Toluidine Blue-Based Photodynamic Therapy for Antibacterial Activity and Postoperative Pain

NCT07266233 | Active Not Recruiting

• 1 other identifier: AU-DHF-ASE-01
• Study Type: interventional
• Target: 50
• Locations: 1 country
• Sites: 1

Brief Summary

This clinical study aims to evaluate the antimicrobial effectiveness and postoperative pain outcomes of photodynamic therapy using Toluidine Blue O as an adjunct to conventional root canal treatment in patients diagnosed with symptomatic irreversible pulpitis. Photodynamic therapy is a non-invasive light-activated disinfection method, and this study will compare its performance with standard endodontic treatment protocols. The results are expected to provide clinical evidence regarding its potential benefits in reducing intracanal bacterial load and improving postoperative patient comfort.

Conditions

Root Canal Infection

Outcome Measures

Primary Outcomes (1)

• Reduction in intracanal bacterial load measured by quantitative PCR (qPCR)

  Intracanal bacterial load will be quantified using real-time quantitative polymerase chain reaction (qPCR). Samples will be collected at four predefined sampling points (S0-S3) using sterile #30 paper points inserted into the canal for 30 seconds. S0 (Baseline): After isolation and disinfection, before instrumentation S1: After access cavity preparation and working length determination S2: After root canal instrumentation S3 (Post-Intervention): After final irrigation protocol and photodynamic therapy (or sham procedure) Changes in bacterial DNA concentration (copy number/µL) from S0 to S3 will be compared between groups.

  Baseline (Day 1) to Immediately After Intervention (Day 1)

Secondary Outcomes (1)

• Postoperative pain levels measured using the Visual Analog Scale (VAS, 0-100)

  6 hours, 12 hours, 24 hours, Day 3, Day 5, and Day 7 after treatment.

Study Arms (2)

Control Group (Sham PDT)

PLACEBO COMPARATOR

Participants in this arm will receive the standard root canal irrigation protocol using 2.5% sodium hypochlorite and 17% EDTA. A sham photodynamic procedure will be performed by positioning the LED device near the tooth without light activation to simulate photodynamic therapy conditions. No Toluidine Blue O will be applied, and no active light irradiation will be performed

Procedure: Sham Photodynamic Therapy

Experimental Group (PDT)

EXPERIMENTAL

Participants in this arm will receive the standard root canal irrigation protocol followed by adjunctive photodynamic therapy. A 0.1 mg/mL Toluidine Blue O solution will be delivered into the canal and activated with a 630-nm LED light using an optical fiber for 60 seconds. This procedure will be performed after instrumentation and prior to final assessment sampling.

Drug: Toluidine Blue O (0.1 mg/mL); Device: 630-nm LED Light Device; Procedure: Photodynamic Therapy (PDT)

Interventions

Toluidine Blue O (0.1 mg/mL) DRUG

A 0.1 mg/mL toluidine blue O solution used as the photosensitizer for photodynamic therapy. The solution is placed into the root canal prior to 630-nm LED irradiation for activation.

Experimental Group (PDT)

630-nm LED Light Device DEVICE

A light-emitting diode device delivering 630-nm wavelength used to activate toluidine blue O during photodynamic therapy. The device is positioned near the tooth for 60 seconds.

Experimental Group (PDT)

Photodynamic Therapy (PDT) PROCEDURE

Application of 0.1 mg/mL toluidine blue O into the root canal, followed by activation with a 630-nm LED light source for 60 seconds as part of the experimental disinfection protocol.

Experimental Group (PDT)

Sham Photodynamic Therapy PROCEDURE

Placebo photodynamic procedure in which the LED device is positioned similarly but activated without delivering light energy; no toluidine blue O is applied.

Control Group (Sham PDT)

Eligibility Criteria

• Age: 18 Years - 65 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Patients aged between 18 and 65 years
• Presence of asymptomatic apical periodontitis with necrotic pulp in single-rooted maxillary or mandibular incisors, canines, or premolars
• Periapical Index (PAI) score ≥ 2
• Patients classified as ASA I (American Society of Anesthesiologists Physical Status Classification)
• Preoperative pain score \< 50 on the Visual Analog Scale (VAS)

You may not qualify if:

• Multi-rooted teeth
• Patients classified as ASA II or higher
• Pregnant women or those with suspected pregnancy
• Root canal curvature greater than 25° according to the Schilder method
• Patients diagnosed with generalized periodontitis
• Periodontal pocket depth \> 3 mm in the related tooth
• Use of analgesic medication within the past 72 hours
• Use of antibiotic therapy within the past month
• Presence of swelling and positive response to palpation/percussion tests

Sponsors & Collaborators

• Ataturk University: lead

Study Sites (1)

Atatürk University, Faculty of Dentistry, Department of Endodontics

Erzurum, Turkey (Türkiye)

Location

Related Publications (2)

• Er Karaoglu G, Ugur Ydin Z, Erdonmez D, Gol C, Durmus M. Efficacy of antimicrobial photodynamic therapy administered using methylene blue, toluidine blue and tetra 2-mercaptopyridine substituted zinc phthalocyanine in root canals contaminated with Enterococcusaecalis. Photodiagnosis Photodyn Ther. 2020 Dec;32:102038. doi: 10.1016/j.pdpdt.2020.102038. Epub 2020 Oct 1.

  PMID: 33010484 BACKGROUND

• Mozayeni MA, Vatandoost F, Asnaashari M, Shokri M, Azari-Marhabi S, Asnaashari N. Comparing the Efficacy of Toluidine Blue, Methylene Blue and Curcumin in Photodynamic Therapy Against Enterococcus faecalis. J Lasers Med Sci. 2020 Fall;11(Suppl 1):S49-S54. doi: 10.34172/jlms.2020.S8. Epub 2020 Dec 30.

  PMID: 33995969 BACKGROUND

MeSH Terms

Interventions

Tolonium Chloride; Photochemotherapy

Intervention Hierarchy (Ancestors)

Phenothiazines; Sulfur Compounds; Organic Chemicals; Heterocyclic Compounds, 3-Ring; Heterocyclic Compounds, Fused-Ring; Heterocyclic Compounds; Combined Modality Therapy; Therapeutics; Drug Therapy; Phototherapy

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: PARTICIPANT
• Masking Details: A single-blind design was implemented. Participants were unaware of their assigned intervention, and outcome assessors performing the microbiological analysis were masked to group allocation. A sham light application was used in the control group to preserve blinding
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Assistant Professor, Department of Endodontics, Faculty of Dentistry, Atatürk University

Model Details: Participants will be randomly assigned into two parallel groups (experimental and control) and will receive the allocated intervention only. Each participant will remain in the assigned group for the duration of the study.

Study Record Dates

• First Submitted: November 16, 2025
• First Posted: December 5, 2025
• Study Start: June 1, 2025
• Primary Completion: November 7, 2025
• Study Completion: March 1, 2026
• Last Updated: December 5, 2025

Record last verified: 2025-12

Data Sharing

• IPD Sharing: Will not share

Locations

TU (1)