By M.R. Kropko
The Associated Press

CLEVELAND - Dental researchers have found what they believe to be a link between obesity and frequency of gum disease in people 18 to 34 years old.

Dr. Nabil F. Bissada, chairman of the Case Western Reserve University's School of Dentistry, conducted the study with researchers from the university's medical school. Findings were published in the May issue of the Journal of Periodontology.

Although the research indicates that excessive weight "is a potential risk factor" for periodontal disease in young adults, exactly why remains unclear and is the subject of research, Bissada said Wednesday.

Information was obtained from a database of 13,665 people who participated in a national health survey from 1988 to 1994.

Bissada said gum disease occurred 76 percent more often among 18- to 34-year-olds who are considered obese rather than having a normal weight. Weight classification was based on a complex scale involving kilograms and meters.

No significant link was found between body weight and periodontal disease in older age groups, Bissada said.

"The frequency of periodontal disease among older groups is more common, so the effect of weight is diluted," he said.

Diet was not included in the evaluation.

"Diet is the underlying reason why the obese have more periodontal disease, but there are several other possible explanations," said Mohammad Al-Zahraini, a dentist and periodontal researcher who helped in the study.

The National Institute of Dental and Craniofacial Research, part of the National Institutes of Health in Bethesda, Md., on its Web site lists several risk factors for periodontal disease, but not excessive weight.

Gum disease risk factors listed are smoking, hormonal changes, diabetes, stress, medications, illnesses and genetic susceptibility. The institute points out that good dental hygiene helps control bacteria that can cause gum disease.

The NIDCR says periodontal diseases range from gum inflammation, or gingivitis, to serious damage to the soft tissue and bone that support the teeth. In periodontitis, infected gums pull away from the teeth.

Dental health researchers at the University of North Carolina at Chapel Hill in May published research that found gum disease appears to contribute to dangerous hardening of the arteries.

Dr. Bruce Gerbach, a general practice dentist in the Cleveland suburb of Mentor and public service chairman for the Ohio Dental Association, said he hasn't seen a direct link between overweight young adults and gum disease.

"I would say young, obese people are more likely to be diabetic, and for years it's been known that people who are diabetic are more susceptible to gum disease."

He said young adults, no matter what their weight, tend to be more likely to put off dental visits and drink more soft drinks, making them susceptible to gum disease.