Studio dei benefici per la salute orale di Levilactobacillus brevis CD2: Un approccio traslazionale

Background and Aim: Emerging in vitro and in vivo evidence supports the application of probiotics as a natural approach to promoting oral and systemic health. This double-blind, randomized, placebo-controlled trial investigated the efficacy of Levilactobacillus brevis CD2 (CNCM I-5566), a multifunctional probiotic widely adopted in oral medicine, in preserving and enhancing key oral health parameters. Methods: Thirty healthy adult volunteers were randomly assigned to receive four lozenges per day containing either L. brevis CD2 (n = 15) or a placebo (n = 15) for a duration of four weeks. Clinical assessments included full-mouth bleeding on probing (BoP) and plaque index (PI). Unstimulated saliva samples were collected to evaluate salivation rate, pH, and buffering capacity. Salivary biomarkers analysed included glucose, D-lactate, secretory immunoglobulin A (sIgA), and nitrate and nitrite levels, serving as indicators of oral nitrate-reducing capacity. The ex vivo nitrate-reducing potential of the probiotic lysate was also evaluated, along with its effects on pH, buffering capacity, and D-lactate levels after 3 hours of incubation. The impact of L. brevis on α-amylase (salivary and pancreatic) activity was also assessed. Measurements were taken at baseline, post-intervention (week 4), and two weeks after washout. Results: After 4 weeks of supplementation, the probiotic group showed significant improvements in BoP and PI compared with baseline and placebo. Salivation rate increased significantly at both post-treatment and washout timepoints. While pH remained stable, buffering capacity improved following probiotic intake. Salivary glucose and D-lactate levels decreased, whereas sIgA levels increased and remained elevated after washout. A notable enhancement in oral nitrate-reducing capacity was observed in the probiotic group. Additionally, L. brevis CD2 effectively inhibited salivary and pancreatic α-amylase activity. No adverse events were reported. Conclusions: L. brevis CD2 supplementation significantly improves both clinical and biochemical markers of oral health, including inflammation, plaque accumulation, salivary flow, immune response, and nitrate-reducing capacity. Its ability to modulate α-amylase activity further suggests potential systemic benefits. These results support the use of L. brevis CD2 as a safe and effective probiotic intervention for promoting oral and systemic health in healthy individuals.