Effect of Beverages/Teas Containing Plant-Derived Polyphenols on Children's Supragingival Plaque Bacteria

Objectives: We have demonstrated that many plant-derived polyphenols from cranberry, tea (Camillia sinensis) and grape products inhibited growth or virulence factors of oral pathogens. We hypothesize that teas/beverages rich in antimicrobial polyphenols suppress human dental plaque bacteria and may benefit oral health. The objective of this study was to investigate the effect of selected commercially marketed ready-to-drink teas and beverages containing berry extracts on in vitro growth and biofilm formation of supragingival plaque isolated from children.
Methods: Supragingival plaque bacteria collected from buccal and lingual tooth surfaces of sixteen 7-14 years old children were used. Plaque bacterial suspension was incubated anaerobically at 37C in 96-well microtiter plates containing serially diluted test teas/beverages in a chemically defined medium. Growth was monitored spectrophotometrically (550nm) for 24 hr at 37C and biofilm formation was determined using crystal violet stain after 48hr. The test agents included black and green teas with or without cinnamon or raspberry flavor; cranberry juice cocktails; and ready-to-drink unflavored and raspberry flavored teas.
Results: Test teas prepared from tea bags inhibited growth (0.8-6 mg leaves/ml) and biofilm formation of plaque bacteria (0.8-1.6 mg leaves/ml). Ready-to-drink unsweetened tea and raspberry tea modestly inhibited growth at 1:1 dilution (55-75%), however, > 90% inhibition on biofilm formation was noted. Beverages containing cranberry juice suppressed growth and biofilm formation of plaque bacteria at 1:1 dilution. Compared to the control, biofilms formed in the presence of test teas/beverages were loosely adherent and was easily dislodged from surfaces.
Conclusions: Beverages/Teas containing antimicrobial plant-derived polyphenols may benefit children’s oral health by suppressing growth and biofilm formation of the supragingival plaque bacteria. These beverages may be preferred over other commonly consumed sugary beverages. The concept of oral diseases prevention using natural foods or beverages in the diet may be a novel, practical, and acceptable approach to promote oral health in children.