The Influence of Silane on the Interfacial Fracture Toughness of PICNs with Resin Cement

CAD-CAM composites can be divided into 2 sub-classes according to their microstructure, Polymer Infiltrated Ceramic Networks (PICN) and Dispersed Filler (DF) materials1. Pre-treatment procedures including creation of micro-roughness using hydrofluoric acid (HF) for micro-mechanical retention and silanization for chemical bonding are commonly reported to be necessary to bond PICNs to the resin cement. On the other hand, PICNs were shown to exhibit a retentive polymer-based honeycomb structure when etched, which promotes the micro-mechanical bond but could reduce the need of silane since the inorganic part of the material surface is removed by the etching procedure. The objective of this study was to evaluate the influence of silane on Interfacial Fracture Toughness (IFT) at mouth temperature of composite cement with PICN versus DF materials, after HF etching and upon thermocycling aging. The hypothesis was that silane pre-treatment has no effect on the IFT of composite cement with PICNs.