BACKGROUND AND AIM: Periodontal disease is a chronic microbial infection characterized by inflammation and destruction of periodontal tissues. Probiotics, such as MATERIAL AND METHODS: A single-center, double-blind, placebo-controlled, parallel-arm, randomized clinical trial was conducted with 30 patients aged 30-60 years diagnosed with chronic periodontitis were randomized into test (SRP + probiotic fiber) and control (SRP + placebo fiber) groups. Clinical parameters, including plaque index (PI), bleeding index (BI), probing pocket depth (PPD), clinical attachment level (CAL), and microbial load ( RESULTS: Both groups showed significant improvements in clinical parameters (p<
0.05). The test group achieved a 45.66% reduction in PI, 57.83% reduction in BI, and significant improvements in PPD (43.06%) and CAL (43.06%). Microbial load decreased more in the test group (63.00%) than in the control group (26.08%). CONCLUSIONS: Adjunctive use of