The potential effect of proanthocyanidins on the stability of resin-dentin bonds against thermal cycling / 中华口腔医学杂志

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the potential effect of proanthocyanidins (PA), a natural cross-linker, on the stability of resin-dentin bonds against thermal cycling.</p><p><b>METHODS</b>Ten percent, 15% PA-based preconditioners, and 5% glutaraldehyde were prepared for the transient pretreatment of demineralized dentin before bonding. Specimens without pretreatment were used as negative controls (n = 4 teeth for each group). Microtensile bond strength, failure mode, micromorphologies of resin-dentin interface and the collagen degradation of bonded specimens after thermal cycling were evaluated.</p><p><b>RESULTS</b>After thermal cycling, the microtensile bond strength values of resin-dentin bond in groups pretreated with 15% PA for 120 s and 60 s [(23.09 ± 3.19) and (21.88 ± 3.49) MPa] were significantly higher than that in control group [(15.47 ± 3.78) MPa] (P < 0.05). Mixed fractures were the most prevalent failure mode. Specimens with pretreatment presented compact hybrid layer, while some narrow gaps were found in hybrid layer of non-treated specimens. Collagen biodegradation rates in groups with pretreatment were significantly lower than that in control group (P < 0.05). Among them, specimens pretreated by 15% PA preconditioner for 120 s exhibited the lowest biodegradation rates [(0.316 ± 0.019) mg/g].</p><p><b>CONCLUSIONS</b>The application of natural cross-linker PA on demineralized dentin reduced the bond degradation against aging by thermal cycling, and can be helpful to create more durable bonds to dentin.</p>