Clinical and microbiological effects of the adjunctive use of probiotics in the treatment of gingivitis: A randomized controlled clinical trial

Aim To evaluate the efficacy of a probiotic combination in the treatment of gingivitis and to assess its impact on the subgingival microbiota. Materials and Methods A placebo‐controlled clinical trial was conducted in gingivitis subjects during 6 weeks. Test treatment consisted of the administration of two oral tablets per day containing the probiotic strains Lactobacillus plantarum , Lactobacillus brevis and Pediococcus acidilactici ; the control group received the same tablets but without live bacteria. The main outcome variable was the changes in gingival index ( GI ). Subgingival samples were collected and analysed by quantitative polymerase chain reaction ( qPCR ) for five putative periodontal pathogens. Outcome variables were compared between and within groups, and multiple regression analysis was performed. Results A total of 59 patients (29 tests, 30 placebos) were included in the analysis. Both treatment groups experienced a statistically significant improvement in mean GI ( p  < .0001), but no differences between treatment groups were found for any clinical index. A significantly higher reduction in the number of sites with higher GI scores ( GI  = 3 at baseline) was observed in the test group. In subgingival samples, a significant reduction in T. forsythia was significant only in the test group ( p  < .008). Conclusions The use of probiotic tablets containing L. plantarum , L. brevis and P .  acidilactic i did not lead to significant changes in mean GI ; although a significant reduction occurred in the number of sites with severe inflammation. Furthermore, the adjunctive use of this probiotic promoted a significant microbiological impact.