Influence of Tooth Pigmentation on H2O2 Diffusion and Its Cytotoxicity After In-office Tooth Bleaching

Autor(es)

de Oliveira Duque, C. C. ^[1] ; Soares, D. G. ^[2] ; Briso, A. L. F. ^[3] ; Ortecho-Zuta, U. ^[1] ; de Oliveira Ribeiro, R. A. ^[1] ; Hebling, J. ^[4] ; de Souza Costa, C. A. ^[5]

Afiliação do(s) autor(es)

^[1] Univ Estadual Paulista UNESP, Araraquara Sch Dent, Dept Dent Mat & Prosthodont, Araraquara, SP - Brazil

^[2] Univ Sao Paulo, Bauru Sch Dent, Dept Operat Dent Endodont & Dent Mat, Bauru, SP - Brazil

^[3] Univ Estadual Paulista UNESP, Aracatuba Sch Dent, Dept Restorat Dent, Aracatuba, SP - Brazil

^[4] Univ Estadual Paulista UNESP, Dept Orthodont & Pediat Dent, Araraquara Sch Dent, Araraquara, SP - Brazil

^[5] Univ Estadual Paulista UNESP, Araraquara Sch Dent, Dept Physiol & Pathol, Araraquara, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Operative Dentistry; v. 45, n. 6, p. 632-642, NOV-DEC 2020.
• Citações Web of Science: 0

Resumo

Objective: The aim of this study was to evaluate the influence of the presence of pigments in tooth structures on the trans-enamel and trans-dentin diffusion of hydrogen peroxide (H2O2) and its cytotoxicity after carrying out an in-office bleaching therapy. Methods and Materials: A bleaching gel with 35% H2O2 was applied for 45 minutes (three times for 15 minutes) on enamel and dentin discs (n=6), either previously submitted to the intrinsic pigmentation protocol with a concentrated solution of black tea, or not, defining the following groups: G1, unbleached untreated discs (control 1); G2, unbleached pigmented discs (control 2); G3, bleached untreated discs; G4, bleached pigmented discs. The discs were adapted to artificial pulp chambers, which were placed in wells of 24-well plates containing 1 mL culture medium (Dulbecco's modified Eagle's medium {[}DMEM]). After applying the bleaching gel on enamel, the extracts (DMEM + components of bleaching gel that diffused through the discs) were collected and then applied on the cultured MDPC-23 odontoblast-like cells. Cell viability (methyl tetrazolium assay and Live \& Dead, Calcein AM, and ethidium homodimer-1 {[}EthD-1] probes), the amount of H2O2 that diffused through enamel and dentin (leuco-crystal violet product), and the H2O2-mediated oxidative cell stress (SOx) and components of degradation were assessed (analysis of variance/Tukey; alpha=0.05). Results: There was no significant difference between the groups G1 and G2 for all the parameters tested (p>0.05). Reduction in the trans-enamel and trans-dentin diffusion of H2O2 occurred for G4 in comparison with G3. Significantly lower cell viability associated with greater oxidative stress was observed for G3 (p<0.05). Therefore, in-office tooth bleaching therapy performed in pigmented samples caused lower cytotoxic effects compared with untreated samples submitted to the same esthetic procedure (p<0.05). Conclusion: According to the methodology used in this investigation, the authors concluded that the presence of pigments in hard tooth structures decreases the trans-enamel and trans-dentin diffusion of H2O2 and the toxicity to pulp cells of an in-office bleaching gel with 35% H2O2. (AU)

• Processo FAPESP: 15/21770-4 - Desenvolvimento de produtos clareadores dentais experimentais baseados em princípios dos processos oxidativos avançados: análise dos efeitos estéticos e biológicos
• Beneficiário: Carlos Alberto de Souza Costa
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 16/10928-9 - Desenvolvimento e análise de produtos clareadores inovadores utilizando uma peroxidase-hêmica como agente catalizador
• Beneficiário: Carla Caroline de Oliveira Duque
• Modalidade de apoio: Bolsas no Brasil - Doutorado