Bond strength to dentin after chemomechanical caries removal

This study aimed to evaluate bond strength of self-etching adhesive to dentin following chemomechanical dentin or burs carious removal.

Twenty-two sound molars were sectioned transversely to achieve complete exposure of dentin, followed by the induction of artificial caries. The teeth were randomly divided into two groups: Brix-carious dentin removal with papain-based gel (Brix 3000), and Burs-carious dentin removal with drills. A morphological analysis of prepared dentin was performed on two samples from each experimental group using scanning electron microscopy. Teeth were restored using a self-etch adhesive system (Clearfil SE Bond, Kuraray) and composite resin (Filtek Z350 XT, 3M Oral Care). For the microtensile bond strength μTBS test, beams were tested under tensile stress after 24 hours of storage in distilled water. Fractographic failure mode was performed using a stereomicroscope and two beams from each group were analyzed using scanning electron microscopy (SEM). The data were analyzed using an independent samples t-test with a significance level of α=0.05.

The μTBS ranged from 23.84 ± 5.77 MPa for the Brix group to 28.91 ± 4.82 MPa for the burs group. There was no statistical difference between the groups (p = 0.06). The adhesive failure was the most prevalent in both groups.

The chemomechanical carious dentin removal using papain gel formulation Brix3000® did not affect bond strength compared to bur removal method. Key words:Dental caries, Tensile strength, Dental adhesive.