Clinical Effects of Oral Probiotics on Plaque Accumulation and Gingival Inflammation in Young Adults

Abstract

Background/Objectives: Oral dysbiosis is recognized as a major contributing factor to the development of biofilm-associated oral diseases, including dental caries and gingivitis. Probiotics have emerged as promising adjunctive agents capable of modulating the oral microbiota and supporting oral health. The aim of this study was to evaluate the effects of a chewable multi-strain probiotic formulation on salivary pH, plaque accumulation, and gingival inflammation in healthy young adults.  Methods: Thirty participants aged 18–25 years were allocated to a probiotic group (n = 15) or a control group (n = 15) and monitored for 28 days. The probiotic group received chewable tablets containing *Streptococcus salivarius*, *Lactobacillus acidophilus*, *Lactobacillus plantarum*, *Lactobacillus reuteri*, and *Lactobacillus paracasei* for 14 days, followed by a 14-day washout period. Salivary pH, Plaque Index (PI), and Gingival Index (GI) were assessed at baseline, Day 14, and Day 28. Results: No significant differences in salivary pH were observed between groups throughout the study period (p > 0.05). In contrast, probiotic supplementation resulted in significantly lower PI values at Day 14 (p = 0.042) and significantly lower GI values at Day 14 (p = 0.020) and Day 28 (p = 0.033) compared with the control group. Within-group analyses also demonstrated significant reductions in plaque accumulation and gingival inflammation following probiotic administration.  Conclusion: Short-term supplementation with a multi-strain probiotic formulation improved plaque control and gingival health without significantly affecting salivary pH, supporting the potential role of probiotics as adjunctive tools in preventive oral healthcare.