The Impacts of Synbiotic Supplementation on Periodontal Indices and Biomarkers of Oxidative Stress in Type 2 Diabetes Mellitus Patients with Chronic Periodontitis Under Non-Surgical Periodontal Therapy. A Double-Blind, Placebo-Controlled Trial

Double-blind, placebo-controlled trial in adults with type 2 diabetes mellitus and chronic periodontitis receiving non-surgical periodontal therapy. For the synbiotic intervention arm, 23 participants were randomized; their mean age was 48.6 ± 5.8 years, 17 were female and 6 were male, and mean BMI was 24 ± 3.6 kg/m^2. Participants were followed for 8 weeks with periodontal, inflammatory, oxidative stress, dietary, and physical activity assessments.

Adults in the active arm received 1 oral capsule daily of a multispecies synbiotic supplement (500 mg) for 8 weeks. Each capsule contained seven viable strains plus 100 mg fructooligosaccharide: Lactobacillus acidophilus UBLA-34, L. casei, L. rhamnosus, L. bulgaricus, Bifidobacterium breve, B. longum, and Streptococcus thermophilus. The control group received a matching placebo capsule without bacteria or fructooligosaccharide; all participants also underwent non-surgical periodontal therapy.

Synbiotic supplementation alongside periodontal therapy was associated with clinically and biologically favorable changes in periodontal status and oxidative stress markers. In the intervention arm, probing depth decreased from 4.30 ± 0.76 mm to 3.47 ± 0.79 mm (p<0.001), clinical attachment level decreased from 3.26 ± 0.61 mm to 2.73 ± 0.75 mm (p=0.002), IL-1β decreased from 2.64 ± 0.41 to 2.19 ± 0.48 pg/mL (p<0.001), and MDA decreased from 18.25 ± 1.89 to 17.22 ± 1.82 µM (p<0.001). Antioxidant markers also improved, including TAC from 0.588 ± 0.08 to 0.636 ± 0.09, SOD from 14.32 ± 2.52 to 16.08 ± 4.02, and GPx from 215.77 ± 62.57 to 230.5 ± 57.93. The authors concluded that synbiotic supplementation may improve inflammatory, antioxidant, and periodontal status beyond non-surgical periodontal therapy alone; no serious supplement-related adverse events were reported.

The active-arm sample was small (N=23), limiting precision and generalizability. The trial was short in duration (8 weeks) and appears to be a single-center study, so longer-term durability and broader applicability are uncertain. The source packet provides mainly short-term biomarker and periodontal outcomes, with limited detail on between-group effect sizes in the extracted arm-level data.