Abstract
Mutans streptococci including Streptococcus mutans and Streptococcus sobrinus are aetiologically associated with the development of dental caries in humans and experimental animals. These organisms produce glucosyltransferases (GTases), which catalyse the synthesis of adherent glucan from sucrose, promoting the adherence of the organisms to the tooth surface. In addition, they release large quantities of acids from various dietary sugars. These are the essential virulence factors of mutans streptococci. We found that structural isomers of sucrose such as palatinose and trehalulose were not utilised by the organisms and no significant glucans or acids were produced. Another interesting sucrose substitute would be sugar alcohol; maltitol and palatinit are good examples. Other unique compounds developed recently are oligosaccharides rich in isomaltose and panose, which contain α (1→6) glucosidic linkage. They strongly inhibit glucan synthesis from sucrose by GTases, and cannot be degraded by most oral streptococci. These sucrose substitutes are now manufactured on an industrial scale. Enzymatic inhibition of GTases is an alternative measure to suppress caries development. Polymeric polyphenol compounds from oolong tea and hen egg yolk IgG specific for cell-associated GTase of mutans streptococci have been shown to exhibit marked GTase inhibition and decrease in caries development in rats.