Polymerization shrinkage/stress and dentin bond strength of silorane and dimethacrylate-based dental composites

This study was designed to determine whether a new dedicated adhesive system using a silorane composite exhibits better bonding performance to human dentin than conventional dimethacrylate-based composites. The materials were used included: Adper(TM) Easy Bond-Z250 (AE-Z250), iBond-Venus (IB-VE), XenoIII-TPH (XE-TPH), Clearfil S3-Clearfil Majesty (S3-CM), and the Filtek silorane system (SA-FS). Polymerization volumetric shrinkage and stress development were measured using a micro-CT instrument and universal testing machine. The push out strength of the bonds produced using the corresponding self-etching adhesive systems were also measured. The volumetric shrinkage of the resin composite/adhesive combinations ranged from 1.05% (SA-FS) to 3.38% (XE-TPH) 30 min after light curing. SA-FS had the lowest volumetric shrinkage (P < 0.05), followed by S3-CM, EA-Z250, IB-VE, and XE-TPH. The polymerization stress of the materials ranged from 1.54 (SA-FS) to 3.49 MPa (S3-CM). The lowest stress was also observed in SA-FS at 30 min during the stress test (P < 0.05). Push-out bond strength testing revealed that IB-VE had significantly lower bond strength than other combinations (P < 0.05). The silorane composite and dedicated adhesive system exhibited excellent characteristics of low volumetric shrinkage and stress development compared to conventional dimethacrylate-based composites. However, the silorane composite resin system possessed similar push-out bond strength as the other materials, with the exception of the Venus/iBond combination. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012