ABSTRACT
The aim of this study was to evaluate the fluorination of a zirconia surface as an alternative treatment for bonding to resin cement; the null hypothesis was that fluorination would not improve adhesion values. Four different surface treatments were performed on the surface of yttria-stabilized tetragonal zirconia polycrystal discs (N = 80): Ctrl (control), no treatment; SB, sandblasting with 50-µm alumina particles; SBS, sandblasting with 30-µm silica-modified alumina particles and application of silane; and SF, fluorination with sulfur hexafluoride-containing plasma. The surface roughness (Ra) of each group was measured after surface treatment. Dual-cure resin cement was inserted into cylindrical matrices, and 2 cylinders (0.7 × 3.0 mm) were cemented to each ceramic disc surface. Half of the specimens were thermocycled, and microshear bond strength tests were performed. The SBS group presented the highest median values of surface roughness, while the Ctrl group presented the lowest values. Without thermocycling, the median bond strength of the SF group was statistically similar to those of the sandblasted groups (SB and SBS). After thermocycling, all specimens from the Ctrl and SF groups presented as failures, and their bond strength was considered null. The SB and SBS groups presented decreased bond strengths. Failures were classified as predominantly mixed at the adhesive interface. The fluorination of the zirconia ceramic surface with sulfur hexafluoride as a source gas did not promote stable bond strengths to resin cement. After aging, adhesion was possible only after sandblasting of the ceramic surface.
Subject(s)
Dental Bonding , Resin Cements/chemistry , Sulfur Hexafluoride/chemistry , Zirconium/chemistry , Aluminum Oxide/chemistry , Ceramics/chemistry , Dental Materials/chemistry , Dental Stress Analysis , Halogenation , Materials Testing , Shear Strength , Silanes/chemistry , Surface Properties , Yttrium/chemistryABSTRACT
As próteses livres de metal têm sido muito utilizadas na odontologia restauradora. Diferentes sistemas cerâmicos surgiram nos últimos anos com tecnologia de fabricação apurada e excelente qualidade estética. As cerâmicas reforçadas por óxido de zircônia têm sido indicadas na confecção de coroas totais e próteses fixas em dentes anteriores e posteriores. Em função da necessidade de se realizar uma cimentação adesiva eficiente, este trabalho tem por objetivo realizar uma revisão da literatura dos métodos de tratamento de superfície empregados para as cerâmicas reforçadas por óxido de zircônia previamente à cimentação adesiva...
Metal-free prostheses are extensively used in Restorative Dentistry. Different ceramic systems appeared in the last few years with accurate manufacturing technology and high aesthetic quality. Zirconium oxide-reinforced ceramics have been recommended for fabrication of fixed prostheses and full crowns, both for anterior and posterior teeth. The aim of this literature review was to address relevant aspects to achieve effective adhesive cementation of different surface treatment methods of zirconium-oxide reinforced ceramics, before adhesive cementation...
