The Effectiveness of Chelating Solutions and Photodynamic Therapy in Inactivating Bacterial Lipopolysaccharides During Endodontic Therapy.

Objective: The purpose of this study was to evaluate the influence effects of different endodontic treatments ���, such as chelation ng solutions and antimicrobial photodynamic therapy (aPDT), on the rreductionng the amount of endotoxin levels in root canals.

Methods: Eighty human single-rooted teeth had their crowns sectioned, and the root canals were prepared. All samples and materials were sterilized using Cobalt-60 irradiation. Subsequently, 10 ��L of fresh lipopolysaccharide (LPS) was inoculated into the root canals and incubated for 3 days. On the fourth day, experimental treatments were applied to the root canals according to the groups (n=10): [1] pyrogen-free water, [2] 0.005% methylene blue, [3] diode LASER, and [4] 0.005% methylene blue + diode LASER (PDT), [5] 2.5% sodium hypochlorite, [6] 17% trisodium ethylenediaminetetraacetic acid (EDTA), [7] 10% tetrasodium EDTA, [8] 18% etidronate (HEBP). The exposure time for each solution and light irradiation was 5 minutes. The samples collected after treatment were analyzed using the Limulus Amebocyte Lysate test to quantify endotoxins. The data obtained were subjected to Kruskal-Wallis analysis followed by Dunn's test.

Results: All treatments demonstrated efficacy in reducing endotoxin levels in root canals compared to the use of pyrogen-free water (control). A statistically significant reduction was observed in the groups treated with 17% EDTA and 18% HEBP compared to the control group.

Conclusion: Short-term application (5 minutes) of 17% EDTA and 18% HEBP chelating solutions significantly reduced LPS in root canals and may be effective adjuncts in endodontic therapy. (EEJ-2025-03-032).