How Clear Aligners Influence the Mouth’s Bacterial Environment

Researchers at ADA Forsyth are investigating how wearing clear aligners alters the oral microbiome. These custom plastic trays, worn for most of the day over a one- to two-year orthodontic treatment, restrict the natural flow of saliva that typically cleanses teeth and controls bacterial growth ADA News.

A new study from ADA Forsyth delves into this distinct microbial habitat, aiming to translate findings into improved strategies for orthodontic patient care ADA News.

Led by Dr. Tingxi Wu (D.D.S., Ph.D.), an orthodontist and faculty member at ADA Forsyth, the NIH-funded study focuses on the role of three bacterial species in gingival inflammation associated with clear aligner use ADA News.

Clinical observations revealed that patients developing gingivitis while using aligners exhibited elevated levels of:

• Saccharibacteria (also known as TM7)

• Fusobacterium nucleatum (F. nucleatum)

• Schaalia odontolytica (S. odontolytica)

Dr. Wu notes that their presence together points to a potential cooperative role in driving inflammation: “These three species are abundant in gingivitis patients wearing clear aligners, which suggests they may work together to progress inflammation,” she says. “Can we figure out how exactly they work together? The answer could bring us new ideas about how to treat and prevent gum disease.” ADA News

Prior research indicates that Saccharibacteria form an episymbiotic relationship by attaching to S. odontolytica. It’s suspected that this pairing interacts with the opportunistic pathogen F. nucleatum—commonly linked to periodontitis ADA News.

While earlier ADA Forsyth studies examined Saccharibacteria's potential role in limiting periodontitis, they did not explore how it might collaborate with other bacterial species ADA News.

By mapping how these three bacteria interact in the aligner-altered oral environment, the researchers aim to design targeted interventions to maintain gum health during orthodontic treatment ADA News. Dr. Xuesong He (D.D.S., Ph.D.), a collaborator on the project, adds, “Once we have a better understanding of how certain bacteria on the surface of teeth interact with each other and contribute to disease, we can form an approach to mitigate their effects.” ADA News