Pomegranate extract on eroded dentin: antioxidant action, bond strength and morphology of the adhesive interface after aging

Abstract

Objectives This study aimed to evaluate the effect of pomegranate solution ( Punica granatum ) on eroded dentin through antioxidant action, shear bond strength (SBS) and interface morphology. Materials and Methods The 10% pomegranate peel extract was prepared by the lyophilization method. Punicalagin polyphenol was confirmed by high-performance liquid chromatography. Antioxidant activity was evaluated by capturing the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical. For the SBS, 48 dentin fragments were divided into sound or eroded, and subdivided according to the pretreatment ( n = 12): water or P. granatum . The surfaces were restored with self-etch adhesive and a bulk-fill resin (Ecosite; DMG). The SBS was done immediately (24 hours) and after thermal cycling + water storage (12 months). For scanning electron microscopy, 48 dentin fragments (24 sound and 24 eroded) received the same treatments as for SBS ( n = 6), and they were analyzed after 24 hours and 12 months. Results The P. granatum had antioxidant action similar ( p = 0.246) to the phenolic standard antioxidants. After 24 hours, eroded dentin had lower SBS than sound dentin ( p < 0.001), regardless of the pretreatment. After 12 months, P. granatum maintained the SBS of sound dentin (13.46 ± 3.42 MPa) and eroded dentin (10.96 ± 1.90 MPa) statistically similar. The lowest values were found on eroded dentin treated with water (5.75 ± 1.65 MPa) ( p < 0.001). P. granatum on eroded dentin caused peritubular demineralization and hybrid layer with resin tags. Conclusions The pomegranate extract had antioxidant action and preserved the adhesive interface of the eroded dentin.