Surface Conditioning Protocol for the Adhesion of Resin-based Materials to Glassy Matrix Ceramics: How to Condition and Why?

Question: What is the best surface conditioning protocol for durable adhesion of resin-based materials to glassy matrix ceramics? Answer: Glassy matrix ceramics, also known as silicabased ceramics, are typically reinforced with feldspar, leucite, fluormica glass or lithium disilicate. Glass ceramics are acid sensitive when etched with hydrofluoric acid gel and they respond well to adhesive bonding techniques where silanization and adhesive resin applications are performed. In such ceramics, more pronounced surface roughness can be obtained with the increase in the amount of glassy phase present in the microstructure, which can improve the potential adhesion of resin-based luting cements to these ceramics. Proper conditioning of glass ceramics together with the subsequent application of the adhesive procedures not only enables fabrication of minimally invasive restorations, but also reinforces the vitreous matrix, increasing its strength after adhesive cemention. Since the type of ceramic matrix, etching method, silanization, and adhesive resin application are important parameters in durable adhesion to glass ceramics, the surface conditioning sequence presented in the Table (below) is recommended.