Association Between E-Cigarette Use (Vaping) and Oral Health in Adolescents and Young Adults: A Systematic Review

Background: Vaping has become one of the most prevalent risk behaviors among adolescents and young adults worldwide. Although electronic cigarettes (ECs) are often perceived as safer than conventional tobacco, concerns regarding their impact on oral health are increasing. This systematic review aimed to critically evaluate and synthesize the available evidence regarding the association between e-cigarette use and oral health outcomes in adolescents and young adults. Methods: A systematic search of PubMed/MEDLINE, EMBASE, Scopus, and EBSCOhost databases was conducted for observational studies published within the last ten years. Studies evaluating oral health outcomes among adolescents and young adults were included. Risk of bias was assessed using the Joanna Briggs Institute Critical Appraisal Tool for Analytical Cross-Sectional Studies, and certainty of evidence was graded using the GRADE approach. Results: Eight observational studies met the inclusion criteria and were included in the qualitative synthesis. E-cigarette use was associated with increased caries risk, higher prevalence of gingival inflammation, alterations in salivary flow and pH, changes in oral microbiota—including increased levels of Porphyromonas gingivalis—and elevated frequencies of micronuclei in oral mucosal cells. Four studies were rated as having low risk of bias and four as moderate risk. The overall certainty of evidence was low for all outcomes due to methodological limitations, heterogeneity in outcome assessment, and inadequate control of confounding factors, including dual use of combustible tobacco products. Conclusions: Current evidence may suggest a possible association between e-cigarette use and adverse oral health alterations in adolescents and young adults. However, given the low certainty of evidence, residual confounding, and the predominance of cross-sectional designs, causal relationships cannot be established. Well-designed longitudinal studies that clearly differentiate exclusive e-cigarette users from dual users and adequately adjust for behavioral confounders are required to clarify the independent impact of vaping on oral health in this vulnerable population.