Photodynamic Therapy as an Adjunct in Periodontal Treatment (PDT-PERIO)

June 2, 2026 updated by: Gabriela Guadalupe Zambrano Manzaba, Universidad Catolica Santiago de Guayaquil

Clinical Evaluation of Photodynamic Therapy as an Adjunct to Scaling and Root Planing in the Treatment of Periodontal Disease: A Split-Mouth Randomized Controlled Clinical Trial

This study aims to evaluate the clinical effectiveness of antimicrobial photodynamic therapy (aPDT) as an adjunct to scaling and root planing (SRP) in the treatment of periodontitis. A split-mouth design will be used, in which one hemiarch receives conventional SRP and the contralateral hemiarch receives SRP combined with aPDT. Clinical periodontal parameters, including probing pocket depth (PPD), clinical attachment level (CAL), bleeding on probing (BOP), plaque index (PI), and gingival index (GI), will be assessed at baseline and 30 days after treatment. The study seeks to determine whether adjunctive aPDT improves periodontal outcomes compared with conventional non-surgical periodontal therapy alone.

Study Overview

Detailed Description

Periodontitis is a chronic inflammatory disease characterized by the destruction of the supporting tissues of the teeth and is one of the leading causes of tooth loss worldwide. Scaling and root planing (SRP) is considered the gold standard non-surgical treatment; however, complete elimination of periodontal pathogens may be difficult in deep periodontal pockets and anatomically complex sites.

Antimicrobial photodynamic therapy (aPDT) has emerged as a minimally invasive adjunctive treatment. This technique combines a photosensitizing agent, toluidine blue O, with low-level laser irradiation to produce reactive oxygen species capable of destroying periodontal pathogens while minimizing damage to host tissues.

This study will be conducted at the Dental Clinic of the Universidad Católica de Santiago de Guayaquil, Ecuador. Thirty adult patients diagnosed with periodontitis will be enrolled. A split-mouth randomized design will be used, with one hemiarch receiving SRP alone (control) and the contralateral hemiarch receiving SRP plus aPDT (test group).

Clinical parameters including probing pocket depth (PPD), clinical attachment level (CAL), bleeding on probing (BOP), plaque index (PI), and gingival index (GI) will be recorded at baseline and at 30-day follow-up. The primary objective is to compare the clinical effectiveness of adjunctive aPDT versus conventional SRP alone in improving periodontal health outcomes.

The study has been approved by the Ethics Committee for Research in Human Subjects of the Universidad Católica de Santiago de Guayaquil (CEISH-UCSG) and will be conducted in accordance with ethical principles for human research.

Study Type

Interventional

Enrollment (Estimated)

30

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Locations

    • Guayas
      • Guayaquil, Guayas, Ecuador, 090101
        • Dental School, Catholic University of Santiago de Guayaquil (UCSG)
        • Sub-Investigator:
          • HECTOR A LEMA GUTIERREZ, DDS
        • Contact:
        • Contact:
        • Sub-Investigator:
          • PABLO M REYES CUENCA, DDS
        • Principal Investigator:
          • GABRIELA GUADALUPE ZAMBRANO MANZABA, DDS

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Adults aged 18 to 65 years.
  • Diagnosis of Stage I, II, III, or IV periodontitis according to the 2018 World Workshop Classification.
  • Presence of at least two hemiarches with periodontal pockets ≥5 mm suitable for a split-mouth design.
  • Systemically healthy individuals.
  • No periodontal treatment received within the previous 6 months.
  • No use of antibiotics, anti-inflammatory drugs, or antiseptic mouth rinses within the previous 3 months.
  • Ability and willingness to provide written informed consent and attend follow-up visits.

Exclusion Criteria:

  • Uncontrolled systemic diseases that may affect healing or immune response.
  • Use of antibiotics, corticosteroids, or immunosuppressive medications within the previous 3 months.
  • Active smokers consuming more than 10 cigarettes per day.
  • Pregnant or breastfeeding women.
  • Presence of dental implants, defective restorations, or teeth with Grade III mobility in the selected study sites.
  • Known allergy to toluidine blue O or any component of the photosensitizer.
  • Individuals unable or unwilling to attend the 30-day follow-up visit.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Double

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Active Comparator: Scaling and Root Planing (SRP)
Hemiarch treated with conventional non-surgical periodontal therapy consisting of scaling and root planing alone.
Conventional non-surgical periodontal therapy performed using ultrasonic and manual instrumentation to remove subgingival biofilm and calculus.
Experimental: Scaling and Root Planing Plus Antimicrobial Photodynamic Therapy (SRP + aPDT)
Hemiarch treated with conventional scaling and root planing combined with adjunctive antimicrobial photodynamic therapy using toluidine blue O and low-level laser irradiation.
Conventional non-surgical periodontal therapy performed using ultrasonic and manual instrumentation to remove subgingival biofilm and calculus.
Adjunctive antimicrobial photodynamic therapy using toluidine blue O as photosensitizer activated with a 650 nm low-level laser following scaling and root planing.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Change in Probing Pocket Depth (PPD)
Time Frame: Baseline and 30 Days
Mean change in probing pocket depth (PPD), measured in millimeters using a UNC-15 periodontal probe, comparing baseline and 30-day follow-up between treatment groups.
Baseline and 30 Days

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Change in Clinical Attachment Level (CAL)
Time Frame: Baseline and 30 Days
Mean change in clinical attachment level (CAL), measured in millimeters from the cemento-enamel junction to the bottom of the periodontal pocket.
Baseline and 30 Days
Change in Bleeding on Probing (BOP)
Time Frame: Baseline and 30 Days
Percentage of sites presenting bleeding on probing after periodontal examination.
Baseline and 30 Days
Change in Plaque Index (PI)
Time Frame: Baseline and 30 Days
Percentage of dental surfaces with visible plaque assessed using the O'Leary plaque index.
Baseline and 30 Days
Change in Gingival Index (GI)
Time Frame: Baseline and 30 Days
Mean gingival index score assessed according to the Löe and Silness criteria.
Baseline and 30 Days

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

July 28, 2026

Primary Completion (Estimated)

August 30, 2026

Study Completion (Estimated)

September 27, 2026

Study Registration Dates

First Submitted

June 2, 2026

First Submitted That Met QC Criteria

June 2, 2026

First Posted (Actual)

June 8, 2026

Study Record Updates

Last Update Posted (Actual)

June 8, 2026

Last Update Submitted That Met QC Criteria

June 2, 2026

Last Verified

June 1, 2026

More Information

Terms related to this study

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

UNDECIDED

IPD Plan Description

A decision regarding the sharing of individual participant data (IPD) has not yet been made. Data sharing plans will be determined after study completion, publication of primary results, and in accordance with institutional policies, ethical approvals, participant confidentiality requirements, and applicable regulations.

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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