Self-adhesive flowable giomer (SAG) has been used in dental practice recently to simplify clinical procedures and shorten chair times. However, there are only few studies evaluating its bond strength to enamel and dentin, resulting in a lack of eviden...
Self-adhesive flowable giomer (SAG) has been used in dental practice recently to simplify clinical procedures and shorten chair times. However, there are only few studies evaluating its bond strength to enamel and dentin, resulting in a lack of evidence. This in vitro study aimed to evaluate the micro-shear bond strength (μ-SBS) of SAG bonded with or without a dental bonding system to enamel and dentin, both before and after thermocycling.
Sound bovine teeth were used as the tooth substrates. For μ-SBS tests, enamel and dentin specimens were prepared for SAG (Beautifil Kids SA - BK), a self-adhesive flowable composite (Vertise Flow - VF), and a nanohybrid flowable giomer (Beautifil Flow Plus F03 - BF). Two adhesive modes were tested for BK and VF (with self-etching adhesive and no adhesive), and one for BF (with self-etching adhesive). The μ-SBS test was conducted after 24 h and after thermocycling for 10,000 cycles using a universal testing machine.
For all materials, when self-etching adhesive was used, the μ-SBS was significantly higher than that of no adhesive group (p < 0.05). No statistically significant difference was found between the restorative materials under any condition. Thermocycling had no significant effect on the μ-SBS of BK. In self-etching adhesive group, mixed failure was predominant for all materials. However, in no adhesive group, adhesive failure and mixed failure were observed at similar levels for all materials.
The bonding performance of self-adhesive material to the dental substrate was significantly weaker without adhesive compared to conventional adhesive. No statistically significant difference was found between the restorative materials under any condition. BK and BF were negligibly affected by thermocycling, but VF was affected. Therefore, this study showed that self-adhesive flowable composite has lower bond strength stability in enamel and dentin compared to SAG.