Effect of enzymatic-based chemomechanical caries removal on dentine bonding.

Abstract

Objectives: The aim of this study was to evaluate the effect of enzymatic-based chemomechanical caries removal method on bonding of self-etch adhesives to caries-affected dentine. Methods: Seventy-eight permanent molars exhibiting frank cavitation on the occlusal surface reaching dentine were used in the study. Forty-eight teeth were randomly divided into three groups (n=16) according to the caries excavation method: Group 1: Papacarie (Formula & Acao, Brazil), Group 2: Carisolv (MediTeam, Göteborg, Sweden), Group 3: round carbide bur. After caries removal, each group was further subdivided into two groups (n=8) for bonding with two-step self-etch (Clearfil SE Bond, Kuraray) or one-step self-etch (Clearfil S3 Bond, Kuraray) adhesive, following manufacturers’ instructions. Composite build-ups were performed using Filtek Z250 (3M ESPE). After 24h storage in distilled water, the bonded teeth were sectioned into 0.8mm2 beams and stressed to failure for microtensile bond strength testing. Bond strength data was analyzed using 3-way ANOVA (caries excavation method, adhesive type and dentine type) and Tukey’s post hoc multiple comparison test (α = 0.05). The remaining 30 carious molars were similarly randomly distributed into 6 groups (n=5) for interfacial nanoleakage evaluation using field-emission scanning electron microscopy.

Results: The results of three-way ANOVA revealed that bond strength was not significantly affected by the “caries excavation method” (p>0.05), but affected by “adhesive type” and “dentine type” (p<0.001). The microtensile bond strength of two-step self-etch adhesive was significantly higher than one-step self-etch adhesive (p<0.001). For two-step self-etch adhesive, the bond strength to sound dentine was significantly higher than residual caries-excavated dentine. Higher silver penetration was found in the bonded interfaces of residual caries-affected dentine and one-step self-etch adhesive groups.

Conclusions: The enzymatic-based chemomechanical caries removal method did not interfere with bonding to caries-affected dentine. It can be used as an alternative to sodium hypochlorite-based chemomechanical caries removal method.