The impact of e-cigarette use on periodontal health: a systematic review and meta-analysis

www.nature.com/ebd ARTICLE OPEN The impact of e-cigarette use on periodontal health: a systematic review and meta-analysis Rajpal Tattar1, Joshua Jackson 2,3 and Richard Holliday 2,3 ✉ © The Author(s) 2025 KEY POINTS ● ● ● 1234567890();,: ● Studies conducted within this field are at high risk of bias (usually due to cofounding factors) and so caution must be applied to the conclusions generated There is evidence to suggest that ENDS use had some impacts on periodontal parameters compared to non-smokers/former smokers. Tobacco smokers had consistently worst outcomes. There was no evidence of a difference between ENDS users and non-smokers/former smokers in markers of periodontal destruction (pocket probing depths/marginal bone loss) Further well-designed research is required in this field to inform clinical practice and guidelines BACKGROUND: Electronic Nicotine Delivery Systems (ENDS, e-cigarettes) are a popular alternative to traditional tobacco smoking. Objective: To evaluate the effect of ENDS use on periodontal health. METHODS: A protocol was published in accordance with PRISMA standards. Subjects with periodontal health, gingivitis and periodontitis were included. Reviews, case reports, letters, abstracts, narratives and expert opinions were excluded. Databases searched included PubMed, Embase, Web of Science, CINAHL Plus, and Dentistry & Oral Sciences Source up until February 2024. Risk of bias was evaluated using the Newcastle-Ottawa Scale, ROBINS-I and the RoB 2 tools. RESULTS: 40 eligible studies were included. Smokers had poorer clinical outcomes than ENDS users and non-smokers/former smokers, apart from bleeding on probing and gingival indices. There was no difference between ENDS users and non-smokers/ former smokers in markers of periodontal destruction (pocket probing depths/marginal bone loss). ENDS users had higher plaque scores than non-smokers/former smokers. ENDS use leads to unique microbial changes compared to tobacco smokers and higher pro-inflammatory markers compared to non-smokers/former smokers. CONCLUSION: Within the limitations of the included studies which are at high risk of bias, we found evidence that ENDS use had some impact on periodontal parameters compared to non-smokers/former smokers. Tobacco smokers had consistently worst outcomes. REGISTRATION PROSPERO 2024: CRD42024496560. Evidence-Based Dentistry (2025) 26; https://doi.org/10.1038/s41432-025-01119-6 INTRODUCTION In recent years, electronic cigarettes (referred to as ENDS [Electronic Nicotine Delivery Systems] hereon) have become a popular alternative to traditional tobacco smoking. They are reported as less harmful due to the absence of combustion and many toxicants. Periodontal health is fundamental to both oral and systemic wellbeing, with disturbances potentially leading to conditions such as gingivitis, periodontitis, and eventual tooth loss. Traditional tobacco smoking is well known to harm periodontal tissues1. However, the effects of ENDS are still being studied. ENDS expose periodontal tissues to aerosolized nicotine and chemicals, which may affect oral health differently than tobacco smoking. Given the growing popularity of ENDS, especially among younger people, further research is needed to understand any effects on oral health and to guide public health initiatives and clinical guidelines. There have been several previous narrative reviews, systematic reviews and meta-analysis investigating the impact of ENDS use 1 on periodontal health2–8. Their conclusions have ranged from ENDS causing ‘increased destruction of the periodontium leading to the development of disease’ to periodontal parameters being similar among non-smokers and END users. Most systematic reviews have conducted a risk of bias or quality assessment of the included studies (Table S4, supplementary materials). Although well-known tools are often used for this assessment the main methodological issue in this field (confounding from tobacco smoking) has not previously been addressed apart from in discussion. ENDS users are often current or former tobacco smokers making it hard to differentiate the impact of ENDS use alone on the outcomes of interest and resulting in misleading conclusions. In this review we plan to assess the included studies on this issue. This review takes a comprehensive approach to assessing the effects of ENDS use on periodontal health, unlike previous reviews that focused on single outcomes. It evaluates patient-reported outcomes, clinical parameters, oral microbiome changes, and The School of Clinical Dentistry, University of Sheffield, Sheffield, UK. 2School of Dental Sciences, Faculty of Medical Sciences, Newcastle University, Newcastle Upon Tyne, UK. Newcastle Upon Tyne Hospitals NHS Foundation Trust, Newcastle Upon Tyne, UK. ✉email: 3 Received: 6 October 2024 Accepted: 20 January 2025 Published online: 13 February 2025 2 Identification Studies from databases/registers (n = 1464) PubMed (n = 495) CINAHL Plus, Denstry & Oral Sciences Source (n = 294) Web of Science (n = 291) Embase (n = 225) MEDLINE (n = 158) Expert knowledge (n = 1) References removed (n = 444) Screening Duplicates idenfied manually (n = 3) Duplicates idenfied by Covidence (n = 441) Studies screened (n = 1020) Studies excluded (n = 954) Studies sought for retrieval (n = 66) Studies not retrieved (n = 0) Studies assessed for eligibility (n = 66) Studies excluded (n = 26) Included Review arcle (n = 3) Incorrect outcomes (n = 3) Incorrect study design (n = 1) Review arcle/leer (n = 3) Full text not available (n = 11) Incorrect paent populaon (n = 5) Studies included in review (n = 40) Included studies ongoing (n = 0) Studies awaing classificaon (n = 0) Fig. 1 Study flow diagram. immunological responses. By synthesising current evidence, this review aims to elucidate any evidence on the relationship between ENDS use and periodontal health. MATERIALS AND METHODS This systematic review, registered with PROSPERO (ID CRD42024496560) on 1st March 2024, adheres to the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines9. It examines the impact of ENDS on individuals with healthy periodontium, gingivitis, or periodontitis. The primary outcomes analysed were changes in periodontal parameters (Pocket Probing Depth, PPD; Marginal Bone Loss, MBL; Clinical Attachment Level, CAL; Gingival Indices, GI; Bleeding on Probing, BOP; and plaque indices, PI), while secondary outcomes included Patient Reported Outcome Measures (PROMS), microbiological changes, and levels of biological markers. The review included observational and interventional studies restricted to human subjects and English-language publications. Evidence-Based Dentistry (2025) 26 3 Fig. 2 Forest plot of Pocket Probing Depth (PPD) comparisons for cross-sectional data: sub-grouped by risk of tobacco smoking confounding in ENDS group. A ENDS users verses non-smokers/former smokers. B ENDS verse (...truncated)