Effects of orally administered Lactobacillus salivarius WB21 supplement on periodontal clinical parameters and microflora

The aim of this study was to evaluate whether the oral administration of lactobacilli could change the periodontal condition and microflora compared with placebo. Sixty-six healthy volunteers were randomized into two groups to receive lactobacilli or placebo for 8 weeks. The mean Plaque Index, Gingival Index, and bleeding on probing were significantly improved at 4 and 8 weeks in both groups, but showed the biggest change on smokers in the test group. Occurrence of Porphyromonas gingivalis and Treponema denticola in the subgingival plaque sample significantly decreased in the test group at 8 weeks. Oral administration of probiotic lactobacilli successfully reduced the prevalence of periodontopathic bacteria from the subgingival plaque, and possibly contributed to the beneficial effects on periodontal conditions.