Laser Treatment With Methylene Blue vs. Nanoparticle-Assisted Photodynamic Therapy for Gingival Pigmentation: A Randomized Clinical Trial

This prospective, randomized, controlled, single-blinded, three-arm clinical trial compared the clinical effectiveness of conventional methylene blue-mediated photodynamic therapy (MB-PDT) and methylene blue nanoparticle-mediated photodynamic therapy (MB-NP-PDT) as adjuncts to diode-laser treatment of physiological gingival pigmentation. A total of 45 systemically healthy participants with physiological gingival pigmentation were randomly allocated in a 1:1:1 ratio to three groups: diode-laser gingival depigmentation alone, conventional 0.1% methylene blue PDT followed by diode-laser depigmentation, or 0.1% methylene blue nanoparticle PDT followed by diode-laser depigmentation. Participants were followed for 6 months. The study assessed gingival pigmentation reduction, complete pigmentation clearance, recurrence, objective gingival color changes, epithelialization and healing time, postoperative pain, patient satisfaction, and treatment-related adverse events.