Clinical Biomarkers to Evaluate Next Generation Inhaled Tobacco Products’ Effect in the Oral Cavity: a Narrative Review

Purpose of Review Biomarkers in the oral cavity of users of next generation tobacco products, such as electronic cigarettes (EC), provide data about effects on oral and systemic health and help predict long-term health effects, such as cardiovascular, respiratory, and periodontal disease. Despite oral cavity health provides, translation of findings to regulatory outcomes around EC is lacking. A review of the current state of the art in use of clinical biomarkers of the oral cavity was conducted. This identified inconsistencies and gaps in tobacco regulatory science to address how to improve clinical studies for screening tobacco products and studying disease. Recent Findings The review identified that saliva and buccal biopsies provide dependable biomarkers of oral and systemic health when several parameters of health are standardized and considered. Inflammatory cytokines in oral tissue and biofluids of EC users are conflicting due to differences in sample collection and analysis techniques. Salivary C-reactive protein levels provide information about systemic inflammation and risk of cardiovascular disease, but analysis of this biomarker in the oral cavity does not appear in the current literature. The oral microbiome plays a significant role in human health and may be a useful tool to study systemic effects of tobacco products non-invasively, yet inconsistencies in reporting metrics make studies difficult to compare or translate into tangible outcomes. Effects of tobacco product use on hard dental tissue are not widely investigated despite correlations observed between e-cigarette use and broken teeth. Summary This review provides a comprehensive update on clinical biomarkers in systemic and oral diseases associated with emerging nicotine products.