Effectiveness of Natural Photosensitizers in Antimicrobial Photodynamic Therapy Within Dentistry: A Systematic Review of RCTs.

Background

Antimicrobial photodynamic therapy (aPDT) is a useful adjunct for managing oral biofilm diseases. Natural photosensitizers may be safer and more biocompatible than synthetic ones, but their dental effectiveness is still unclear.

Methods

A PRISMA compliant review (PROSPERO ID: CRD420251233910) searched PubMed, Embase, Scopus, and the Cochrane Library for randomized controlled trials published from 2015 to 2025 that used natural photosensitizers for aPDT in dental settings. Three reviewers screened studies, extracted data, and assessed bias with a nine-domain tool adapted for photodynamic therapy.

Results

Eleven of 249 records met the established criteria. Natural photosensitizers included curcumin, riboflavin, phycocyanin, chlorophyll derivatives, and plant extracts, tested in periodontitis, peri-implant mucositis, denture stomatitis, caries-related biofilms, and general oral decontamination. Most trials showed short-term microbial reductions and modest clinical gains, with performance comparable to chlorhexidine, methylene blue, or standard care. Adverse effects were minimal. Study quality was generally good, but wide variation in photosensitizer type, light settings, and outcomes, and short follow-up periods hindered meta-analysis and limited conclusions about long-term effectiveness.

Conclusions

Natural photosensitizer-based aPDT appears effective and safe as an adjunct, offering consistent short-term microbiological improvements. Current evidence does not support replacing established antimicrobial approaches. Larger, well-controlled trials with standardized methods and longer follow-up periods are needed to define best practice and clarify the role of aPDT in routine dentistry.