Effects of different concentrations of bromelain and papain enzymes on shear bond strength of composite resin to deep dentin using an etch-and-rinse adhesive system.

BACKGROUND: The dentin substrate can be modified by proteolytic agents, which may affect the bonding strength of adhesive systems to the treated dentin surface. Papain, a cysteine protease enzyme with antibacterial and anti-inflammatory properties, can be used for deproteinization of dentin. An alternative deproteinizing enzyme is bromelain. OBJECTIVES: This study aimed to evaluate the impact of deproteinization on the shear bond strength (SBS) of composite resin to deep dentin using different concentrations of bromelain and papain. MATERIAL AND METHODS: Sixty upper premolars were extracted and randomly divided into 5 groups (n = 12 per group). In all groups, the dentin surface was etched with 37% phosphoric acid. Group 1 did not receive any enzyme treatment, group 2 was treated with a 10% papain solution, group 3 was treated with a 15% papain solution, group 4 was treated with a 6% bromelain solution, and group 5 was treated with a 10% bromelain solution. After applying an etch-and-rinse adhesive system, the specimens were restored with composite resin and the SBS was measured. RESULTS: Statistically significant differences were found between groups 2 and 3 (10% papain and 15% papain, p = 0.004), groups 2 and 4 (10% papain and 6% bromelain, p = 0.017), groups 4 and 5 (6% bromelain and 10% bromelain, p = 0.021), and groups 3 and 5 (15% papain and 10% bromelain, p = 0.005). CONCLUSIONS: Deproteinization with papain and bromelain at different concentrations after acid etching did not affect the SBS of composite resin to deep dentin when using an etch-and-rinse adhesive system. However, the group deproteinized with 15% papain demonstrated a higher SBS than the group deproteinized with 10% papain, and the group deproteinized with 6% bromelain showed a higher SBS compared to the group deproteinized with 10% bromelain.

Effect of Papain and Bromelain Enzymes on Shear Bond Strength of Composite to Superficial Dentin in Different Adhesive Systems.

AIM: The aim of this study was to compare different dentin treatments and adhesive systems on shear bond strength (SBS) of composite to superficial dentin. MATERIALS AND METHODS: In this in vitro experimental study, 60 extracted human upper premolars were cut 0.5 mm deep under occlusal DEJ and were randomly divided into six groups (n = 10) based on the method of dentin treatment and adhesive system: (A) two steps self-etch adhesive system (Clearfil SE bond) and (B) two steps of total etch bonding system (Adper single bond 2). (C) 10% papain + Clearfil SE bond. (D) 10% papain + Adper single bond 2. (E) 6% bromelain + Clearfil SE bond. (F) 6% bromelain + Adper single bond 2. Then, a plastic mold was placed on dentin and filled with resin composite. Shear bond strength (MPa) was tested by a universal testing machine (Zwick/Roell Z020, Germany), and the data were statistically analyzed by two-way ANOVA and Tukey's test (p < 0.05) and were applied for mean comparison. RESULTS: A significant difference was detected in the SBS evaluation between the applied adhesive systems (p = 0.0007). The SBS was also significantly affected by the interaction of treatment and etching techniques (p = 0.028). The group with 10% papain as a deproteinizing agent before the self-etching adhesive system showed the highest SBS (p = 0.029). There were no significant differences considering the specimens exposed to papain before the total etch adhesive system (p = 0.13), and the specimens were exposed to bromelain enzyme before self-etch and total etch adhesive systems (p = 0.25, p = 0.84, respectively). CONCLUSION: Papain enzyme treatment with the self-etch adhesive system increased the SBS value. Additionally, the application of bromelain enzyme as dentin treatment before two adhesive systems and papain before total etch adhesive system had no effect on the SBS of composite to superficial dentin. CLINICAL SIGNIFICANCE: Application of adhesive systems and dentin treatment can influence the bond strength.