Subgingival Lactobacillus Reuteri as an Adjunct to Non-Surgical Periodontal Therapy in Diabetic Patients (LREUTERI-DM)

Periodontitis is a chronic inflammatory disease associated with dysbiotic subgingival biofilms and is strongly influenced by diabetes mellitus. Chronic hyperglycemia may impair immune function and wound healing, resulting in increased periodontal destruction and poorer treatment outcomes. Non-surgical periodontal therapy based on scaling and root planing (SRP) remains the standard treatment; however, residual periodontal pockets may persist after therapy.

Lactobacillus reuteri probiotics have demonstrated antimicrobial, anti-inflammatory, and host-modulatory properties and may enhance periodontal healing. This randomized controlled clinical trial evaluated the adjunctive effects of subgingival administration of a liquid probiotic preparation containing Lactobacillus reuteri in diabetic patients with Stage III Grade B or higher periodontitis.

Forty periodontal sites were randomly allocated to either a test group receiving SRP plus subgingival Lactobacillus reuteri probiotics or a control group receiving SRP plus saline irrigation. A second application was performed at the 1-month visit. Clinical outcomes included plaque index, gingival index, bleeding on probing, probing pocket depth, and clinical attachment level. Glycemic control was evaluated using HbA1c levels, and microbiological analysis was performed using real-time PCR for Porphyromonas gingivalis, Tannerella forsythia, and Fusobacterium nucleatum.

Assessments were conducted at baseline, 1 month, and 3 months. The primary objective was to evaluate changes in clinical outcomes. Secondary objectives included microbiological and glycemic outcomes.