Characterization and effectiveness of a violet LED light for in-office whitening

• Published in: Clinical oral investigations Vol. 26; no. 5; pp. 3899 - 3910
• Main Authors: Kury, Matheus, Rueggeberg, Frederick A., Soto-Montero, Jorge R., André, Carolina B., Resende, Bruna A., Giannini, Marcelo, Cavalli, Vanessa
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01-05-2022; Springer Nature B.V
• Subjects: Animals; Cattle; Cigarette smoke; Color; Dental Enamel; Dentin; Dentistry; Enamel; Hydrogen Peroxide; Light; Medicine; Original Article; Tea; Tooth Bleaching; Tooth Bleaching Agents - pharmacology; Tooth bleaching; Staining; Dental enamel; Irradiance; Violet LED light
• ISSN: 1436-3771; 1432-6981; 1436-3771
• DOI: 10.1007/s00784-021-04357-x

 
Objectives
This study characterized a violet LED light (V-LED; bright max whitening) tooth whitening device and evaluated its efficacy on stained enamel compared to hydrogen peroxide (HP).
Materials and methods
Characterization of the V-LED beam profile was performed using a laser beam-profiler. The irradiance was measured throughout an exposure cycle at 0- and 8-mm distances using an integrating sphere and a spectral radiometer. Bovine enamel/dentin blocks stained with black tea (BT), cigarette smoke (CS), or without staining (CONT) were subjected to V-LED or 40% HP (
n
 = 10/group). Color parameters (ΔL, Δa, Δb, and ΔE
00
) were measured using a digital spectrophotometer. Light transmission was estimated through 1-mm-thick bovine enamel slices (
n
 = 5). ΔL, Δb, ΔE
00
, and irradiance were analyzed by two-way ANOVAs and Tukey’s tests, Δa by Kruskal–Wallis and Mann–Whitney tests, and light transmission by
t
-test (
α
 = 5%).
Results
Heterogeneous beam distribution was observed for the emitting V-LED chips. After 20 sequential exposures, irradiance levels were reduced 25–50%, regardless of the distance from V-LED. Localized irradiance values were statistically different between beam locations and different distances from the target. V-LED produced lower ΔE
00,
ΔL, Δa, and Δb values than HP for CONT and BT, with no differences for CS. Light transmittance decreased approximately 98% through 1-mm thick enamel.
Conclusions
V-LED irradiance was heterogeneous and decreased throughout the exposure cycles and was also greatly reduced with increasing tip distance. V-LED produced a significantly lower whitening effect on BT and control teeth.
Clinical relevance
This study contributes to the knowledge of V-LED and its clinical use.