Bifidobacterium lactis Bb12 Administration and Oral Microbiota in Children

Methods: In this double-blind, placebo-controlled study, infants (n=163) were assigned randomly to receive probiotic bacteria (Bb12-group), xylitol (X-group) or sorbitol (S-group). Test tablets were administered twice a day (from the age of 1-2 months) with a novel slow-release pacifier (daily dose of Bb12 10 billion CFU, xylitol 200mg). At the age of 8 months and 2 years oral samples were collected (from mucosa/plaque from teeth) for Bb12 determination (PCR) and plate culturing of mutans streptococci (ms; MSB, TYCSB), lactobacilli (Rogosa) and total facultatives (blood agar). The mothers were screened for ms (Dentocult SM Strip Mutans) in the beginning of the study.

Results: Mean duration of tablet delivery was 15.0±6.7 months. Bb12 was not detected in the oral samples. In all groups >90% of the mothers showed high salivary ms counts (≥ log 5 CFU), however, the colonization percentages of the children were lower than expected. The highest colonization percentage at the age of 2 years was found in the X-group (X-group:31%; S-group:10%; Bb12-group:6%; p<0.05). The levels of lactobacilli or total facultatives did not differ between the groups. The baseline characteristics of the three groups were similar. No differences were detected between the children with regard to number of teeth, visible plaque, use of slow-release pacifier, dietary patterns or use of antibiotics. Conclusion: Delivery B. lactis Bb12 did not affect the composition of the oral microbiota in children.

The study was supported by Emil Aaltonen and Päivikki and Sakari Sohlberg Foundations, The Finnish Dental Society and Finnish Dental Association.