The effects of green tea polyphenols, inhibitors of various biological activities of cariogenic bacteria in vitro, on caries development were examined using conventional rats. A total of 96 male rats were divided into 8 groups and the rats in the test groups were given tea polyphenols ranging from 0.1% to 0.5% in their cariogenic diet or drinking water for 40 days. Total fissure caries lesions was significantly reduced by the addition of tea polyphenols to the diet or in the drinking water. Diet containing 0.1% tea polyphenols demonstrated about 40% reduction of total fissure caries lesions. No toxic effect of tea polyphenols on rats were observed under these experimental conditions.

Abstract:A cup of tea (containing about 0.49 mg F) containing soluble fluoride in the optimum necessary amount was recommended after every school lunch to 298 school children of Suhara in Sumon, Niigata prefecture, for about 250 days from December, 1975 to November, 1976. Increment lesions which appeared at three carious predirective sites, i. e., pits and fissures, proximal, and free gingival smooth surfaces of the children of the test school in the Suhara district were compared to the lesions found at the same sites in 185 children of three control schools in the Kamijo district of the same village. Reduction rates at each site were 52.8% for the pit and fissures and 57.2 % for the proximal sites, but there was no reduction at the free gingival sites.The main routes of natural fluoride taken in our body were simplified by Arif1) into four foodstuffs: water and salt from minerals, tea from vegetables, and fish from the animal kingdom.

In the course of developing a synthetic peptide vaccine for dental caries, we identified a unique 13-mer peptide named PAc(365-377), TYEAALKQYEADL, as a minimum peptide inducing cross-inhibiting antibodies to a cell surface protein antigen (PAc) of Streptococcus mutans. However, the peptide could hardly induce the production of antibody in the absence of adjuvant. Thus using this peptide as a unit peptide, tandem constructs of dimeric unit peptide with or without spacer amino acid residues were synthesized, and their antigenicities were examined in B10.D2 mice. Significant augmentation of antigenicity was obtained in all of the dimeric unit peptides with spacers, especially for lysine spacers. In addition, analysis for cross-reactivity of anti-construct antibodies against a set of double valine-substituted analogues of the unit peptide revealed that the di-lysine spacer might be more effective in inducing the cross-reacting antibodies to rPAc.

A cell surface protein antigen (PAc) of Streptococcus mutans may be involved in the binding of bacteria to the tooth surface, and has long been focused upon as a candidate for a preventive vaccine of dental caries. Previously the peptide PAc (365-377) was shown to raise an antibody in B10.D2 mice which inhibited the binding of salivary components to the PAc molecule. Using this peptide as a unit peptide, two constructs based on multiple antigenic peptides, and several types of tandem repeats of two or three copies were synthesized to estimate the immunogenicity of these peptides. Increase in the immunogenicity was observed for all constructs with the use of an adjuvant compared to the unit peptide alone. However, the tandem repeat constructs generally induced antibody production in the absence of adjuvant, while the multiple antigenic peptide constructs did not induce antibody production under the same condition. Although such a phenomenon may be restricted to this particular peptide sequence, these results may influence the strategy for the design of peptide vaccines.