Objective: Probiotic bacteria are thought to reduce the risk of some infectious diseases. The aim of the present study was to examine whether or not short-term consumption of ice-cream containing bifidobacteria can affect the salivary levels of mutans streptococci and lactobacilli in young adults.
Material and methods: A double-blind, randomized crossover study was performed and 24 healthy subjects (mean age 20 years) were followed over 4 periods. During periods 2 and 4 (10 days each), they ingested 100 ml (53 g) ice-cream containing Bifidobacterium lactis Bb-12 once daily or a control ice-cream without viable bacteria. Periods 1 and 3 were run-in and washout periods, respectively. Salivary mutans streptococci and lactobacilli were enumerated with chair-side kits at baseline and immediately after the intervention period.
Results: A statistically significant reduction (p<0.05) of salivary mutans streptococci was recorded after consumption of the probiotic ice-cream. A decline of high mutans streptococci counts was also seen after intake of the control ice-cream, but the difference compared to baseline was not statistically significant. The salivary lactobacilli levels were unaltered after both regimes.
Conclusions: Daily consumtion of ice-cream containing probiotic bifidobacteria may reduce the salivary levels of mutans streptococci in young adults.