Silane-Containing Universal Adhesives Influence Resin-Ceramic Microtensile Bond Strength

Background: Silane-containing universal adhesives (UAs) are marketed as adhesion promotors for glass-ceramics. Objectives: This study aimed to evaluate the priming capacity of gamma-methacryloxypropyltrimethoxysilane (gamma MPTS)-containing and gamma-methacryloxypropyltriethoxysilane (gamma MPTES)/3-(aminopropyl)triethoxysilane (APTES)-containing universal adhesives (UAs) for lithium disilicate ceramic (LDC). Materials and Methods: Etched LDC discs were distributed into four groups according to the priming material used: (control), no priming; (MBN), LDC was primed with a universal primer (Monobond N); (SBU), gamma MPTS-containing UA (Single Bond Universal Adhesive) was used as a primer; and (SBP), gamma MPTES/APTES-containing UA (Scotchbond Universal Plus Adhesive) was used as a primer. LDC discs were cemented using a dual-cure resin cement, then sectioned into microbeams for microtensile bond strength (mu TBS) evaluation. Failure modes were assessed. Results: MBN application showed the highest mu TBS among all groups. gamma MPTES/APTES-containing UA (SBP) resulted in considerably higher mu TBS compared with gamma MPTS-containing UA (SBU) or the control group. The mixed failures were the most predominant among all groups. Conclusions: The effect of silane-containing UAs on resin-ceramic mu TBS is material dependent. Although gamma MPTES/APTES-containing UA improved bonding to LDC, the priming of LDC with either of the UAs tested cannot be considered as an alternative to a separate silanization (priming) step using a universal primer.