The number of specimens in a furnace affects the biaxial flexural strength of veneered zirconia specimens after sintering

• Published in: Journal of adhesion science and technology 2021-03, Vol.35 (6), p.663-672
• Main Authors: Rippe, Marília Pivetta, de Melo, Renata Marques, Moura, Dayanne Monielle Duarte, Machado, Pablo Soares, Souza, Rodrigo Othávio Assunção, Valandro, Luiz Felipe, Bottino, Marco Antonio, Özcan, Mutlu
• Format: Article
• Language: English
• Subjects: bilayer; Cubes; dental ceramics; Flexing; Flexural strength; heat distribution; Porcelain; Porcelain firing; Sintering; Tetragonal zirconia polycrystals; Yttria-stabilized zirconia; zirconia; Zirconium dioxide
• ISSN: 0169-4243; 1568-5616
• DOI: 10.1080/01694243.2020.1816790

This study evaluated the effect of the number of specimens in a furnace during the firing of porcelain-zirconia (Y-TZP) discs on their biaxial flexural strength. Eighty bilayer disc-shaped specimens (∅: 15mm; thickness: 1.2 mm, ISO 6872) of zirconia (Vita In-Ceram YZ Cubes/Vita) and porcelain (Vita VM9) ceramics, were prepared and divided into four groups (n = 20) according to the number of specimens in a furnace for each porcelain sintering: G1- one disc/20 sintering cycles.; G2 - two discs/10 sintering cycles.; G5-five discs/4 sintering cycles; and G10 - ten discs/2 sintering cycles. Then, the specimens were submitted to biaxial flexure testing (BFS) (1 mm/min, water). The data (MPa) were analyzed with Kruskal-Wallis test followed by the Dunn's post hoc analysis at a 95% level of confidence (α = 0.05). Kruskal-Wallis showed that the number of samples in the furnace affected flexural strength (p