Aim:This study aims to evaluate the microshear bond strength of zirconia-based ceramics with different resin cement systems and surface treatments.Materials and Methods:Forty blocks of zirconia-based ceramic were prepared and embedded in polyvinyl chloride (PVC) tubes with acrylic resin. After polishing, the samples were washed in an ultrasonic bath and dried in an oven for 10 min. Half of the samples were subjected to sandblasting with aluminum oxide. Blocks were divided into four groups (n = 10) in which two resin cements were used as follows: (1) RelyX™ U100 with surface-polished zirconia; (2) RelyX™ U100 with surface-blasted zirconia; (3) Multilink with surface-polished zirconia; and 4) Multilink with surface-blasted zirconia. After performing these surface treatments, translucent tubes (n = 30 per group) were placed on the zirconia specimens, and resin cement was injected into them and light cured. The PVC tubes were adapted in a universal testing machine; a stiletto blade, which was bolted to the machine, was positioned on the cementation interface. The microshear test was performed at a speed of 0.5 mm/min. Failure mode was analyzed in an optical microscope and classified as adhesive, cohesive, or mixed.Results:The null hypothesis of this study was rejected because there was a difference found between the resin cement and the surface treatment. There was a statistical difference (P < 0.005) in RelyX™ U100 with surface-blasted zirconia, in relation to the other three groups. For Multilink groups, there was no statistical difference between them.Conclusion:Self-adhesive resin cement showed a more significant tendency toward bond strength in the ceramic-based zirconium oxide grit-blasted surfaces.

Dentes anteriores escurecidos comprometem a estética do sorriso; por isso, reabilitá- los, estética e funcionalmente, tornou-se um dos maiores desafios clínicos para o cirurgião-dentista. O desenvolvimento da Odontologia Adesiva, associado à capacidade de condicionamento das cerâmicas odontológicas, garantindo a alta qualidade na união desses materiais aos tecidos dentais, fez com que o tratamento com laminados cerâmicos apresente altas taxas de satisfação, não só pela característica óptica natural alcançada inicialmente, mas, principalmente, por o efeito obtido manter-se ao longo dos anos. O presente trabalho tem como objetivo comparar o resultado estético de dois tipos de facetas, com cerâmicas vítreas diferentes, por meio do relato de um caso clínico de reabilitação do dente 21 escurecido por traumatismo.

This report describes the restoration of an anterior fractured tooth with a fiberglass CAD-CAM post-and-core followed by rapid orthodontic extrusion. The post space was prepared, the post-and-core was luted and a interim crown was luted to allow the tooth extrusion through the use of orthodontic buttons and elastic rubber bands. A lithium disilicate glass-ceramic crown was luted and the case was followed up after 6 and 12 months.