Periodontal disease develops much earlier than dentists and other health professionals thought

Periodontal disease -- a progressive, eventually painful and disruptive condition in which bacteria attack gums and the hidden roots of teeth -- develops much earlier than dentists and other health professionals thought, a major new study concludes.

Clinicians found a significant proportion of young adult patients examined had well-established periodontal disease despite no signs or symptoms. Affected pregnant women faced more than twice the risk of preterm birth and other pregnancy complications as unaffected women, the research also revealed.

Data from the unique set of clinical studies, conducted at the universities of North Carolina at Chapel Hill and Kentucky were released Tuesday (Sept. 20) at a news conference during the annual meeting of the American Association of Oral and Maxillofacial Surgeons in Boston.

As part of a continuing group of related investigations, the research is the first in-depth look over time at the condition in wisdom teeth -- the four rearmost teeth in the head and jaw, also known as third molars -- in young adults.

"About seven years ago, we were asked to spearhead a series of clinical trials to look at what happens if you keep your wisdom teeth and what happens if you have them taken out," said study leader Dr. Raymond P. White Jr., former dean and Dalton L. McMichael professor of oral and maxillofacial surgery at the UNC School of Dentistry.

"Part of the reason was that research at UNC and elsewhere showed that the inflammation in the mouth that periodontal infections cause promoted inflammation in other parts of the body, which contributed in significant ways to coronary artery disease, stroke, kidney disease and obstetric complications," White said. "Another reason was that there has been an increased emphasis on evidence-based medicine over the past decade or so."

The team collected baseline data on about 400 people who planned to keep their wisdom teeth. Researchers now have more than two years of follow-up information on 254 of them and plan to continue the work for at least five years.

"That a quarter of patients in their 20s had periodontal problems with no symptoms was a surprise to us since most people assumed that you don't get periodontal problems until you are 35 or 40," White said. "But nobody had looked at wisdom teeth systematically before in a large study like this."

In the evaluation of data from 1,020 higher-risk obstetrics patients enrolled in a National Institutes of Health-sponsored clinical trial, 18 percent delivered preterm, he said. Wisdom teeth were a major contributor to the young women's periodontal disease, and the severity of their disease clearly corresponded with the risk of preterm delivery. It also corresponded with indicators of systemic inflammation, such as elevated C-reactive protein, a substance produced by the liver in response to inflammation anywhere in the body.

Women with the worst periodontal disease around their 3rd molars had more than twice the risk of preterm birth, researchers found. The danger to pregnant women was comparable to the risks of smoking during pregnancy, the surgeon added. Since untreated periodontal disease in effect "seeds" the bloodstream with disease-causing bacteria, it's important that dentists, obstetricians and other physicians assess wisdom teeth when examining young adults, he said.

"Although most people eventually will develop pathology with wisdom teeth, periodontal disease, pericoronitis or tooth decay, it is too early to recommend strongly that everyone has their wisdom teeth removed," White said. "It is a good idea to have your 3rd molars evaluated before age 25. But since a quarter of people will never have problems with them, a lot depends on how risk-averse one is as to whether their third molars with no detected pathology should be extracted as a precaution."