Effect of violet LED light on in-office bleaching protocols: a randomized controlled clinical trial

• Published in: Journal of applied oral science Vol. 28; p. e20190720
• Main Authors: KURY, Matheus, WADA, Erica Eiko, SILVA, Daylana Pacheco da, TABCHOURY, Cínthia Pereira Machado, GIANNINI, Marcelo, CAVALLI, Vanessa
• Format: Journal Article
• Language: English
• Published: Brazil Faculdade De Odontologia De Bauru - USP 01.01.2020; University of São Paulo
• Subjects: Adolescent; Adult; Analysis of Variance; carbamide peroxide; Carbamide Peroxide - administration & dosage; Colorimetry; Combined Modality Therapy; Dental Enamel - drug effects; Dental Enamel - radiation effects; dentin sensitivity; Dentin Sensitivity - chemically induced; DENTISTRY, ORAL SURGERY & MEDICINE; Female; Humans; hydrogen peroxide; Hydrogen Peroxide - administration & dosage; Light; Male; Original; Phototherapy - methods; Reference Values; Risk Factors; Spectrophotometry; Statistics, Nonparametric; Surface Properties - drug effects; Surface Properties - radiation effects; tooth bleaching; Tooth Bleaching - methods; Tooth Bleaching Agents - administration & dosage; Treatment Outcome; Young Adult; Carbamide Peroxide; Hydrogen Peroxide; Light; Tooth Bleaching; Dentin Sensitivity
• ISSN: 1678-7757; 1678-7765; 1678-7765
• DOI: 10.1590/1678-7757-2019-0720

Objective This study evaluated the clinical effect of violet LED light on in-office bleaching used alone or combined with 37% carbamide peroxide (CP) or 35% hydrogen peroxide (HP). Methodology A total of 100 patients were divided into five groups (n=20): LED, LED/CP, CP, LED/HP and HP. Colorimetric evaluation was performed using a spectrophotometer (ΔE, ΔL, Δa, Δb) and a visual shade guide (ΔSGU). Calcium (Ca)/phosphorous (P) ratio was quantified in the enamel microbiopsies. Measurements were performed at baseline (T 0 ), after bleaching (T B ) and in the 14-day follow-up (T 14 ). At each bleaching session, a visual scale determined the absolute risk (AR) and intensity of tooth sensitivity (TS). Data were evaluated by one-way (ΔE, Δa, ΔL, Δb), two-way repeated measures ANOVA (Ca/P ratio), and Tukey post-hoc tests. ΔSGU and TS were evaluated by Kruskal-Wallis and Mann-Whitney, and AR by Chi-Squared tests (a=5%). Results LED produced the lowest ΔE (p<0.05), but LED/HP promoted greater ΔE, ΔSGU and Δb (T 14 ) than HP (p<0.05). No differences were observed in ΔE and ΔSGU for LED/CP and HP groups (p>0.05). ΔL and Δa were not influenced by LED activation. After bleaching, LED/CP exhibited greater Δb than CP (p>0.05), but no differences were found between these groups at T 14 (p>0.05). LED treatment promoted the lowest risk of TS (16%), while HP promoted the highest (94.4%) (p<0.05). No statistical differences of risk of TS were found for CP (44%), LED/CP (61%) and LED/HP (88%) groups (p>0.05). No differences were found in enamel Ca/P ratio among treatments, regardless of evaluation times. Conclusions Violet LED alone produced the lowest bleaching effect, but enhanced HP bleaching results. Patients treated with LED/CP reached the same efficacy of HP, with reduced risk and intensity of tooth sensitivity and none of the bleaching protocols adversely affected enamel mineral content.