Interfacial fracture toughness of self-adhesive and conventional flowable composites to dentin using different dentin pretreatments.

AIM

The aim of the present study was to investigate the effect of different dentin pretreatments on the interfacial fracture toughness of a self-adhesive flowable composite to dentin compared with that of a conventional flowable composite.

METHODS

Caries-free human molars were sectioned to expose the underlying dentin and were randomly divided into seven groups (N = 12) of dentin pretreatments bonded to a self-adhesive flowable composite (Vetise Flow, VF) or a conventional flowable composite (Clearfil Magesty Flow, CM). For VF; Control group (group C-VF), there was no pretreatment, self-etching primer (SP), oxalate dentin desensitizer (OX), and chlorhexidine gluconate (CH) were used. For CM; SP (group SP-CM), OX followed by SP (OX-CM), and CH followed by SP (CH-CM) were used. The interfacial fracture toughness was measured using a universal testing machine. Data were analyzed by Kruskal-Wallis test and analysis of variance.

RESULTS

For VF, the fracture toughness of SP-VF was significantly higher than that of other groups. For CM, a significantly higher fracture toughness for SP-CM than that of OX-CM was found. For all dentin pretreatments, the fracture toughness values were significantly higher for CM compared with the VF.

CONCLUSIONS

The self-adhesive flowable composite had reduced bonding efficacy to dentin compared with that of the conventional flowable composite, regardless of the type of dentin pretreatment.