Dentin bonding of light- and self-curing resin composites using simplified total- and self-etch adhesives

Objectives: The purpose of this study was to evaluate the influence of (1) the curing mode of resin composites and (2) activators for dual curing of the bonding on dentin bond strength. Methods: The light-curing resin composite Brilliant (B) and the self-curing resin composite Brilliant MH were bonded with the following adhesives (n = 10): OptiBond FL, Excite, Prime&Bond NT, OptiBond Solo Plus, Adper Prompt L-Pop, Clearfil SE Bond, Xeno III, and AdheSE. Excite, Prime&Bond NT, and OptiBond Solo Plus were also used in combination with activators for dual curing. Tensile bond strengths were measured after 24 hours of water storage (37°C), and fractured surfaces were analyzed in the scanning electron microscope. Results: Except for Excite/dual curing and Prime&Bond NT/dual curing, bond strengths with Brilliant MH were significantly lower than with Brilliant. Activators significantly increased bond strengths in Excite/Brilliant MH, but not in Prime&Bond NT/Brilliant MH and OptiBond Solo/Brilliant MH. Conclusions: This study confirms the incompatibility between self-curing resin composites and simplified bonding systems containing acidic components. Activators for dual-curing the bonding eliminated this chemical incompatibility only in 2 of 3 bonding systems. The use of these activators in combination with light-curing resin composites must be avoided. Keywords: dentin bonding, composite, bond strengths