There is a weak evidence to support the usage of probiotics in lowering inflammatory periodontal parameters in gingivitis. 

A meta-analysis and systematic review were carried out to investigate efficacy of the probiotics to manage patients having gingivitis.

Databases like CENTRAL, EMBASE, and MEDLINE were extensively searched up to May 2019. The randomized and/or controlled clinical trials were taken into consideration. The studies incorporating ≥10 subjects per group diagnosed with gingivitis were chosen that comparatively evaluated efficacy of probiotics in any form vs. placebo.

In total, 10 double-blind placebo-parallel randomized controlled trials  were incorporated. Gingival index and bleeding on probing was the major endpoint while plaque index was the secondary endpoint. The forest plots were developed reporting weighted mean difference of outcomes along with 95% confidence intervals (CI).

At the follow-up, the probiotic administration was found to be effective to treat gingivitis. In patients receiving probiotics, the mean percentage of bleeding on probing ranged from 11.87% to 21.7%, and in patients receiving placebo, it ranged from 15% to 33%. Taking into consideration the impact of Lactobacillus reuteri, the overall mean difference for gingival index (WMD = -0.48) and plaque index (WMD = 0.18) did not display any vital significance between both the cohorts.

Probiotics may not be beneficial to treat inflammatory periodontal parameters in patients suffering from gingivitis.