiota and smoking is yet to be elucidated. The aim of this study was to investigate the prevalence of subgingival bacteria in young smokers and non-smokers without clinical signs of periodontal disease. In this cross-sectional study, performed at the Department of Pharmacology, School of Dental Medicine, University of Zagreb, we enrolled 32 periodontally healthy smokers and 32 non-smokers, aged 25–35 years old. The number of oral bacteria and the prevalence of particular bacteria were assessed for each subject. Subgingival plaque samples were collected with sterile paper points from two first molars for microbiological analyses with MALDI-TOF mass spectrometry. In smokers, a significantly higher prevalence of Actinomyces odontolyticus was observed compared to non-smokers, and a significantly lower prevalence of Streptococcus sanguinis was observed compared to non-smokers. Smoking affects the composition of subgingival microbiota, either via depletion of beneficial bacteria or the increase in pathogenic bacteria.

The impact of smoking different tobacco types on the subgingival microbiome and periodontal health: a pilot study

Smoking is a risk factor for periodontal disease, and a cause of oral microbiome dysbiosis. While this has been evaluated for traditional cigarette smoking, there is limited research on the effect of other tobacco types on the oral microbiome. This study investigates subgingival microbiome composition in smokers of different tobacco types and their effect on periodontal health. Subgingival plaques were collected from 40 individuals, including smokers of either cigarettes, medwakh, or shisha, and non-smokers seeking dental treatment at the University Dental Hospital in Sharjah, United Arab Emirates. The entire (~ 1500 bp) 16S rRNA bacterial gene was fully amplified and sequenced using Oxford Nanopore technology. Subjects were compared for the relative abundance and diversity of subgingival microbiota, considering smoking and periodontal condition. The relative abundances of several pathogens were significantly higher among smokers, such as Prevotella denticola and Treponema sp. OMZ 838 in medwakh smokers, Streptococcus mutans and Veillonella dispar in cigarette smokers, Streptococcus sanguinis and Tannerella forsythia in shisha smokers. Subgingival microbiome of smokers was altered even in subjects with no or mild periodontitis, probably making them more prone to severe periodontal diseases. Microbiome profiling can be a useful tool for periodontal risk assessment. Further studies are recommended to investigate the impact of tobacco cessation on periodontal disease progression and oral microbiome.

Environmental factors and periodontal microbiome

Periodontal diseases are chronic inflammatory, multifactorial diseases where the major triggering factors for disease onset are bacteria and their toxins, but the major part of tissue destruction occurs as a result of host response towards the periodontal microbiome. Periodontal microbiome consists of a wide range of microorganisms including obligate and facultative anaerobes. In health, there is a dynamic balance between the host, environment, and the microbiome. Environmental factors, mainly tobacco smoking and psychological stress, disrupt the symbiotic relationship. Tobacco smoke and its components alter the bacterial surface and functions such as growth. Psychological stressors and stress hormones may affect the outcome of an infection by changing the virulence factors and/or host response. This review aims to provide currently available data on the effects of the major environmental factors on the periodontal microbiome.

Quantification of pathogenic bacteria in the subgingival oral biofilm samples collected from cigarette-smokers, individuals using electronic nicotine delivery systems and non-smokers with and without periodontitis

OBJECTIVE

The aim of the present study was to quantify pathogenic bacteria isolated from the subgingival oral-biofilm samples collected from cigarette-smokers and ENDS-users with periodontitis, when compared to non-smokers with and without periodontitis.

METHODS

Demographic data was collected using a questionnaire. Periodontal parameters (plaque [PI] and gingival [GI] indices, clinical attachment loss [CAL], probing depth [PD] and marginal bone loss [MBL]) were measured. Subgingival oral bio-film samples were collected and assessed for periodontopathogenic bacteria (Aggregatibacter actinomycetemcomitans [A. actinomycetemcomitans], Prevotella intermedia [P. intermedia], Porphyromonas gingivalis [P. gingivalis], Tannerella forsythia [T. forsythia] and Treponema denticola [T. denticola]). Group-comparisons were performed; and P < 0.01 were considered statistically significant.

RESULTS

All cigarette-smokers, ENDS-users and non-smokers with periodontitis had Grade-B periodontitis. The CFU/mL of A. actinomycetemcomitans (P < 0.001) and P. gingivalis (P < 0.001) were significantly higher among cigarette-smokers (P < 0.01) and ENDS-users (P < 0.01) than non-smokers with periodontitis. The CFU/mL of T. denticola were significantly higher among cigarette-smokers (P < 0.001), ENDS-users (P < 0.001) and non-smokers with periodontitis (P < 0.001) compared with non-smokers without periodontitis. There was no statistically significant difference in the CFU/mL of P. intermedia and T. denticola among cigarette-smokers, ENDS-users and non-smokers with periodontitis.

CONCLUSION

Counts of periodontopathogenic bacteria in the subgingival oral-biofilm are comparable among cigarette-smokers and individuals using ENDS.

The Impact of Smoking on Subgingival Microflora: From Periodontal Health to Disease

Periodontal disease is one of the most common diseases of the oral cavity affecting up to 90% of the worldwide population. Smoking has been identified as a major risk factor in the development and progression of periodontal disease. It is essential to assess the influence of smoking on subgingival microflora that is the principal etiological factor of the disease to clarify the contribution of smoking to periodontal disease. Therefore, this article reviews the current research findings regarding the impact of smoking on subgingival microflora and discusses several potential mechanisms. Cultivation-based and targeted molecular approaches yield controversial results in determining the presence or absence of smoking-induced differences in the prevalence or levels of certain periodontal pathogens, such as the “red complex.” However, substantial changes in the subgingival microflora of smokers, regardless of their periodontal condition (clinical health, gingivitis, or periodontitis), have been demonstrated in recent microbiome studies. Available literature suggests that smoking facilitates early acquisition and colonization of periodontal pathogens, resulting in an “at-risk-for-harm” subgingival microbial community in the healthy periodontium. In periodontal diseases, the subgingival microflora in smokers is characterized by a pathogen-enriched community with lower resilience compared to that in non-smokers, which increases the difficulty of treatment. Biological changes in key pathogens, such as Porphyromonas gingivalis, together with the ineffective host immune response for clearance, might contribute to alterations in the subgingival microflora in smokers. Nonetheless, further studies are necessary to provide solid evidence for the underlying mechanisms.

Oropharyngeal Microbiome in Obstructive Sleep Apnea: Decreased Diversity and Abundance

STUDY OBJECTIVES

To explore and analyze diversity and abundance of oropharyngeal microbiota in patients with obstructive sleep apnea (OSA).

METHODS

This was a cross-sectional study. Middle-aged men, suspected to have OSA, referred to full-night polysomnography, and willing to provide oropharyngeal swab samples, were consecutively enrolled. OSA severity was assessed by apnea-hypopnea index (AHI) as non-OSA (AHI < 5 events/h) and OSA (AHI ≥ 15 events/h). Bacterial DNA of oropharyngeal samples was extracted and quality test performed. Oropharyngeal microbiota was analyzed using 16S ribosomal DNA (rDNA) sequencing, and bioinformatic analysis carried out after sequencing.

RESULTS

Samples from 51 men (25 in the non-OSA group and 26 in the OSA group) were sent for examination. Of these, 40 samples were found to have sufficient concentration of DNA and were analyzed for bioinformatics. In alpha diversity analysis, the OSA group exhibited significantly lower sobs (198.33 ± 21.71 versus 216.57 ± 26.21, P = .022), chao (221.30 ± 26.62 versus 243.86 ± 26.20, P = .014), ace (222.17 ± 27.15 versus 242.42 ± 25.81, P = .028) and shannon index (3.14 ± 0.23 versus 3.31 ± 0.26, P = .035), suggesting a reduction in microbial species diversity. We further divided participants into non-OSA, moderate OSA, and severe OSA groups and observed a significant decrease in the bacterial biodiversity of OSA groups compared with the non-OSA group, with the most significant decrease occurring in the moderate OSA group. Principal coordinate analysis showed two extremely different oropharyngeal microbial communities in non-OSA and OSA groups. More interestingly, proportion of Neisseria was slightly higher in the severe OSA group (20.64%), followed by the moderate OSA and non-OSA groups (12.57% and 9.69%, respectively). Glaciecola was not detected in the OSA groups compared to the non-OSA group (0 versus 0.772 ± 0.4754, P < .001).

CONCLUSIONS

Middle-aged men with OSA showed less oropharyngeal species diversity and altered abundance, on which further confirmation is warranted.

Smoking and periodontal microorganisms

Resolution of dysbiosis following treatment for periodontal disease and tobacco dependence has been reported in longitudinal intervention studies. In the present report, we evaluated the biological findings regarding the effect of smoking on the periodontal microbiome. A standardized electronic search was conducted using MEDLINE; overall, 1099 papers were extracted. Studies that addressed the relationship between tobacco and periodontal pathogens were included. Finally, 42 papers were deemed appropriate for the present review. Functional changes in periodontal pathogens exposed to nicotine and cigarette smoke extract support the clinical findings regarding dysbiosis of the subgingival microbiome. Dysbiosis of the periodontal microbiome was presented in smokers regardless of their periodontal condition (healthy, gingivitis, or periodontitis) and remained significant only in smokers even after the resolution of experimentally-induced gingivitis and following reduction of clinical signs of periodontitis with non-surgical periodontal treatment and over 3 months post-therapy. Based on these findings, smoking cessation in periodontitis patients is beneficial for promoting a health-compatible subgingival microbial community. To maximize the benefits of these interventions in dental settings, further studies on periodontal microbiome are needed to elucidate the impact of tobacco intervention on preventing recurrence of periodontal destruction in the susceptible subjects.

Cross-sectional analysis of risk factors for subclinical periodontitis; active matrix metalloproteinase-8 as a potential indicator in initial periodontitis in adolescents

BACKGROUND

The aim of this study was to investigate how different patient-related risk indicators might be associated with the odds of developing subclinical periodontitis in adolescents.

METHODS

This cross-sectional study included 252 Finnish individuals aged 15 to 16 years, of whom 141 were boys and 111 girls. A specially trained dentist performed clinical examinations: measurements included periodontal indexes (bleeding on probing, visible plaque index, root calculus, and probing depth, smoking by pack-years, periodontal bacteria (Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, Prevotella intermedia, Prevotella nigrescens, and Treponema denticola) and the potential salivary periodontal biomarkers (active matrix metalloproteinase-8 [aMMP-8], polymorphonuclear leukocyte elastase [PMN elastase], and total protein, albumin, immunoglobulin A, immunoglobulin G, and immunoglobulin M). Results were analyzed by ordinal logistic regression, one-way analysis of variance, Fisher exact test, and Kruskal-Wallis H test.

RESULTS

The main finding of this study was that subclinical periodontitis in adolescents was statistically significantly associated with elevated salivary aMMP-8 but not with PMN elastase. Also, adolescents with subclinical periodontitis had statistically significantly higher levels of bleeding on probing, root calculus, and dental plaque than adolescents without subclinical periodontitis.

CONCLUSIONS

We suggest that the main risk factor for subclinical periodontitis in adolescents is the partly calcified, dysbiotic bacterial biofilm, which interacts with the immune defenses of the host; this leads to gingival inflammation and eventually to deepening periodontal pockets. This proinflammatory subclinical periodontitis stage, which represents stage I periodontitis in the new classification, is reflected as elevated salivary aMMP-8 levels in oral fluids.

Stress-related hormones in association with periodontal condition in adolescents-results of the epidemiologic LIFE Child study

OBJECTIVES

The aim of this study was to investigate the associations between blood levels of stress-related hormones and early signs of periodontal disease in children and adolescents.

MATERIALS AND METHODS

Within the LIFE (Leipzig research center for civilization diseases) Child study, 498 adolescents (10 to 18 years) were included. Early signs of periodontal inflammation were measured by probing depth (PD) at six index teeth (16, 11, 26, 36, 31, 46). Blood levels of stress-related hormones (cortisol, dehydroepiandosterone-sulfate [DHEA-S]) and, additionally interleukine-6 (IL-6) were measured. Socioeconomic status, oral hygiene, orthodontic appliances, and nutritional status, recorded by body-mass-index-standard-deviation-score (BMI-SDS), were considered as confounding factors. Additionally, in 98 participants, an oral chairside active matrix metalloproteinase-8 (aMMP-8) test was performed. Statistical tests are the Mann-Whitney U tests, chi-squared tests and multivariate logistic regression model.

RESULTS

IL-6, BMI-SDS as well as positive aMMP-8 test result were significantly associated with maximum PD > 3 mm (p < 0.05). However, no statistically significant associations between stress-related hormones (cortisol and DHEA-S) and presence of maximum PD > 3 mm were found (p > 0.05). Higher DHEA-S and BMI were associated with positive aMMP-8 result, even after adjusting for age and gender (p = 0.027, p_adj = 0.026).

CONCLUSION

The results reveal no associations between PD and stress-related hormones cortisol and DHEA-S. aMMP-8 test result might be associated with DHEA-S level. Nutritional status seems to influence periodontal disease in adolescents.

CLINICAL RELEVANCE

DHEA-S and BMI-SDS show associations with early signs of periodontal disease in adolescents aged 10 to 18 years. This association should be confirmed by the investigation of high-risk groups.

aMMP-8 in correlation to caries and periodontal condition in adolescents-results of the epidemiologic LIFE child study

OBJECTIVES

The suitability of a chairside aMMP-8 test in determination of periodontal inflammation and caries in adolescents was assessed. Secondly, the influence of orthodontic treatment on aMMP-8 test result was analyzed.

MATERIALS AND METHODS

Within the LIFE Child study, 434 adolescents (10 to 18 years) were included. Clinical dental examinations comprised caries experience (DMF/T-Index), signs of periodontal inflammation (probing pocket depth, PPD; community periodontal index of treatment needs; CPITN) at six index teeth and oral hygiene (OH). Information about orthodontic appliances (OA) and socioeconomic status (SES) were obtained by validated questionnaires. Test's sensitivity and specificity to detect periodontal inflammation and carious lesions were evaluated. The influence of OA on the test result was analyzed (multivariate model).

RESULTS

No associations between age, gender, SES or OH, and test outcome were found (p > 0.05). Positive test results correlated to periodontal findings (CPITN, mean PPD; p < 0.001). However, for the detection of ≥ 1 site(s) with PPD ≥ 4 mm, the test's sensitivity and specificity were found to be 61 and 69%, respectively. Multivariate analysis revealed a higher probability for a positive test result in cases of fixed OA (odds ratio 5.02, 95% confidence interval 1.90-13.19). The test had no diagnostic value considering carious lesions.

CONCLUSIONS

The chairside aMMP-8 test does not reliably identify adolescents with periodontal inflammation. Positive test results were more frequent in case of OA.

CLINICAL RELEVANCE

The chairside aMMP-8 test is no appropriate tool to screen children and adolescents neither for periodontal inflammation nor for carious lesions.

Inflammatory mediator polymorphisms associate with initial periodontitis in adolescents

Several studies have addressed cytokine gene polymorphisms and their possible associations with periodontitis. We examined the association between salivary anti- and pro-inflammatory mediator polymorphisms and initial periodontitis in Finnish adolescents, taking into account the effect of smoking. Salivary samples of 93 clinically examined adolescents from Eastern Finland were analyzed. Their oral health and smoking habits were recorded. Periodontal probing depth (PPD), and bleeding on probing (BOP) at four sites per tooth, root calculus (RC), and visible plaque index (VPI) were recorded from the index teeth. Salivary MMP-8 median values were assessed. The sites with ≥4 mm PD were categorized as follows: PPD1 = one or more ≥4 mm pocket, PPD2 = two or more ≥4 mm pockets, and PPD3 = three or more ≥4 mm pockets. Genomic DNA was extracted from 300 μl of the saliva samples by genomic QIAamp® DNA Blood Mini Kit and genotyped for polymorphisms. Genetic variants for genotyping were selected from the following genes of interest: S100A8, FCGR2A, FCGR2B, IL10, MMP8, MMP3, MMP13, VDR, TLR4, MMP2, MPO, ELANE, IL1A, IL1B, IL1RN, CD28, MMP9, DDX39B, NFKBIL1, LTA, TNF, SOD2, IL6, TLR4, TIMP1, and SYN1. After false discovery rate control (FDR), polymorphisms in MMP3 (rs679620, rs520540, rs639752), CD28 (rs3116496), and VDR (rs2228570) associated (FDR q < 0.05) with deepened periodontal pockets. Smoking did not affect the results. Genetic polymorphisms of pro-inflammatory mediators MMP3, CD28, and VDR seem to link to initial periodontitis.

Integrating oral health into pediatric nursing practice: Caring for kids where they live

PURPOSE

The purpose was to identify the factors influencing pediatric oral health and describe the Caring for Kids Where They Live program.

CONCLUSIONS

In North America, the burden of pediatric oral disease is significant. Despite evidence to this effect, oral health is an often-neglected aspect of pediatric nursing care. The Caring for Kids Where They Live program has successfully integrated oral health into pediatric nursing care as evidenced by increased accessibility of health care, pathways for care, and disease prevention.

PRACTICE IMPLICATIONS

Pediatric nurses can address oral health disparities by integrating an oral health assessment tool as well as interprofessional follow-up and referral processes in practice.

Salivary cytokines in healthy adolescent girls: Intercorrelations, stability, and associations with serum cytokines, age, and pubertal stage

Theoretically, the measurement of cytokines in saliva may have utility for studies of brain, behavior, and immunity in youth. Cytokines in saliva and serum were analyzed across three annual assessments in healthy adolescent girls (N = 114, 11-17 years at enrollment). Samples were assayed for GM-CSF, IFNγ, IL-1β, IL-2, IL-6, IL-8, IL-10, IL-12p70, TNFα, adiponectin, and cotinine. Results revealed: (1) cytokine levels, except IFNγ and IL-10, were detectable in saliva, and salivary levels, except IL-8 and IL-1β, were lower than serum levels; (2) salivary cytokine levels were lower in older girls and positively associated with adiponectin; (3) compared to serum levels, the correlations between salivary cytokines were higher, but salivary cytokines were less stable across years; and (4) except for IL-1β, there were no significant serum-saliva associations. Variation in basal salivary cytokine levels in healthy adolescent girls reflect compartmentalized activity of the oral mucosal immune system, rather than systemic cytokine activity.

Neutrophils alter epithelial response to Porphyromonas gingivalis in a gingival crevice model

A gingival crevice model (epithelial cell-Porphyromonas gingivalis-neutrophil) was established and used to profile gingipain, matrix metalloproteinase (MMP), MMP mediators [neutrophil gelatinase-associated lipocalin (NGAL) and tissue inhibitor of metalloproteinases 1 (TIMP-1)] and cytokine networks. Smoking is the primary environmental risk factor for periodontitis. Therefore, the influence of cigarette smoke extract (CSE) was also monitored in the same model. Porphyromonas gingivalis alone induced low levels of interleukin-1β and interleukin-8 from epithelial cells, but high levels of both cytokines were produced on the addition of neutrophils. Exposure to CSE (100 and 1000 ng ml(-1) nicotine equivalency) significantly compromised P. gingivalis-induced cytokine secretion (both P < 0.05). P. gingivalis induced impressive secretion of NGAL (P < 0.05) that was not influenced by CSE. The influence of CSE on gingipain production was strain-specific. Purified gingipains effectively and rapidly degraded both TIMP-1 and MMP-9. Induction of large amounts of NGAL, degradation of TIMP-1, and increased gingipain activity would each be expected to prolong collagen degradation and promote disease progression. However, gingipains also degrade MMP-9. Hence, P. gingivalis exerts a complex influence on the proteolytic balance of a gingival crevice model. Exposure to CSE reduces the proinflammatory cytokine burden, which may be expected to promote P. gingivalis survival. In addition to novel findings that provide mechanistic insight into periodontal disease progression, these results are in keeping with the recognized clinical dogma of decreased inflammation/increased disease in smokers. This straightforward gingival crevice model is established as a suitable vehicle for the elucidation of mechanisms that contribute to susceptibility to periodontitis.

Characterization of the oral fungal microbiota in smokers and non-smokers

This study aimed to assess the effect of smoking on the biodiversity of the oral fungal microbiota of healthy young subjects, using an improved culture method that assesses both total and pathogenic viable fungi. Forty individuals (20 smokers and 20 non-smokers) were selected. All individuals presented fungal growth (100% for molds and 92.5% for yeasts), a prevalence higher than previously reported. The most commonly occurring molds were Penicillium sp., Aspergillus sp., and Cladosporium sp. Smokers presented significantly higher levels of yeasts and pathogenic molds than did non-smokers. No differences in fungal prevalence and diversity were observed in smokers and non-smokers following a 30-wk observation period. In conclusion, tobacco smoking may alter the oral mycobiota and facilitate colonization of the oral cavity with yeasts and pathogenic molds. The effect of chronic fungal colonization on the oral health of tobacco smokers cannot be neglected.