Photodynamic therapy (PDT) is an innovative technique that utilizes light-activated agents, known as photosensitizers, to produce reactive oxygen species capable of targeting and eliminating pathogens. This therapeutic approach has been explored in a variety of medical fields due to its versatility and minimal invasiveness. In the context of periodontal diseases, PDT has emerged as a promising adjunctive treatment in the non-surgical management of periodontitis. Periodontitis, a chronic inflammatory disease caused by the accumulation of pathogenic bacteria in the subgingival environment, is often treated with mechanical debridement, including scaling and root planing (SRP). However, these conventional methods may not always achieve complete bacterial eradication. PDT, when used in conjunction with SRP, has the potential to significantly enhance bacterial elimination. The use of photosensitizers, activated by specific wavelengths of light, leads to the generation of singlet oxygen, which can effectively kill a broad spectrum of periodontal pathogens, including those resistant to antibiotics. As an adjunctive therapy, PDT can improve the clinical outcomes of non-surgical periodontitis treatment by reducing bacterial load, promoting tissue healing, and potentially decreasing the need for more invasive procedures. The ability of PDT to target bacteria without harming surrounding tissues makes it an attractive option for patients who require a non-invasive treatment approach. In conclusion, photodynamic therapy is a valuable addition to periodontal treatment regimens, offering enhanced bacterial reduction and improved therapeutic outcomes in the management of periodontitis.

Inclusion Criteria:

• Patients aged 18 years or older with periodontitis diagnosed according to EFP/APA 2018 criteria and with at least 10 teeth in the mouth.

Exclusion Criteria:

• Periodontal treatment in the previous six months; use of antibiotics, NSAIDs or immunosuppressants in the previous six months; acute oral infection; pregnant or breastfeeding women; teeth with grade III mobility; pockets with PD > 10 mm; use of antimicrobial mouthwash in the previous two months; patients with diabetes mellitus.