An interventional study of 450 nm Blue Diode Laser and Blue Light-Emitting Diode Lamp in Tooth Discoloration, sponsored by Misr University for Science and Technology. Completed at 1 site in Egypt. Open to participants aged 18 Years to 25 Years. Per ClinicalTrials.gov, last updated 2026-10-13.
Sponsored by Misr University for Science and Technology · Not applicable, Interventional, and Treatment
Tooth discoloration is commonly managed using in-office dental bleaching. This randomized clinical trial compared the efficacy and safety of activating the same 35% hydrogen peroxide bleaching gel with either a 450 nm blue diode laser or a conventional blue light-emitting diode lamp. Forty participants aged 18 to 25 years were randomly assigned in a 1:1 ratio to one of the two interventions. The primary outcome was postoperative tooth hypersensitivity immediately after treatment. Secondary outcomes included immediate tooth-color change, color stability at 4 weeks, 8 weeks, and 6 months, gingival irritation, and patient satisfaction. Participants and outcome assessors were blinded to group allocation, whereas the treating operator could not be blinded because the devices were visibly different.
This participant- and outcome-assessor-blinded, parallel-group randomized clinical trial evaluated two methods of photoactivating an in-office dental bleaching agent. Participants underwent medical and dental assessment and professional gingival decontamination one week before bleaching.
Participants were assigned to either a 450 nm blue diode laser group or a blue LED group. Both groups received a 35% hydrogen peroxide bleaching gel. In the laser group, the gel was activated using a TRIPLO 450 nm blue diode laser operated at 1.5 W in continuous-wave mode with an 8 mm handpiece tip for 30 seconds per tooth. Three bleaching cycles were performed, with the gel removed after each cycle. In the comparator group, the same bleaching gel was activated using the BlancOne ARCUS blue LED lamp according to the manufacturer's protocol.
Tooth color was assessed before treatment, immediately after treatment, and at 4 weeks, 8 weeks, and 6 months. Postoperative hypersensitivity was assessed immediately after treatment using a visual analogue scale. Gingival irritation and participant satisfaction were assessed using verbal rating measures. Participants, questionnaire collectors, tooth-color assessors, and the statistical analyst were blinded to group allocation. The operator administering the interventions was not blinded.
107 studies on the registry are indexed under Tooth Discoloration; 19 are open to participants now.
This study's enrollment of 40 is below the median of 46 across 99 interventional studies indexed under Tooth Discoloration.
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Participants underwent in-office tooth bleaching with 35% hydrogen peroxide gel activated using a 450 nm blue diode laser. The laser was operated at 1.5 W in continuous-wave mode through an 8 mm handpiece tip for 30 seconds per tooth. Three bleaching cycles were performed, with the gel removed after each cycle.
Device: 450 nm Blue Diode Laser · Drug: 35% Hydrogen Peroxide Dental Bleaching Gel
Participants underwent in-office tooth bleaching with the same 35% hydrogen peroxide gel activated using a blue LED lamp according to the manufacturer's recommended protocol. The LED was placed at 5-10cm from the mouth for a period of 24 minutes. The bleaching gel was simultaneously activated on both arches, including the sides, without any operator intervention. The bleaching session consisted of three cycles. The gel was photoactivated for 8 minutes during each cycle.
Device: Blue Light-Emitting Diode Lamp · Drug: 35% Hydrogen Peroxide Dental Bleaching Gel
A 450 nm blue diode laser was used to activate the dental bleaching gel. The device was operated at 1.5 W in continuous-wave mode using a therapy handpiece with an 8 mm tip connected to an optical fiber. Irradiation was delivered for 30 seconds per tooth. Three bleaching cycles were performed.
Also known as: TRIPLO, Medency
A blue light-emitting diode lamp was used to activate the dental bleaching gel. The device was operated according to the manufacturer's recommended protocol, The lamp was oriented perpendicularly to the teeth at a distance of 5-10 cm from the mouth to guarantee adequate airflow. The bleaching session consisted of three cycles. The gel was photoactivated for 8 minutes during each cycle.
Also known as: BlancOne ARCUS
The same 35% hydrogen peroxide dental bleaching gel was applied in both study arms. The bleaching session consisted of three cycles. The gel was photoactivated for 8 minutes during each cycle.
Also known as: BlancOne ULTRA+
Postoperative Tooth Hypersensitivity Assessed Using a Visual Analogue Scale
Participants rated tooth hypersensitivity using a visual analogue scale. The VAS outlines six The patients were asked to select the option that most accurately reflects their amount of discomfort or pain experienced. The scores of 0 (no pain), 1(little), 2 (mild), 3 (moderate), 4 (severe), 5 (very severe), and 6 (unbearable) were sequentially awarded to each face, representing an increasing level of pain.
Time frame: Immediately after completion of the in-office bleaching session.
Change From Baseline in Visual Tooth Shade Immediately After Bleaching
Tooth shade was assessed using the VITA Bleachedguide 3D-Master® classic guide. Shade tabs were converted into ordered numerical shade units. The change from baseline to immediately after treatment was calculated, with a greater reduction in shade units indicating greater whitening.
Time frame: Tooth color assessments were conducted at baseline, immediately post-bleaching treatment.
Spectrophotometric Tooth Color Change Immediately After Bleaching
Tooth color was measured using a spectrophotometer at baseline and immediately after treatment. Color difference was calculated using the metric ΔE\*ab, ΔE00. Higher values indicated a greater color difference from baseline.
Time frame: Baseline and immediately after the bleaching session.
Tooth Color Stability During the Six-Month Follow-Up
Tooth shade was assessed immediately after treatment and at 4 weeks, 8 weeks, and 6 months. Shade regression was calculated as the change between the immediate post-treatment shade and each follow-up measurement. Greater shade regression indicated greater loss of the whitening effect.
Time frame: Immediately after treatment and at 4 weeks, 8 weeks, and 6 months.
Spectrophotometric Color Stability During Follow-Up
Spectrophotometric tooth-color measurements were obtained immediately after treatment and at 4 weeks, 8 weeks, and 6 months. Color stability was assessed by calculating the change in spectrophotometric shade scores between successive assessment periods. Greater positive changes during follow-up indicated greater shade regression and loss of the whitening effect.
Time frame: Immediately after treatment and at 4 weeks, 8 weeks, and 6 months.
Participant Satisfaction With the Bleaching Treatment
Participants rated their overall satisfaction using a verbal rating scale with the following scores: 1 for extremely satisfied, 2 for satisfied, 3 not satisfied.
Time frame: At the end of follow-up, 6 months after treatment.
Plan to share: Undecided
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Misr University for Science and Technology