Effect of different surface treatments on the repair strength of a nanofilled resin-based composite

Abstract

The purpose of our study was to re-evaluate the effects of surface treatment on the bond strength of repaired methacrylate-based dental composite materials including nanofillers (Ceram X, Dentsply). The microtensile bond strengths were measured before or after thermo-mechanical fatigue simulation. The treatments were as follows: (1)No treatment (negative control), (2)Bonding agent, (3) Acetone, (4)Acetone+Bonding agent, (5)Silane, (6)Silane+Bonding agent. In the digitized SEM image of the polished aged specimens without any surface treatment, the percentage of the visible fillers relative to the whole image was calculated. Before and after fatigue, no significant differences could be observed among the different pretreatment groups. Fatigue increased the microtensile strength values of Acetone and Silane groups. The digitized SEM image reveals that 11.5% of the exposed surface could be identified as uncovered filler surface. None of surface treatments (acetone, silane and bonding agent) contributed to increase the tensile strength of repaired composite samples including nanofillers.

Repair of silorane-based composites: Microtensile bond strength of silorane-based composites repaired with methacrylate-based composites

“…However, the differences between the groups with and without bonding agents were not significant, because Ceram X can be classified clinically as an easy-to-sculpt composite, and, on the other hand, this makes it easier to adapt it to the repair surface. In our previous study, it is reported that the application of Xeno V had nearly no additional benefit on the repair strength of Ceram X for the same reason 12) . Higher-filled or less sculptable composite materials such as Filtek Silorane might benefit more from the application of a bonding agent, as described in our precious study of the repair strength of Silorane 13) .…”

“…Before fatigue simulation, all treatments of this study led to bonding between the silorane-based material and the methacrylate-based repair composite that is strong enough to be clinically useful, compared with the repair bond strength between the same composites under the same conditions in our previous studies for reference 12,13) . Thermocycling is a combination of hydrolytic degradation and thermal stresses and is a method to simulate temperature-related breakdown by repeated sudden temperature changes.…”

“…The most common suggestions include increased surface roughness 7,8) , silane treatment 9,10) and the application of a low viscous bonding agent 10,11) . In our previous study, we evaluated the effects of surface treatments on the bond strengths of repaired methacrylate-based dental composite materials including nanofillers 12) and repaired silorane-based dental composite materials 13) . The purpose of the present study was to evaluate how to optimize the bond strength of silorane-based dental composites when they are repaired with a methacrylate-based restorative material.…”

Two-Year Interfacial Bond Durability and Nanoleakage of Repaired Silorane-Based Resin Composite

“…15,23 The silane also enhances the wetting of the surface for the bonding agent, which is expected to infiltrate more easily through the irregularities created by the surface roughening. Previous researchers, 22,[24][25][26][27] who used silane primer in repairing methacrylate-based resin composite, proved that it had no significant effect in the repair bond strength. On the contrary, some researchers 5,10 confirmed the important role of silane primer when silorane-based resin composite was repaired with methacrylate-based adhesive/ repair composite but not with the silorane-based intermediate adhesive agent/repair composite.…”

Adhesion of substrate–adherent combinations for early composite repairs: Effect of intermediate adhesive resin application

“…Adhesion between two composite resin layers is achieved in the presence of an oxygen-inhibited layer of unpolymerized resin [7,16]. However, controversial opinions exist on the function of oxygeninhibited layer on the adhesion between two composite resin layers [17][18][19].…”