Background: Probiotic bacteria with anti-inflammatory properties have the potential to be of therapeutic benefit in gingivitis.Objective: To evaluate the effects of potential probiotic strains on inflammatory mediators involved in early gingivitis using an ex vivo inflammation model.Methods: Strains were screened in viable and attenuated forms for effects on bacterial lipopolysaccharide (LPS)-stimulated release of interleukins (IL)-1β, -6 and -8, tumor necrosis factor-α, prostaglandin E2 and 8-isoprostane from human primary monocytes, and then, if anti-inflammatory effects were shown, on IL-1β-stimulated release of inflammatory mediators from primary gingival fibroblasts. Lead strains were evaluated for optimal dosing, batch-to-batch variation and functional consistency in toothpaste.Results: Twenty-one of 73 strains showed anti-inflammatory effects in monocytes; of which, seven showed effects in both viable and attenuated forms. Seven of 14 strains showed effects in fibroblasts. Strains Lactobacillus paracasei LPc-G110(SYBIO-15) and Lactobacillus plantarum GOS42(SYBIO-41) induced statistically significant dose-dependent reductions in the release of multiple inflammatory mediators from monocytes, which were consistent across batches. Viable L. paracasei LPc-G110 tooth paste significantly reduced IL-6, IL-8 and prostaglandin E2 release from monocytes versus placebo.Conclusion: Strains L. paracasei LPc-G110 and L. plantarum GOS42 have potential for use as probiotics in oral care products to reduce gingival inflammation.