A study published in the journal Cancer Prevention Research found that poor oral health could be a risk factor for developing oral HPV, or human papilloma virus. Once contracting HPV, a person's risk for developing cancer may be higher, the study reports.

The study, conducted by the University of Texas Health Sciences Center in Houston, examined some 3,400 people over the age of 30. People who had poor oral health and hygiene had a 56 percent higher rate of being infected with HPV compared to those in good oral health. Gum disease made the risk of contracting HPV even higher.

HPV is most often associated with sexually-transmitted diseases, and its link to cancer has only become clear in the past few years. But “the most dangerous aspect of the human papilloma virus is its potential to cause cancer,” the Oral Cancer Foundation states on its website.

"In the U.S., there is an active shift going on," Dr. Maura Gillison, a professor at the Ohio State University, told TIME. "Fortunately thanks to tobacco policy and public-health awareness, the incidence rate for the classical head and neck cancer caused by smoking is declining. But unfortunately, the rate of oropharynx cancer is still going up and it's because of the HPV component."

The Centers for Disease Control and Prevention notes that HPV is linked to several types of cancers, including cervical, vulvar, vaginal, and oral cancer. The CDC also states that when HPV remains for a period of years, it is more likely to cause cancer. About 20,000 HPV-associated cancers occur in women, and 12,000 in men.

Other studies will need to be completed before oral health can be linked to cancer with certainty. 

“What we think might be happening is if you have poor oral health — ulcers, gum inflammation, sores or lesions, any openings in the mouth — that might provide entry for HPV,” Christine Markham, an author of the paper, told the New York Times. “We don’t have sufficiently strong evidence to demonstrate that conclusively in the study, but that’s our thinking.”

Aimée R. Kreimer called the finding a “modest association,” the New York Timesreported. “We don’t know if poor oral health causes HPV infection and would go on to cancer,” she said.