July 7 (HealthDay News) -- A syrup containing the sugar substitute xylitol helps prevent tooth decay in baby teeth, according to a new study.

Xylitol, approved in the United States for use in food since 1963, acts as an antibacterial agent against organisms that cause cavities. Previous studies showing its effectiveness have mainly involved chewing gum or lozenges in school-age children with permanent teeth.

In the new study, researchers tested the xylitol syrup in 94 children, 9 months to 15 months old, in the Republic of the Marshall Islands, an island chain in the Pacific Ocean where, they said, early childhood tooth decay is a major problem. Two groups of children were given 8 grams of xylitol syrup a day, in either two or three doses, and a third group was given a single 2.67-gram dose of the syrup each day.

Children in third group, which served as a control, or comparison, group, were given a small dose of the syrup because Marshall Island officials would not allow the use of a placebo.

After an average of 10.5 months, tooth decay was found in about 24 percent of the children who had gotten two doses of xylitol syrup a day, 41 percent of children who received three doses of xylitol syrup a day and in 52 percent of children in the control group.

Children in the two-dose group had, on average, 0.6 decayed teeth, compared with 1.0 in the three-dose group and 1.9 in the control group.

"Our results suggest that exposure to xylitol (8 grams per day) in a twice-daily topical oral syrup during primary tooth eruption could prevent up to 70 percent of decayed teeth," wrote Dr. Peter Milgrom of the University of Washington, Seattle, and colleagues.

"Dividing the 8 grams into three doses did not increase the effectiveness of the treatment," the researchers said. "These results provide evidence for the first time (to our knowledge) that xylitol is effective for the prevention of decay in primary teeth of toddlers."

Though they said that more research is needed, the researchers added that xylitol appears to be a cost-effective preventive measure in populations with high rates of tooth decay.

The study appears in the July issue of Archives of Pediatrics & Adolescent Medicine. The findings were also released in July 2008 at the annual meeting of the International Association for Dental Research in Toronto.

The findings are "encouraging and suggest the addition of this approach to pharmacologic management in public health and individual care settings," Dr. Burton L. Edelstein of the College of Dental Medicine at Columbia University in New York City wrote in an accompanying editorial in the journal. "Xylitol application, like fluoride varnish application, will likely become a routine element of early childhood caries [cavity] control."

"The finding, however, that early childhood caries prevalence remained at 24 percent to 41 percent among treated children at the close of the trial in a high-caries-experience population reminds us that no single 'silver bullet' is going to solve the problem of early childhood caries," Edelstein added.

SOURCE: JAMA/Archives journals, news release, July 6, 2009