Effect of Different Silane Treatments on Long-Term Bonding Between Non-Etched Glass-Ceramic and Resin Cement

Abstract

The present study evaluated the bond strength between glass-ceramic and resin cement, using different silane treatments, performing no previous hydrofluoric acid (HF) etching on ceramic surface, after short- and long- term storage. One hundred and eighty glass-ceramic plaques (IPS e.max CAD®) were polished and divided into six groups (n=30) to receive different silane treatments: (1) RCP-RelyX Ceramic Primer® (one-bottle silane), (2) RCP+SB-RelyX Ceramic Primer and Adper Singlebond2® (silane plus separated adhesive), (3) SBU-Scotchbond Universal® (silane-containing universal adhesive), (4) CP-Clearfil Ceramic Primer® (silane/MDP primer), (5) NC-no-silane (negative control) and (6) PC-Previous HF etching (5%, 20s) plus RelyX Ceramic Primer® (positive control). Two resin cement cylinders (Rely X Ultimate®) were built on each plaque. Each group was divided into two sub-groups to be stored for 24 hours (24h) or 6 months (6mo) in distilled water at 37°C (n=15). Then microshear (µSBS) testing was performed. Failure mode was analyzed using scanning electron microscopy (SEM). Data were statistically analyzed by two-way ANOVA and Tukey´s test (α=0.05). Both factors and their interaction resulted statistically significant (p≤0.05). PC obtained the highest µSBS values (in MPa) at both storage times (24h: 28.11±2.44; 6mo: 19.10±3.85). After 24h storage, groups RCP+SB (10.86±3.62), SBU (8.37±4.33) and CP (8.05±3.62) were not statistically different from NC (8.00±2.51); only RCP (19.73±4.63) and PC obtained higher values. After 6 months, only PC showed higher values than NC (0.04±0.01). Cohesive failure in resin cement was more prevalent for RCP-24h and PC, while adhesive failure was more frequent among all other groups. Clinical relevance: None of the commercially available silane primers tested, improve long- term ceramic/cement bonding without performing HF etching on ceramic surface. Combination of HF acid and silane, remain as a gold standard treatment for glass-ceramic materials.

Effect of Surface Pre-treatments and Thermocycling on Microtensile Bond Strength of Lithium Disilicate Glass Ceramics to Self Adhesive Resin Cement

“…In agreement with these findings, El-Damanhoury and Giantantzopoulou 10 revealed that, the use of 5% hydrofluoric acid etching followed by Monobond Plus improved the microtensile bond strength in comparison to conditioning with Monobond Etch and Prime. In another study by Murillo et al, 25 Combination of 5% HF acid and silanization proved to be the gold standard treatment for Lithia-based glass-ceramic materials.…”

Effect of different silane coupling agents on the wettability and shear bond strength between glass ceramic and resin cement

“…(74) The co-existance of the different types of hydrophobic/hydrophilic monomers may act as a barrier, preventing the silane monomer from establishing intimate contact with the ceramic surface. (75) Kerr silane primer (KP), silane containing resin-monomer, offered the least strength compared to other groups of silane coupling agent. The bond strength achieved when Kerr silane primer was applied was not significantly differ than that of the negative control group (NS) even though the wettability of the resin was improved.…”

“…(61) Although treating the lithium disilicate surfaces with silane coupling agent may seem to reduce the wettability of the substrate surface to deionized water, hydrofluoric acid etching along with silane application are proven to be the gold standard treatment protocols that are crucial to obtain optimal bond. (27,76)…”