Background: The increased use of e-cigarettes represents an emerging concern for dental practitioners with the potential to impact clinical care. The concerns for, and effects of, e-cigarettes remain poorly understood, especially with long-term use. Given current limits to our understanding of the effects of e-cigarette use, the goal of this study was to assess the level of concern among dental practitioners and the effects of these concerns on the care provided for patients using e-cigarettes. Methods: Dental practitioners (n=187) in Maryland completed a 28-item survey of e-cigarette knowledge, perception and their current clinical practices for patients using e-cigarettes. A knowledge score was computed, and associations between participant demographic characteristics and knowledge survey items, perception survey items and knowledge score levels, and behavior survey items and knowledge score levels were explored. Results: Most practitioners do not see or do not ask patients about E-cigarette use (33%), switching from conventional cigarette to E-cigarette use (38%) or dual use (55%). Majority of practitioners classified as medium to high knowledge 75% (141/187), felt they were well-informed and have up to date knowledge about E-cigarettes compared to 25% classified as low knowledge (46/187). Practice behaviors were not significantly different across knowledge score groupings. High knowledge groups modified their practice behavior positively in all the categories, except high knowledge group did not feel concerned with recommending dental implants in e-cigarette smokers (mode=5). Low knowledge group consistently had negative practice behavior except more positive response within the group for recommending stopping of E-cigarettes before invasive procedures was observed (mode = 5). Conclusions: The evidence and knowledge about e-cigarette risks on oral health is lacking and is not yet fully influencing practice behaviors. This study reinforces the value of disseminating and translating this evidence to dental practitioners through early inclusion of this topic in dental and hygiene training programs and through continuing education courses.