Effect of Different Surface Treatments on Bond Strength of Resin Cement with Lithium Silicate Ceramics

Abstract

Objective: This study was designed to evaluate different surface treatments affecting bond strength of different lithium silicate ceramics, due to long-term survival of adhesive esthetic restorations greatly depends on achieving maximum adhesive bonding strength, however one of the most common failures is loss of retention &de-bonding of ceramic restorations. Materials and methods: Total number of 42 lithium silicate squared samples were fabricated with a dimension of 1 cm 2 , categorized as two groups (N=21) according to the two different materials. (Obsidian and Vita Suprinity). Every group of them receives three different types of surface treatments: acid etch, sand blasting and laser then all samples were bonded using a resin cement (RC) to a composite substrate. After that, all samples were subjected to thermocycling. Shear bond strength was assessed using a universal test machine while the surface treatment effect on the ceramic surface was observed by scanning electron microscope (SEM). Results: This study revealed that acid etching gave superior bonding strength (8.91±2.42 A a for Obsidian and 9.05±2.87 A a for Suprinity) in comparison to sandblasting (6.94±1.1 A a for Obsidian and 6.81 ± 1.14 AB a for Suprinity), yet Laser gave the least results (4.16±0.83 B a for Obsidian and 3.94±1.1 B a for Suprinity). Conclusion: Acid etching is the best surface treatment to be used with Lithium silicate ceramics concerning bond strength, Sandblasting could be used for much less retention, while Laser at the used parameters shouldn't be used as a surface treatment for Lithium silicate ceramics.