Photobiomodulation, Photodynamic Therapy, and Clobetasol in the Treatment of Oral Lichen Planus.

Effectiveness of Photobiomodulation, Photodynamic Therapy, and Clobetasol in the Treatment of the Erosive Form of Oral Lichen Planus - a Randomized Clinical Trial.

This study aims to compare three treatment approaches for the erosive form of oral lichen planus, a chronic inflammatory condition that often causes pain, impaired oral function, and frequent relapses. Sixty adults with a confirmed diagnosis will be randomly assigned to photobiomodulation, Photodynamic Therapy, or topical clobetasol, which serves as the current standard of care. The project investigates how effectively each method promotes healing of erosive lesions, reduces pain, improves oral functions such as chewing and swallowing, and prevents recurrence after treatment. Before enrollment, participants will undergo microbiological testing, tissue autofluorescence assessment, and histopathological confirmation. Treatment will follow strict protocols tailored to each therapy type, with PBM applied twice weekly, PDT administered once weekly for six consecutive weeks using toluidine blue as a photosensitizer activated by a 635 nm diode laser, and clobetasol used twice daily for thirty days. Clinical outcomes will be measured using lesion size, standardized scoring systems, and patient-reported scales for pain and swelling. Follow up at one week, one month, and three months will document healing progress and relapse rates. Safety monitoring includes evaluation for infections and adverse reactions. The expected outcome is to determine which therapy provides the most effective, safe, and durable improvement. The study may offer evidence supporting laser based methods as alternatives that avoid the risks associated with long term steroid use.

Study Overview

• Status: Recruiting
• Conditions: Erosive Lichen Planus; Oral Lichen Planus; Mucosal Lesions
• Intervention / Treatment: Device: Photobiomodulation using 635 nm diode laser; Drug: Clobetasol propionate 0.05 percent topical application; Device: Photodynamic therapy - laser mucosal treatment

Detailed Description

The study investigates three therapeutic approaches for managing the erosive form of oral lichen planus, a chronic inflammatory disorder of the oral mucosa characterized by persistent mucosal damage, pain, and the risk of recurrent symptoms. The erosive phenotype is clinically significant because it often leads to functional limitations, such as difficulty eating, impaired tolerance of removable prostheses, and reduced quality of life. Standard therapy relies primarily on potent topical corticosteroids, yet this approach is frequently limited by incomplete remission, recurrence after withdrawal, and the potential for local adverse effects, including mucosal atrophy and secondary candidiasis. For these reasons, alternative treatment modalities have gained increasing clinical interest, particularly those based on light-based therapies capable of modulating cellular processes or removing pathologic tissue with minimal collateral injury. Photobiomodulation and Photodynamic Therapy represent two distinct applications of light energy. Photobiomodulation delivers low energy laser light that supports biological repair mechanisms, reduces inflammatory mediator activity, and enhances tissue regeneration without inducing thermal damage. PDT combines a photosensitizing agent with a light source of specific wavelength, which activates the photosensitizer to generate reactive oxygen species capable of selectively targeting pathologically altered tissue while limiting damage to surrounding healthy mucosa. This contributes to a reduction in lesion activity and supports mucosal recovery through localized cytotoxic and immunomodulatory mechanisms. Although each method has been investigated in smaller clinical series, direct comparisons among photobiomodulation, PDT, and topical corticosteroids remain limited, especially when applied to the erosive variant of oral lichen planus. The study follows a parallel group design with allocation governed by block randomization to maintain balanced group sizes. Participants undergo diagnostic workup before allocation to ensure accurate confirmation of the disease subtype and to exclude other mucosal disorders with overlapping features. Autofluorescence imaging is used as part of the diagnostic process to support precise selection of biopsy site and to assist in distinguishing inflammation from dysplasia or other pathology. Only patients with disease confined to the oral mucosa and without evidence of systemic illness that could influence healing potential proceed to treatment. Interventions are performed using standardized protocols that reflect current best practices for each modality. Photobiomodulation is delivered with a diode laser operating under controlled parameters designed to stimulate repair pathways. The PDT intervention uses toluidine blue as a photosensitizer applied under an occlusive dressing, followed by irradiation with a 635 nm diode laser to activate the photosensitizer and induce targeted cytotoxic effects within the affected mucosa. The control arm uses a topical corticosteroid formulation routinely employed in dental medicine for erosive lesions, with instructions provided to support maximal mucosal contact time. During the treatment period, clinicians document changes in lesion characteristics using standardized measurement tools that allow objective quantification of mucosal surface area and morphological alterations. Photographic records supplement clinical scoring to ensure consistency across follow up visits. Pain severity and functional disturbances are captured with validated numeric scales, supporting a comprehensive evaluation that includes both clinical and patient centered components. Follow up assessments take place after treatment completion to examine the durability of mucosal healing. Given that erosive oral lichen planus often recurs, these visits are critical to understanding whether any modality provides sustained remission. Monitoring includes microbiological evaluation to detect any changes in colonization patterns, such as the emergence of yeast species that may influence treatment response or cause secondary symptoms. Safety oversight focuses on identifying adverse reactions such as erythema, mucosal irritation, delayed healing, dyschromia, or any unexpected tissue responses. Light based methods are generally regarded as safe when applied within established energy ranges, yet ongoing surveillance helps detect rare events or individual sensitivities. The protocol outlines criteria for early discontinuation when significant symptom exacerbation or other concerning findings emerge. This study is structured to deliver high quality comparative data that can guide clinical decision making when standard therapy is insufficient, poorly tolerated, or contraindicated. By evaluating three therapeutically relevant modalities, the study seeks to determine which approach most effectively promotes epithelial recovery, reduces symptom burden, and supports functional comfort. Its focus on recurrence patterns adds an important dimension, as durable improvement is often challenging to achieve in erosive oral lichen planus. The results may clarify the advantages of low level laser applications, the immunomodulatory and antimicrobial properties of PDT, and the role of corticosteroids as a benchmark comparator. Photobiomodulation may demonstrate benefits related to noninvasiveness and absence of steroid related adverse effects. PDT may emerge as a precise alternative capable of controlling symptoms and accelerating mucosal healing through targeted photochemical action while avoiding systemic adverse effects. The study's methodology and extended observation window aim to support evidence based refinements to clinical protocols and promote therapeutic strategies aligned with patient comfort, safety, and long term disease control. The broader significance of the project lies in its potential to improve management of a chronic condition that has meaningful impact on daily activities and overall well being. By integrating structured clinical measurements, patient reported data, and advanced imaging methods, the study seeks to produce a comprehensive dataset that reflects contemporary standards in oral medicine research. The findings may pave the way for future work exploring predictors of treatment success, optimal photosensitizer concentrations and energy parameters for PDT, and potential combination approaches that incorporate both photobiomodulation and photodynamic tissue management.

• Study Type: Interventional
• Enrollment (Estimated): 60
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Jakub Fiegler-Rudol, PhD candidate; Phone Number: 0048531770099; Email: jakub.fieglerrudol@gmail.com
• Study Contact Backup: Name: Rafał Wiench, Professor, DMD, PhD; Phone Number: 0048574004884; Email: rwiench@sum.edu.pl

Study Locations

• Poland
  • Silesian Voivodeship
    • Zabrze, Silesian Voivodeship, Poland, 41-800
      • Recruiting
      • Department of Periodontology and Oral Mucosa Diseases
      • Contact: Rafał Wiench; Phone Number: +48 531 770 099; Email: rwiench@sum.edu.pl

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Be between 20 and 70 years old.
• Have histologically confirmed erosive or ulcerative oral lichen planus based on a biopsy.
• Have no active aerobic bacterial infection or oral fungal infection.
• Have had no treatment for OLP within the past 3 months.
• Provide written informed consent.

Exclusion Criteria:

• Systemic diseases or conditions such as uncontrolled diabetes (random glucose ≥200 mg/dl), cardiovascular failure, or a pacemaker.
• Autoimmune/connective tissue diseases such as lupus with positive ANA testing.
• Current or past cancer, graft-versus-host disease, or hematologic disorders (anemia, leukemia, lymphoma, bleeding disorders, hemophilia, von Willebrand disease).
• Enzymatic or metabolic disorders such as G6PD deficiency (favism) or porphyria.
• Viral hepatitis A, B, or C.
• Recent vaccinations (within the past 6 months).
• Use of medications known to trigger lichenoid reactions, including:
• Antihypertensives (beta-blockers, diuretics, ACE inhibitors, centrally acting agents).
• Oral antidiabetics (sulfonylureas).
• Metal-containing compounds (lithium, gold, arsenic, mercury).
• NSAIDs (e.g., ibuprofen).
• Antibiotics/chemotherapeutics (tetracyclines, sulfonamides).
• Pregnancy or breastfeeding (including up to 6 months post-lactation).
• Photosensitivity to UV light.
• Smoking more than 5 cigarettes per day.
• Lesions located adjacent to amalgam fillings or metal prosthetic restorations.
• Any degree of dysplasia on histopathology.
• Treatment for OLP within the last 3 months.
• Active oral fungal or bacterial infection at screening.
• Lack of consent to participate.

Study Plan

How is the study designed?

Design Details

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

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Photobiomodulation (PBM); Participants in this arm receive photobiomodulation using a 635 nm diode laser delivered in continuous mode. Energy parameters follow a fixed protocol with 4 J/cm² fluence, 100 mW power, and 15 seconds per treatment point using a noncontact technique. Applications are performed twice weekly until complete epithelial healing or a maximum of eight sessions. This arm evaluates the regenerative and anti-inflammatory effects of PBM for erosive oral lichen planus.	Device: Photobiomodulation using 635 nm diode laser; Photobiomodulation is delivered with a 635 nm diode laser in continuous mode at 100 mW, fluence 4 J/cm², and power density 0.2 W/cm². Each point is irradiated for 15 seconds using a noncontact technique with an 8 mm flat glass fiber tip and a 0.5 cm² spot size. Treatment points are spaced 2-3 mm apart over the lesion surface. Sessions are performed twice weekly until complete epithelial healing or for a maximum of eight sessions. This intervention aims to modulate inflammation and support mucosal repair in erosive oral lichen planus.; Other Names: PBM laser therapy; Low level laser therapy (LLLT)
Experimental: Topical Clobetasol 0.05 percent; Participants receive standard therapy with topical clobetasol propionate 0.05 percent. The medication is applied to clean, dry oral mucosa twice daily for thirty days following clinical guidelines for erosive oral lichen planus. This arm serves as the comparator for evaluating the effectiveness of laser-based treatments relative to established corticosteroid therapy.	Drug: Clobetasol propionate 0.05 percent topical application; Participants apply clobetasol propionate 0.05 percent directly to clean, dry oral mucosa twice daily for thirty days. The medication is used according to standard clinical practice for erosive oral lichen planus. The formulation serves as the active comparator to evaluate how laser-based treatments perform relative to conventional corticosteroid therapy. Participants are instructed to avoid eating, drinking, or rinsing for at least 30 minutes after application to ensure adequate mucosal contact.; Other Names: Topical corticosteroid
Experimental: Photodynamic Laser Therapy - TBO mediated; Participants in this arm undergo Photodynamic Therapy using toluidine blue as a photosensitizer activated by a 635 nm diode laser. The protocol applies the photosensitizer in gel form under an occlusive dressing for ten minutes, followed by point-by-point irradiation at a fluence of 120 J/cm² using a glass fiber tip of 8 mm diameter, targeting pathologically altered mucosal tissue while minimizing damage to surrounding healthy epithelium. Treatment is performed once weekly for six consecutive sessions. This arm evaluates whether PDT-mediated photochemical action supports lesion resolution, symptom reduction, and sustained remission in erosive oral lichen planus.	Device: Photodynamic therapy - laser mucosal treatment; Photodynamic Therapy is performed using toluidine blue gel as a photosensitizer, applied to the affected mucosal surface under an occlusive dressing for ten minutes. Following removal of the dressing and excess photosensitizer, irradiation is carried out using a 635 nm diode laser (Smart M®, Lasotronix) operating in continuous-wave mode at an output power of 400 mW and a power density of 0.8 W/cm². A flat glass fiber tip of 8 mm diameter is used in a noncontact mode at a distance of approximately 1 mm from the lesion surface. Irradiation is applied point by point at a fluence of 120 J/cm² per point, with the duration of each point irradiation set at 2 minutes and 32 seconds; the total number of points and overall session duration are determined by lesion extent. Following irradiation, the photosensitizer is left in place for an additional three minutes before removal by oral rinsing with water. Sessions are conducted once weekly for six consecutive treatments. This intervention evaluat

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in erosive oral lichen planus lesion severity using the REA score	Lesion severity will be measured using the REA scoring system, which evaluates the reticular (R), atrophic (A), and erosive (E) components of oral lichen planus. Each component is quantified from standardized lesion tracings and clinical measurements taken during oral examinations. Scores are calculated according to the protocol formula: REA = (R × 1) + (A × 1.5) + (E × 2). The change in total REA score from baseline reflects the therapeutic effect of each intervention on healing of erosive lesions.	Baseline to 1 week after completion of assigned treatment
Efficacy Index (EI) for overall treatment response	The Efficacy Index (EI) quantifies overall clinical improvement using the formula defined in the study protocol: EI = [(total REA score before treatment - total REA score after treatment) ÷ total REA score before treatment] × 100 percent. EI will be used to categorize outcomes as complete healing, significant improvement, moderate improvement, mild improvement, or no improvement.	Baseline to 1 week after completion of assigned treatment
Improvement in pain intensity (NB)	NB represents the percentage improvement in pain based on the Visual Analogue Scale (VAS). It is calculated using the formula: NB = [(VAS before treatment - VAS after treatment) ÷ VAS before treatment] × 100 percent. NB will classify improvement as complete, significant, moderate, mild, or absent.	Baseline to 1 week after completion of assigned treatment

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in lesion size measured in mm²	Lesion surface area will be measured using transparent millimeter-grid foil applied to the mucosal surface. Boundaries of each lesion will be traced and the total area calculated. Changes from baseline will be compared across treatment groups.	Baseline, 1 week, 1 month, and 3 months after treatment completion
Change in pain intensity using the Visual Analogue Scale (VAS)	Pain will be assessed using a 0-10 VAS scale. Participants will report pain at baseline and at follow-up visits. Improvement will be quantified using the protocol-defined formula for pain reduction (NB).	Baseline, 1 week, 1 month, and 3 months after treatment completion
Change in swelling or oral discomfort (subjective assessment)	Participants will evaluate swelling or discomfort on a 0-10 numeric scale. Improvement will be calculated using the protocol-defined formula (NO) to quantify reduction of symptoms after treatment.	Baseline, 1 week, 1 month, and 3 months after treatment completion
Change in clinical grade using the Thonprasom scale (0-5)	Clinical severity of oral lichen planus will be evaluated using the Thonprasom grading system. Each lesion will be assigned a grade based on extent and morphology. Change in score over time will be used to assess therapeutic response.	Baseline, 1 week, 1 month, and 3 months after treatment completion
Change in mycological status of oral mucosa	Oral swabs will undergo mycological analysis to detect presence of Candida species before and after treatment. Results will identify whether any intervention increases or reduces fungal colonization or secondary infection risk.	Baseline and 1 week after treatment completion

Collaborators and Investigators

• Sponsor: Medical University of Silesia
• Investigators: Study Chair: Dariusz Skaba, Department of Periodontolody and Oral Mucosa Diseases, Medical University of Silesia; Principal Investigator: Jakub Fiegler-Rudol, Department of Periodontolody and Oral Mucosa Diseases, Medical University of Silesia; Study Director: Rafał Wiench, Department of Periodontolody and Oral Mucosa Diseases, Medical University of Silesia

Study record dates

Study Major Dates

• Study Start (Actual): December 1, 2025
• Primary Completion (Estimated): October 1, 2026
• Study Completion (Estimated): November 1, 2026

Study Registration Dates

• First Submitted: December 1, 2025
• First Submitted That Met QC Criteria: December 1, 2025
• First Posted (Actual): December 12, 2025

Study Record Updates

• Last Update Posted (Actual): April 30, 2026
• Last Update Submitted That Met QC Criteria: April 24, 2026
• Last Verified: December 1, 2025

More Information

Terms related to this study

• Keywords: laser; PDT; steroids; lichen planus; Oral lichen planus; Photobiomodulation therapy
• Additional Relevant MeSH Terms: Mouth Diseases; Stomatognathic Diseases; Lichenoid Eruptions; Skin Diseases, Papulosquamous; Skin Diseases; Skin and Connective Tissue Diseases; Lichen Planus, Oral; Lichen Planus; Hormones; Hormones, Hormone Substitutes, and Hormone Antagonists; Therapeutics; Equipment and Supplies; Lasers; Optical Devices; Radiation Equipment and Supplies; Laser Therapy; Phototherapy; Lasers, Semiconductor; Low-Level Light Therapy; Adrenal Cortex Hormones
• Other Study ID Numbers: BNW/NWN/0052/KB1/124/25; BNW-1-151/N/5/K (Other Grant/Funding Number: Medical University of Silesia (Internal Grant))

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Individual participant data will not be shared because the study involves sensitive clinical information and the protocol does not include provisions for external data distribution. Data access is limited to the research team to protect participant privacy and confidentiality.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No