Published online Mar 20, 2026. doi: 10.5493/wjem.v16.i1.117125
Revised: December 22, 2025
Accepted: February 3, 2026
Published online: March 20, 2026
Processing time: 106 Days and 17.1 Hours
Periodontitis is a chronic inflammatory disease triggered by a polymicrobial challenge to the periodontium. While scaling and root planing (SRP) is the gold standard for treatment, its efficacy is often limited by incomplete pathogen eradication and rising antimicrobial resistance. Antimicrobial photodynamic therapy (aPDT) has emerged as a potent adjunctive treatment, utilizing light-activated photosensitizers to induce targeted bacterial lysis. Specifically, the delivery of indocyanine green (ICG) via chitosan nanoparticles (CNPs) may enhance stability and penetration, offering a synergistic approach to improving clinical outcomes when combined with SRP.
To evaluate the overall improvements in various clinical and microbiological periodontal parameters in periodontitis patients undergoing aPDT with CNPs-ICG.
Thirty periodontitis patients having interdental clinical attachment loss (CAL) ‘detectable’ at ≥ 2 non-adjacent teeth, buccal or oral CAL ≥ 3 mm with pocketing > 3 mm detectable at ≥ 2 teeth were randomly assigned to aPDT with CNPs-ICG + SRP (test) group and conventional SRP + laser irradiation only (control) group in a split-mouth design. At baseline, 1-month and 3-months plaque index (PI), modified sulcular bleeding index, pocket probing depth (PPD) and relative clinical attachment level (RCAL) and microbiological tests were recorded.
The test group showed more improvement in PPD (7 mm to 3.26 mm in 1-month and 3.13 mm in 3-months) and RCAL (12 mm to 8.26 mm in 1 month and 8.4 mm in 3 months) than control group that showed PPD reduction from 6.7 mm (at baseline) to 3.73 mm at 1-month and 3.76 mm at 3 months and RCAL reduction from 12.23 mm (at baseline) to 8.7 mm at 1-month and 8.9 mm at 3-months with a statistically significant difference (P = 0.001). The test sites showed a statistically significant (P = 0.001) increase in negative microbiological test results (from 10% at baseline to 80% at 1 month and 3 months follow-up) compared to control sites (6.7% at both baseline and 1-month and 3-months follow-up).
aPDT using CNPs-ICG + SRP can be considered as a better procedure in improving periodontal clinical parameters like PPD and RCAL and in reducing periodontal pathogens than conventional SRP alone.
Core Tip: This trial assesses the adjunctive use of indocyanine green-doped chitosan nanoparticles (CNPs-ICG) in antimicrobial photodynamic therapy (aPDT) with scaling and root planing (SRP) for periodontitis management. Conducted at SCB Dental College and Hospital, Cuttack, on 30 patients, the trial demonstrated significantly superior clinical and microbiological outcomes-particularly in improvement in probing depth, gain in clinical attachment level, and bacterial elimination-in comparison to conventional SRP alone. CNPs-ICG enhanced biofilm targeting and treatment precision through improved photosensitizer delivery. The findings highlight aPDT with CNPs-ICG as an effective, non-surgical, and minimally invasive alternative for patients unsuitable for periodontal surgery.