Electronic Cigarette: Role in the Primary Prevention of Oral Cavity Cancer

Electronic Cigarettes Versus Combustible Cigarettes in Oral Squamous Cell Cancer Patients: A Systematic Review

INTRODUCTION

Oral squamous cell carcinoma (OSCC) is associated with tobacco. In order to reduce the burden of smoking, e-cigarettes emerge as devices to aid cessation of tobacco addiction. However, growing evidence shows that e-cigarettes can lead to harmful effects.

OBJETIVES

The aim is to analyze the prevalence of combustible or electronic cigarette smoking in patients with a diagnosis of OSCC, analyze the prevalence of precancerous lesions in smokers of combustible or electronic cigarettes, and describe the location and differentiation of OSCC.

METHODOLOGY

PRISMA guidelines were followed. PubMed, Web of Science, and Scopus were used, introducing specific algorithms related to electronic and combustible cigarettes associated with OSCC.

RESULTS

Of 400 potentially eligible articles, 15 met the inclusion criteria: 13 studies on combustible and 2 on e-cigarettes. Regarding combustible, the mean smoking prevalence in patients was 56.38% with a prevalence of precancerous lesions of 2.50%, among other parameters. For the e-cigarette group, the mean prevalence was 4.26% with a prevalence of precancerous lesions of 2.20%. Tongue and lower lip are common and frequent locations in both cigarettes.

CONCLUSIONS

Despite certain limitations, developing OSCC is mostly associated with combustible cigarettes and to a lesser extent with e-cigarettes. Both cigarettes show a similar prevalence of precancerous lesions, with the tongue as a common and frequent location.

Oral health risks in adults who use electronic nicotine delivery systems and oral nicotine pouches: a critical review of the literature and qualitative synthesis of the available evidence

BACKGROUND

Use of combustible cigarettes (CCs) and smokeless oral tobacco products are well documented risk factors for a variety of oral diseases. However, the potential oral health risks of using recently introduced (since about 2000) non-combustible tobacco/nicotine products (NCPs: electronic cigarettes (ECs), heated tobacco products (HTPs) and oral nicotine pouches (ONPs), remain poorly established.

METHODS

This review evaluates published human studies on detrimental oral health effects in people who use NCPs compared to those smoking cigarettes and those not using any tobacco/nicotine product (NU). We identified 52 studies, predominantly focusing on adults who used electronic cigarettes as an NCP. The studies exhibited significant heterogeneity regarding design, populations, endpoints and quality. Reported outcomes, based on both single and grouped endpoints were qualitatively evaluated by comparing people who use NCPs with NU and with people smoking CCs. Significant increases (indicating a worsening in oral health), significant decreases (indicating a lower level of detrimental effects) and no significant difference between groups were assigned scores of + 1, -1 and 0, respectively. Scores from studies belonging to the same single or grouped endpoints were averaged to a summary score ranging from - 1 to + 1.

RESULTS

The qualitative meta-analysis revealed that comparisons of EC versus NU groups yielded mean scores of 0.29 for pre-cancerous lesions (N = 14 observations), 0.27 for inflammatory processes (N = 83), 0.43 for oral clinical parameters (N = 93) and 0.70 for shifts in the oral microbiome (N = 10). The corresponding values for the EC versus CC group comparisons amounted to -0.33 (N = 15), -0.14 (N = 76), -0.27 (N = 78) and 0.57 (N = 7). Most studies had significant limitations regarding group sizes, duration of NCP use (mostly only a few years) and validity of self-reported exclusive NCP use. Notably, the implications of dual use (EC + CC) and prior CC use were often not adequately considered.

CONCLUSIONS

The evaluated studies suggest that use of ECs is associated with relatively fewer detrimental oral health effects compared to smoking, yet oral health status remains poorer compared to not using any tobacco/nicotine products. These results have to be interpreted with caution due to a number of limitations and uncertainties in the underlying studies, particularly the potential biases and confounding factors inherent in cross-sectional study designs.

State of art of micronuclei assay in exfoliative cytology as a clinical biomarker of genetic damage in oral carcinogenesis: A systematic review and meta-analysis

Oral squamous cell carcinoma (OSCC) is the most common oral malignancy, often preceded by oral potentially malignant disorders (OPMDs). Currently, no clinical biomarker exists to predict malignancy, necessitating OPMD follow-up. Habits and environmental factors, such as smoking, and alcohol consumption, influence OSCC onset. Increased micronuclei (MNs) formation has been observed in the development of OSCC. Non-invasive diagnostic tests like exfoliative cytology offer painless and regular monitoring options. This study evaluates the impact of tobacco, alcohol, and pesticide exposure on MNs occurrence in exfoliative cytology-collected oral mucosal cells, assessing their potential as non-invasive biomarker for OSCC development prediction and monitoring in high-risk patients. Despite results from this meta-analysis supporting the existence of a stepwise increase from controls to patients with OPMD to OSCC, the translation of these findings into clinical practice is limited due to intra- and inter-individual heterogeneity, as well as methodological variability in MNs quantification. Various factors contribute to this heterogeneity, including demographic variables, methodological variability of different laboratories, staining techniques, sample collection location, and patient characteristics. All these points were discussed to provide further insights and improve standardization for future studies.

The Toxicological Effects of e-Cigarette Use in the Upper Airway: A Scoping Review

OBJECTIVE

While evidence continues to emerge on the negative health effects of electronic cigarettes (e-cigarettes) on the lungs, little is known regarding their deleterious effects on the upper airway. The purpose of this review is to summarize the toxicological effects of e-cigarettes, and their components, on the upper airway.

DATA SOURCES

PubMed, SCOPUS, EMBASE databases.

REVIEW METHODS

Systematic searches were performed in accordance with Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines from 2003 to 2023. Studies were included if they investigated the toxicological effects of e-cigarette exposure on human or animal upper airway tissue. Two authors independently screened, reviewed, and appraised all included articles.

RESULTS

A total of 822 unique articles were identified, of which 53 met inclusion criteria and spanned subsites including the oral cavity (22/53 studies), nasal cavity/nasopharynx (13/53), multiple sites (10/53), larynx (5/53), trachea (2/53), and oropharynx (1/53). The most commonly observed consequences of e-cigarette use on the upper airway included: proinflammatory (15/53 studies), histological (13/53), cytotoxicity (11/53), genotoxicity (11/53), and procarcinogenic (6/53). E-cigarette humectants independently induced toxicity at multiple upper airway subsites, however, effects were generally amplified when flavoring(s) and/or nicotine were added. Across almost all studies, exposure to cigarette smoke exhibited increased toxicity in the upper airway compared with exposure to e-cigarette vapor.

CONCLUSION

Current data suggest that while e-cigarettes are generally less harmful than traditional cigarettes, they possess a distinct toxicological profile that is enhanced upon the addition of flavoring(s) and/or nicotine. Future investigations into underexamined subsites, such as the oropharynx and hypopharynx, are needed to comprehensively understand the effects of e-cigarettes on the upper airway.

Current thinking about the effects of e-cigarettes on oral cancer risk

In the last decade there has been a significant increase in the appeal and popularity of e-cigarettes. Recent national news headlines outline that one million smokers will be given a free vaping starter kit to encourage them to give up tobacco products. An independent report commissioned by the UK Government has cited promotion of vaping as a critical recommendation to ensuring England is smoke-free by 2030. Undoubtedly, the dental team will now encounter many more questions from patients keen to know more regarding the safety of electronic nicotine delivery systems and their effects on the oral cavity. However, it is often difficult to answer these questions due to a lack of evidence regarding their impact. Although there are some preliminary animal and in vitro data, additional well-designed, long-term studies are required to investigate oral health outcomes of e-cigarette use.We aim to summarise the latest evidence to better inform clinicians about the effects of vaping on oral health, particularly regarding the risks of oral cancer, so they can better inform their patients.

Evaluation of Cytotoxic and Genotoxic Effects in Buccal Mucosal Cells in Non-Smokers and Users of Traditional Combustible Tobacco Products and Non-Combustible Alternatives

AIMS/OBJECTIVES

The aim of this cross-sectional observational study was to investigate cytogenetic damage to the buccal mucosa in non-smokers and consumers of traditional combustible tobacco products and non-combustible alternatives.

METHODS

A total of 160 participants were divided into four groups according to the type of product used, including non-smokers, users of conventional combustible tobacco (cigarettes), heated tobacco, and electronic, tobacco-free vapor products (e-cigarettes). Buccal mucosa samples were analyzed using the micronucleus cytome assay to assess cytotoxic and genotoxic damage.

RESULTS

E-cigarette users showed significantly higher values for all tested parameters in the micronucleus test compared to non-smokers (p < 0.05). Similarly, users of tobacco heating products showed an increase in all parameters (p < 0.05), with the exception of the number of cells with micronuclei. Conventional cigarette smokers showed a notable increase in the number of binucleated cells and cells with karyorrhexis and karyolysis (p ≤ 0.05). When assessing the differences between users of traditional combustible tobacco products and non-combustible alternatives, these did not appear to be significant, except for e-cigarette users, who had significantly more cells with condensed chromatin (p ≤ 0.001), while users of tobacco heating products had more pyknotic cells (p ≤ 0.001).

CONCLUSION

The results of this study underscore the heightened occurrence of cytotoxic and genotoxic damage in users of both conventional combustible tobacco products and non-combustible alternatives compared to non-smokers, emphasizing the detrimental impact of these products on the oral mucosa.

The use of E-cigarettes as a risk factor for oral potentially malignant disorders and oral cancer: a rapid review of clinical evidence

BACKGROUND

The popularity of e-cigarettes has increased rapidly in the last decade, particularly among teens and young adults, being advertised as a less harmful alternative to conventional tobacco products. However, in vitro and in vivo studies have evidenced a variable quantity of potentially harmful components and some recognized carcinogens which may cause DNA damage in oral cells. Additionally, evidence suggests that e-cigarettes may play active roles in the pathogenesis of other malignancies, such as lung and bladder cancers. Therefore, this rapid review aimed to assess the available clinical evidence about using e-cigarettes as a risk factor for oral potentially malignant disorders (OPMD) and oral cancer.

MATERIAL AND METHODS

A systematic search for English language articles published was performed in PubMed (MEDLINE), Embase, Scopus, and Web of Science. After the study selection process, the authors included twelve clinical studies about OPMD and oral cancer risk in e-cigarette users.

RESULTS

The main findings showed the presence of carcinogenic compounds in saliva and morphologic changes, DNA damage, and molecular pathways related to carcinogenesis in the oral cells of e-cigarette users. However, results were inconsistent compared to tobacco smokers and control groups.

CONCLUSIONS

the current clinical evidence on this topic is limited and insufficient to support using e-cigarettes as a risk factor for OPMD and oral cancer. Nevertheless, dental care professionals should advise patients responsibly about the potentially harmful effects of e-cigarettes on the oral mucosa cells. Future long-term and well-designed clinical studies are needed.

The impact of electronic and conventional cigarettes on periodontal health-a systematic review and meta-analysis

OBJECTIVES

This systematic review and meta-analysis examined the effects of electronic cigarettes on periodontal health compared to conventional cigarette smoke and a non-smoking population.

MATERIALS AND METHODS

MEDLINE, Embase, Web of Science, CENTRAL, and ClinicalTrials.gov were screened for literature. Eligibility criteria included clinical studies published between 2006 and 2022 that compare e-cigarettes and conventional cigarettes on periodontal health (bleeding on probing (BoP), plaque index (PI), probing depth (PD), attachment loss (AL), marginal bone loss (MBL), tooth loss, molecular inflammation markers, salivary flow rate). Meta-regression analysis was used to examine the influence of moderator variables.

RESULTS

Sixteen studies were found to be eligible for qualitative synthesis. Individual analyses showed that cigarette smokers had significantly higher PI, PD, AL, and MBL and increased concentrations of proinflammatory mediators than e-cigarette users and non-smokers. Meta-analysis revealed a 0.33-fold lower chance for BoP in e-cigarette users compared to smokers (p = 0.03), whereby meta-regression failed to detect any effects regarding the age of users and frequency of smoking. A 0.01-fold decreased chance for positive BoP in e-cigarette users compared with non-smokers was seen (p < 0.01).

CONCLUSIONS

The current findings suggest that that e-cigarette use might be considered a healthier alternative to cigarette smoking concerning periodontal health. Even so, harmful effects of electronic nicotine delivery system (ENDS) usage on periodontal health were seen as well. However, a definitive decision on this research question remains elusive due to the absence of randomized controlled trials.

CLINICAL RELEVANCE

Electronic cigarettes, marketed as a safer alternative to traditional cigarettes, are becoming increasingly popular. Evidence on the use of electronic cigarettes as a cessation aid and its beneficial impact compared to cigarette smoke remains inconclusive, so the analysis conducted in this review addresses a recent question of high clinical relevance.

Impact of Electronic Cigarettes on the Upper Aerodigestive Tract: A Comprehensive Review for Otolaryngology Providers

Objective

The use and effects of electronic (e)-cigarettes (e-cigs) are particularly relevant for otolaryngology providers as tobacco plays a major role in benign and malignant diseases of the upper aerodigestive tract. This review aims to (1) summarize the recent policies regarding e-cigs and important patterns of use and (2) serve as a comprehensive resource for clinical providers on the known biologic and clinical effects of e-cigs on the upper aerodigestive tract.

Data Sources

PubMed/MEDLINE.

Review Methods

We conducted a narrative review on (1) general information on e-cig use and informative findings in the lower respiratory system and a comprehensive review on (2) the effects of e-cigs on cell and animal models and the clinical implications of these products on human health as is relevant to otolaryngology.

Conclusions

Although e-cigs are likely less harmful than conventional cigarettes, preliminary research on e-cigs suggest several deleterious effects including in the upper aerodigestive tract. Due to this, there has been increased interest in restricting e-cig usage, particularly among the adolescent population, and caution in recommending e-cigs to current smokers.

Implications for Practice

Chronic e-cig use is likely to have clinical implications. It is critical for otolaryngology providers to be aware of the rapidly changing regulations and use patterns regarding e-cigs and how e-cigs influence human health, particularly with regards to the upper aerodigestive tract, to accurately council patients regarding potential risks and benefits of use.

A scoping review of studies on the health impact of electronic nicotine delivery systems

We conducted a scoping review of studies on health outcomes from electronic nicotine delivery systems (ENDS). The objective was to identify, narratively synthesize, assess the strength and quality of evidence and critically appraise studies that have reported disease end points associated with the use of ENDS. We included published literature on the health impact of ENDS from 01/01/2015 until 01/02/2020 following the PRISMA guidelines using PubMed, Embase, Scopus and Google Scholar. The database search identified 755 studies, and other sources 265; 37 studies met final eligibility criteria. Levels of evidence included 24(65%) cross-sectional, one (2.7%) case-control and six (16%) case studies, four (11%) cohort studies, one (2.7%) randomized controlled trial (RCT) and one (2.7%) meta-analysis; 27(73%) studies reported only on harms, eight (22%) reported on benefits, two (2%) on benefits and harms. Quality ratings were poor in 20 (54%), fair in 9(24%) and good in 8(22%) of studies. In our review, ENDS was not shown to be causative for harmful cardiovascular disease (CVD) outcomes and shown to be beneficial for hypertensive patients. Switching from cigarettes to e-cigarettes resulted in reduced exacerbations of chronic obstructive pulmonary disease (COPD), with no evidence of long-term deterioration in lung function. Mental Health, cancer and mortality were not adequately studied to form any consensus. Our review has not demonstrated ENDS to be causative of harmful CVD outcomes; furthermore switching from cigarettes to e-cigarettes was associated with improved hypertensive control and reduced exacerbations of COPD, with no evidence of increased asthma risk or long-term respiratory harm. Mental health, cancer and mortality outcomes have not been adequately studied to form a conclusion. Overall, the findings of our review did not provide evidence to counter the consensus held by many that ENDS use is safer than the risks posed from smoking cigarettes.

Early Diagnosis of Oral Mucosal Alterations in Smokers and E-Cigarette Users Based on Micronuclei Count: A Cross-Sectional Study among Dental Students

The presence of micronuclei in oral epithelial cells is considered a marker of genotoxicity, which can be identified using exfoliative cytology. The aim of this study was to investigate cytotoxic damage through the evaluation of micronuclei in the oral mucosa of smokers and e-cigarette users compared to nonsmokers. We obtained smears from the buccal mucosa of 68 participants divided in 3 groups (smokers, e-cigarette users and nonsmokers), which were further processed with Papanicolaou stain. The frequencies of micronuclei and micronucleated cells were recorded and statistically analyzed at a level of significance of p < 0.05. The mean micronuclei values per 1000 cells were 3.6 ± 1.08 for smokers, 3.21 ± 1.12 for e-cigarette users and 1.95 ± 1.05 for nonsmokers. The mean values of micronucleated cells per 1000 cells were 2.48 ± 0.91 for smokers, 2.39 ± 1.07 for e-cigarette users and 1.4 ± 0.68 for nonsmokers. Smokers and e-cigarette users had significantly higher values of micronuclei and micronucleated cells compared to nonsmokers, but there were no significant differences between smokers and e-cigarette users. We concluded that the micronuclei count can be used as an early indicator for alterations of oral mucosa and exfoliative cytology represents an accessible tool which could be applied for mass screening.

In vitro evaluation of the effect of the electronic cigarette aerosol, Cannabis smoke, and conventional cigarette smoke on the properties of gingival fibroblasts/gingival mesenchymal stem cells

OBJECTIVE

The current study aimed to evaluate the effect of electronic cigarette (EC) aerosol, Cannabis, and conventional cigarettes smoke on gingival fibroblast/gingival mesenchymal stem cells' (GF/G-MSCs) of never smokers.

MATERIAL AND METHODS

Human GF/G-MSCs (n = 32) were isolated and characterized using light microscopy, flow cytometry, and multilineage differentiation ability. Following the application of aerosol/smoke extracts, GF/G-MSCs were evaluated for cellular proliferation; colony-forming units (CFU-F) ability; cellular viability (using the MTT assay); mitochondrial depolarization using JC-1 dye; and genes' expression of ATM, p21, Oct4, and Nanog.

RESULTS

Colony-forming units and viability (OD 450 nm) were significantly reduced upon exposure to Cannabis (mean ± SD; 5.5 ± 1.5; p < .00001, 0.47 ± 0.21; p < .05) and cigarettes smoke (2.3 ± 1.2 p < .00001, 0.59 ± 0.13, p < .05), while EC aerosol showed no significant reduction (10.8 ± 2.5; p = .05, 1.27 ± 0.47; p > .05) compared to the control group (14.3 ± 3, 1.33 ± 0.12). Significantly upregulated expression of ATM, Oct4, and Nanog (gene copies/GADPH) was noticed with Cannabis (1.5 ± 0.42, 0.82 ± 0.44, and 1.54 ± 0.52, respectively) and cigarettes smoke (1.52 ± 0.75, 0.7 ± 0.14, and 1.48 ± 0.79, respectively; p < .05), whereas EC aerosol caused no statistically significant upregulation of these genes compared to the control group (0.63 ± 0.1, 0.31 ± 0.12, and 0.64 ± 0.46, respectively; p > .05). The p21 gene was not significantly downregulated in EC aerosol (1.22 ± 0.46), Cannabis (0.71 ± 0.24), and cigarettes smokes (0.83 ± 0.54) compared to the control group (p = .053, analysis of variance).

CONCLUSION

Cannabis and cigarettes smoke induce DNA damage and cellular dedifferentiation and negatively affect the cellular proliferation and viability of GF/G-MSCs of never smokers, whereas EC aerosol showed a significantly lower impact on these properties.

Electronic Cigarettes and Oral Health

Novel nicotine products, particularly electronic cigarettes (e-cigarettes), have become increasingly popular over the past decade. E-cigarettes are sometimes regarded as a less harmful alternative to tobacco smoking, and there is some evidence of their potential role as a smoking cessation aid. However, there are concerns about their health consequences, particularly in users who are not tobacco smokers, and also when used long term. Given the mode of delivery of these products, there is potential for oral health consequences. Over the past few years, there have been an increasing number of studies conducted to explore their oral health effects. In vitro studies have reported a range of cellular effects, but these are much less pronounced than those resulting from exposure to tobacco smoke. Microbiological studies have indicated that e-cigarette users have a distinct microbiome, and there is some indication this may be more pathogenic compared to nonusers. Evidence of oral health effects from clinical trials is still limited, and most studies to date have been small in scale and usually cross-sectional in design. Epidemiological studies highlight concerns over oral dryness, irritation, and gingival diseases. Interpreting data from e-cigarette studies is challenging, given the different populations that have been investigated and the continual emergence of new products. Overall, studies reveal potential oral health harms, underscoring the importance of efforts to reduce use in nonsmokers. However, in smokers who are using e-cigarettes as an aid to help them quit, the benefits of quitting tobacco smoking may outweigh any negative oral health impacts of e-cigarette use, particularly in the short term. Future research is needed to understand the clinical significance of some of the biological changes observed by following different cohorts of users longitudinally in carefully designed clinical studies and pragmatic trials supported by high-quality in vitro studies.

E-cig might cause cell damage of oral mucosa

OBJECTIVE

The aim of this study was to investigate cytogenetic and cytotoxic damage through the evaluation of micronuclei (MN) and metanuclear anomalies in the oral mucosa of electronic cigarette (e-cig) users.

STUDY DESIGN

The patients were recruited into 4 groups: e-cig users, smokers, former smokers, and nonsmokers (control). The samples were collected by means of exfoliative cytology of the lateral region of the tongue and the floor of the mouth. The smears obtained were fixed and stained by the Feulgen method for investigation of MN and metanuclear anomalies.

RESULTS

A significant difference was observed for MN frequency only between the smoker and control groups. As for metanuclear anomalies, significant differences were observed: karyolysis between: smokers and control, e-cig and control, as well as former smokers; karyorrhexis: between smoker and control; binucleation: between e-cig and former smoker, as well as control; broken eggs: between e-cig and all other groups; nuclear bud: between e-cig and former smokers, as well as control.

CONCLUSIONS

E-cig and alcohol users presented genotoxicity and cytotoxicity in the oral mucosa cells. The use of e-cigs and alcohol by former smokers can cause more damage to the cells of the oral mucosa compared to those who have not used e-cigs.

What should every dental health professional know about electronic cigarettes?

Electronic cigarettes (E-cigarettes) have become increasingly popular around the world. Currently, dental professionals' knowledge and attitudes are varied with many clinicians unclear regarding the impact of E-cigarette products on the oral and general health of their patients. With developing social and health-related challenges, advice of dental and medical associations and other regulatory bodies on E-cigarette use is changing. Growing evidence demonstrating the risks of E-cigarette usage has prompted a review of legislation in the United Kingdom (UK), United States of America (USA), Australia and Canada to include the sale and availability of E-cigarettes, particularly those containing nicotine. Further consideration within the scientific and public health community is being given to assessing demographic usage patterns particularly uptake by non-smokers and adolescents, efficacy as a cessation tool, the impact of vapour on bystanders and direct injuries via explosions as well as emerging lung injuries. This article aims to provide a summary of the most up to date evidence relating to E-cigarette use, the latest position of dental associations and the oral health implications of E-cigarettes compared to conventional smoking. The article also aims to collate this information in order to provide dental clinicians with guidance on how to advise patients, specifically in answering common questions posed regarding E-cigarette use.

Well-being and harm reduction, the consolidated reality of electronic cigarettes ten years later from this emerging phenomenon: A narrative review

Tobacco use is the greatest threat to public health worldwide, killing more than seven million people annually. This paper, about 10 years after the first review on electronic cigarettes, analyses the evolution that this tool has had in these years. It concludes with comments on the significance of the research and why it constitutes an original contribution. We searched PubMed (National Library of Medicine), and PsycINFO (Ovid) (2006-2020) for studies on e-cigarettes (harms and benefits, e-cigarette use, craving and smoking cessation) and smoking cessation treatment (smoking cessation treatment or varenicline or tobacco cessation or reduction or bupropion or NRT or behavioral treatment or ecigarette) and evidence suggests that they may effective as smoking cessation tool and may be less harmful alternatives to combustible cigarette smoking. Consequently, e-cigarettes could be considered as an applicable instrument for Tobacco Harm Reduction (THR) and smoking cessation.

Transcriptomic analysis of tobacco-flavored E-cigarette and menthol-flavored E-cigarette exposure in the human middle ear

Electronic cigarettes (e-cigarettes) are the most widely used electronic nicotine delivery systems and are designed to imitate smoking and aid in smoking cessation. Although the number of e-cigarette users is increasing rapidly, especially among young adults and adolescents, the potential health impacts and biologic effects of e-cigarettes still need to be elucidated. Our previous study demonstrated the cytotoxic effects of electronic liquids (e-liquids) in a human middle ear epithelial cell (HMEEC-1) line, which were affected by the manufacturer and flavoring agents regardless of the presence of nicotine. In this study, we aimed to evaluate the gene expression profile and identify potential molecular modulator genes and pathways in HMEEC-1 exposed to two different e-liquids (tobacco- and menthol-flavored). HMEEC-1 was exposed to e-liquids, and RNA sequencing, functional analysis, and pathway analysis were conducted to identify the resultant transcriptomic changes. A total of 843 genes were differentially expressed following exposure to the tobacco-flavored e-liquid, among which 262 genes were upregulated and 581 were downregulated. Upon exposure to the menthol-flavored e-liquid, a total of 589 genes were differentially expressed, among which 228 genes were upregulated and 361 were downregulated. Among the signaling pathways associated with the differentially expressed genes mediated by tobacco-flavored e-liquid exposure, several key molecular genes were identified, including IL6 (interleukin 6), PTGS2 (prostaglandin-endoperoxide synthase 2), CXCL8 (C-X-C motif chemokine ligand 8), JUN (Jun proto-oncogene), FOS (Fos proto-oncogene), and TP53 (tumor protein 53). Under menthol-flavored e-liquid treatment, MMP9 (matrix metallopeptidase 9), PTGS2 (prostaglandin-endoperoxide synthase 2), MYC (MYC proto-oncogene, bHLH transcription factor), HMOX1 (heme oxygenase 1), NOS3 (nitric oxide synthase 3), and CAV1 (caveolin 1) were predicted as key genes. In addition, we identified related cellular processes, including inflammatory responses, oxidative stress and carcinogenesis, under exposure to tobacco- and menthol-flavored e-liquids. We identified differentially expressed genes and related cellular processes and gene signaling pathways after e-cigarette exposure in human middle ear cells. These findings may provide useful evidence for understanding the effect of e-cigarette exposure.

Electronic Cigarettes and Head and Neck Cancer Risk-Current State of Art

E-cigarettes have become increasingly popular in the last decade and are considered less harmful than traditional tobacco products due to the lower content of toxic and carcinogenic compounds. However, this is still a controversial issue. This paper contains a review of previous reports on the composition of e-cigarettes and their impact on the pathogenesis and risk of head and neck cancer (HNC). The objective of the review was to compare the molecular and health effects of e-cigarette use in relation to the effects of traditional cigarette smoking in the upper respiratory tract, and to assess the safety and effect of e-cigarettes on HNC risk. A review for English language articles published until 31 August 2020 was made, using a PubMed (including MEDLINE), CINAHL Plus, Embase, Cochrane Library and Web of Science data. The authors reviewed articles on both toxic and carcinogenic compounds contained in e-cigarettes and their molecular and health effects on the upper respiratory tract in comparison to tobacco cigarettes. The risk of developing head and neck squamous cell carcinoma (HNSCC) remains lower in users of e-cigarettes compared with tobacco smokers. However, more long-term studies are needed to better address the safety of e-cigarettes.

Epidemiology of head and neck cancers: an update

PURPOSE OF REVIEW

This review attempts to give an update of epidemiological knowledge on head and neck cancers (HNC).

RECENT FINDINGS

Worldwide, from 1990 to 2017, incidence rates for larynx and nasopharyngeal cancers decreased, whereas they increased for oro/hypopharyngeal cancers and lip/oral cavity cancers. They are still markedly higher among men than women. South Asia has the highest HNC incidence rate, followed by Europe, North America, and Australasia.Tobacco and alcohol remain the major risk factors. Rate of cancers attributable to human papillomavirus (HPV) among HNCs is highly depending on world region and tobacco use prevalence. It increases in high-income countries. In the US population, the number of HPV-attributable oropharyngeal cancers now exceeds the number of cervix cancers. HPV vaccination for boys is recommended in an increasing number of countries. Many occupations are associated with an increased HNC risk. Fruits and vegetables intake have a protective effect against HNC.

SUMMARY

To decrease HNC incidence, measures to reduce tobacco use and alcohol consumption remain essential. Improvement of HPV vaccination coverage is also a major objective. Reduction of carcinogens at occupation, protection of workers from carcinogen exposures, education for better diet, and easy and affordable access to fruits and vegetables can contribute to incidence decrease.

Tobacco smoking, related harm and motivation to quit smoking in people with schizophrenia spectrum disorders

This narrative review focuses on the topic of tobacco smoking amongst people with schizophrenia spectrum disorders. We searched PubMed, PsycInfo and Scopus databases for schizophrenia spectrum disorders and smoking and included articles about the epidemiology of tobacco smoking in people with schizophrenia spectrum disorders, examining the relationship between smoking and mental health. This narrative review describes that a higher prevalence, frequency and impact of both high nicotine dependence and its harmful effects in patients with schizophrenia spectrum disorders compared with those in the general population. Despite several existent theories, the reasons for high smoking rates, the high dependence on nicotine and severity of nicotine withdrawal symptoms are not fully understood. The main aim of this paper is to inform mental health personnel and particularly clinical and health psychologists about the impact and role of tobacco smoking for smokers with schizophrenia spectrum disorders.

The oral health impact of electronic cigarette use: a systematic review

Introduction: Electronic cigarette (e-cigarette) use is becoming more prevalent and is particularly popular among adolescents and conventional smokers. While the oral health sequelae of conventional smoking are well-established, the impact of e-cigarettes on oral health is still unknown. This study aims to systematically review the available research evidence on the oral health impact of e-cigarette use.Methods: This systematic review was conducted according to PRISMA guidelines and used the Effective Public Health Practice Project Quality Assessment Tool to evaluate the evidence. Three electronic databases (PubMed, Web of Science, and Embase) were systematically searched for studies including case reports. Two independent reviewers extracted data and synthesized the findings.Results: Ninety-nine articles were included in this systematic review. Analyses of the articles yielded seven categories based on symptom similarity and/or focus: mouth effects, throat effects, periodontal effects, dental effects, cytotoxic/genotoxic/oncologic effects, oral microbiome effects, and traumatic/accidental injury. The majority of mouth and throat symptoms experienced by e-cigarette users were relatively minor and temporary, with some evidence that conventional smokers who switched to e-cigarettes experienced mitigation of these symptoms. E-cigarette exposure increased the risk for deteriorating periodontal, dental and gingival health as well as changes to the oral microbiome. Extensive dental damage as a result of e-cigarette explosions were described in case reports. Components of e-cigarette vapor have known cytotoxic, genotoxic, and carcinogenic properties.Conclusions: Although switching to e-cigarettes may mitigate oral symptomatology for conventional smokers, findings from this review suggest that a wide range of oral health sequelae may be associated with e-cigarette use. Well-designed studies to investigate oral health outcomes of e-cigarette use are needed.

Electronic Nicotine Delivery Systems (ENDS) and Their Relevance in Oral Health

The number and popularity of electronic nicotine delivery systems (ENDS) and especially e-cigarettes (e-cigs) have been increasing in the last decade. Although ENDS owe their popularity to excluding the harmful chemicals that are present in tobacco smoke, there is a debate whether they are safe, regulated, and as harmless as they are assumed to be and have potential unknown long-term effects. Involvement of cigarette smoking to the progression of periodontal diseases, other adverse oral health outcomes, and its detrimental effects to oral health are well-described. ENDS producer companies claim that these products can improve oral health by providing alternatives to smoking. However, the effect of e-cigs on oral health is not fully understood and is still debated among many scientists and clinicians. The number of studies addressing the potential toxic effect of ENDS or e-cig aerosol on oral cells is limited along with the clinical studies which are still preliminary, and their sample size is limited. The long-term effects of inhaled aerosols and the potential synergistic effect of the e-cigs components are not known. It is essential and of utmost importance to determine whether exposure to ENDS aerosol contributes to the progression of periodontal diseases and how it affects periodontal ligament and gingival cells which are believed to be its first targets. This review briefly summarizes the available evidence about the effects of e-cigs on periodontal health including several pathophysiological events, such as oxidative stress, DNA damage, inflammation, cellular senescence, dysregulated repair, and periodontal diseases.

E-cigarettes and head and neck cancers: A systematic review of the current literature

BACKGROUND

Cigarette smoking is a well-established risk factor for head and neck (HN) cancers. Use of electronic cigarettes (e-cigarettes) is gaining popularity, being advertised as benign alternatives to tobacco. A wide variety of potentially harmful chemical components with variable quantity have been identified in e-liquids and aerosols of e-cigarettes. However, use of e-cigarettes remains controversial due to conflicting evidence.

OBJECTIVES

We aimed to assess the association between e-cigarettes and HN cancers. We conducted a systematic review to evaluate the literature for evidence on carcinogenic effects of e-cigarettes in the pathogenesis of HN cancers.

TYPE OF REVIEW

Qualitative systematic review.

SEARCH STRATEGY

A PubMed/MEDLINE, Cochrane, CINAHL Plus, Trip Medical Database and Web of Science search was done for studies on e-cigarettes and HN cancer.

EVALUATION METHOD

Abstract review of all articles, full article revision of included studies, data extraction and quality assessment were performed by two independent assessors.

RESULTS

The literature search resulted in the identification of 359 articles. Eighteen articles were selected for inclusion into the systematic review. The majority were laboratory-based studies, followed by several cohort and case studies, representing low-level evidence. A few reports suggested DNA damage following exposure to e-cigarettes potentially due to increased oxidative stress. Flavoured e-liquids appear to be more harmful. There is variable evidence from clinical studies.

CONCLUSIONS

Our review outlines potential dangers associated with the use of e-cigarettes and their role in HN cancers. More longitudinal and controlled studies are needed to assess the possible link between e-cigarettes and HN cancers.

Effect of Electronic Cigarettes on the Inner Mucosa of the Craniofacial Region

OBJECTIVES

The aim of this paper is to investigate electronic cigarettes (e-cigarettes) from the otorhinolaryngologic point of view.

METHODS

The authors searched Central Database of Kirikkale University Library, Google, PubMed, and Proquest and Google Scholar.

RESULTS

An electronic cigarette or e-cigarette is a battery-powered device that vaporizes a liquid, generally including nicotine. Nowadays, e-cigarettes are used for smoking cessation or to reduce the consumption of conventional tobacco cigarettes. First generation e-cigarette devices were similar to conventional tobacco cigarettes in terms of shape and size and expressed as "cigalikes." Differently from traditional cigarettes in which tobacco is burned to generate smoke, electronic cigarettes contain a tank filled with liquid. It was found that e-cigarette liquids contained different types of chemical compounds which were either previously known carcinogens or probably prove to be carcinogenic to humans in the near future. It seems that the use of electronic cigarette does not harm the oral cells. However, the use of e-cigarette for 4 weeks led to metaplasia and hyperplasia of the laryngeal mucosa in rats. Furthermore, e-ciagarettes produce some adverse effects on the nasal mucosa, supressing the immune system.

CONCLUSION

It should not be considered that e-cigarettes are safer unless their effects on the mucosa of the ear, nose, and throat are more precisely clarified.

Electronic nicotine delivery systems: Oral health implications and oral cancer risk

There is a paucity of evidence surrounding the potential detrimental effects of electronic nicotine delivery systems (ENDS) for both systemic and oral health. The effects of conventional cigarettes on the development of oral cancer are well known; however, the role of ENDS in oral carcinogenesis is yet to be elucidated. Furthermore, the exponential rise of the use of ENDS by the general public means that dental healthcare providers are more likely to encounter questions on their safety in the oral cavity, and on their effectiveness as a smoking cessation aid. Herein, we review the most up to date literature on the systemic and oral health complications of ENDS. Moreover, evidence-based recommendations on the use of ENDS as a smoking cessation tool within the dental setting are discussed.

Electronic Cigarette Awareness, Use, and Perceptions among Cancer Patients

Objective

Electronic cigarettes (e-cigs) are an emerging trend, yet little is known about their use in the cancer population. The objectives of this study were (1) to describe characteristics of e-cig use among cancer patients, (2) to define e-cig advertising exposure, and (3) to characterize perceptions of traditional cigarettes versus e-cigs.

Study Design

Cross-sectional study.

Setting

Comprehensive cancer center.

Subjects and Methods

Inpatient, current smokers with a cancer diagnosis. E-cig exposure and use were defined using descriptive statistics. Wilcoxon rank test was used to compare perceptions between e-cigs and traditional cigarettes.

Results

A total of 979 patients were enrolled in the study; 39 cancer patients were identified. Most cancer patients were women (59%), with an average age of 53.3 years. Of the patients, 46.2% reported e-cig use, most of which (88.9%) was “experimental or occasional.” The primary reason for e-cig use was to aid smoking cessation (66.7%), alternative use in nonsmoking areas (22.2%), and “less risky” cigarette replacement (5.6%). The most common sources for e-cig information were TV (76.9%), stores (48.7%), friends (35.9%), family (30.8%), and newspapers or magazines (12.8%). Compared with cigarettes, e-cigs were viewed as posing a reduced health risk (P < .001) and conferring a less negative social impression (P < .001). They were also viewed as less likely to satisfy nicotine cravings (P = .002), to relieve boredom (P = .0005), to have a calming effect (P < .001), and as tasting pleasant (P = .006)

Conclusions

E-cig use and advertising exposure are common among cancer patients. E-cig use is perceived as healthier and more socially acceptable but less likely to produce a number of desired consequences of cigarette use.

Oral mucosal lesions in electronic cigarettes consumers versus former smokers

OBJECTIVES

Electronic cigarettes (ECs) have become very popular in recent years. However, many uncertainties remain about their side effects. This study aims to evaluate the prevalence and characteristics of oral mucosal lesions (OMLs) in former smokers compared to ECs consumers.

METHODS

A prospective case-control study was carried out. Outpatients for dental consultation were consecutively enrolled into two groups based on their habits, i.e. former smokers and ECs consumers. Each patient was examined to detect possible oral lesions and, if needed, a swab or biopsy of the lesion was taken for diagnosis. Data was entered into a spreadsheet and analyzed.

RESULTS

A total of 90 patients were examined, 45 were former smokers (group A) and 45 were ECs consumers (group B). OMLs were detected in 55 cases, of which 19/55 (34.6%) belonged to group A and 36/55 (65.4%) to group B. Nicotine stomatitis, a hairy tongue and angular cheilitis resulted to be significantly more common among EC consumers.

CONCLUSIONS

We found no statistically significant differences in terms of total prevalence of OMLs between former smokers and ECs consumers. An increased prevalence of three specific types of OMLs was detected among ECs consumers.

Patterns of concurrent cigarette, alcohol, and e-cigarette use: Off-setting or additive behaviors?

OBJECTIVES

To understand nationwide concurrent use of e-cigarettes (Ecig) with alcohol and conventional cigarettes (Ccig), the major risk factors for head and neck cancer.

STUDY DESIGN

Cross-sectional analysis of nationally representative survey.

METHODS

The National Health Interview Surveys for 2014 and 2015 were analyzed for adult responses to specific questions regarding the daily frequency of alcohol, Ccig, and Ecig use. Statistical relationships between these social habits were determined.

RESULTS

A total of 241.1 million adults (raw N = 162,048) were surveyed (mean age 47.1 years, 51.8% female). Of those, 12.1% (29.2 million) and 3.8% (9.08 million) reported being every day Ccig users and some days Ccig users, respectively. A total of 2.3% (5.63 million) and 1.1% (2.76 million) reported being every day Ecig users and some days Ecig users, respectively. In addition, 58.4% of everyday Ecig users reported also being everyday Ccig users (P < 0.001). Furthermore, 25.6% (61.3 million) and 8.3% (20.0 million) of adults reported light drinking (1-3 drinks/week) and moderate/heavy drinking (4-7 drinks/week), respectively. Of the moderate/heavy drinkers, 17.7% were everyday Ccig users, whereas 12.2% of everyday Ccig users were moderate/heavy drinkers (P < 0.001). Among everyday Ecig users, 34.6% and 11.2% were light drinkers and moderate/heavy drinkers, respectively (P < 0.001). Among non-Ccig users, everyday Ecig users were likely to consume higher levels of alcohol given that 36.5% and 8.9% were light drinkers and moderate/heavy drinkers, respectively (P < 0.01).

CONCLUSION

We demonstrate a substantial level of Ccig use among moderate/heavy drinkers and Ecig users, as well as a novel independent association between Ecig and moderate/heavy alcohol use. These patterns of concurrent risk factor exposure should be considered when counseling patients who report Ecig use.

LEVEL OF EVIDENCE

2b. Laryngoscope, 1817-1821, 2018.

Electronic cigarettes—A review of the physiological health effects

Electronic cigarettes (ECs) are devices that are used recreationally or as smoking cessation tools, and have become increasingly popular in recent years. We conducted a review of the available literature to determine the health effects caused by the use of these devices. A heating element in the EC aerosolizes a solution of propylene glycol, glycerol, nicotine (optional), and flavouring (optional). These compounds are generally harmless on their own. However, upon heating, they produce various carcinogens and irritants. We found that concentrations of these toxicants vary significantly depending on the type of EC device, the type of EC liquid, and the smoking behaviour of the user. Exposure to these vapours can cause inflammation and oxidative damage to in vitro and in vivo cells. EC aerosol can also potentially affect organ systems and especially cardiovascular and lung function. We concluded that EC use causes acute effects on health but not as severe as those of conventional cigarettes (CCs). These devices could, therefore, be of use for smokers of CCs wishing to quit. However, as EC aerosol introduces new toxicants not found in CCs, long-term studies are needed to investigate possible chronic effects associated with EC use.