Photobiomodulation Effect on Vietnamese Orthodontic Patients

Photobiomodulation Effect on Vietnamese Orthodontic Patients: A Randomized Clinical Trial

Since most orthodontic cases endure for 2 to 3 years or longer, patients are at a high risk of inflammatory root resorption and prolonged orthodontic pain, which is a common and unwanted side effect of their treatment. Photobiomodulation therapy utilizing light-emitting diodes (LEDs) offers a non-pharmacological approach for pain management, acceleration of tooth movement, and reduction of root resorption risk.

This randomized, placebo-controlled clinical trial aims to evaluate the effects of LED photobiomodulation on pain alleviation, acceleration of tooth movement, and mitigation of root resorption risk during orthodontic treatment. A total of 16 Vietnamese participants, aged 11 to 30 years, receiving fixed orthodontic treatment were randomly assigned to either an intervention group (LED therapy) or a control group (placebo). Patients were assessed at four consecutive follow-up visits at monthly intervals. Canine movement was measured by superimposing patients' 3D scans collected at the four follow-ups in 3D Slicer. At each visit, their pain intensity was measured using the Visual Analog Scale (VAS) to establish the baseline for that follow-up (0 hour), and then measured again at 24 hours and 48 hours post-visit. Furthermore, during each visit, the investigator collected patients' saliva and gingival crevicular fluid (GCF) to extract dentin sialoprotein (DSP), a biomarker of root resorption in humans.

The primary outcome is the difference in pain assessments between the intervention and control groups, the mobility of canines across groups, and the concentration of dentin sialoprotein in gingival crevicular fluid and saliva.

Study Overview

• Status: Completed
• Conditions: Pain Management; Root Resorption; Tooth Movement; Orthodontic
• Intervention / Treatment: Device: Placebo LED device; Device: LED device

Detailed Description

During the orthodontic treatment period, patients must endure various discomforts, such as the risk of inflammatory root resorption and frequent pain, which typically occur due to the body's inflammatory response to the applied forces. Pain is commonly managed with non-steroidal anti-inflammatory drugs (NSAIDs) or acetaminophen; however, these medications may induce adverse effects and potentially inhibit tooth movement. Photobiomodulation (PBM) therapy using light-emitting diodes (LEDs) has emerged as a non-pharmacological approach that may reduce pain, enhance tooth movement, and lower the risk of root resorption.

The objective of this randomized, placebo-controlled clinical trial is to evaluate the effects of LED PBM on pain reduction, enhancement of tooth movement, and mitigation of root resorption risk during orthodontic treatment. Sixteen participants aged 11 to 30 years undergoing fixed orthodontic treatment were randomly assigned to either the intervention group or the placebo group. In the intervention group, patients used the LED device for 10 minutes per day (5 minutes for the upper arch and 5 minutes for the lower arch) every day. In the placebo group, patients used a sham LED device (without a charging case) following the same procedure, 10 minutes per day. Patients in both groups were blinded to the light status while wearing the device. After finishing the aligning and leveling stage with Nickel and Titanium (NiTi) arch wires, during the phase of canine distalization with stainless steel arch wires, patients were assessed at four consecutive follow-up visits, scheduled at monthly intervals.

Canine movement was measured by superimposing sequential 3D digital scans obtained over these four visits using 3D Slicer software. Saliva and gingival crevicular fluid (GCF) samples were collected at each follow-up visit to measure dentin sialoprotein (DSP), a biomarker of root resorption in humans. Additionally, at each visit, patients' pain intensity was measured using the Visual Analog Scale (VAS) to establish the baseline for that follow-up (0 hour), and then measured again at 24 hours and 48 hours post-visit. The primary outcomes are differences between groups in canine displacement, pain intensity, and DSP concentration in both saliva and GCF.

The findings of this study may support the clinical application of LED PBM as a safe, non-invasive, and drug-free adjunctive therapy to improve patient comfort and reduce treatment-related risks during orthodontic care, particularly in Vietnamese patients.

• Study Type: Interventional
• Enrollment (Actual): 16
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Vietnam
  • Ho Chi Minh City, Vietnam
    • Faculty of Dentistry, University of Medicine and Pharmacy in Ho Chi Minh city

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Patients aged 11-30 years old who were required to undergo extraction of four premolars for orthodontic purposes.
• Four canines erupted in both arches.
• No active caries, no gingivitis, or periodontal disease was diagnosed through clinical examination and panoramic X-ray.
• No history of previous orthodontic treatment.
• No abnormality in tooth shape, number, or size.

Exclusion Criteria:

• Patients who smoked, had systemic diseases, and/or were using medications that could affect pain sensation.
• Patients who are diagnosed with severe root resorption based on their panorama X-ray image.

Study Plan

How is the study designed?

Design Details

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

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Placebo Comparator: Sham LED device; Patients wore the sham LED device without charging case for 10 minutes daily (5 minutes for the maxillary arch and 5 minutes for the mandibular arch at the same time each day). Patients did not know that LED device could emit light.	Device: Placebo LED device; Sham LED device contains no charging case (emiting no light)
Experimental: 850nm LED device; Patients wore the LED device which emit near-infrared ligth at 850nm wavelength for 10 minutes daily (5 minutes for the maxillary arch and 5 minutes for the mandibular arch at the same time each day. Patients did not know that LED device could emit light.	Device: LED device; LED device emits near-infrared ligth at 850nm wavelength.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Dentin sialoprotein (DSP) levels in saliva and gingival crevicular fluid	The primary endpoint is the difference in dentin sialoprotein (DSP) levels between the LED photobiomodulation group and the placebo group. DSP concentrations will be extracted from saliva and gingival crevicular fluid samples collected at four prespecified time points: Pre-treatment; Baseline (initiation of canine distalization); 1-month follow-up; 2-month follow-up DSP levels will be measured using Enzyme-Linked Immunosorbent Assay (ELISA). The primary comparison is the mean change in DSP levels across the follow-up period between the intervention and placebo groups, to evaluate the biomarker response associated with orthodontically induced inflammatory root resorption.	Pre-treatment, Baseline, 1-month follow-up, and 2-month follow-up.
Rate of canine distalization (mm/month) compared across monthly intervals	Canine movement will be measured in millimeters by superimposing three-dimensional digital models of the maxilla and mandible. Digital models for participants in both study groups will be collected at the following visits: Baseline (initiation of canine distalization); 1-month follow-up; 2-month follow-up; 3-month follow-up Measurements will be performed using 3D Slicer software. The primary endpoint is the difference between the LED photobiomodulation group and the placebo group in the amount of canine movement observed during each monthly interval: Baseline to 1-month; 1-month to 2-month; 2-month to 3-month	Baseline to 1-month, 1-month to 2-month, and 2-month to 3-month intervals.
Change in pain intensity (VAS scores)	Pain intensity will be measured using a 100-mm Visual Analog Scale (VAS), illustrated as a 100mm ruler on questionnaire papers, where 0 represents no pain and 100 represents the worst imaginable pain. The primary endpoint is the difference in mean VAS scores between the LED photobiomodulation group and the placebo group. VAS scores will be recorded immediately at the time of each clinical visit. Measurements will be collected at four prespecified visits: Baseline (initiation of canine distalization); 1-month follow-up; 2-month follow-up; 3-month follow-up	Immediately (0 hour) at Baseline, 1-month, 2-month, and 3-month follow-up visits.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Time to peak pain intensity	Time to peak pain intensity is defined as the time point (0 hour, 24 hours, or 48 hours) at which each participant records the highest Visual Analog Scale (VAS) score following initiation of canine distalization. Assessments will be performed at four scheduled visits: Baseline, 1-month, 2-month, and 3-month follow-up. The outcome will compare the proportion of participants whose peak pain occurs at each time point between the LED photobiomodulation group and the placebo group.	0 hour, 24 hours, and 48 hours after treatment initiation at Baseline, 1-month, 2-month, and 3-month visits.

Collaborators and Investigators

• Sponsor: University of Medicine and Pharmacy at Ho Chi Minh City
• Investigators: Principal Investigator: Thanh TN Cao, MSc, University of Medicine and Pharmacy in Ho Chi Minh city

Study record dates

Study Major Dates

• Study Start (Actual): April 20, 2022
• Primary Completion (Actual): October 10, 2025
• Study Completion (Actual): October 10, 2025

Study Registration Dates

• First Submitted: November 18, 2025
• First Submitted That Met QC Criteria: November 28, 2025
• First Posted (Estimated): December 11, 2025

Study Record Updates

• Last Update Posted (Actual): December 19, 2025
• Last Update Submitted That Met QC Criteria: December 13, 2025
• Last Verified: November 1, 2025

More Information

Terms related to this study

• Keywords: pain; photobiomodulation; LED; toothmovement; cumulative effect; rootresoption
• Additional Relevant MeSH Terms: Neurologic Manifestations; Stomatognathic Diseases; Nervous System Diseases; Tooth Diseases; Neurobehavioral Manifestations; Perceptual Disorders; Tooth Resorption; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Pain; Agnosia; Root Resorption
• Other Study ID Numbers: 22230-DHYD

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: The results of my primary outcomes including VAS scores of intervention and control groups
• IPD Sharing Time Frame: Start day: October 2025 End day: October 2027
• IPD Sharing Access Criteria: Students and researchers. Through my email address, thanh.caothuynhat@gmail.com
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No