Affiliation:
1. Department of Restorative Dentistry Piracicaba Dental School, University of Campinas Piracicaba São Paulo Brazil
2. Department of Dental Materials and Prosthodontics School of Dentistry, São Paulo State University (UNESP) Araraquara Brazil
3. Vitreous Materials Laboratory (LaMaV), Department of Materials Engineering Federal University of São Carlos São Carlos Brazil
4. Dental Research Division School of Dentistry, Paulista University (UNIP) São Paulo Brazil
5. Department of Physiology and Pathology School of Dentistry, São Paulo State University (UNESP) Araraquara Brazil
Abstract
AbstractAimThis study evaluated the efficacy and cytotoxicity of 35% hydrogen peroxide (HP) gel incorporated with 10% (w/w) biosilicate (BioS) on sound enamel and early‐stage enamel erosion lesions.MethodsDiscs of enamel/dentin were selected, subjected to erosive cycles (0.3% citric acid, pH 2.6), and treated with (n = 8): HP (35% HP, positive control); HP_BioS [carboxymethyl cellulose (CMC) + HP + BioS]; BioS (CMC + BioS); CMC (negative control). The discs were adapted to artificial pulp chambers with the enamel exposed for bleaching, and the dentin facing toward the culture medium (Dulbecco's modified Eagle's medium [DMEM]). Bleaching was performed in three 30‐min sessions at 7‐day intervals. After bleaching, the diffusion product (DMEM extract + diffused HP) was pipetted onto MDPC‐23 odontoblastic cell line and inoculated. Color parameters (ΔL, Δa, Δb), color change (ΔE00), and changes in whiteness index (ΔWID) were determined before (T0) and after the last bleaching session (T3). Cell viability (MTT, %), H2O2 diffusion (μg/mL), oxidative cell stress (OxS), and cell fluorescence (live/dead assay, in confocal microscopy) were assessed (ANOVA/Tukey; α = 0.05).ResultsNo difference in ΔL, Δa, Δb, ΔE00, and ΔWID were found between HP and HP_BioS (p > 0.05). The incorporation of BioS decreased the HP diffusion into the substrates and mitigated oxidative stress in early‐stage eroded enamel (p < 0.05). HP_BioS presented significantly higher cell viability compared with HP under erosion conditions. Live/dead assay indicated that BioS_HP maintained viability with larger clusters of viable cells.ConclusionIncorporating BioS into HP maintained bleaching effectiveness, favored cell viability, reduced the oxidative stress, and the cytotoxicity in teeth with early‐stage erosion.Clinical SignificanceBioS formulation showed promising results for reducing cytotoxicity in patients seeking tooth bleaching and presenting undetectable early‐stage erosion.
Funder
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Conselho Nacional de Desenvolvimento Científico e Tecnológico
Fundação de Amparo à Pesquisa do Estado de São Paulo