Chewing sticks -- used for oral hygiene for thousands of years in the Middle East, Africa and Asia -- clean teeth and prevent plaque as effectively as toothbrushes. Scientists have now isolated and identified the antimicrobial agents in these sticks that kill oral pathogens and help prevent diseases.
The new research is reported in the March 3 Web edition of the Journal of Agricultural and Food Chemistry by researchers from the University of Illinois at Chicago (UIC) and the University of Stellenbosch in Tygerberg, South Africa. The peer-reviewed journal is published by the American Chemical Society, the world's largest scientific society. The report is scheduled to appear March 20 in the journal's print edition.
Chewing sticks, pencil-sized sticks made from the root or stem of local trees and shrubs, are chewed on the end until they become frayed into a brush. People then clean their teeth with these frayed sticks - simultaneously removing plaque and massaging their gums.
"While tooth-brushing with toothpaste is arguably the most common method of oral hygiene in developed nations, a large portion of the world's population does not use toothbrushes," says Christine Wu, Ph.D., an associate professor of periodontics in the College of Dentistry at UIC and a co-author of the study. In many countries, including India, Jordan, Saudi Arabia, and others in the Middle East, Asia and Africa, chewing sticks are important tools for oral healthcare.
Wu and her colleagues investigated chewing sticks used in Namibia -- twigs from the plant Diospyros lycioides, commonly known as "muthala." The scientists isolated six chemical compounds that demonstrated antimicrobial activity. These compounds may help kill the oral pathogens responsible for periodontal disease.
A 1993 oral health survey showed that although only about 20 percent of Namibians use chewing sticks, those who used the sticks had fewer cavities. The World Health Organization has recently recommended and encouraged the use of chewing sticks as an effective tool for oral hygiene.
"Regular use of this alternative oral hygiene tool may help reduce the incidence of caries [cavities] and gum inflammation in rural populations where professional care is less available and toothbrushes are less affordable," says Wu.
Wu is now working on a collaborative study in Sudan to compare the oral health of chewing-stick users with non-users. She also plans to investigate other types of chewing sticks for their antimicrobial properties. Her work is funded by the National Institute for Dental and Craniofacial Research, part of the National Institutes of Health, and private industries.
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Journal of Agricultural and Food Chemistry