The Effect of Subgingival Curcumin Gel With and Without Photodynamic Therapy as Adjunctive Periodontal Treatment in Type 2 Diabetes Mellitus Patients: A Split-Mouth Clinical and Microbiological Study.

Background: The study aimed to determine the quantity of periodontopathic and total bacteria on subgingival plaque from patients with periodontitis and uncontrolled diabetes and to compare adjunctive periodontal therapy using topical Curcuma longa extract gel with and without photodynamic treatment using blue light-emitting diodes (LEDs). Clinical periodontal parameters such as probing depth (PD), clinical attachment level (CAL), and bleeding on probing (BOP) were assessed to evaluate the efficacy of the treatments. Methods: Thirty patients with diabetes mellitus (DM), a history of poor glycemic control, and chronic periodontitis were enrolled in this clinical and microbiological split-mouth study. After conventional periodontal treatment, scaling, and root planing, the most severe sites on the premolar or molar teeth with periodontal pockets measuring ≥5 mm were selected and randomly divided into two groups: the C. longa extract gel group (with a concentration of 25 µg/g) and the photodynamic group (C. longa extract gel 25 µg/g irradiated with blue light energy density = 16.8 J/cm² for 120 s). All teeth were examined for clinical periodontal parameters data (PD, CAL, plaque index [PI], and BOP) and microbiological data (Porphyromonas gingivalis, Prevotella intermedia, Fusobacterium nucleatum, Aggregatibacter actinomycetemcomitans, and total bacteria), measured using TaqMan Multiplex real-time polymerase chain reaction, at weeks 0, 1, 2, and 12. The Mann-Whitney U test was utilized to compare clinical outcomes between groups, while the Wilcoxon Signed Rank test at a 95% confidence level was employed to analyze the amount of periodontal pathogens within the same group. Results: After the 12-week follow-up period, significant improvements were observed in all clinical parameters across both groups. However, the reduction in both CAL and BOP was significantly higher in the photodynamic group compared to the curcumin gel alone group, indicating enhanced periodontal health outcomes in the former. Microbiologically, both groups exhibited a decrease in total bacterial count and a reduction in periodontopathic bacteria. Importantly, the photodynamic group demonstrated a significant decrease in F. nucleatum and P. intermedia counts, key pathogens associated with periodontal disease progression. This suggests that photodynamic therapy (PDT), when used with curcumin gel, not only improves clinical parameters but also promotes a favorable shift in the periodontal microbial profile. Conclusion: Our findings highlight that PDT with curcumin gel as a photosensitizer (PS) is more effective than curcumin gel alone in achieving clinical attachment gain, reducing gingival inflammation, and suppressing specific periodontal pathogens. This combined therapy approach holds promise for managing periodontal disease by addressing both clinical symptoms and microbial factors.