Reduction of gingival inflammation after 3 sessions of antimicrobial photodynamic therapy in generalized periodontitis non-surgical treatment: a randomized controlled clinical trial

Purpose The aim of this randomized controlled study was to investigate changes in periodontal clinical parameters of individuals with generalized periodontitis with association of scaling and root planing (SRP) and multiple sessions of antimicrobial photodynamic therapy (aPDT). Methods With a split-mouth model, patients received SRP alone in control side and SRP and three sessions of aPDT in all teeth of the test side with 0.01% methylene blue solution (Formula & Action, São Paulo, Brazil) and 5 min of pre-irradiation time. The irradiation was carried out with red laser source with Indium Gallium Aluminum Phosphide, with wavelength of 660 nm, output power of 100 mW, output energy of 9 J, fluence of 300 J/cm 2 , 90 s time, output spot of 3 mm 2 , irradiance of 3.33 W/cm 2 (Laser Duo, MMOptics, São Paulo, Brazil), and in contact with the gum (mesiobuccal, distobuccal, mesiolingual, distolingual sites), in continuous wave mode. Clinical parameters measured at six sites per tooth (mesiobuccal, buccal, distobuccal, mesiolingual, lingual, distolingual) at baseline, 45 and 90 days after intervention, were probing depth (PD), clinical attachment level (CAL), plaque index (PI), and bleeding on probing (BOP). Results Twenty-four individuals with mean age of 52 years (± 12.7), 11 men and 13 women, were treated; 1626 sites received SRP and 1668 sites SRP and aPDT. PI reduced significantly in both groups. BOP had a higher reduction in the aPDT group ( P > 0.001). Levels of PD and CAL in both sides improved, with no statistical difference between therapies. Conclusion Although 3 sessions of aPDT associated with SRP provided no additional effect on PD and CAL levels after periodontal treatment, it showed a beneficial effect in gingival inflammation in a 3-month follow-up, which maybe can be attributed to several applications of aPDT after mechanical treatment of periodontitis.