Related Experiment Video
Updated: May 30, 2026
LED-Based In Vitro Screening for Assessing Photoactivable Molecules in Bacterial Photodynamic Inactivation
Published on: January 24, 2025
Evaluation of photodynamic therapy using a light-emitting diode lamp against Enterococcus faecalis in extracted human
Alejandro Rios1, Jianing He, Gerald N Glickman
1Department of Endodontics, Baylor College of Dentistry, The Texas A&M University System Health Science Center, Dallas, Texas 75246, USA.
Introduction:
Photodynamic therapy (PDT) with high-power lasers as the light source has been proven to be effective in disinfecting root canals. The aim of this study was to evaluate the antimicrobial effect of PDT using toluidine blue O (TBO) and a low-energy light-emitting diode (LED) lamp after the conventional disinfection protocol of 6% NaOCl.
Methods:
Single-rooted extracted teeth were cleaned, shaped, and sealed at the apex before incubation with Enterococcus faecalis for 2 weeks. Roots were randomly assigned to five experimental groups and three control groups. Dentin shavings were collected from the root canals of all groups with a #50/.06 rotary file, colony-forming units were determined, and the bacterial survival rate was calculated for each treatment.
Results:
The bacterial survival rate of the NaOCl/TBO/light group (0.1%) was significantly lower (P < .005) than the NaOCl (0.66%) and TBO/light groups (2.9%).
Conclusions:
PDT using TBO and a LED lamp has the potential to be used as an adjunctive antimicrobial procedure in conventional endodontic therapy.
