Effects of Ultramorphological Changes on Adhesion to Lased Dentin-Scanning Electron Microscopy and Transmission Electron Microscopy Analysis

Autor(es)

Moretto, Simone G. ^[1] ; Azambuja, Jr., Nilton ^[1] ; Arana-Chavez, Victor E. ^[2] ; Reis, Andre F. ^[3] ; Giannini, Marcelo ^[4] ; Eduardo, Carlos de P. ^[1] ; De Freitas, Patricia M. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Dept Dent, Fac Odontol, Lab Especial Laser Odontol, BR-05508000 Sao Paulo - Brazil

^[2] Univ Sao Paulo, Div Oral Biol, Dept Mat Dent, BR-05508000 Sao Paulo - Brazil

^[3] Univ Guarulhos, Fac Odontol, Dept Dent, BR-07023070 Guarulhos, SP - Brazil

^[4] Univ Estadual Campinas, Fac Odontol Piracicaba, Dept Dent, BR-13414903 Piracicaba, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: MICROSCOPY RESEARCH AND TECHNIQUE; v. 74, n. 8, p. 720-726, AUG 2011.
• Citações Web of Science: 25

Resumo

Dentin irradiation with erbium lasers has been reported to alter the composite resin bond to this treated surface. There is still a lack of studies reporting the effect of erbium lasers on dentin organic content and elucidating how laser treatment could interfere in the quality of the resin-dentin interface. This study aimed to evaluate the effect of erbium laser irradiation on dentin morphology and microtensile bond strength (lTBS) of an adhesive to dentin. Seventy-two dentin disks were divided into nine groups (n = 8): G1-Control (600-grit SiC paper); Er:YAG groups: G2-250 mJ/4 Hz; G3-200 mJ/4 Hz; G4-180 mJ/10 Hz; G5-160 mJ/10 Hz; Er, Cr:YSGG groups: G6-2 W/20 Hz; G7-2.5 W/20 Hz; G8-3 W/20 Hz; G9-4 W/20 Hz. Specimens were processed for cross-sectional analysis by scanning electron microscopy (SEM) (n = 3), transmission electron microscopy (TEM) (n = 2), and adhesive interface (n = 3). Forty-five dentin samples (n = 5) were restored and submitted to lTBS testing. ANOVA (alpha = 5%) revealed that G1 presented the highest lTBS values and irradiated groups did not differ from each other. TEM micrographs showed a superficial layer of denatured collagen fibrils. For SEM micrographs, it was possible to verify the laser effects extending to dentin subsurface presenting a rough aspect. Cross-sectional dentin micrographs of this hybridized surface revealed a pattern of modified tags with ringlike structures around it. This in vitro study showed that erbium laser irradiation interacts with the dental hard tissue resulting in a specific morphological pattern of dentin and collagen fibrils that negatively affected the bond strength to composite resin. Microsc. Res. Tech. 74:720-726, 2011. (C) 2010 Wiley-Liss, Inc. (AU)

• Processo FAPESP: 07/06083-4 - Análise da resistência de união, nanoinfiltração e características ultramorfológicas das interfaces de união resina-dentina produzidas por cimentos auto-adesivos ao longo do tempo
• Beneficiário: André Figueiredo Reis
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 05/60697-9 - Avaliacao dos efeitos da irradiacao do substrato dentinario com laser er:yag nos procedimentos restauradores adesivos: analise de permeabilidade, das propriedades fisicas e observacao microscopica.
• Beneficiário: Marcelo Giannini
• Modalidade de apoio: Auxílio à Pesquisa - Regular