The bacteria, called Fusobacterium nucleatum, can attach to colon cells and trigger a sequence of changes that can lead to colon cancer, according to the team at Case Western Reserve University School of Dental Medicine.
The researchers also found a way to prevent the bacteria from attaching to colon cells.
"This discovery creates the potential for new diagnostic tools and therapies to treat and prevent the cancer," lead investigator Yiping Han said in a university news release.
The findings show the importance of good oral health, said Han, a professor of periodontics. She noted that levels of F. nucleatum are much higher in people with gum disease.
Although the study found a possible association between oral infection and colon cancer, it did not prove a cause-and-effect relationship.
The study was published in the journal Cell Host & Microbe, which also contained another study from a different research group showing how F. nucleatum can speed the accumulation of cancer cells.
The American Academy of Family Physicians outlines how to keep your teeth and mouth healthy.