Effect of resin cement space on the fatigue behavior of bonded CAD/CAM leucite ceramic crowns

• Autor(a) principal: Venturini, Andressa Borin
• Data de Publicação: 2020
• Outros Autores: Wandscher, Vinícius Felipe, Marchionatti, Ana Maria Estivalete, Evangelisti, Edoardo, Ramos, Gabriela Freitas [UNESP], Melo, Renata Marques [UNESP], May, Liliana Gressler, Baldissara, Paolo, Valandro, Luiz Felipe
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://dx.doi.org/10.1016/j.jmbbm.2020.103893; http://hdl.handle.net/11449/199022
• topic: Cement thickness; Fatigue test; IPS Empress CAD; Radial crack; Survival probability

This study evaluated the influence of occlusal resin cement space on the fatigue performance of bonded-leucite crowns to a dentin-analogue material. Leucite anatomical crowns were adhesively cemented to dentin-like preparations having distinct occlusal cement space (50, 100 and 300 μm) (n = 18), and subjected to step-stress fatigue testing (150 N – 350 N; step-size: 25 N; 20,000 cycles/step; 20 Hz). Fatigue data (load and number of cycles for failure) were analyzed using Kaplan–Meier and Mantel–Cox (log-rank) tests (p <0.05). Fractographic analysis and occlusal internal space measurements were also performed. There was no significant difference for the distinct occlusal cement layer (50 μm: 289 N, 136,111 cycles; 100 μm: 285 N, 132,778 cycles; 300 μm: 246 N, 101,667 cycles). Occlusal internal space analysis showed a mean thickness of 120.4 (50 μm), 174.9 (100 μm) and 337.2 (300 μm). All failures were radial cracks originating at the ceramic-cement interface. Distinct occlusal cement spaces had no effect on the fatigue behavior of anatomical leucite crowns.