Even Short-term Vaping May Promote Oral Disease

Diana Swift

May 28, 2020

Clinicians have been worried that vaping can cause pulmonary damage. Now researchers report that vaping — even for a few months — can push healthy mouths toward serious periodontal disease.

In the first human study of vaping's impact on the oral cavity, the researchers found this electronic drug-delivery system negatively alters the microbial ecosystem of the mouth, creating an ideal breeding ground for pathogenic bacteria whose damaging reach extends beyond the mouth to the cardiovascular system.

"E-cigarettes increase risk for oral diseases by shifting health-compatible ecosystems to virulence-rich communities," the authors write.

Sukirth M. Ganesan, BDS, PhD, and colleagues from The Ohio State University in Columbus, report their findings in an article published online May 27 in Science Advances. Ganesan is currently an assistant professor in the Division of Periodontology at the University of Iowa in Iowa City.

The researchers studied immunoinflammatory responses and microbial dynamics in the oral ecosystems of 123 systemically and periodontally healthy individuals ranging in age from 21 to 35 years. They examined subgingival plaque samples from five groups within the 123 participants: 25 current smokers, 25 nonsmokers, 20 e-cigarette users, 25 former smokers turned vapers, and 28 simultaneous cigarette smokers and vapers.

Those vaping for at least 3 months had pathogen overgrowth, higher microbial virulence signatures, and a robust proinflammatory signal — changes resembling those in patients with severe periodontitis. Even longtime current and former smokers of conventional cigarettes had worsened oral profiles after 3 to 12 months of vaping, suggesting the pathogenetic mechanisms triggered by vaping may differ from those triggered by smoking.

Although e-cigarettes have been presented as a strategy to reduce combustible tobacco harms, these findings counter claims that vaping is a safe alternative to smoking. "If you stop smoking and start vaping instead, you don't move back toward a healthy bacterial profile but shift up to the vaping profile," senior author Purnima S. Kumar, BDH, PhD, a professor of periodontology at The Ohio State University in Columbus, said in a news release. "Knowing the vaping profile is pathogen-rich, you're not doing yourself any favors by using vaping to quit smoking."

The authors say the oral cavity harbors more than 700 microbial species, with oral health depending on stable health-compatible bacterial communities. Destabilization of this environment triggers a fulminant disease-promoting inflammatory response.

The most notable effect of vaping chemicals was their alteration of oral biofilm architecture. "[T]he nicotine-free aerosol consisting of glycerol and glycol, viscous sugar alcohol fluids that generate the cloud when vapers exhale, functioned as a nutrition source to fuel the altered oral environment," the authors explained in the news release.

Moreover, as the damaging effects were seen with or without nicotine, these heated and pressurized liquids in e-cigarette cartridges are the main culprits in microbial shifts leading to oral dysbiosis, the researchers believe. Previous research has found that vaping harms vasculature even in the absence of nicotine.

E-cigarettes cause stress in the subgingival environment, the authors explain, which was clear from the significantly greater abundance of genes regulating the stress response in the human metagenome that emerged with vaping exposure.

"Further, longitudinal studies, preferably in humans or animal models using an oral mode of exposure to e-cigarette vapor, are urgently needed to understand the manifold effects of these drug delivery devices on human health," the authors write.

Other clinical evidence suggests e-cigarette users have worse periodontal health than nonsmokers, Chun-Teh Lee, DDS, DMSc, MS, director of periodontics research at the University of Texas Health Science Center at Houston School of Dentistry, told Medscape Medical News. "However, since many vapers are young or just started vaping a few years ago, we may not see immediate and significant harm to their oral and periodontal health," said Lee, who was not involved in the current study.

"But these results show that since e-cigarette smokers have more harmful bacteria and stronger inflammatory responses than nonsmokers, they may well have periodontal disease in the future," Lee said. In the meantime, their periodontal health might not currently be as bad as that of long-time smokers.

According to the authors, among the 6% of Americans who use e-cigarettes, some 3 million are teenagers, but Lee believes age alone is not a problem. "It's about how long, how often, and how much you use," he said.

This work was supported by the National Institutes of Health and the US Food and Drug Administration. The authors and Lee have disclosed no relevant financial relationships.

Sci Adv. Published online May 27, 2020. Full text


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.