Changes in the stiffness of demineralized dentin following application of tooth whitening agents

Autor(es)

Berger, Sandrine Bittencourt ^[1] ; Pavan, Sabrina ^[2] ; Pimenta Vidal, Cristina de Mattos ; Dos Santos, Paulo Henrique ^[3] ; Giannini, Marcelo ^[4] ; Bedran-Russo, Ana Karina ^[2]

Afiliação do(s) autor(es)

^[1] Univ Norte Parana, Sch Dent, Dept Restorat Dent, Londrina, PR - Brazil

^[2] Univ Chicago, Coll Dent, Dept Restorat Dent, Chicago, IL 60637 - USA

^[3] Sao Paulo State Univ, Aracatuba Dent Sch, Dept Dent Mat & Prosthodont, Aracatuba, SP - Brazil

^[4] Univ Estadual Campinas, Piracicaba Dent School, Operat Dent Div, Dept Restorat Dent, BR-13414903 Piracicaba, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: ACTA ODONTOLOGICA SCANDINAVICA; v. 70, n. 1, p. 56-60, JAN 2012.
• Citações Web of Science: 9

Resumo

Objective. The purpose of this study was to evaluate the effect of the bleaching agents on the elastic modulus of bovine demineralized dentin matrix (EMDM). Materials and methods. Eighty-five slices were obtained from 17 bovine teeth. The slices were divided randomly into five experimental groups (n = 17): unbleached control group (CG), 4% hydrogen peroxide (HP4), 4% hydrogen peroxide + 0.05% Ca (HP4 + Ca), 7.5% hydrogen peroxide + ACP (HP7.5) and 10% carbamide peroxide (CP10). The HP4, HP4 + Ca and CP10 groups were treated with the bleaching agents for 8 h/day (14 days), while the samples of HP7.5 group were exposed to bleaching agent for 30 min twice a day (14 days). The CGwas kept in 100% humidity. After bleaching treatments, the enamel of the samples was removed and 85 dentin beams (0.5 x 1.7 x 7.0 mm) were prepared. Afterwards, the beams were immersed in 10% phosphoric acid solution (5 h) and rinsed with water (10 min). The beams were tested after 24 h, 7 and 14 days of storage in distilled water, using three-point bend method. Data were statistically analyzed using ANOVA and Fisher's test. Results. All bleaching treatments reduced the EMDM. After 14 days post-bleaching, the EMDM increased for HP4 and HP4+Ca groups. Conclusions. The use of bleaching agents promoted a decrease in EMDM, which indicates that the bleaching treatment interacts with the dentin organic matrix. The EMDM measurement for the specimens of the 7.5% hydrogen peroxide group that were immersed in water at 14 days post-bleaching did not recover the EMDM values when compared to the control group. (AU)

• Processo FAPESP: 07/54784-1 - Efeitos de diferentes concentrações do peróxido de hidrogênio nas estruturas dentárias
• Beneficiário: Sandrine Bittencourt Berger
• Linha de fomento: Bolsas no Brasil - Doutorado
• Processo FAPESP: 05/60696-2 - Efeitos de agentes clareadores de alta concentração para tratamento em consultório na microdureza, morfologia e composição química do esmalte humano
• Beneficiário: Marcelo Giannini
• Linha de fomento: Auxílio à Pesquisa - Regular