In vitro evaluation of the efficacy of self-applied LED light units used in the dental bleaching

• Grant number: 23/09436-8
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date until: September 01, 2023
• End date until: February 29, 2024
• Field of knowledge: Health Sciences - Dentistry - Dental Clinics
• Principal Investigator: Vanessa Cavalli Gobbo
• Grantee: Amanda Ferreira Felix
• Host Institution: Faculdade de Odontologia de Piracicaba (FOP). Universidade Estadual de Campinas (UNICAMP). Piracicaba , SP, Brazil

Abstract

The increasing demand for whiter teeth has stimulated the self-application of LED light devices, which would promote fast whitening results when associated with low-concentrated hydrogen peroxide (HP). However, there are no reports on the safety and possible adverse effects, given that some devices present near-UVA wavelengths. In this regard, this study will evaluate the efficacy and safety of self-applied LED light devices combined with 6% HP and compare them to light-curing devices. Bovine enamel discs will be flattened, polished, stained with black tea, and submitted to 6% HP combined with (n=10): 1) self-applied LED light (Venus Stars - USA White), 2) self-applied violet LED light (Ivismile 4, Ivismile), 3) violet LED light (Bright Maxx, MMOptics), 4) blue LED light (Radii Cal, SDI); 5) polywave light (Valo Grand, Ultradent). The control groups consist of 6% HP and 35% HP, both without light. The whitening protocol adopted for the self-applied light sources + HP will follow the manufacturer's instructions for at-home treatment while the others will be treated according to the in-office whitening technique. Color change (E00) and whitening index (WID) will be determined at baseline (T0), 24 hours after whitening (T1), and 14 days after whitening (T2). The temperature variation (°C) will be measured on the enamel surface before and after irradiation, and the cytotoxicity of gingival fibroblasts will be determined after the whitening protocols. Data obtained will be subjected to statistical tests according to data normality and homoscedasticity (± = 5%).