UB Study Finds Test to Find Antigens to Be Effective

BUFFALO, N.Y. -- A five-minute test designed for use in the dentist's office to determine the presence of antigens from three major bacteria found in localized juvenile periodontitis (LJP) gets high marks for accuracy, according to a study by researchers at the University at Buffalo.

The EVALUSITE Periodontal Test also could be used to detect bacteria prevalent in the adult form of the disease, says Sara G. Grossi, D.D.S., assistant professor of oral biology and principal investigator on the study.

Grossi presented the findings of her research on the EVALUSITE Test recently at the general meeting of the International Association for Dental Research in Seattle.

The EVALUSITE Test measures the antigens for Actinomyces actinomycetemcomitans, Porphyromonas gingivalis and Prevotella intermedia, the three major bacteria present in LJP. EVALUSITE is the only chairside test available. The presence of antigens previously was determined through culture.

In the UB study, measurements of the pocket depth at 16 gum sites and samples of subgingival plaque were take from 16 patients ages 10 to 25.

Sites with a pocket depth of 5 mm or greater were labeled diseased; those of 4 mm or less were labeled healthy. Loss of attachment (LOA) of tooth-supporting tissue also was measured, with a LOA of 3 mm or less rated as healthy and a LOA of 4 mm or greater labeled diseased.

Researchers found a marked difference in the presence of antigens for the three bacteria in healthy vs. diseased areas when using the EVALUSITE Test. The test showed that the higher the numbers for the bacterial antigens, the deeper the pockets and the greater the LOA.

The prevalence of A. actinomycetemcomitans was found to be 12.5 percent for diseased areas compared to 3.4 percent for healthy areas. The incidence of P. gingivalis was 27.5 percent for diseased areas compared to 11.8 percent in healthy areas. And the prevalence of P. intermedia was 37.5 percent for diseased areas vs. 14.3 percent for healthy.

The EVALUSITE Test is currently marketed in Canada and some European countries, but is not yet available in the United States. It has been used in more than 300 patients, with more than 4,000 samples being collected.

In addition to Grossi, other members of the research team are Brian Snyder, Ph.D., research scientist, and Carol Ryerson, Ph.D., director of clinical trials, both at Eastman Kodak Co.; Robert Dunford, a UB biostatistician, and Robert J. Genco, D.D.S., chair and distinguished professor in the UB Department of Oral Biology.

The study was funded by the U.S. Public Health Service and Eastman Kodak Co.