Influence of different but compatible all-ceramic materials and bonding systems on dentin bonding properties

This study aimed to investigate the effects of various compatible all-ceramic materials and bonding systems, on the bonding properties of dentin. Five types of commonly used all-ceramic materials (Cerec Blocs, IPS e. max Press, IPS e. max ZirCAD, Incoris Alumina, In-Ceram Alumina) were bonded with three types of adhesives (Multilink N, Variolink N, Relyx Unicem) for nuclear porcelain tile preparation. We evaluated the polymerization conversion rates, shear bonding strength (SBS), and micro-tensile bond strength (TBS) for each combination. The polymerization conversion rates, SBS and TBS differed significantly for all 3 adhesives with each all-ceramic group ( P < 0.05). The Relyx Unicem agent had higher adhesive properties compared with the Variolink N and Multilink N agents ( P < 0.05). The polymerization conversion rate, SBS and TBS of the five all-ceramic materials differed significantly with each adhesive ( P < 0.05). The Cerec Blocs had the highest adhesive performance ( P < 0.05). The polymerization conversion rate of adhesives differed with each all-ceramic material, while the dentin bonding strength differed with each all-ceramic material and adhesive. Clinically, all-ceramic materials with a high transparency and low refraction are recommended. For opaque all-ceramic restorations, the curing light time and polymerization reaction rate should be increased to improve the dentin bonding performance.