Influence of ceramic thickness and light-curing time on the long-term µTBS of silica-based ceramic to human dentin

• Autor(a) principal: Barca, Diana Capelli [UNESP]
• Data de Publicação: 2017
• Outros Autores: Moura, Dayanne Monielle Duarte, da Costa, Giovanna de Fátima Alves, Pavanelli, Carlos Augusto [UNESP], Bottino, Marco Antonio [UNESP], Souza, Rodrigo Othávio Assunção
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://dx.doi.org/10.1080/01694243.2016.1274134; http://hdl.handle.net/11449/178547
• topic: ceramic; dentin; light-curing; micro-tensile; Resin cements

To evaluate the influence of ceramic thickness, light-curing time and thermal cycling (TC) on the μTBS of a glass ceramic cemented to human dentin. Ninety-six human molars were embedded in acrylic resin and the occlusal surface was sectioned to exposure dentin. Blocks of feldspathic ceramic (Vita PM9) with different thickness (6 × 6 × 1 mm/2 mm/3 mm) were fabricated with wax pattern and sprue. The blocks and teeth were randomly distributed into 12 groups (n = 8) according to the ceramic thickness (V1: 1 mm, V2: 2 mm and V3: 3 mm), light-curing time (40s; 80s), and TC (yes; no). Dentin was etched, washed and dried. The adhesive (Excite, Ivoclar) was applied onto the dentin surface and light-cured (20s), and the ceramic surface was etched with 10% HF, washed, dried and silanized. The ceramic blocks were cemented to dentin (Variolink II, Ivoclar). The assembly ceramic/dentin was stored in distilled water (37 °C; 24 h) and sectioned in X and Y axes to get the sticks. Half of the samples were submitted to TC while the other half underwent micro-tensile bond testing. The data (MPa) were analyzed by 3-way ANOVA and Tukey test (5%). ANOVA revealed significant interaction among the factors (p = 0.0001). Tukey test showed significant higher bond strength for the 2 mm group (V280s = 17.0 ± 9.1 MPa) in comparison to the other groups. V340s TC (2.7 ± 6.3 MPa) presented lower bond strength, which was similar to the groups V180s TC (4.6 ± 4.9 MPa) and V240s TC (5.9 ± 4.4 MPa). Light-curing for 80s promoted significant higher bond strength of thicker ceramic (3 mm) than light-curing for 40s.