Bond strength of a dental leucite-based glass ceramic to a resin cement using different silane coupling agents

To evaluate the effect of different types of novel silane coupling agents with two concentrations on the micro-tensile bond strength of a dental glass ceramic with leucite crystals to a dual-cured resin cement using an optimized method of silane application.

Leucite-reinforced feldspathic ceramic blocks were fabricated, wet ground and cleansed. The bonding ceramic surfaces were treated with different organosilane solutions as follows: Control silane: Monobond S; methacryloxypropyltrimethoxy silane and experimental silanes with two concentrations (1.0 and 2.5 vol%): amino, isocyanate, styryl, and acrylate silanes. The silane application method consisted of brush application, hot air drying followed by rinsing with hot water and drying. Then a thin layer of an unfilled resin and a dual-cured resin cement was light-cured on the ceramic surfaces. The resin-ceramic blocks were stored in distilled water at 37°C for 24 h and sectioned to produce beam specimens (n=17) with a 1.0 mm(2) cross-sectional area. Specimens were then subjected to thermocycling and tested in a micro-tensile tester device. Data were analyzed using analysis of variance and Tamhane post-hoc test.

The mean micro-tensile bond strength value for the styryl silane was significantly higher (P<0.05) than the other types of silanes except for the Monobond S. The mean bond strength values for isocyanate silanes were significantly lower than the other silanes tested (P<0.05). No statistically significant difference in the bond strength between the 1.0 and 2.5 vol% of experimental silanes was observed (P>0.05).

The micro-tensile bond strength of the leucite-based dental glass ceramic to a resin cement was affected by the type of silane coupling agent and not by the concentration of silane solutions. The best bond strength overall was achieved by methacryloxypropyltrimethoxysilane and experimental styryl silane solutions.