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

Abstract

Background: Silane-containing universal adhesives (UAs) are marketed as adhesion promotors for glass-ceramics. Objectives: This study aimed to evaluate the priming capacity of γ-methacryloxypropyltrimethoxysilane (γMPTS)-containing and γ-methacryloxypropyltriethoxysilane (γMPTES)/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), γMPTS-containing UA (Single Bond Universal Adhesive) was used as a primer; and (SBP), γMPTES/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 (μTBS) evaluation. Failure modes were assessed. Results: MBN application showed the highest μTBS among all groups. γMPTES/APTES-containing UA (SBP) resulted in considerably higher μTBS compared with γMPTS-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 μTBS is material dependent. Although γMPTES/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.

“No-Primer” Resin Cementation of Lithium Disilicate Ceramic: A Microtensile Bond Strength Evaluation

“…Although those guidelines were set primarily for the evaluation of resin-dentin and resin-enamel μTBS, they could be also applied for evaluating the bond (adhesion) strength of dental ceramics. Additionally, an intra-oral cementation procedure was simulated by cementing the ceramic discs under force rather than applying the resin cement onto the ceramic surface passively [ 13 , 17 ]. This was thought to ensure intimate contact between the resin cement paste and the ceramic surface and to minimize chances for void formation within the resin cement.…”

“…This can be explained by the priming efficacy of the universal (silane-containing) primer applied prior to the resin cementation. As far as such a primer was applied correctly and air-dried sufficiently, the formation a consistent silane film on the primed ceramic surface could promote chemical bonding between the ceramic surface and methacrylate-based resin cement [ 12 , 13 , 21 , 22 ]. Apparently, resin-ceramic bonding can be attributed to silane priming either before (γ-MPTS primer) or simultaneously during the application of LCSI-containing resin cement.…”

“…To specify, each microbeam consisted of two ceramic parts cemented together. This might have reduced the incidence of cohesive failures in the substrate (ceramic) due to its high mechanical properties [ 13 ]. The fractographic assessment of the tested microbeams indicated that, except for the PSAP group after aging, which presented the highest incidence of adhesive failures, all the microbeams of the other groups showed mixed failures.…”

“…To simplify the priming step of glass-ceramic materials, silane-containing adhesives have been introduced. However, such adhesives failed to be reliable alternatives to the commercially available silane-containing primers [ 11 , 12 , 13 ]. Recently, a novel resin cement containing trimethoxysilyl long-chain alkyl methacrylate monomer (long-carbon-chain silane (LCSI)) was introduced to simplify the cementation procedures of LDC restorations.…”