Research Digest

Passive smoking may be major cause of periodontal disease
Passive smoking, implicated in middle-ear infections and asthma in children, also may be a major cause of periodontal disease in adult non-smokers, the first study to look at this relationship has shown.

Research conducted by oral biologists in the School of Dental Medicine has shown that passive exposure to tobacco smoke may increase the risk of developing gum detachment and bleeding gums in adults by up to 70 percent.

To investigate the relationship between passive smoking and periodontal disease, Sara G. Grossi, senior research scientist, and colleagues analyzed data from 13,798 participants in the Third National Health and Nutrition Examination Survey (NHANES III), a population-based survey conducted in the U.S. from 1988-94. All participants were between the ages of 20 and 90 and had at least six natural teeth. Passive smoking was based on exposure in the home only.

Analysis of the data showed that persons exposed to passive smoking were at significantly increased risk of having more severe periodontal disease than those who were not exposed, after adjusting for age, gender, race, education, income and diabetes mellitus, important known risk factors of gum disease.

For more details, go to http://www.buffalo.edu/news/Latest/GrossiPassiveSmoke.html.

Link found between gum disease, high alcohol consumption
Oral biologists from the School of Dental Medicine have shown for the first time that heavy alcohol consumption or a diet low in antioxidant vitamins can increase the risk of developing gum disease. The research was conducted in the Periodontal Disease Research Center directed by Sara G. Grossi, senior research scientist. Both studies used data from the Third National Health and Nutrition Examination Survey (NHANES III).

For the alcohol/periodontal disease study, researchers analyzed data from 6,492 subjects between the ages of 20 and 90 selected randomly from the full sample. Persons who reported consuming alcohol from any source were divided into four groups based on consumption level, starting with five drinks per week or less and progressing to 20-per-week or more.

"As alcohol consumption increased from five drinks per week to 10, 15 and 20, the risk of periodontal disease rose from 10 percent to 20, 30 and then 40 percent," Grossi said. "When we see that kind of relationship, we know the findings are solid."

In a related study, Grossi's team examined serum levels of antioxidant nutrients and their relationship to periodontal disease, using data from 9,862 subjects between the ages of 20 and 90 who participated in NHANES III. Results showed that selenium has the strongest association with gum disease, with low levels increasing the risk by 13 fold. Low levels of vitamins A and C, a-carotene and b-crytoxanthin also increased significantly the risk of gum disease. The only antioxidant studied in which low levels were protective was lutein; Grossi said the mechanism for this relationship remains unclear.

"Clearly, low levels of most antioxidants are a risk factor for periodontal disease and infection," she said. "Free radicals are released as a result of bacteria clearance and killing. Periodontal tissue depends on natural antioxidants to overcome this oxidative stress and maintain homeostasis. When antioxidants are depleted, the ability of gum tissue to overcome oxidative stress, maintain normal tissue and control the bacterial damage appears to be compromised."

For more detail, go to http://www.buffalo.edu/news/Latest/GrossiPerioAlcohol.html.

Bacteria from gum infections linked to diabetes, lung disease
Diabetes and chronic lung disease can be added to the growing list of systemic diseases and conditions associated with bacteria from infected gums, new studies from the School of Dental Medicine have shown. To investigate the association of periodontal disease with diabetes, a research team headed by Sara G. Grossi, senior research scientist, concentrated on insulin resistance, a known precursor of active diabetes, in which cells do not absorb insulin from the blood stream.

As their study group, the researchers used 11,198 subjects from the Third National Health and Nutrition Examination Survey (NHANES III), including all non-diabetic NHANES participants between the ages of 20 and 90 who had at least six natural teeth. Results showed that those with severe periodontal disease (gum detachment), regardless of weight, have a higher index of insulin resistance than those with little or no disease.

The study on the relationship between periodontal infection and chronic lung disease was designed to follow up earlier reports of a link between poor oral hygiene, gum disease and chronic lung disease, also using data from NHANES III. Frank Scannapieco, assistant professor of oral biology, analyzed data from 13,792 adults concerning the incidence of pneumonia, asthma, bronchitis and/or emphysema and the condition of their oral health, using degree of gum detachment from bone as an indicator.

Results showed that persons with chronic lung conditions had more gum detachment than those with no lung disease, after correction for age, gender, race, ethnicity, education, income, frequency of dental visits, smoking and alcohol consumption.

For more detail, go to http://www.buffalo.edu/news/Latest/GrossiPerioChronicDis.html.