Correlation of exposure to environmental tobacco smoke and periodontitis in passive smokers; a systematic review

Introduction: Smoking is a major health hazard. Cigarette smoke is produced by burning of complex organic compounds that include highly toxic components. Passive smokers are non-smoker individuals that are exposed to second-hand smoke (SHS) or environmental tobacco smoke (ETS). Passive or involuntary smoking is currently a major public health dilemma worldwide. Considering the increasing number of passive smokers in today's world, it is imperative to assess the potential adverse effects of passive smoking on oral health and periodontal tissue. Objectives:This study aimed to assess the correlation between exposure to ETS and periodontitis in passive smokers. Methods: In this systematic review, the Google Scholar, PubMed and Scopus databases were searched for relevant articles published from 1990 to 2020. The extracted data were tabulated. Results: Search of the literature yielded 77 articles based on the searched keywords. After assessing the abstracts and excluding the duplicates, 68 articles remained. After accurate assessment by the examiners, 21 articles were selected for the full-text review. Finally, seven eligible articles remained in the study for the final review. Conclusion: Cigarette smoke affects the immune system and aggravates periodontal destruction as such. Despite the available evidence regarding the correlation of periodontal parameters and exposure to ETS in passive smokers, more comprehensive studies on this topic are still required to achieve a definite therapeutic protocol considering the small number of available studies on this topic, methodological flaws and the existing controversies.