The current study is a prospective randomised study-Comparison of photodisinfection with chitosan nanoparticles enriched indocyanine green over indocyanine green as an adjunct to open flap debridement in the management of stage II/III grade B/C periodontitis.

A total of 24 patients fulfilling inclusion criteria will be randomly assigned into two treatment groups (Test and Control). Open flap debridement followed by photodynamic therapy using dyes is carried out.

Test group (n=12) - PDT with Chitosan nanoparticles enriched ICG Control group(n=12) - PDT with ICG Microbial levels of P.gingivalis is analysed with PCR analysis on baseline and 3 months after intervention.

Inclusion criteria:

• Systemically healthy subjects
• Age group 30-55yrs.
• Diagnosed with Stages II/III grade B/C periodontitis.
• Presenting with persistent pocket depth ≥5mm after initial non-surgical therapy.
• Optimal plaque control
• Good compliance

Exclusion criteria:

• Subjects on antibiotic therapy within last six months of enrollment
• Previous history of periodontal surgery
• Allergy to drugs and materials used in this study
• Pregnant woman
• Subjects with deleterious habits like smoking, tobacco chewing.