Lactobacillus species (often in mixed probiotic formulations) have been studied for their potential benefits in supporting oral health, including the management of gingivitis. Several randomized controlled trials and systematic reviews suggest that certain strains of Lactobacillus, such as L. reuteri, L. rhamnosus, and L. salivarius, may help reduce gingival inflammation and bleeding when administered as lozenges, tablets, or mouth rinses alongside standard oral hygiene practices. The proposed mechanisms include modulation of the oral microbiota, inhibition of periodontal pathogens, and immune modulation, which collectively may reduce the severity of gingivitis.

However, while there is a growing body of evidence, the overall quality and consistency of clinical data are moderate. Some studies report statistically significant reductions in gingivitis indices and bleeding scores, while others show minimal or no effect. Meta-analyses generally conclude that probiotics containing Lactobacillus can provide a modest but measurable benefit as an adjunct to mechanical plaque control. There is currently insufficient evidence to support their use as a standalone therapy.

In summary, the use of mixed Lactobacillus probiotics for gingivitis is supported by scientific research, though the strength of evidence is moderate (3/5), and more large-scale, high-quality studies are needed to establish standardized protocols and identify the most effective strains and dosages.