Antimicrobial photodynamic therapy (aPDT) is associated with photosensitizing agents which promote the generation of free radicals and singlet oxygen, which are cytotoxic to certain bacteria. Leukocyte and platelet-rich fibrin (L-PRF) has been used extensively in the treatment of intrabony defects and achieved excellent results. It acts as an immune regulation node with inflammation control abilities, including a slow continuous release of growth factors which stimulates periodontal regeneration. The aim of this study is to evaluate the adjunctive effects of aPDT with and without L-PRF in aggressive periodontitis patients.