Fracture and shear bond strength analyses of different dental veneering ceramics to zirconia

• Autor(a) principal: Diniz, Alexandre C.
• Data de Publicação: 2014
• Outros Autores: Nascimento, Rubens Maribondo do, Souza, Júlio César Matias, Henriques, Bruno B., Carreiro, Adriana da Fonte Porto
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UFRN
• Texto Completo: https://repositorio.ufrn.br/jspui/handle/123456789/28597
• topic: Dental porcelain; Zirconia; Shear test; Metal-free; Fracture

The purpose of this work was to evaluate the interaction of different layering porcelains with zirconia via shearbond strength test and microscopy. Four different groups of dental veneering porcelains (VM9, Zirkonzanh,Ceramco, IPS) were fused onto forty zirconia-based cylindrical substrates (8 mm in diameter and 12 mm inheight) (n= 10), according to the manufacturer's recommendations. Additionally, layered dental porcelain(D-sign, Ivoclar) wasfired on ten Ni–Cr cylindrical substrates Shear bond strength tests of the veneering porce-lain to zirconia or Ni–Cr were carried out at a crosshead speed of 0.5 mm/min. After the shear bond tests, the in-terfaces were analyzed by scanning electron microscopy (SEM). The fracture type exhibited by the differentsystems was also assessed. The results were statistically analyzed by ANOVA at a significant level ofpb.05.The shear bond strength values of the porcelain-to-NiCr interfaces (25.3 ± 7.1 MPa) were significantly higherthan those recorded for the following porcelain-to-zirconia systems: Zirkonzanh (18.8 ± 1 MPa), Ceramco(18.2 ± 4.7 MPa), and IPS (16 ± 4.5 MPa). However, no significant differences were found in the shear bondstrength values between the porcelain-to-NiCr and porcelain (VM9)-to-zirconia (23.2 ± 5.1 MPa) groups(pN.05). All-ceramic interfaces revealed mixed failure type, cohesive in the porcelain and adhesive atthe interface.This study demonstrated that all-ceramic systems do not attain yet the same bond strength standards equivalentto metal–ceramic systems. Therefore, despite the esthetic appeal of all-ceramic restorations, the adhesionbetween the porcelain and zirconia framework is still an issue considering the long term success of therestoration.