Materials and Methods: Thirty extracted mandibular molar teeth were decoronated at the level of cementoenamel junction horizontally to expose pulp chamber floor. The individual tooth was then embedded in self-cure acrylic resin. The specimens were randomly divided into three groups (n = 10). Group A: control group, was treated with 3% sodium hypochlorite (NaOCl) for 30 min followed by a final rinse with 17% ethylenediaminetetraacetic acid (EDTA) solution for 3 min; Group B: after pretreatment with 3% NaOCl and 17% EDTA, it was further treated with 10% sodium ascorbate for 10 min; and Group C: after pretreatment with 3% NaOCl and 10% EDTA, it was further treated with 10% pine bark extract for 10 min. After drying the specimens, a bonding agent was applied to the pulp floor dentin followed by a composite restoration. Specimens were tested under a universal testing machine to determine the shear bond strength. The data obtained were tabulated and statistically analyzed using analysis of variance (ANOVA) and Bonferroni post hoc test.

Results: The 10% pine bark extract group showed highest mean shear bond strength, followed by 10% sodium ascorbate group.

Conclusion: Among the antioxidants used, 10% pine bark extract application showed highest shear bond strength.