Evaluation of the Effect of Various Cementation Protocols Used for 10% Zirconia-Reinforced Lithium Glass Ceramic Veneer on Shear Bond Strength to Resin Cement (An In Vitro Study)

Abstract

Bonding failure between ceramic restoration and cement dramatically influences the success of resin-bonded ceramic restoration. This study evaluates the influence of various fitting surface treatments of 10% zirconia-reinforced lithium glass ceramic (ZLS) on its shear bonding strength to resin cement. Sixty blocks sized 8 × 8 × 2 mm3 were cut from a ZLS. All specimens were fired for 10 min and separated into six groups according to surface treatment: GI (Without treatment), GII (10% HF acid, Ultra Sound water bath US, and silane coupling agent S), GIII (HF, US, S, and bonding without light cure B1), GIV (HF, US, 37% phosphoric acid PA, US, S, B1), GV (HF, US, S, and bonding with light curing B2), VI (HF, US, PA, US, S, and B2). The treated specimens were cemented to a resin cement cylinder of 3.5 mm in diameter and 2 mm in height (Variolink, Esthetic. Neutral). A universal test machine was used to test the shear bond strength (SBS) and SEM for failure mode. The result indicated that applying a bonding agent on the prepared surface of ZLS without curing before cementation significantly increases the shear bond strength and affects the failure mode. In contrast, the application of PA does not influence bond strength.