Erbium-doped Yttrium Aluminum Garnet (Er:YAG) Laser vs Conventional Ceramic Bracket Debonding: A Split-Mouth Clinical Trial

Evaluation of Enamel Surface and Pulpal Temperature for Ceramic Bracket Removal Using Two Laser Intensities Versus Conventional Technique: A Split-Mouth Clinical Study

This randomized split-mouth clinical trial evaluates enamel surface preservation, pulpal temperature variation, and patient-reported discomfort during ceramic orthodontic bracket removal using two Erbium-doped yttrium aluminum garnet (Er:YAG) laser parameter settings compared to conventional mechanical debonding. Pulpal temperature is monitored in real time using a thermocouple device. Enamel integrity is assessed using the Adhesive Remnant Index (ARI) under 40× magnification. The study aims to determine optimal laser parameters ensuring safe and conservative bracket removal.

Study Overview

• Status: Active, not recruiting
• Conditions: Pain; Healthy Adult; Orthodontic Brackets; Laser; Temperature Change
• Intervention / Treatment: Procedure: Conventional Mechanical Debonding; Device: Er:YAG Laser - Parameter 1; Device: Er:YAG Laser - Parameter 2

Detailed Description

Orthodontic bracket debonding must restore enamel close to its pretreatment condition while minimizing iatrogenic damage. Ceramic brackets demonstrate high bond strength and are associated with increased enamel fracture risk during conventional removal. Laser-assisted debonding has been proposed to reduce mechanical stress by softening the adhesive interface. However, concerns remain regarding pulpal temperature elevation and enamel surface alteration.

This randomized split-mouth clinical trial compares two Er:YAG laser parameter settings with conventional plier debonding. Pulpal temperature variation will be measured using a thermocouple inserted into the pulp chamber. Enamel surface evaluation will be performed using 40× magnification to assess ARI score. Pain perception will be recorded using a visual analog scale (VAS). The study aims to optimize laser parameters while ensuring biological safety and enamel preservation.

This split-mouth clinical trial includes 10 patients (100 maxillary teeth, teeth 15-25). Brackets are randomized by quadrant into:

Laser Parameter 1 (Er:YAG, 4 W, 400 mJ, 10 Hz)

Laser Parameter 2 (Er:YAG, 4.5 W, 300 mJ, 15 Hz)

Conventional mechanical debonding

Primary outcome: pulpal temperature variation (∆T). Secondary outcomes: ARI score and pain perception (VAS).

Laser irradiation is performed using LightWalker II ST-E Pro+ (Fotona, 2940 nm), non-contact mode, 45° angle, 1 cm distance, MicroShort pulse (MSP) mode, air=1, water=1, 10-15 seconds scanning.

• Study Type: Interventional
• Enrollment (Actual): 10
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Lebanon
  • Beirut, Lebanon, 0000
    • Universite Saint Joseph, Faculte de Medecine

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Age 20-30 years
• Completed orthodontic treatment
• Maxillary teeth (15-25) bonded with 3M Clarity™ ceramic brackets
• No analgesic use within 7 days
• Good systemic health

Exclusion Criteria:

• Smokers
• Systemic diseases affecting oral health
• Teeth with restorations or crowns
• Pulp necrosis or infection
• Medications affecting pulp vascular dynamics

Study Plan

How is the study designed?

Design Details

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

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Er:YAG Laser - Parameter 1; Quadrants randomized to receive ceramic bracket removal using Er:YAG laser (Parameter Set 1) within a split-mouth design. Each participant serves as their own control, with the contralateral quadrant receiving conventional debonding.	Procedure: Conventional Mechanical Debonding; Ceramic bracket removal using orthodontic debonding pliers (3M™ Unitek™ Debonding Instrument) applying controlled torsional force to bracket wings according to standard clinical protocol.
Experimental: Er:YAG Laser - Parameter 2; Quadrants randomized to receive ceramic bracket removal using Er:YAG laser (Parameter Set 2) within a split-mouth design. Each participant serves as their own control, with the contralateral quadrant receiving conventional debonding.	Procedure: Conventional Mechanical Debonding; Ceramic bracket removal using orthodontic debonding pliers (3M™ Unitek™ Debonding Instrument) applying controlled torsional force to bracket wings according to standard clinical protocol.
Experimental: Conventional Mechanical Debonding; Quadrants randomized to receive conventional ceramic bracket removal using orthodontic debonding pliers. In the split-mouth design, each participant also receives laser-assisted debonding on the contralateral quadrant	Device: Er:YAG Laser - Parameter 1; Er:YAG laser (LightWalker II ST-E Pro+, Fotona, 2940 nm wavelength) applied in non-contact mode at 4 W average power, 400 mJ pulse energy, 10 Hz frequency, MSP mode (100 µs pulse duration), air=1 and water=1 settings. Laser applied at 45° angle, 1 cm distance, scanning method for 10-15 seconds until bracket detachment.; Device: Er:YAG Laser - Parameter 2; Er:YAG laser (LightWalker II ST-E Pro+, Fotona, 2940 nm wavelength) applied in non-contact mode at 4.5 W average power, 300 mJ pulse energy, 15 Hz frequency, MSP mode (100 µs pulse duration), air=1 and water=1 settings. Laser applied at 45° angle, 1 cm distance, scanning method for 10-15 seconds until bracket detachment.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Pulpal Temperature Variation (∆T)	Real-time pulp chamber temperature measured using a calibrated K-type thermocouple during laser irradiation. Temperature change recorded in degrees Celsius (°C).	During laser assisted bracket removal procedure

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Adhesive Remnant Index (ARI)	Microscopic evaluation at 40× magnification using Artun and Bergland scale (0-3).	Immediately after bracket removal
Pain Perception (VAS)	Patient-reported pain measured using a 10 cm Visual Analog Scale (0-10).	Immediately after each quadrant debonding

Collaborators and Investigators

• Sponsor: Saint-Joseph University

Study record dates

Study Major Dates

• Study Start (Actual): May 1, 2025
• Primary Completion (Estimated): April 30, 2026
• Study Completion (Estimated): May 30, 2026

Study Registration Dates

• First Submitted: February 24, 2026
• First Submitted That Met QC Criteria: April 3, 2026
• First Posted (Actual): April 8, 2026

Study Record Updates

• Last Update Posted (Actual): April 8, 2026
• Last Update Submitted That Met QC Criteria: April 3, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Keywords: pain assessment; ceramic brackets; tooth enamel; orthodontic debonding; enamel integrity; pulpal temperature; adhesive remnant index; Erbium-doped Yttrium Aluminum Garnet Laser
• Additional Relevant MeSH Terms: Neurologic Manifestations; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Pain
• Other Study ID Numbers: CRFMD A32/35 - CER-2025-233

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

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